Video, Logos and DUST! #87 - Suwanee, GA [Archive]

docarter

Sun 22 March 2009, 15:37

Hello everybody,

I've been reading this forum for months. I first like to salute Gerald on this forum and to everyone who share their building experiences and knowledge:) This is not a forum but a community. It is my goal to build a table 49" X 97" and I plan to share the entire painful experience.

I am out of Atlanta, Georgia and vendor resources are great here. However I am a women, so I am sure I've got other challages. My Budget is $6000.00 and I have already spend to much money to have not started anything:eek: I am in the utility business so I am sure I will have resources available to build the structural portion.

I have read almost every entry in this forum and will be going back reviewing several of my journey. I have found a local steel vendor who appears to have the best price in the area and can deliver within 24 hours.

Below outlines what I have already order:

(1) Grinder (I have the patience job. Slow Slow Slow)

(1) SteelSaw (Using to cut down rails w/guide on both sides)

(4) OM PK296A2A-SG7.2 (Received in: 4 Day)

(4) G203V (Standard)

(1) Laser Parts - Joe (Received Next Day :cool: He's good!)

(1) Breakout Board (PMDX-122)

(1) Computer (Already Have)

(1) Mach3

I try to organized and hope that everyone who read this will give me feedback.

Gerald, I have organized your drawing by there sub-assembiles (have questions). I will reformat and post.

Jayson

Sun 22 March 2009, 17:39

Welcome to the community,

I look forward to reading all about your build.
I see no reason that you would experience any challenges different to anyone else here, and I am sure any challenges encountered will be overcome.

Good Luck.

Jayson.

bradm

Sun 22 March 2009, 17:52

Welcome! Some of the better welders I know are female; you might just have an advantage.

As I have a rather, "compact" frame, I found one of the more interesting and satisfying aspects of my build to be using brains rather than brawn to deal with some of the material handling and moving challenges.

I'm sure you'll do just fine, and have a great time along the way.

docarter

Sun 22 March 2009, 18:13

Gerald, I have reorganized your drawing by sub-assemblies and I can not find any drawings labeled 50-ToolHolder in your new released.

I also have the questions on the steel:
1. Would like to use 3X2X1/4 where C3 are outlined.
2. Would like to use 3x3x1/4 as post.

I am in the process of bill a material list and would to make some changes.

Rad Racer

Sun 22 March 2009, 19:39

Welcome, I look forward to your build. Be sure to give a shout if you hit a snag.....there are many excellent builders on this site that are always willing to help.

Remember to stop and take a few photo's from time to time.

Good luck.

Gerald D

Sun 22 March 2009, 21:00

Welcome Ladieswork. You have caught me at a bad time to check on alternative steel etc. - I am off to Malaysia in a few hours time and I won't have access to my reference books and drawings for a week.

Gerald D

Sun 22 March 2009, 22:53

I can not find any drawings labeled 50-ToolHolder in your new released.

I also have the questions on the steel:
1. Would like to use 3X2X1/4 where C3 are outlined.
2. Would like to use 3x3x1/4 as post.

I have never published drawings for 50-Toolholders. I am not familiar with the tools in use over there.

What is "C3"? I don't know the term and I can't remember using it on a drawing. Maybe my old age is catching up . . . . .

"3x3x1/4 as post" If you are talking of the vertical legs, then 3x3x1/4" angle iron will work. 3x3x1/4" square tube will also work. Don't know which section you are talking about?

docarter

Tue 24 March 2009, 16:13

I also like to thanks everyone who responded wishing me luck, I'm going to need it.

Gerald,

I have been shopping around for surplus steel since my last posting. Even though we are in a recession here, high rise construction is still going on. So I decided to drive to a couple of sites and ask if they have any surplus steel. What a good idea this turn out to be:D I was able to found enough steel to complete the base table and gantry. Some of the items are not the same as your drawing (larger), but will work. My total cost for steel is $135.75 and I had to pick it up. With the use of a company vehicle I'm in business.

Will do a drawing tonight and try to post it tomorrow.

