I call her Big Blue #119 - Columbus, Ohio

[IMMark]

Can someone tell me, what actually hits the x rail stopper block (10 10 248)?
Is there something on the gantry that hangs down and catches it?
Also, regarding installing the x rails; did any of you make the holes through the main x beam somewhat larger to give some adjustment room for the x rails? Or is that not a good idea?
Thanks
Mark

[parrulho]

is the limit switch support bracket... M1 18 000. About the holes on main beam they are already more large on rails to give adjustment.

[IMMark]

Thanks Paulo
I appreciate the answers!
Of course, it brings up more questions. Does anyone know (maybe Metalhead)...why are the stop blocks (SB4) sold as a set of 3? Am I missing something here....don't you need 4 of them?
Mark

[Alan_c]

2 for the gantry (1 on each side) and 1 on the Y-car, the gantry needs 2 because its so wide and is possible to twist out of shape, the Y-car is very stiff and relatively small so only needs the one (it fits on the side where the motor is mounted)

[IMMark]

Thanks Alan...that makes sense.
Mark

[IMMark]

I have another couple of questions.
1. As far as the installation of the racks. Is the general consensus, to use tape only or to still attach each end with bolt?
2. Regarding Prox. Sw. target hole, is it drilled all the way through the rail, but stops at the main x beam?
3.Can Prox. Sw. be added later, if the target hole is drilled and the mounting hole through the stopper/limit Sw. assembly? Is wiring them in later anything consideration?
4. How long is the adjusting bolt through the x rails stop blocks? I am in the US and went with 5/16-24 holes in the blocks.
As always, thanks for any input!
Mark

[smreish]

1. VHB tape is fine only
2. Hole thru the rail, but not into the main beam
3. yes, any of the proximity sensors can be added later. The stops should be installed during initial build and are important.
4. my machine used a 2" fully threaded bolt w/ jam nut. Threaded the square bar stock and welded it to the rail as noted in drawing past the proximity hole. This gives you about 1/2" of fine adjustment of gantry square. More than enough.

[IMMark]

Fast reply..and all answered : )
Thanks!
Making progress, I am sure there will be more questions...but it is coming along!!!
Mark

[IMMark]

Two more questions.
Is it critical if the X rails are 1/8" short?
Regarding painting the X rail. Do you try to tape off the gtound part orpaint it all and sand the paint off the ground part?
Thanks
Mark

[smreish]

What is mostly affected is the swing of the motor plate and the size of the pinion.
For the most part, you should not be affected.

If you have a 30-35T pinion...no issue. If you have a small 20 or 24T pinion you may not fully swing into full engagement in the rack. I have been there! :)
Regardless. You should be okay.

Tape off the V area. Or, it will wear off in about a week! Not terribly critical.

[IMMark]

Great news...and thanks for the fast replies!
More to come I am sure.
Mark

[smreish]

...glad to help when we can.

[IMMark]

Couple of more questions...
Regarding stopper lip (M1 18 022)
The specs call for a thickness of .200", I would like to be able to use .250".
Is it ok to use the thicker stock, and if so...do I need to adjust the overall height of the finished assembly, to accommodate the extra .050"?
Also, I am a self taught metal worker (and still teaching myself stuff)...so, how do you guys make the wedge shaped cuts in the angle iron of the same part?
Thanks for any advice!
Mark

[pblackburn]

I used 0.250 angle.

[pblackburn]

You need that cutout for the prox switch if you are using one. I used a mill but it can be done with a bandsaw and grinder, a grinder with cutoff wheel, only your imagination is your limit there.

[IMMark]

Thanks Pete
After looking at the drawings again..I guess the thicker stock doesn't effect it. I was thinking it would make the height .050" too much...but it is still just 1" wide.
I have a milling machine too...still learning how to use it...but I was going to give it a try, using a swivel vice? 2nd option was to go at it with a cut off wheel.
I will see how it goes...thanks again for the suggestions!
Mark

[IMMark]

Time for some more questions!
Regarding the spacing of the v wheels for the z plate. The post here; http://www.mechmate.com/forums/attachment.php?attachmentid=1721&d=1215270307
States to add 11mm for the hole spacing in the spider. The v wheels that I have are from Superior Bearing (where I think most people get theirs from) but the bore on them is listed as 0.4724" (0.039") difference from the 11mm? Am I missing something here...any input is appreciated.
Thanks
Mark

[smreish]

The v wheel spacing in the drawings is only a GUIDE to layout.
Depending on your z-plate stock (which in many places in the work is either 100mm or 4" (which is 101.6mm).
The bearings which are BWC compliant should be 12mm and the offset studs are 1/4" bore with 12mm shank. The Superior bearings should be 12mm which is .4724" imperial.

[IMMark]

Thanks Sean
I made a mistake and had to re-weld the holes. I am triple checking everything this time!
Thanks for putting my mind at ease.
Mark

[IMMark]

Does this sound like it meets the E chain requirements?
ID: 15/16" x 1 1/2", OD: 1 3/16" x 2" , Bend radius 5.5" chain center to chain center?
Thanks
Mark

[smreish]

looks small to me.
I used IGUS E-chain that was almost 3" wide, 1.75" tall and bend radius of 8" (or 6")...but much larger than what you have.

The inside fills up quickly.
3 - 4 core18 gauge
1 - air hose
1 - 12/3 for router or spindle
1 - 7 core control cable
2 - 18/2 for button station extras
...air

[IMMark]

OK, thanks.
I wonder if it would be ok for the Y run?
Also, what do you use the air line for?
Mark

[smreish]

Air line I have used for many things, but mostly:
- air powered automizer for cooling of tool when cutting alum or plastic
- blow air to direct the dust pickup with 1/2 of dust shoe removed when using specialty cutters
- run air drill when I change out spindle for drilling operations.
- I also test using it with my DA sanders as a type of polishing fixture ( once )

[IMMark]

Thanks for the tips...must have airline :D
Looks like Igus E26.07.063 should handle all needs?
As for placement of the fixed end, is it located at table center or is there an offset?
Also, as a side note...on laser cut parts, do you knock the "sharp" edge off ?
Thanks
Mark

[smreish]

Fixed end placement? Can you elaborate? - not sure what your asking.
I touched all the laser parts with flap wheel disk to break all the edges (the paint sticks better on smooth edge)


The igus you picked will do...I found that or similar on Ebay when I built my machine.

[Fox]

I used a BD powerfile for breaking the edges of the lasercut parts. It gives you more control and you can enter smaller corners than you can with the flapper disc. One of my favorite tools, I use it very often on all kinds of materials and projects. But a flapper disc and some hand files will do as well. Even hand files alone will do. The paint will creep away from the sharp edges if you don't do this.

[IMMark]

Sorry, by fixed end. I meant the largest of the cable chain shelf parts. I don't see where it placement is on the main x beam?
Also thanks for breaking edges tips Fox and Sean....I have started doing them now.
Mark

[IMMark]

Also, Sean I read your post in the E Chain section, regarding the length of chain to order for a 5 x10 table...buying in 5 feet sections , 3 would be more than enough (15 feet total) for both the x and y's?
Dose that sound right?
Thanks
Mark

[smreish]

Mark,
15' should be enough.

The quick calculation for the correct amount of chain is 1/2 (length of axis travel) + 1/2 bend diameter + a little bit.

So, in practice, if you have a 10' table, you will need 5' move + 2.33' bend + a little extra for the x axis. Which is about 9'

The y axis is 2.5' move + 2.33' bend + a little. Should be about 5.7'

Just double check the bend radius for that IGUS chain to be certain that you have enough length to make the 1/2 diameter distance without being short.