I've ordered some additional items.
Superior Steel (Mechmate Kit) from Rick:
GW3X = $14.49ea @ 14pcs = $202.86
B3X = $2.91ea @ 6pcs = $17.46
Shipping by UPS Ground to 30024 Residential = $11.86
Total = $232.18

Milwaukee 5625-20 -ebay $225.00
Router Mount - ebay $60.00

I'm also going to complete my calculation tonight so I can start my kitchen project.

I traded my programming skill with a friend for some licensed welding services:) He was laid off and now is working for himself. So I will build him a web page with paypal, email and private customer areas.

I think I am going to be busy this weekend.

Jay W

Thu 26 March 2009, 05:33

Good to see another Atlantan joining in the Mechmate addiction. Welcome and looking forward to your build.

Jay

blurrycustoms

Thu 26 March 2009, 09:49

Sounds like you have all the drive you will need to complete this project within your budget goals, especially in taking the time to shop around for surplus steel and such. I don't expect that you will meet any challenges that you can't overcome. Good luck on your build.

Fronzel

Thu 26 March 2009, 14:25

I'm in Atlanta too.

I got the parts from Joe. My next step is getting a welding machine, I've not even looked to see where I can get steel.

I didn't think about visiting construction sites for cut offs. That is a good idea.

docarter

Thu 26 March 2009, 19:04

Thanks for the support guys, I'm glad to know that I have some local help. I'm very excited to get started. I'm sure that sounds crazy coming from a women, but I need this machine to have the freedom to prototype my design ideas. I know I said that I traded skills for welding, but my husband wants to complete all of the welding himself:D He is more excited than me, I believe he has his own plans:eek: This is going to be interesting.

I'm in the process of making room in our basement for this project. My entire basement is pack with tools and I need my garage for cars. Our basement ceiling height is 9' and it has a large walk out. I will start posting pictures of everything purchased in the morning as I relocate them.

docarter

Fri 27 March 2009, 18:22

Okay, I finally found my camera cord so that I can begin to add pictures. I have read almost this entire forum and one thing that really concerned my was the rails. As a result, I went ebay shopping for a metal saw & grinder. I found the following:

New SteelSaw 7" @ $140.00 including shipping

4184

New Grinder @ $40.00

4185

docarter

Fri 27 March 2009, 18:51

It is raining here, so I think I'm going to waiting on start the table. I have received my package from Joe. His service was next day and the part are excellent. I also received my package from Rick @ superior bearing. Rick's service was excellent as well and quick. This forum has great responses, but it is alot of reading.

4186

4187

Gerald D

Fri 27 March 2009, 20:51

Hi Ladieswork, (how about a simpler name? :))

To attach a picture inside the post, use the paperclip icon.

docarter

Sat 28 March 2009, 11:19

Gerald.

I had not idea where my name and location would appear. Nevertheless, with testing correction has been made.:) I use the paperclip, but I did not see it visual so I dragged it into the screen. Functionality learned, I will just use the preview post before I post. Sorry, I'm eager to get this thing cutting.

I was going to purchase locally a control box, but I still have a question. What size box do you recommend? I plan to attach the box to the machine. I also like to have a box size that has growth for another axis.

Gerald D

Sun 29 March 2009, 04:00

Hi Donna

Have used the http://www.mechmate.com/forums/images/editor/attach.gif icon on your earlier pics and centered them for you.

For a 5-drive box, you need about 22" tall, 18" wide, 8" deep. With dust gasketed door

docarter

Wed 01 April 2009, 19:20

Gerald,
I got the box, with the following size (24x16x12). I'm investigating making a change to my panel to allow for a simply sub panel upgrade (adding functionality). I don’t plan on spending much time on this. However, I've being reviewing (again) some of the other built histories to acquire lessons learned.
In that processed, I realized that I did not mention anything about my skill level. I'm an application engineer w/ISO 9000/2000 certification. I work for our local electrical company, but my skills level is computer design.
Question:
After some more reading, I’m in question of what your recommendation are for the power supply. It appears that your requirements may have changed. I’ve not decided what wiring method I plan to use. You and Mike have made several recommendations that I just want to make sure. I plan on obtaining this locally or maybe building this for cost reason (free materials).
What are your recommendations for a power supply with the following components?
Oriental Motors - PK296A2A-SG7.2
Gecko Controllers – G203V (Standard)
Breakout Board - PMDX-122

Gerald D

Wed 01 April 2009, 20:39

Hi Donna

My personal approach to a power supply for that choice of motors/geckos/PMDX is to build my own supply with a transformer, rectifier and diode. I am not impressed by the ready-built supplies available in your market, though I might suggest them from time to time for someone who is unsure about their ability to connect a transformer to a rectifier and capacitor. Seems like you will be comfortable to build your own?

I use a 300VA transformer at 28 to 30VAC output. Many others will use a bigger 500VA transformer instead - not much more expensive. Mike recommends around 24V, he likes cooler motors - I like the extra torque from the warmer motors.

We have the luxury of getting transformers made to order. We have another small coil put on the transformer for the 9V AC output to the PMDX. However, it is very simple to add that coil to the transformer yourself. This DIY extra coil has appeared in MM'ers photos without incident or discussion.

Too many words have been written on the power supply issue - it is a simpler subject than what it appears to be. :)

Richards

Wed 01 April 2009, 21:55

The PK296A2A-SGxx motor has a triple personality. If you look closely at the data sheets for the PK296-03A and the PK296-F4.5 motors, you will notice that all three have identical electrical specs (unipolar). You will also note that the PK296A2A-SGxx motor is rated at 3A while the other two motors are rated at 4.5A That is probably because of the gearbox. The SG7.2 gearbox is limited to about 700 oz*in of holding torque, but the motor, if attached to a huge gearbox, could produce about 2,000 oz*in of torque (at 7.2:1).

What I'm getting at is that the 32 X SQRT(Inductance) formula that Marris published for determining the maximum voltage expects that we're going to push the motors as hard as we can, but driving a motor at 3A instead of at 4.5A means that it will run much cooler.

It took awhile before I finally looked at the data sheet and noticed the electrical specs for the motors. When I hooked my PK296B2A-SG3.6 motors up to a 40VDC power supply, I got cooler temperatures than I had expected, especially when I compared that motor to other motors that I tested at their maximum computed voltages. The secret seems to be the Amp rating. At 3A, the geared motors are not being pushed nearly as hard as similar motors that are allowed to pull 4.5A.

To me, that is an excellent feature. The 7.2:1 motors are reported to have plenty of torque, plenty of speed, plenty of accuracy (resolution) and as an added bonus, they run cooler - so they should last far longer than motors that are pushed to their (temperature) limit.

Like Gerald said, building a power supply is "a simpler subject than it appears to be." A low cost toroidal transformer, a bridge rectifier and some snap caps are all the pieces that are required. Anyone should be able to bore some holes with a spade bit in a piece of scrap MDF or plywood to hold three or four snap caps wired in parallel. So for $50 to $75 you could easily have a very reliable power supply.

(For a 40VDC power supply, get caps that are rated at least 50V. 63V would be better. Snap caps pack a lot of capacitance in a small package. It's not too hard to find some rated from 6,000uF to 10,000uF. You add the capacitance of all capacitors when you wire the caps in parallel, so, three or four caps should be adequate. You'll want to have at least 15,000uF to power four PK296A2A-SGxx motors. 25,000uF would be even better. I've had a lot of trouble finding good quality large caps with screw terminals. Most of the large "can type" caps with screw terminals that I have looked at recently had build dates going back to the 1970s and 1980s. Caps dry out over time. I don't like to install caps that are more than 5yrs old into new equipment.)

docarter

Thu 02 April 2009, 06:14

Guys, I think I'm going to build my own:rolleyes:. I know I can found local help at work/home if needed. I also have the equipment to test almost anything electrical.

Wish me luck, Thanks!