[IMMark]

Thanks!
I wanted to be sure about the formula. Igus lists the radius as 2.48-9.84. I guess that is a min. and max?
Why thoughts on my placement question? I may not have explained it well. I am not sure how to determine where along the main x beam, to attach the first bracket that will support the fixed end of the E chain. Is it at the center of table length it is there an offset?
Thanks
Mark

[smreish]

Mark,
The actually location is really where ever you want to.
To find the shortest usable length, I attached a 2x4 with clamps at the bottom of the c channel and then attached the e-chain to the car. Manually moved back and forth until I found the static link that didn't bend or move. It was about mid point, but slightly beyond to keep the last few links flat on the support bar.

This let me set the correct attachement height of the support bar and length to match the best bend radius of the chain. The bigger the radius, the better for the cables and air line inside e-chain.

Does that make sense?

[IMMark]

That makes perfect sense!
Thanks so much fir your help. I have ordered the E chain and will wait till I have it in hand.
I am getting close on this thing!!!
Do you think there would be any issues, with putting the stop blocks for the Y rail....in the rail without the rack? Three plans call for them to be on the rail with the each.
Thanks
Mark

[smreish]

x rail - 4 stops (2 each side on each end)
y rail - 2 stops only (1 each end)
No problem putting them on now. Make sure to notice that the Y CAR end stops are SHORTER than the ones for the x rail. Welding the wrong ones on will block the car travel. ( I Know how this is a bad thing) :)

[IMMark]

Yes, I have the 4 X stops welded on. I have the Y stops made (the right height :) ). But 1 of my Y rails may need to be remade...so I was hoping to weld them on the other Y rail ( the one without the rack).
I don't see where it would be a problem..but wanted to make sure.
Mark

[smreish]

The challenge with using the other side, that is not the driven side by the pinion and will exert excessive yaw on the y-car and cause it to twist when it hits the hard stop.

Put it on the correct side if you can.

[IMMark]

Got it...Probably smart to file the plans :)
One more question (at least), on the soil board...can it have a joint in it. I will have 3/4" 5 x 10 support board. But I would like to use 1/2" spoil...and can't get it in 5 x 10 size?
Also on the "extra" space to the sides of the support board, it be filed in with wood to"catch" sawdust?
Mark

[smreish]

Mark,
Joints are fine.
I used spare pieces of 1/2" MDF on my 3/4" spoil board all the time. A 2'x2 or a 4'x8' then fill in the gaps.
As long as your surfacing the table, and glue the sections down, your fine.

After a bit, you will need to replace that 1/2 part anyway.

You can fill in the side area's, but the reason they exist is so you can use G, C or bar clamps to hold your material to the spoil board.
Unless you are putting in a vac table, or using some other hold down mechanism - leave it open as designed.

[IMMark]

No vac table yet..perhaps in the future.
I will probably make some removable side boards to fill the gaps. I will be storing things under the table...so I want to keep sawdust out.
Any thoughts on tool holders. I will start out with a Porter Cable router and move to a spindle eventually. My thought is to mount it so the bottom of the collet is just above the bottom of the z plate. That way, when a bit is installed I would have max. amount of travel?
If that makes sense :)

[KenC]

Go straight to a spindle if you have the spare cash.
U really don't have to worry about the tool holder position. There are no fix rule in it. Anything that make you happy will do.

[IMMark]

I would love to start out with spindle...I checked my "spare" cash drawer...2 bottle caps and some dryer lint :D
I will have to start out with the router, I just really want to get this thing cutting! I am afraid that I may be the first 4 digit MM number :eek:
Mark

[IMMark]

Trying to get the E chains laid out....is it normal for them to extend out past the end of the main x beam (and the end of the gantry) with they machine is at its furthest position?
I mean that the loop of the E chain is what is past the table end.
Mark

[Tom Ayres]

Mine does, whether that is normal or not???? I'm pretty sure it is...

[smreish]

Yes, That is normal.
You will probably have about 8-10" past depending on your service loop.

[IMMark]

Thanks Tom and Sean....I couldn't really tell from any pictures that I found.
Moving forward!
Mark

[IMMark]

I have E chains placed, all looks good. Anything to consider regarding the wire shelf portion that leads the wire going into the chains? I have seen some people use two"pipes" on the Y axis. On the X is it a good idea to have it enclosed, to offer protection?
Thanks
Mark

[smreish]

Enclosed just helps with the dust and cleaning of machine.

[IMMark]

Thanks Sean, It must seem like a lot of silly questions....but I appreciate your input!
Mark

[Fox]

Open support also helps with dust as it can fall trough ( unless you make sure have a sealed dust proof enclosure like a control box, small dust will still travel in all kinds of places). It all depends on how you look at it. I look for efficiency when posed with these questions, which is the quickest to clean option ? I blow my machines with compressed air anyway every now and then, and then all dust will fall trough, with an enclosed box you will have to open it, and if it becomes more difficult to get the dust out, you will just blow it in deeper.

[IMMark]

Thanks Fox!
That is what I like about discussing things with others that have built or even just planning the build. Always good to get ideas and input from others in my book!
I am sure I will be coming up with some more questions (stupid and otherwise) and I tackle the "electric" side of the build!
Mark

[IMMark]

If anyone would be so kind as to have a look and make sure that I am on the right track, it would be greatly appreciated!

The setup that I have;
Motor; Kelinginc.com KL34H280-45-8A, Specs.(I plan to wire in Unipolar) 4.5 A, 0.71 ohms, 2.2mH, 8 wire NEMA 34
Drives; Gecko 203V
BoB, PMDX-126
Spur Gear, 25T (Direct drive, however I will be implementing 3:1 or 4:1 belt reduction ASAP).

As I understand the power supply choices; (I am planning to build my own PS)

24*√2.2=36 (Conservative Route)
32*√2.2=48 (Gecko Recommendation)
38*√2.2=56 (Gerald’s Recommendation)

The resulting figures (36,48,56) are VDC. As I look at the toroid transformer (looking at the Antek products), the listing will be for VAC? So that with a 40VAC, I would expect to get 56VDC after rectification?
(40*1.4=56)
For the VA, my motors at 4.5A peak (4 motors) would give me a max amperage draw of 18 amps. Using the 2/3 rule for input amperage to the Gecko’s, I am looking at 12amps max for the input .
(12*56=672VA).

So my questions (assuming that the above understandings are correct) are;
1. Is the listing for the transformers in VAC and the multiplier of 1.4 the expected VDC output?
2. Would a 600VA be sufficient or would I need to go up to the 800VA (Antek does not offer a 700VA)
3. The schematic for the transformer has 40V twice. Do I need to wire this in parallel or series to get the full VA?
4. Any opinions on the number of teeth on the spur gear 20T, 25T or 30T? (Again, this will be direct drive for a short period of time, until the addition of the belt reduction, so my main goal would be for the long term, using it with the belt reduction).
5. Any opinions on the belt reduction, 3:1 versus 4:1

Thanks in advance!
Mark

[KenC]

1. its a good approximation. you are not wrong.
2. IMHO, 300VA is enuf power for most MM. 600VA should do the job. even though its better to have more VA in a transformer, but there is always a limit, I always try to keep them smaller than 1 horse power, I'm comfrotable with 1/2~3/4 hp .
3. parallel.
4. 20T for direct drive. pinions are amongst the cheapest parts in the built.
5. Either will do. 3:1 is easier to implement.

hope this helps.