Gerald D

Thu 02 April 2009, 06:34

Donna, don't rely too much on luck. If you are nervous, send us some pics before you switch it ON. :)

jhiggins7

Thu 02 April 2009, 06:44

Donna,

I built my own power supplies. In my case I used a 400 VA (cost $$44) for the main power supply and a 20 VA (cost $11) for a low voltage power supply. I bought my transformers from Antek. I also wanted dual voltages. For the small power supply I generate 12 VDC (for PMDX) and 24 VDC (for low voltage control of the stop circuit, router, etc).

Jon at Antek was very helpful. He provided a circuit diagram for the dual voltage power supply.

I got 4 10,000 MF 100 V capacitors for about $10 each, including shipping, from Asia via Ebay.

I haven't noted any heat being generated by the transformers. But, I'm not in full operation yet.

You can see pictures on my thread if you'd like.

I'll be glad to help.

Regards,
John

docarter

Fri 03 April 2009, 10:56

Thanks John, I may need to ask you some question. I spoke with some of my co-workers and they all believe that this is going to be a very easy task (just a different application). They also gave me the number to our company investment recovery group.

I spoke with them and they have a lot of things I can use for the project Today, I picked up a silm steel cabinet for $5.00. This thing is very heavy. It will house a flat panel monitor, computer and the control box.

It finally stopped raining, so I know I'll be cutting this weekend. I elected to purchase the following: Main Beam and Rails from a local steel company. This table is going to be very beefy. I plan to only use 6 cross bearing. I need to complete my plans so that Gerald can give it his blessing.

jhiggins7

Mon 06 April 2009, 21:53

Donna,

Got your E-Mail. Happy to share my experiences.

I built two power supplies. I used a 400 VA toroidal transformer ($44) for the main power supply and a 20 VA toroidal transformer ($11) for a dual low voltage power supply (12 VDC for PMDX-122 & 24 VDC for the E-Stop Circuit and Router, etc. Contactors ). I got both toroidal transformers from Antek. Jon at Antek was very helpful including sending me a circuit design for the dual voltage power supply.

I shared a schematic of the Control Circuit that I used here (http://www.mechmate.com/forums/showthread.php?p=18839&postcount=18).

My Control Box layout is shown here (http://www.mechmate.com/forums/showthread.php?p=20356&postcount=24).

I bought four 10,000 MF 100 volt capacitors from Asia via Ebay for about $10 each including shipping.

I followed the experience of others on the forum and placed an order for DIN rail, connector blocks, main contactor, safety interlock switch, power on-off switch, etc. from FactoryMation. I got the plastic duct from a local supplier for about $20 including taxes.

Since I decided to use Contactors rather than SSR's to turn on and off the router, dust collector and vacuum hold-down, I purchased 3 surplus 24 VDC Contactors for about $4 each. If you decide to go with Contactors, I can point you to the supplier I used.

I placed 3 or 4 other orders with Internet suppliers for 5 volt relays, 24 volt relay, small electrolytic capacitors, two sizes of bridge rectifiers, perforated circuit boards, terminal blocks, etc.

I had some parts like the transistors for the relay control board and the fan to cool the Gecko's on-hand.

Regards,
John

jhiggins7

Wed 08 April 2009, 07:50

Donna,

I thought of another item that might help. I added an Electronics Order Spreadsheet to my thread here (http://www.mechmate.com/forums/showthread.php?t=1616). Wanted to keep everything together and not clutter your thread.

Happy building!:)

Regards,
John

docarter

Thu 09 April 2009, 16:53

John, sorry it has taken me so long to response, I had some personal issues that needed my attention (those kids). My two sons are grown but they still need guidance. They found out this week that they will have a part time job soon:D Now I am on vacation for 4 days, so I plan to work on my MM the whole time.

I really appreciate you adding the 2 links because I could have trouble putting it all together. Now it made sense and I should not have much trouble. What you added today was a bonus. I am sure there people other than me will found this helpful. I have taken David Moore’s excel sheet I found on this web site and edited for my build. I'm also making a building manual that includes everything in one place.

I have already ordered several parts and plan to pick up some locally this weekend. I also found some good web sites that I will share. I will be sharing picture soon, just want to get a little further.

docarter

Mon 20 April 2009, 18:37

Hello everyone, wanted to give everyone an update of my progress. I work for our local utility company and we are currently experiencing some bad weather. Check out the news, it has been like this for weeks. Bad weather means no fun (MM) for me. However, during my time off, I was able to gather several components for my control system and cut some steel (lower part of the table). Elected to wait to purchase the power supplies until I have purchased all of the components. I plan to stay within my budget and have a high quality ending product. This is my ISO 2008/programmer (analytical) side of my brain. I can not justify purchasing something that I'm NOT comfortable with. This means I need to do some research.

I have made another visit to our investment recovery group looking for parts. The steel from them is $0.10 a pound and I still need a main beam. This is like a weekly yard sale; one company's trash is another company's treasure. I purchased 4 industrial strength alum 4x4x1/4 post; I thought I could use them as table legs. They are heavier than the channel defined in the plan and are already threaded. I have emailed our design group and they are going to follow up with the specs.

Gerald,
What are your thoughts about using this as table legs? I will follow up with a picture, they already have welded brackets for a lathe support.

I have elected to be cheap (budget constraints) and wait. With our weather the part be become available; just looking for a straighter member.

Gerald D

Mon 20 April 2009, 23:36

The legs serve 2 main purposes . . . .

- The no-brainer purpose is to elevate the table off the floor. For that, even a 2x4 plank will do.

- But the second function is to stiffen the main beams from toppling over. Here the legs work in conjunction with the table cross-support beams 1010302, as well as vertical bearers 1010314. When taking cuts in the y-direction, there are forces which tend to topple the tops of the main beams in the y-direction. Not that there is a real risk of them ever falling over, but there is the risk of resonant vibrations reflected back as tool chatter marks on the job.

The tables I have built so far have always had the legs and vertical bearers welded to the main beams. The two tables in operation have the cross-supports welded as well. Within a few weeks we will have a table running with bolted cross-supports, but still with welded frames 1010310. So, I cannot personally vouch for the stiffness of an all-bolted construction, and more so if the bolting is to relatively flexible aluminium. My gut feel is that it would work, but I am nervous to state flat out that it is going to be good. (Those heavy main beams seam to vibrate all the same, irrespective of how I fixed them so far)

JD68

Sat 02 May 2009, 09:10

Donna,

I live about 30 minutes away and your build caught my eye.

I am anxious to get an update! :)

Continued good progress on your build.

JD

docarter

Sun 03 May 2009, 16:47

Hello JD68,

Table:
I have made some progress on my table table. I work for our local utility company and this is our busy season (storms), thus resulting in not much time to work on my MM. My steelmax saw has come to be very helpful tool. Jhiggins7 technique of guides/clamps on both side has made this very easy. All of my parts are cut, but I do not own a welder, so I will be picking this up on Tuesday.

Georgia has lot of ways to obtain steel cheat! I will be turning back in all of my aluminum in for cash:D

Control Panel:
I have order the remaining part needed and hoping to get them soon:
contactors, connection, pushbuttons.

I do plan to share picture very soon, just wanted to get more material.

sailfl

Sun 03 May 2009, 16:52

Donna,

You are making good progress and I look forward to your pictures.

docarter

Mon 08 June 2009, 18:52

Hello Guys,
I wanted to give everyone feedback on my progress. I’ve emailed some successful builder asking them to share their electrical equipment list to help give me get a better understanding. Thanks Guys! I used this list to understand how these pieces interact and investigate how to incorporate my own features. When I don’t understand, I can’t justify spending money.
With that said, I elected to use to following in my build:
Power Supply Requirement:
Pro:
PMDX-135-8020:
Reasoning; Swappable Transformers to support upgrading.
12VDC AC/DC Din Rail Power Supply
Reasoning: PMDX122, Proximities Switches, Relay Board
Con:
It is very hard to find up-to-date capacitors to meet all of the about requirements. I just needed to more on.