[Tom Ayres]

I'm doing 24t direct for now, going to 30t with 3.6:1 real soon, my set-up is different 70vac 1100watts, 72 was recommended, I went just under. Steppers - Longs Motors 34HS5850 parallel

[IMMark]

Thank you Tom and Ken!
I think I may have irritated some people with my questions (sometimes I must ask the same question until I am comfortable that I am doing the correct way, but we all learn in different ways). A big part for me that wasn't "clicking" (and perhaps posting will help others) was that many postings just say "V" for volts, but not designating AC or DC. So ordering the transformer for a 56VDC system, I needed a 40VAC transformer. Perhaps that will help others that are not electrical engineers? At any rate, I have ordered my last electrical components. Hope to be one step closer to a cutting MM!
Thanks again
Mark

[IMMark]

Any thoughts on the capacitor and rectifiers?
For the capacitors, I was going to use (3) 10,000uF 100VDC wired in parallel.
For the rectifier, I was going to use Bridge Rectifier, 400V, 35A, Lug Leads
I will use 12G wire with crimp on connectors.
Thanks
Mark

[Tom Ayres]

Sounds all good.

I've been running the "roadrunner" mach sample to help me tune and tighten the machine and find that the 24t runs ok but shows up as kind of rough in the cuts which turned out to be attributed to spur clearance of the ycar, the shoulder of the spur was riding on the ycar causing it not to seat 100%. All I did was move the spur inward toward the center of the car, but it goes to show how close the tolerances can be. The 30t seems real common and apparently rolls smoother in public opinion.

[IMMark]

Thanks Tom
No info on capacitors or rectifiers :D
Glad you were able to fix your problem and it didn't cost you any more $
Mark

[Tom Ayres]

Mark you should be good on those choices.

[IMMark]

Thanks Tom...trying to get my orders in before the weekend.
Started building this 13 months ago...now I am worried about getting the order in before the weekend...go figure :rolleyes:
Thanks again
Mark

[Tom Ayres]

I know what you mean, I did the same thing...many times. I just wanted to move along quickly only to find I couldn't keep up with the orders anyway:rolleyes:

[IMMark]

Yeah, I don't know if it is normal with a MechMate build...but my UPS guy has a restraining order against me, I can no longer chase the truck down my driveway and I must remain 20' away from the driver until he unloads my items :D
Mark

[Tom Ayres]

Who signs for it? Does he set the pad down on the ground and slowly backs away?

[IMMark]

Yeah, you tackle one delivery person and you get a reputation??
But he had a box of Gecko drives!
Not sure what drives you used on your build (or what others thought), but I was shocked at the size of the 203V. For some reason, I thought they would be bigger. When I got the box, I even asked "Is there a second box"? "Maybe, they sent a partial order"?

[IMMark]

Another question on the power supply. The transformer puts out the "main" voltage for the motors, but also supplies 12v and 18v. I assume that these will be output as AC voltage?
Is that correct or does it need to be rectified to DC for use with relays, etc.?
Thanks
Mark

[Tom Ayres]

It would be ac voltage without a rectifier. My power supply has a couple of capacitors, an ic (a regulator I guess) and a small bridge rectifier.

[IMMark]

Looks like 2 1000uF 35V capacitors wired in parallel and a 2A bridge rectifier is what Antek sells as an add on module for a 24v system. Do you think that would be ok for 18v and 12v? One module for each voltage.
Mark

[Tom Ayres]

Sound about right to me.

[IMMark]

Well the PS is done and working well! That's the good news.
I have hooked up the "Kitchen Project". The output voltage of the PS is correct at 55.4VDC. The LED for the drive (Gecko 203V) is on. I also hear the motor "power on" and become rigid (Kelinginc 8 wire, wired Unipolar). The BoB (PMDX-126) tests ok (this is the board only test, apply power and the correct LED's light and go out as expected). However, when I have everything hooked up (PS, drive, motor and BoB) and use the on board test (which should start and stop the motor) I get the LED on the E Stop to light. The board ships with a jumper on the E Stop to ground (which is in place and I buzzed for continuity). All jumpers and DIP switches are factory set ( I think that puts it in Normal Mode). I am at a loss on this issue? If anyone has any input or ideas, I would appreciate it!
If you need any other information, please let me know.
Thanks
Mark

[Tom Ayres]

Print a copy of the pmdx126 manual, read thoroughly, read thoroughly again, Follow the instructions for the normal test mode and run several tests, then step by step change the set-up to at least a starting point at which you will have basic real operation. Make a serious attempt at documenting a schematic. Once on the machine tweak to your liking.

[IMMark]

Yes have manual.
Have been reading for 2 weeks.
In normal test mode.
Have tried to run on board test many times and changed to other terminals on the BoB.
But no motor movement...just a red LED for E Stop?
Just not sure what problem could be.
Mark

[Tom Ayres]

Do you have the jumper still on the estop? If you connect a Normally Closed Estop button to the board or just use the jumper wire should be fine. The estop is triggered by the open circuit. Also check to see if the status LED is flashing any code (like 3 short flashes,short pause, 3 long flashes), if there it is flashing look up the code and make corrections. If no flashes then its your Estop circuit.

[IMMark]

Yes, I still have their jumper in place. That is what's odd. I don't have any E stop switch or wiring...just their jumper? No code flashes, as I get an immediate E stop fault. Then the BoB resets with no faults, until I press test again...then same thing.?

[KenC]

Been there, IMHO, its RFI/EMI playing their trickery. Unfortunately, I neither have solution nor explanation for this occurrence.
It never fail to happen whenever LPT BOB of any kind is wired for E-stop feed, its almost always trip if de-bounce is not provided, even if it doesn't show immediately, it will eventually.
I avoid E-stop feed to the BOB if I can help it. Even though its theoretical correct thing to do; Its just too much hassle...

*ps, this applies to Mach 3, Linuxcnc is less of a problem.

[IMMark]

I am not sure I understood all of that?
I am doing this on the bench (no motors on the machine yet). So my wires are only 12" long (and are not shielded, as I read you don't need them to be for the kitchen project...perhaps that is not correct?). Should I use shielded wires? If so,use them on the phase wires from the motor? (Currently using the wires from the motor directly into drive). Or shield the step, dir, common ? How do you not use the BoB for a E circuit?
Also, planning on using Mach3...but again at this point no computer..just the on board BoB test.
Thanks
Mark

[IMMark]

Forgot to add...I don't know what you mean by de-bounce?

[KenC]

If you are not E-stop feed, then you don't have to worry about this.
Why fix when there are no proplems. :)

[Tom Ayres]

If we can't figure it out you can always call PMDX and talk to Steve. He is excellent at helping you understand what the devise should be doing and how to get there. Before you do that though let's look at what you've got set up now.

What are the DIP sw's set at now? And what pins are the stepper(s) connected to?

[IMMark]

You nailed it Tom...DIP settings. I thought I had them set, but my notes were wrong. Spent a good 12 hours over the weekend. Spent 2 mins. on the phone with PMDX/Steve today...and Ihave a working kitchen project. Big thanks to Steve at PMDX, great customer service!.
Thanks for the help here too!
Mark

[Tom Ayres]

I thought so.

[IMMark]

That almost sounds like I told you so :D
Is the first thing you to when you wake up is check the MM forum?
Just noticed the 4:30 am time. What ever the time...I appreciate it!