In my next picture post, I plan to share my thoughts on steel, table & welder. If you live in my area it will help. In my last post, I stated we were going out to purchase a welder. That was before I realized how much it cost:eek:

domino11

Tue 09 June 2009, 07:31

Donna,
What capacitors are you having a hard time finding. Let me know and I can suggest where and what to buy at good pricing. :)

docarter

Tue 09 June 2009, 13:34

domino11,
It's too late now, I've already purchased and received what I outlined in my last posting.

I was able to saved alot of money on the steel, so this shouldn't affect my budget.

docarter

Mon 15 June 2009, 07:38

Hello Guys,
Here are some pictures of my ongoing steel construction. I mentioned earlier, I work for in the utility industry. I went to several of our monthly recovery investment recovery sale and purchased the following:

Substation Bus Bracket
Several Control Panels

From this I was able to get a lot of steel, copper and aluminum very cheap. It took us days to take it apart. I also got lots of stainless steel high quality washer, bolts, nuts, brackets and plates in superb condition. I had lots of channels 8 x 2 that weighed 200lbs each. I elected to cut these in half and use as my cross bearers. I am in the process of reducing my pictures so that I can show everyone.

docarter

Mon 15 June 2009, 08:50

Okay Guys, here are some pictures of us cutting the cross bearings. Sorry for the quality but had to reduce them to the limitation of the site. The alum post will be used to build a work bench.

Gerald is it possible to increase the picture size?

WFY

Mon 15 June 2009, 12:30

Hi Donna,
What type of work do you do for the utility? I am retired from Ontario Hydro and spent ten years as an operator in 3 different generating stations and 15 years as a Customer Service Representative in distribution. Had some good luck an got a retirement package after 25 Years in May 2000. Not trying to make you feel bad - I just got lucky!! I just finished painting my machine (5x10). Gee - now I probably am making you feel bad.
Best of luck!
Buzz

Gerald D

Mon 15 June 2009, 13:02

Donna, if I make the pic size allowance too big it overflows some screens. Here are some hints on reducing pic sizes and keeping the quality:

Attaching photos to posts on this forum (http://www.mechmate.com/forums/showthread.php?t=394)

docarter

Mon 15 June 2009, 14:45

Thanks Gerald, I have IrfanView just needed to reduce it more than 80.

Hey Buzz, you are a lucky guy. I work for Georgia Power in our System Operations Division. I support our SCADA and Power Grid Applications. I am one of many Transmission Engineers. Earlier this year we had a voluntary retirement program, but our group was excluded due to our specialty. I still have about 10 more years to go anyway.

Here is the room where my MM will live. The room size is 25'x15'x9.5' with an 5' door opening. I have two of these rolling cabinets that will set under my alum table mention. This MM is going to be very heavy.

docarter

Mon 13 July 2009, 17:37

Hello everyone, I am now making good process. I have three different projects going on all at the same time.

1. Steel Construction:
a. Material cut for final assembly.
b. Welder Purchased (waited for sale)
Cost $450.00 Lincoln 175HP - This purchase was driven by other needs.
1. Continuous voltage control
2. Wide current range (25-175A) handles 24ga up to 5/16"
3. Comes with a gas regulator suitable for Argon/CO2
4. Available stainless/aluminum kit

2. Kitchen Project:
a. Shop for parts via Internet and local looking for quality with price in mind.

3. Cheap Chinese Spindle:
a. I eventual wanted a spindle and could NOT past up the opportunity to purchase it at a reasonable price.
b. I know this is going to delay my completion by weeks.

I have several questions in all areas and will asked them in separate replies.

docarter

Tue 14 July 2009, 05:07

Gerald.

Table Question:

Is there any harm in aligning the 6 middle cross bearing beams and the table legs around the centerline of the table frame? The outside cross bearing will still reflect the table surface offset of 3.9. I am about to weld the legs onto the main beam and realized that I drill the cross bearings holes on the frame centerline instead of the table center.:mad:

docarter

Tue 14 July 2009, 05:58

Here is a picture of my table progress.

Gerald D

Tue 14 July 2009, 06:27

Donna, from a strength/stiffness viewpoint, it is only the distance between the cross beams that matters, and not how evenly they are spaced. We are trying to keep the maximum space at under 16" [400mm]. You are going to have one wide space, 5 standard spaces and then one narrow space. The wide space is at the end that is going to see the most work, is it possible to lay an extra beam in that space? If your wood table surface is fairly thick, you could perhaps go wider on the beam spacings, but the wood wears away with time.

What size (and thickness) is that angle material that you have for the cross beams? It may be more more flexible than the channels on the drawing, in which case it will not be good to go wide on that one space.

The legs can go nearly anywhere.

docarter

Tue 14 July 2009, 11:28

Thanks Gerald for your quick response. As talked about in one of my earlier posting, I cut my cross bearings from C8x11.5. I attached a closeup picture. The side bolted to the main beam is 3" and standard side is 2". These cross bearings are heavy than what is in the drawing. They are also bolt with 1/2 recycled bolts. I don't think the table surface will experience any extra load, but you are the professional. What do you think?

Gerald D

Tue 14 July 2009, 13:11

Donna, you are going to be surprised at the strength comparison . . .

From http://www.engineersedge.com/standard_material/Steel_channel_properties.htm:

For the C8x11.5:
Ixx = 32.6 in4
Iyy = 1.32 in4

For the C3x5:
Ixx = 1.85 in4
Iyy = 0.247 in4

These are the (stiffness) numbers which are proportional to the resistance to flex in the beams for a given load condition. It can be seen that when the channels stand up straight, they are much stiffer than lying down flat.

The 3" channel standing up straight is stiffer than a 8" channel lying flat (1.85 versus 1.32). But you cut the 8" channel in half, so it's number becomes 0.5x1.32 = 0.66.

Even though your half 8" channels are heavier than the 3" channel. their shape only gives them 0.66/1.85 = 36% of the stiffness. Sorry that I only calculated this out for you now.

docarter

Tue 14 July 2009, 13:58

Gerald, this is not a problem. If the table appears to be unstable, I will replace them with more recycled channels. I have the resources. Currently the spacing is 13.75".

What about my question of the offset?

docarter

Tue 14 July 2009, 15:07

Okay Gerald, after reading my question and your reply, it appears that you think I only 6 cross beams. I have 8 cross beams with a spacing less than 16". The two beams on each end will be adjusted to miss the legs.

To give it more strength, I will add 4 umbilical plate to help tie them all together. Placing them symmetrically around the centerline of the table frame.

As stated before, if this appears to be unstable, I will replace them with recycled C3x7.

Gerald D

Tue 14 July 2009, 23:39

I meant that the following addressed the offset issue:

Donna, from a strength/stiffness viewpoint, it is only the distance between the cross beams that matters, and not how evenly they are spaced. We are trying to keep the maximum space at under 16" [400mm]. You are going to have one wide space, 5 standard spaces and then one narrow space. The wide space is at the end that is going to see the most work, is it possible to lay an extra beam in that space? If your wood table surface is fairly thick, you could perhaps go wider on the beam spacings, but the wood wears away with time.

From "You are going to have one wide space, 5 standard spaces and then one narrow space" it can be seen that I realised you would have 7 spaces which means 8 beams. Knowing now that your spacing is 13.75", and with the offset of 3.9", it follows that your 7 spaces will be:
17.65"
13.75"
13.75"
13.75"
13.75"
13.75"
9.85"
(PS - this gives a total table top length of 98.6". Is that what you want? See 10 10 123 D)

and thus: "The wide space is at the end that is going to see the most work, is it possible to lay an extra beam in that space?" meaning that you could divide the 17.65" with a 9th beam.

But then I saw in the photo that you were using relatively light angle and not channel. (I must admit that I don't read everyone's posts in detail to analyse deviations from the plans).

The ShopBotters were working with angle iron beams before and their early tables were just not stiff/stable enough for many applications requiring precise z-depth control. If you are going to be boatbuilding and cutting out plywood sheets, your table as it is now will be fine. The signmakers who tried cutting a flat background between raised letters suffered with the flexible tables - they had ridges that needed sanding between the letters.