[Tom Ayres]

No, just had a path of resolution in mind, first was the dip switches. Early bird gets the coffee :)

[litemover]

Charge Pump on?

[IMMark]

Quick question, is it a good idea to keep the motor wires as short as possible (I mean the ones that are hard wired to the motor), since they are not shielded?
Mark

[pblackburn]

My suggestion is to use only shielded wire for the steppers and the VFD motor if applicable. The length of the wire will not add to the noise if it is present unless you are storing it in a coil.

[IMMark]

Hi Pete...yes, I am using only shielded wires through out...but the length of wire that comes attached to each motor is fairly long...I just wondered if most people cut them short (because of there lack of shielding).
Also how the heck do I change the heading of my thread...I haven't had x or y questions in quite some time :)
Mark

[pblackburn]

The flying leads you are referring to? If so, it should not be too much of a problem. If you are concerned, you can wrap them with aluminum and make sure it contacts the drain wire. I left mine at the 18" it came with.

Changing the title of your thread, PM Metalhead. I haven't cut out lady bug puzzles for a long time either so I know what you mean

[IMMark]

Thanks for the help Pete...hope you (and all who celebrate it) have a Happy Easter!
Mark

[pblackburn]

And a hoppy bunny day to as well...:)

[IMMark]

Regarding the bracket to hold the end of the tension spring on the z axis (not the motor mount end of the spring). Does that need to be longer or do you use a different spring here than you do for the other springs?
Mark

[smreish]

The plans show the z-axis and spider mostly center of the car. If you move the spider forward in car or back...this will make the spring needed either shorter or longer. I waited until I was done and measured what was left...then went to the hardware store.

[pblackburn]

This all depends on your motor mount and drive system you use. My 4:1 reduction is longer than most so I opted to use the spring at the top end. This lengthened the spring a good deal so I had to figure out what the new holding strength requirement for the new spring would be. I had to do almost exactly what Sean said and accommodate for the new layout. That is the beauty of the Mechmate. Flexibility!

[IMMark]

I forgot about the position of the z within the car being adjustable....I will be adding the belt reduction (after I get the machine running to make them), so I guess there is a chance I may have to address this twice.
As always, Thanks for the input!
Mark

[smreish]

Mark...I see you asking good questions again! I trust all is going well.
Good luck to the finish line.
Best,
Sean

[IMMark]

Thanks Sean...yes all is well (all be it very slow going). I hate to say it, but there is a possibility that I can get some movement over the weekend (I mean the machine :o).
Everything seems to take sooo long. I spent half a day getting my monitor mounted (had to make a new bracket for it). Made 3 brackets to hold the switch and junction boxes, another half a day there....as they say, the devil is in the details!
If it all goes well, I will jam a sharpie in there, and see if I can make a sign!
Mark

[pblackburn]

The end seems always to be the longest part

[KenC]

Hang in there & enjoy the moment because in no time, it will be all over, just like our childhood. :(

[IMMark]

Thanks for the words of encouragement!
I am happy to report, it moves!!!
I don't have the tool holder made yet, so basically a 5 x 10 plotter (I did attach a sharpie, just to see what it was doing)....but that is still very exciting to me!
The x and y seem like they move great, I think I may have some tweaking to do on the z. Not sure that I have that squared up enough. But all in all, a big step forward. All electronics are doing what they are suppose to, sans smoke!
I probably should have spent more time working with the software before now (so a bit of a learning curve on that, but I am reading).
What I don't quite grasp yet, is the position of the machine. I don't have limit or homing switching attached yet. What is the minimum set up required? I plan to add proximity sensors at some point ( I think I can add those later?), not sure about a home switch?
Mark

[smreish]

Minimum usage doesn't require much of anything other than the hard stops to keep it from falling off the rails.

Once you define the 0,0. Park the gantry and y car (or jog it) to the 0,0 you want. Then in Mach set it all 0,0,0. Define the table size in the limits in Mach. This will be a configuration page that you set the coordinate data size of your table. Like 0,48 and 0, 96 if you have a 48x96 spoil board. These "soft" limits will keep your machine operating in this window. If you have design to cut outside this window, the machine usually won't accept the cut file and execute.

I have run my machine for weeks without turning it off and it held the soft limits the whole time.

There are many MM running without any limits or homing switches at all. It's a manual start up procedure each day with manual jogging, setting the 0,0,0 in Mach and off to cutting.

[IMMark]

Thanks Sean. I couldn't find where to set the table size in Mach. That is what I meant by should have been spending more time learning the software (but I am reading about that now). And of course working on the tool holder so that I can actually cut something :)
I am sure (and I would guess you are sure) that I will have more questions as I follow the learning curve!
Thanks
Mark

[dbinokc]

Congratulations on getting your machine to move. Even though I have proxies wired in, I have not enabled them in Mach3 on my machine. Just keep well away from any stops and be prepared to hit the e-stop of anything starts moving in a direction you do not expect.

I expect my cutting to be relative to a zero on the piece being cut. I do not plan to any kind of world coordinate 0 on the machine.

[IMMark]

Thanks DB.
Yeah, so far when I have been "using" the machine, my hand hasn't left the E Stop switch :D
And I go nowhere near the hard stops. After a year and a half of building it, it would kill me to break it now (depending on what could go wrong, maybe literally)!
Mark

[smreish]

oh, you won't break it.
I've hit the hard stops at 300 ipm and the motors disengaged from the rack.
No worries. Just REALLY Loud when it happens!

[KenC]

No worries Mark, I'd never hit the hard stop....

[IMMark]

I hope to follow Ken's lead and never hit the hard stops. Sean I will take your word for "Really" loud (from my hand rolling the machine, I can imagine it is)!
I have been playing with Mach3 and some CAD software, starting to get the feel for things (I think). I am getting some nice drawings (I made a sharpie holder). I am working on the tool holder now (and considering a spindle as well).
Mark

[IMMark]

Ok, I have been spending some time looking into spindles. Any thoughts on specs?
Air cooled versus water cooled. Size of collet? Watt/HP? Also, just FYI...I am not looking at the $1000 plus spindles. I am more in the range of $600-$800 including the VFD.
Also, if you have any thoughts on vendors?
Thanks
Mark

[dbinokc]

I bought my water cooled 2.2KW spindle/VFD combo from qiandingzhensatisfaction on ebay. Ships from the US and cost $350. The included collets are metric, so you will need to buy inch ER20 collets separately if using inch bits. Both spindle and VFD are working well so far.

The motor mount I purchased from wfyb on ebay. The motor mount is just a big hunk of aluminum and some mods may need to be made to get it to fit on the Z-axes on our machines. You can check out my build thread for details on that.

[KenC]

Water cool VS Air cool
Air-cool :-
1) noisier (but nothing beat the cutting noise so its not much of a concern in real life)
2) Larger (but does it really matters?)
3) rectangle body makes, can direct mount onto the Z-slide
4) some concern with the air flow, some say it will blow up the dust.
5) usually come with 18,000rpm max

Water-cooled
1) quiet, it purr like an humming bird when not cutting.
2) water pump do seize up if left idle for a few months.
3) the spindle never gets warm,
4) the water tube is almost maintenance-free
5) almost always comes with round body which require a holder for mounting.
6) usually comes with 24,000rpm max.

[pblackburn]

Mark,
The spindle is the lifeblood of the machine. The VFD is the heart. An inexpensive heart with good blood is still bad. Just saying. Buy a chinese spindle and a good VFD, the return on investment is worth it. I am a water cooled user so I am biased. I will offer you one test scenario. You have a fan cooled motor and a water cooled motor. Using something other than your hand, toss a hand full of dust at the cutter while it is on. The fan cooled will make a plum of dust whereas the water cooled will only elevate the dust the cutter touches. Forced air from a fan will take away from your dust collection. Vacuum is hard enough to maintain let alone having to deal with a constant stream of air moving in. Try to pick up a pile of dust with a vacuum and then with an air nozzle. Which disperses faster. The air nozzle will always win. So knowing this, I vote water cooled.

[darren salyer]

Great reasoning Pete.

[Alan_c]

Actually I have found the the slight stream of air coming through the spindle will actually help with the dust pick-up as it knocks it free from the surface and allows the vacuum stream to catch it - sort of like an air stripper on a belt sander - having a skirt does make all the difference though.

[IMMark]

Thanks DB, Ken, Pete and Alan...very nice write ups, and I appreciate all of the input!
I wonder if there should be a Spindle category in the forum?
Also to Pete, I agree completely on the cheaper spindle and buying a better VFD. I have a Teco on my mill for quite some time, and really like it. I am working on the mount for my router (so I can make something with this big blue monster), but I am sure a spindle is in my near future. Off hand, does anyone know what all is needed. I think the spindle, the VFD, if water cooled; then also a pump and water reservoir, and I am using the PMDX-126 BoB...so the PMDX-107 to control it too? Do I have the correct?
Thanks
Mark

[dbinokc]

There is a section under Toolheads that covers some spindle info and also routers. Also lots of spindle info in the threads. Just do a search.
I have a PMDX-107 for my machine, but have not hooked it up yet. The 107 is not required though. I can control the start, stop and speed from the panel of the VFD I have. I am in the process of hooking up the 107.

[pblackburn]

I used modbus only. So in that case only the spindle, vfd and RS232 to 485 converter.

[IMMark]

Thanks DB and Pete...I will be doing more reading on the 107 and modbus (I think the PMDX-126 is compatible with it as well)? I swear, I can't wait until I can slow down on reading and learning new software and just make something...anything....I would be happy cutting a flat board out of another flat board :D
Mark

[pblackburn]

If you use modbus make sure that the VFD you have is modbus capable. It is a learning curve in itself. Telling you how to hook it up is another thing all together. Every VFD has different settings but most here can help you in some fashion. The $4 converter is definitely cheaper than the 107 plus modbus has been around since the 60's and is well established.

[IMMark]

Pete,
I am not too familiar with modbus (if I try to research one more thing before I get the MM cutting, I think my head will explode) :o
Like I said in my other post, I have a Teco vfd and have been very happy with it. I would most likely go with the FM50-203-C, it is sold through Factorymation. I looked at the data sheet for it, but couldn't find any mention of modbus compatibility? Would you have any idea if it would be a match?
Link for it is here; http://www.factorymation.com/Products/FM50_230V/FM50-203-C.html

Thanks
Mark

[racedirector]

Mark, if you are buying a VFD specifically for the machine I would look at Hitachi. I have an X200 but the SJ200 is a better bet. They are fully Modbus aware and there is plenty around on connecting them to Mach3.

[pblackburn]

It appears the one model has an add on module. I agree with Bruce and go with a Hitachi or Delta. I personally have a Hitachi WJ200 series. It is a very nice unit indeed.

[racedirector]

Brainfade this morning, no morning coffee when typing. WJ200 was what I was thinking of Pete, would buy one today if I didn't have the X200.

[IMMark]

Well I am happy and excited to ask for my official MechMate number!
But first, I would like to thank Gerald for starting this project and so freely sharing it with (literally the world). I also thank Mike for continuing to support this forum and supplying many of the much needed parts for the build. I also thank each build that has come before mine and everyone that has posted information, thoughts, ideas and encouragement. I also very much thank my good friend David for his role in this build and to Sean for taking his time and helping offline when it was needed.

The machine build was started in Feb. 2013 (although, the idea, research, and much reading started long before that). I am not sure what the end date should be, as I will be adding "accessories" and fine tuning things for years to come. But for me the "Born on date" will be April 29, 2014 ....that is when she started moving. The material size is 5' x 10'. I have the 14" Z, and the most notably feature is the removable cross supports (7 of the 9), that will allow the addition of the supersize Z (36" plus). And I call her, Big Blue.

Thanks
Mark


http://s255.photobucket.com/user/immark/slideshow/

[IMMark]

<a href="http://s255.photobucket.com/user/immark/media/DSCF0612_zps1e430d00.jpg.html" target="_blank"><img src="http://i255.photobucket.com/albums/hh123/immark/DSCF0612_zps1e430d00.jpg" border="0" alt="Inside Control Box photo DSCF0612_zps1e430d00.jpg"/></a>

[IMMark]

Well, that didn't go well :o
The pictures seem to open up fine in a new tab. Let me know if I need to do something another way?
Also, sorry for poor pictures and messy shop. I recently have been moving things around since a 75 square foot chunk of space just got occupied :)
Mark

[rcboats1]

Looking good.

Use the insert image button and paste the URL in the popup box.

http://i255.photobucket.com/albums/hh123/immark/DSCF0611_zps3e9e1977.jpg

[IMMark]

Thanks Kelly...the help continues :)

[IMMark]

Just in case video proof is needed....
https://www.youtube.com/watch?v=tHq9i3OI5ho

Again, apologies for poor video skills and messy shop (work in progress).

Mark

[dbinokc]

Looks good. Congrats on the successful build and cut.

[jhiggins7]

Nice going Mark. Looks like Serial Number time.:)

[IMMark]

Thanks DB & John....already life this machine, and I feel like I am just scratching the surface!
Mark

[parrulho]

Well done Mark, nice machine. Good luck!

[IMMark]

Thank you Paulo...I can't wait to put a number after my name :cool:
Mark

[Tom Ayres]

It magically appears, congrats!

[IMMark]

Thanks Tom...no number yet, but I check back frequently :)
By the way, did you change the thread heading? I've wanted to do that for quite some time (I have been finished with X rail and gantry questions for a while)?
Mark

[Tom Ayres]

No, you crazy? they'd never give me admin access! Good thing too, I'd have titles with no relevance.

[IMMark]

That's weird...someone just changed it...but no number yet?
I think they should give you admin access for a day, that could turn out interesting?
And to answer your question, nope not crazy...my parents have had me tested many times...I don't meet the criteria :p
Mark

[lonestaral]

Congratulations #119.
Welcome to a new world.:)

[MetalHead]

Mark Congrats on your build !!! You get #119.

[dbinokc]

Congrats on getting your number. Obviously getting the machine working is the most important part, but the serial number brings a sense of closure. Of course the real work now begins!

[IMMark]

Woo Hoo...One One Niner!
Thanks...feel like I get to sit at the big boy table now :)

[Tom Ayres]

The few, the proud, the numbered...:D

[pblackburn]

Congratulations on your machine number and first step. We look forward to seeing what you bring to the table. Great Job!!!!

[darren salyer]

Congrats to #119 from #101. Well Done, Sir!!

[jhiggins7]

Congratulations, Mark, on completing your MechMate and earning Serial #119.

Here's is the Updated Builder's Log (https://docs.google.com/spreadsheet/ccc?key=0AttqjIPMBEXKcExveGc4d3U0V25zQmMyX1U1eUVhU Xc&usp=sharing)with your entry added.