Adding umbilical plates will do nothing for table stiffness.

Gerald D

Wed 15 July 2009, 00:00

I added the following note in post #2 of 1010302S Cross Support Beams under table top (http://www.mechmate.com/forums/showthread.php?t=270) :

Here are the minimum L-sections that will be about as stiff as the C-section in the drawings:
80x10 [ L3x3x3/8 ]
90x6 [ L3.5x3.5x1/4 ]

docarter

Thu 24 December 2009, 12:52

Hello guys,

I know it has been sometime since my last posting but I am still here. Work and family has distracted my physical work but not my research on building MM. Soon I will post my water cooling system for the 2.2kw Chinese spindle. I'm still waiting on parts and plan to build my own controller.

I wish everyone on this site a merry Christmas and a happy new year.

domino11

Thu 24 December 2009, 14:16

Merry Christmas Donna! Good to see you are still around. You are still in the running for first female to build a MM! :)

docarter

Fri 29 January 2010, 11:33

Hey everyone, Gary got our motors turning. He will post pictures today.

Gerald D

Fri 29 January 2010, 11:43

Well done Gary!!

I must admit that I was worried when he battled with the contactor :o. But I love it when folk prove me wrong! :D

garycdba

Mon 05 September 2011, 15:40

We have made some progress just sending pictures to document the build.
Will send more in the near future. The Kitchen project went well and we have finished all the welding and most of the painting we are currently wiring the machine to the control box.

12302

12303

12304

12305

12306

garycdba

Mon 05 September 2011, 15:59

Painting went well and we have started and finished the rails.

garycdba

Mon 05 September 2011, 16:22

Here are some more pictures of the rails. The rails went pretty good but i did have to buy an extra 10 foot section because i had problems lining up the skate.
Not our finest moment but we did okay. Once we figured out that we needed to cut the rails then placing them back to back we then grinded them level.
The last pic was the making of the stops

garycdba

Mon 05 September 2011, 17:49

Here are some pics of the Z slides and spider assembly.

MetalHead

Mon 05 September 2011, 19:10

Lookin good !!!

docarter

Mon 19 September 2011, 09:51

Still making progress here is a picture of the water cooler, 12v pump and enclosure with glass reservoir pump is very quiet.

docarter

Fri 30 September 2011, 06:37

Here are some pics of our progress will try to post some pics later
the motor connectors with 3 black wires and one yellow were really fun. keeping up with your pin-outs and troubleshooting a bad connection can be pretty time consuming. It is still good to be finally connecting the machine to the control box.

docarter

Fri 30 September 2011, 06:47

Some more wiring pictures that first gantry 3 button box get full quickly a oversize 3 button box is a must.

docarter

Fri 30 September 2011, 08:02

Had to change that small 3 button box keep those labels coming.
What a relief to finish the wiring everything seems to be working fine.
The VFD is connected and working time to start cutting.
Spindle temperature 115 degree f after running for three hours still need to address that issue.
setting-up and configuring mach3 will take some time, back to the drawing board lots of reading still to do.

TechGladiator

Fri 30 September 2011, 14:24

Donna;

Very Nice!... I am trying to catch up with you :).. Hopefully this weekend I will get closer.

Miguel

garycdba

Mon 03 October 2011, 18:39

Hi: Miguel hope you had plenty of success this last weekend.
I must tell you that once you get the machine to work the real problem is getting the machine to follow instruction with g-code we had problems generating g-code because we thought generating g-code would be easy. Donna is very good in Autocad and we just assumed generating g-code would be easy. Finding the right application to generate g-code is not hard there were plenty of free application that generated g-code but you must still do your research on how to use each application for your needs. We ended up using g-simple to generate g-code just to get us cutting we may have to use something else for production. I will give some screen shots on how to use g-simple found at g-siimple.com. Today the pictures will show the results of the our machine cutting we still have issues when we hit the ref all button our Z hits the stops and we don't know how to stop it from doing that. But we can get the machine to cut words hopefully this is enough to get a serial number. Here is the link
http://www.youtube.com/watch?v=EZSyNHxgufs