Please let me know the cutting dimensions of your MechMate for the Builder's Log. Also, please review your entry and let me know any changes you want to make.

[darren salyer]

So how cool is it that #26 is still an active forum member?

[hennie]

The first MM with red GT stripes:)

[IMMark]

Thank you, it's been a long road. It is nice to see the first builds are still hanging around the forum.
John, I will send you apm for the build log. I will post some of my projects....most likely will make some lady bugs...I hear good things about them:)
Mark
One One Niner

[lonestaral]

Lady bugs are o.k.
A gear, now that is something else eh Darren.:D

[darren salyer]

Sure thing, Al.
If there were a "truth in thread titles" law, we would all probably share my thread title.
I'm still having fun.

[KenC]

GEARS!!! Must cut some gears! :cool:

[darren salyer]

You guys making fun of me.......??

[IMMark]

Would anyone care to share anything on how they charge for CNC services?
I am assuming hourly for actual cutting time, setup charge, design charge hourly?
From what little I can find, looks like $50/hour on the very low end to $150 and more...
I know there are a ton of factors (and I am looking in the US).
Mark

[smreish]

Mark,
This has been reviewed before, and as your aware, the market will bear what it will bear.

I know some locally charge the following:
- 50$ a run hour + setup
- per part (negotiated)
- per design run. For instance, I cut out 100 "flower motifs of MDF"....that was 150.00

Nominal charges on each job - required.
- client provide material
- tooling charge (cost as-is per required to cut if something other than standard 1/4" carbide run-of-the-mill bit.)
- CAD/CAM drafting time if part wasn't in a good DXF or other easy to toolpath file.
.....

Or, "yeah - I can do that for 300 bucks....you have a drawing?"

[domino11]

Congrats Mark! :)

[pblackburn]

A quick way is to figure the price per square foot. I have talked to a lot of people that do it this way. If 3D is including that is another added price per sq ft. Remember you are making something custom and not a production run. Runs have different prices as first time development cost then cost per part. Everything Sean said is pertinent also. Do not be afraid to charge enough for the product. Make sure you have included all applicable charges including tooling wear cost and electricity usage. If you make a great product, people will pay even if it is a little high.

[IMMark]

Thanks Heath!
Thanks Sean and Pete...that gives me a good place to start, and that's what I was looking for. I am sure there is a bit of a learning curve there as well, but I will get it figured out.
Thanks again for weighing in.
Mark

[dbinokc]

There are plenty of opportunities to do things that can help build experience. I made a little plaque for a departing coworker a few weeks ago. I wish it could have turned out better, but she was quite thrilled and moved by it. It was a great way to start getting familiar with my new machine.

[smreish]

3D...Pete....that reminds me.
I did some statues a few years ago on the modified #5....I charged about 80 hrs to cut those.

[IMMark]

Thanks Sean, I knew that 3D would have an upcharge on it.
And DB, I can assure you that everyone that I know will be getting some kind of sign. Those that don't want one, will be getting one that says "here is the sign you didn't want" :D
Mark

[smreish]

To be fair on the statues.
Client provided NURBS based modeling scans in 3 formats to me.

16 hours was drafting, 3d model manipulation and input into RHINO and Cut3d. Amazingly, Cut3d did a better job handling the models that Rhino with 4th axis module.
8 hours set up on the machine
8 hours of test cuts
4 hours of cleaning
~36 hours of continuous cutting with 600$ worth of cutters.
...and A LOT of coffee :)

[dbinokc]

Were the cutters special or basic carbide?

[smreish]

The first round of cutters were from:

http://www.3dcutting.com/solutions/frogtools.html

the 12" cutter is about 280.00 US.
I had 3 other specialty tapered ones for this project.

I did find out that with a little bit of experimenting on the bench grinder, I was able to make my own bullnose and 45"/60" degree point long cutters from off-the-shelf 1/2" drill bits at home depot. The trick was grinding them so they were balanced.

I used the drill bits in a Large drill press, hand grinder in a machinist vise and radiused them while in rotation at slow speed. Then resharpened afterwards. Perfect for foam cutting at 13K RPM.

Good luck.

[IMMark]

I was looking into to some HDU and found some 15lb, 4x8- 0.75 for about $200 delivered.
Is that about what you guys are used to?
Mark

[darren salyer]

Sounds about right, but I wouldn't get it unless you need it specifically......
I use Azek PVC from Home Depot at $100 for a 4x8 1/2" sheet for exterior stuff.

[IMMark]

1/2 the price and on the up hill side of the learning curve...I am in!
Thanks
Mark

[IMMark]

Extra benefit from Big Blue. In a 1-man shop, it has always been a PITA to crosscut long wide sheets on the table saw (my rip-fence is 52" max). I had a part I needed to cut crosscut at 61", I clamped it down on BB and she did the job ...much safer too! Just saying, yet another reason no shop should be without a MM :)
Mark

[IMMark]

Just FYI, these are on sale on ePay...10 round nose 1/8" for $16.79 shipped. No idea if they are total crap, but for $1.67 a bit ...thought I would try them out. Auction number, 201104409861.

Mark

[darren salyer]

Those look like they'd be worth a shot.
Please report back with your observations.

I agree on the MM....I sometimes need to make long tapered pieces, very easy on the MM.....not so easy on a table saw...

[IMMark]

Yes, Darren ...I will certainly post some feedback. I have been mostly working on the learning curve for the Mach3 and CAD. Just some very small and simple projects to get my feet wet, but lots of fun. I actually am just going to surface the whole machine for the first time (until now, small projects have been done on a temp sacrificial board).
I am curious how others have done that? I still have my router set up (the spindle is planned for the near future). So my PC router is limited to a low end RPM of 10,000.
I have Grizzly Fly cutter set (for my mill) but I am sure that even at 10K that is too fast for them? Is my best option just a 1/2" end mill? And if so, what is the fastest feedrate I could use? My spoilboard is 1/2" MDF (over 3/4" MDF support board, table size is 5x10).
Thanks for any input!
Mark

[darren salyer]

150-200 IPM should be fine. The biggest end mill at about 80% stepover would be good.
Obviously you want to remove as little as possible, so a little time finding the low point on the table and going a few thousandths below that is a good plan of attack.

[pblackburn]

I ran a 1 1/2" double flute to surface mine at 80ipm at 12k rpm.

[KenC]

Do very light cuts. start with 1～1.5mm & increase if you think your router can handle it.

[IMMark]

Thanks for the input, biggest endmill that I have that will fit the 1/2" collet is a 1/2". With the 80 stepover /200 ipm on a 5x10 table, that is just over 3 hours. That is like watching paint dry! (At least compared to the short runs I have been doing). Pete, when you say 1 1/2" double flute, is that the length or width? The Fly cutters that I have are like this;
http://www.grizzly.com/products/Fly-Cutter-Set-w-Tool-Bits-1-2-/H5935

I would think with the off-balance design, at 10K that would be too fast? If not, even the small one would cut my time by triple.
Mark

[Alan_c]

You are looking for something like this: https://www.magnate.net/ProductDetails.asp?ProductCode=PG136
available from 3/4 diam to 2 3/4 diam.
That fly cutter is NOT suitable for use in the router, it's meant to be used on a milling machine.

[Alan_c]

and another one from Amana tool: http://www.amanatool.com/cncroutingdetails/rc-2252.html

[IMMark]

Alan...that is what I thought...I didn't think the Fly cutter could handle those RPM's.
Thanks too for the links....big price difference! But I will give one of the Magnate products a try.
Thanks
Mark

[domino11]

CNC Spoilboard Surfacing Router Bits (http://www.carbideprocessors.com/router-bits/cnc-spoilboard-surfacing-router-bits/)

[IMMark]

Thanks Heath...those are very nice...but they are in the "other" price category ....
I am starting with the $30 ones :)
Mark

[domino11]

Yes I hear you on that one. You might be suprised at how fast those
$30 cutters dull on mdf though. :)

[IMMark]

Oh I know I am getting a $30 bit, at least it is carbide. And I can certainly see (I hope) at time when I am running enough jobs and profit that one with insert cutters will be the way to go. Until that time, this will be a big step up from a 1/2" HSS endmill :)
Mark

[KenC]

Any cheap router bits will do the job.
Also, nothing stay sharp forever when cutting MDF.

[racedirector]

I can atest to that Ken. I bought one of these off ebay: http://www.ebay.com.au/itm/131088061160?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649 and the last time I used it to surface my old machine machine it left burn marks all over the place. I had maybe used it 3 or 4 times on a 1200x1200 spoilboard.

[ger21]

With a 1-1/2", 2 flute carbide tipped router bit, try removing .01"-.03" per pass, at about 14,000 rpm and 300 ipm, with a stepover of about 1-1/4".

[IMMark]

Thanks for the input. Ger, I will give that a try (when the bit arrives). Just did the toolpath for it, 40:40 ....sounds a lot better than the nearly 3 hours I was looking at :)
I will let everyone know how things turn out.
Mark

[pblackburn]

I would not use a fly cutter. Insert type would be the best, I use a Freud bit 12-190. Ger mentioned something I did not, I remove 0.025" at each re-surface. MDF is all about the correct feed/speed. It takes about 40 minutes to complete at 80ipm. If I used Ger settings it would be around 15 minutes. You will know it you push too hard or too slow, MDF has a distinct burning smell when you are over or under the cutting speed/feed even when burn marks are not on the material.

[IMMark]

Hi Pete
My table size is 5x10, I am surfacing at 120"x 61". So may take a bit longer than a 4x8. But I will certainly keep smelling for an incorrect feedrate!
I wonder if the Fly cutter would be ok with a spindle/VFD set up?
Mark

[smreish]

Also, be mindful that if you surface to fast, the leading edge of the large cutter with scallop the table and may leave a less-than-flat table. I found this true with my router set up..not so much with the spindle....but happened.

[IMMark]

Thanks Sean...there should be a whole section on just spoilboards :D
Mark

[pblackburn]

The limiting factor (in my opinion) with the fly cutter is it requires a solid machine made for machining metal. The bearings in a spindle are a high speed, high precision bearing the same as a mill spindle. However, a most mills spin a maximum of 2400 rpm. A well built mill as other factors that make it suitable for offset cutters where this machine is not. The spindle in a mill is housed in a block of steel or bored into casting for the head. The clearance is usually 0.0005" or less. The head is locked down to the body of the mill. We use 6 single row bearings for the up and down of the Z with only the V groove holding it in. Even if you have linear bearings they are designed for compression loads and not extreme dynamic forces like you receive from a fly cutter. With the speed it would be turning at I would stick to tooling designed for wood routing.

[IMMark]

Thanks Pete...that makes a lot of sense. I will be using the 2 flute 1 1/2" for now. When I can upgrade to a spindle and a surfacing cutter with inserts, that's the way I will go.
Pete, I also may be contacting you (if you don't mind) when I am moving on the VFD, I think the Hitachi WJ200 that you mentioned earlier sounds like the way to go. But may have some questions on the set up etc?
Mark

[pblackburn]

No problem if you need to.

[IMMark]

Thank you Pete! I tell ya...if I put one more thing on my tech plate, my head is going to explode!!! Just to give you an idea, right now I am working on of course learning the Mach3 and CAD for MM, building 4 MAME machines (really cool project if you aren't familiar, for those of us of a certain age), a kiosk built around the Raspberry Pi (Linux based system), down-grading a laptop that is pre-loaded with Win8 to Win7 (those that don't know, Win8 basically locks you out of doing that with loading prior to hitting the "hard drive", BIOS is gone and is now UEFI...just terrible to deal with. And finally my wife has her first smart phone...and though I love her dearly...she is perhaps one of the least techie people on earth :)
So again, thanks for the offer!
Mark

[pblackburn]

I can't say anything about the smartphone, all mine are dumb indeed however my wife wants one now. I am terribly hard on cell phones, tend to break even the brick style ones(literally crack, smash or shatter) all while in my pocket. So for financial reasons, I have never purchased one. With your MAME are they all one station or vary?

[IMMark]

Yep, that's exactly why I keep it out of my pocket while in the shop...always hitting on something. The MAMEs are all individual and identical. I had told a few friends that I would make them, once I had the MM to do it on.
Mark

[barry99705]

Thank you Pete! I tell ya...if I put one more thing on my tech plate, my head is going to explode!!! Just to give you an idea, right now I am working on of course learning the Mach3 and CAD for MM, building 4 MAME machines (really cool project if you aren't familiar, for those of us of a certain age), a kiosk built around the Raspberry Pi (Linux based system), down-grading a laptop that is pre-loaded with Win8 to Win7 (those that don't know, Win8 basically locks you out of doing that with loading prior to hitting the "hard drive", BIOS is gone and is now UEFI...just terrible to deal with. And finally my wife has her first smart phone...and though I love her dearly...she is perhaps one of the least techie people on earth :)
So again, thanks for the offer!
Mark

Depending on who made the laptop, you should be able to disable secure boot in uefi. My Dell XPS12 came with windows 8 and I had Debian running on it for a while. Went back to 8 until they get the touch drivers worked out. Most current linux distributions support efi, and so will windows 7.

[IMMark]

Yes, I went with a Dell. Started with Asus, but there was no way to boot from dvd or usb (even with secure boot disabled) Dell states, as long as it is preliaded with Win8 pro, you can down grade to 7.
Just got it today, haven't had a try at it yet.
Just learned about Debian working with Raspberry Pi.
Mark

[IMMark]

Quick question on tabs. How many and size? Take for example, 3/4" sheet , cutting several 1.250" holes. How many tabs per hole and what length and thickness would you use? I did a practice part...and took a lot of work to get the holes smooth. I think I used too many and too large?
Thanks
Mark

[darren salyer]

I'd do no more than 3.
.375 should be plenty big.
Have you tried 3-d tabs?

[pblackburn]

Depends on how flat you sheets lay. I have used only 0.080" thick at 0.438 length before but others I have used 0.11 thick. I have used both 3D and standard tabs. Generally I only use 3 on circles unless they are over 12" diameter.

[KenC]

I just leace 0.1~0.2mm onion skin on, not cutting through. the skin will tear off very easily & sanding will be minimum. Since no matter how you do it, you will have to SAND.

[IMMark]

Thanks for the input...I am afraid that I don't know what standard tabs vs. 3D tabs are?
Mark

[smreish]

Mark.
A standard tab is a flat, single height tab that is like a rectangular block.
A 3d tab has a ramp on the lead in and lead out of the block to minimize the about of material to be removed but laterally long enough to keep the part from shifting.

....think dinner plate vs. upside down bowl.

[IMMark]

Got it (I think) so, as long as it is strong enough to hold....I guess a 3D would be preferable? Also (I know Google is my friend) so I searched, I guess this is an example of a 3D tab? ; http://www.wired.com/2012/10/you-suck-at-using-a-cnc-router/holding_tab_cut/

Mark

[darren salyer]

Yes, that's a 3-d tab.

[Andrew_standen]

I am a bit late on reading this thread.
I run a 2.2kw water cooled spindle.
I skim my board ( 2440 by 1220 ) with a 40mm dia cutter. 9000 rpm 7500mm feed rate 1mm depth of cut. Sure makes a lot of dust if the extract is not switched on. ...lol
I use 3d tabs 90 percent of the time. 5 percent is onion skinned. 5 percent i forget and make a right mess of things ...
Cheers Andrew

[IMMark]

Wasn't really sure where to put this post...so I thought I would throw it on my build thread.
Does anyone here know jhiggins7 (John #26)? I haven't heard from him and have not seen any posts from him in quite some time. Just hoping he is ok?
He helped me out with a project awhile ago and wanted to let him know how it all turned out.
Thanks
Mark

[domino11]

His last activity on the board was today. Have you tried sending him a PM?

[IMMark]

Yes, glad to report that I have heard from John. Sounds like he is doing well.
Mark

[IMMark]

Looking for any advice!
I have to make some parts, 1 1/4" to 1 1/2" thick. I can use plywood, pine, mdf or really most anything paintable. I have some 1 1/4" mdf, but not loving it. Tons of dust, hard on bits (unless I am doing something wrong)? Of course I want to use least expensive material, do as fast as possible, etc. I could use standard construction grade 2x6's, knots and edge finish is not important. Any thoughts, on material and corresponding bit size, speed and feeds would be greatly appreciated!
Thanks
Mark

[pblackburn]

Use the chipload for the type of material from the manufacturer and start by using the calculated lower end feed and adjust acoordingly. My preference is solid carbide bits or carbide insert that are brazed on. It does not need to be a top of line bit but better than your El cheapo ones. MDF is dusty but you should be getting descent sized chips and not dust, if not, the dust will wear down the cutting edge. That is true for all cutting. That being said, MDF will have a shorter tool life but you could always use a burr bit, as some guys have reported good results with those. As far as what to use, indoor, outdoor, stability, longevity, 2D, 3D. .. you need to take all into account and go from there. You do not have any of that listed so we would not be able to answer you.

[IMMark]

Thanks Pete
I have not worked much at all with MDF. I am getting mostly dust, not chips? I was cutting 3/4" MDF, using a Whiteside 1/2", up/down compression bit (can't find any info on chip load). I was cutting at 16,000 RPM, feed at 100 ipm, 0.220 depth per cut. Any thoughts on that, perhaps to slow on the feed?
This is an indoor project, making craft angels. Pretty simple cut out shape that is getting painted. I suggesed MDF thinking it would be easy to paint, but not having worked with it (except for just some basic cutting on a table saw). Perhaps using 2x pine would be a better choice (unless, I can get the MDF going)? The old supplier for this passed away, and I am sure was using 2x pine cut out on a band saw. Also FYI, I have a router (no spindle yet) , RPM range of 10,000 to 23,500.
Thanks for any input.
Mark

[pblackburn]

Now this will not be exact for your bit but they have an up down spiral which is the 60-100 series I believe. Double check it, don't take my word for it.

http://www.onsrud.com/xdoc/feedspeeds

Using the formula they give and like I said start at the lower end is best. Another thing to notice is the temperature of your cutter after the cut. If it is more than warm to the touch (a little above room temperature), your feed/speed is wrong. The heat should go into the material being removed and not the cutter. I don't usually go over 12k RPM with MDF but it is all about the machine so others may be able to run faster and not have chatter on their parts because of the rigidity of the machine and quality of the bit.

A lot of people think run the speed faster and the machine slower is conservative but it will destroy a bit as fast as speed too slow and machine too fast. It all has to match.

You will find that with chipload or IPT (inches per tooth) that most manufacturers don't give them. So once you find a good chipload and long tool life for that tool, be sure to write it down. You can always call the manufacturer and ask for the chipload.

Pine probably would be fine but remember it does like to cup as it dries out. Try one and see how it goes. I hope this helps you in some way and I am sure others will give their advice as well.

[IMMark]

I took a look at that, Thanks!
If I have this correct, running 12K rpm, with 2 cutting edges, and a chip load of .016; would give me a feed rate of 384 ipm? Do you agree with that? Also, if that is correct...my feed rate was way to slow at 100 ipm. I have never run anything near that fast, that is why I am just double checking!
Thanks again for the input!
Mark

[IMMark]

Also, it states 1x D, so with a 1/2" bit, I should be taking 1/2" per pass?

[pblackburn]

It would appear you had a 0.004" chipload with the speeds you were running. I would start with 0.08 - 0.012" and go from there. Try 10k RPM and 180IPM. That would be a starting point. Depth of cut would depend on the tool but I would start with no more than 1/2 of the diameter while testing. This is an assumption but I think most Mechmates are not run that fast and doubt if it would render a good finish cut. I have run 240IPM before but I am selective on the speed based on the material and bit.

[pblackburn]

Remember these are calculations and will have to be run adjusted. They normally say with the calculated to start with 70% for the feed. So if your feed is to be for example 200IPM then either start with the g code set to 140IPM or set your feedrate override to 70% before starting. If you have a good bit you trust, you could start with full pass depth of 1/2". But don't jump in whole hog, test and inspect, modify and test, modify and test. Once you see the finish deteriorate or the bit too hot then back off to the previous setting.

[IMMark]

Thanks Pete, that was very helpful. I am over 200 ipm with good results and making chips instead of powder :o

I appreciate your feedback!
Mark

[IMMark]

Well my bit is getting hot after 15 mins of cutting. My router will only go down to 10K, so is my only other option to keep raising the feed rate? If so, than is this an example of where a spindle is better than a router (being able to get lower RPM's)?
Mark

[pblackburn]

You could use air assist cooling but only if you have adequate dust collection. It does take a lot of air just a trickle or break up your continuous run to give a little cool down time.

[IMMark]

ok, I can break up the number of parts into smaller runs and get through this job. Do you know, if I am correct about my logic on the spindle vs. router? Wouldn't mind "to have to" get a spindle :)
Thanks
Mark

[pblackburn]

You could run the spindle at 8000 or you could go to a single edge tool

[IMMark]

I am hearing that I should buy a nice new spindle for #119....I'm gonna tell my wife you said so!
Again, really appreciate your help, Pete.
Thanks
Mark

[pblackburn]

I would opt for a different tool first but if I must be the reason I can be that also.

[timberlinemd]

Even with the spindle I would go with a single flute cutter.
I would guess that some of that heat is generated by the router being run under less rpm/power, at least that is what I saw with my router when trying run in the lower speed range. A spindel will have no issues with lower speeds as long as you maintain the recommended speeds set by the manufacturer (8k min.)

[IMMark]

Thanks Steve.
I have ordered some carbide single edge,and will give that a try. I dulled what I was using, I think I was ruining the plunge rate to slow. I was goning to post and ask, when setting the feed rate, is the plunge set the same?
Mark

[timberlinemd]

<<is the plunge set the same?>>
I use a half speed on the plunge

[pblackburn]

I normally ramp in and rarely plunge as the bearings are not really set for an axial load but rather for a radial load. If you do plunge and do not know how the bit will behave start at 15 to 30 and listen to the process. If it is too aggressive, you will hear it. If not, you can increase it.

[IMMark]

Thanks, I will do some experimenting on plunge rates and ramping.
But that gives me a starting point.
Thanks again
Mark