drill bits
 

Does anyone know a source for drill bits that have a 1/4" shank that will fit in a router? Need to drill 3/32" and/or 1/8" holes in thin aluminum (.032 or less...real thin)

Is a Hitachi M12VC router that I would love to use on the Mechmate under construction...is here already, has been soooooo simple, but need to drill small holes and collets are only available in 1/4 and 1/2. Sooooo I have to find some way to mount a drill bit or I'm gonna be stuck going to a spindle.

Anyone know what the taper is on the Makita routers? Maybe there is a collet that can be had to clamp a 3/32 bit... Understand they have been popular in DIY CNC circles for awhile...so figure I'm not the first person to try to cross this bridge.

Appears there are collets available from precise bits

Thank you sir!

DB, here is a video to get you thinking about the rubber pad forming. One possible source for the rubber is the big 3/4" sheets of rubber that gyms use (is also used for flooring in horse stalls when they are on concrete)...I bought a sheet to experiment with at Tractor Supply, was 3'x6' I think.

You can cut it and stack it to whatever thickness you need to press into. The Mechmate can make quick work of the aluminum blanks and the form blocks.

Already seen that one! I track the RSS feed for the EAA videos. Lot of good stuff there.
I will take a look a Tractor Supply though. I would have never thought of horse stall flooring, but it it seems like would have the right properties.
Have you done actual press tests? How well did it work for you?

I pressed a piece in a shop press and it compressed around the edges, which I believe is the important thing to roll the flanges around. Don't know what durometer the stall flooring actually is, but it is pretty firm. Brian Carpenter, the guy in the video said they had actually used tire rubber successfully (the sections of tread tractor trailer tires sling off on to road sides)

I designed a press with a 50 ton capacity but am waiting on some of the parts to get it going...the layout has changed a little, but I'll attach a model view of it.

Does anyone know what the Mechmate gantry actually weighs?...Y-car and all? Just curious how the rolling weight would compare to the plywood machine I have now...it is surprisingly heavy since it has several layers of 3/4 ply to make the front and all the pieces to form the legs and box it off...bet it is close to 50 pounds.

I-Beam main beams
 

Am looking for a picture/info on guys that have used an I-beam as the main beam on a Mechmate. Specifically what I want to know is if the X-rail was overhung past the edge of the I-beam flange like it is on the as-designed channel main beams. The rack mounts under the overhung X-rail...and if the X-rail isn't overhung on the I-beam then the rack has to be mounted under the flange of the I-beam main beam. This means (in my case) that the rack will be 5/16" lower than normal. Now the motor mount plates swing up under the racks, so there is some wiggle room, but would the racks being down an extra 5/16" cause a problem? The only I-beam build I have found is "buibui"s but it appears he hasn't posted on the forum in a couple of years...his X-rails are mounted flush so the racks are under the beam flange. Wonder if he had to modify the motor plates?
Not trying to just change things for the fun of it...have several reasons for going I-beam. And this will actually be, in American steel industry terms, a "W" profile, but most people refer to it as an "I" beam..."W" shapes have flat top and bottom flanges (excellent for bolting to without having to deal with tapered washers...and I got one 40' long for a song)

1planeguy

I have used I-beams and followed the build of BuiBui very closely. To have the rack mount directly under the X-rail, we have removed a portion of the I-beam to accommodate the length/width of the rack.

Cutting out a portion of the I-beam is similar to cutting down the x-rails. Attach a straight edge and follow it with a cutting disk.

Clayton

The cutting a flange back sounds like a extra pile of work...is there a compelling reason not to let the X-rail overhang like on a channel beam build? I did find a build thread that showed the X-rail overhanging...
http://www.mechmate.com/forums/showthread.php?t=3565
I have access to one of those metal cutting circular saws that supposedly would make cutting the flange back pretty easy

The beauty of building an MM is that anything is possible. The only downside to doing what you propose is a little more deadspace that would equal the I beam flange width. Just take that into account when planning your Y width and you'll be good to go.

Cheers

IMO it looks better when the x-rails are flush with the outside of the beam. Also, there is no overhanging metal to hook your shirt into as you walk around!!!

Clayton

Aesthetics are one thing...steel yield is another.
One of the reason's for the "under length" C channel is due to steel availability length.
Gerald had plenty of forethought in getting one machines main beams out of 1 standard length of 8" channel. If the beams were longer to completely support the angle, or not cut at an angle - it would require you to purchase more steel. The overhanging rail section is within the structural needs of the machine - thus a sound choice.

The "little overhanging" for those on the budget conscious machine, save about 250.00-400.00 for not having to purchase more steel for the sides.

...my little 2 cents worth today!

I agree completely.

If you choose to use channel, you accept the overhang as you should not cut into the channel to eliminate the overhang. It would compromise the channel.

If you elect to go with the I-beam, it would be OK to remove a a small amount of steel from the outer edge.

Clayton

I used I beams as well. I orginally intended to put the rack under the (supposedly :()parallel flange of the I beam.... for aesthetics plus it saved me some width ( very limited room around the BIG machine ).

After finding out the flange was tapered instead of parallel :eek: I also partly cut the flanges back ( it's only a portion not the entire flange width), since my gantry was already cut and welded. But in hindsight I would recommend to cut it back anyway ... or let it overhang like the original with the C beam, mounting the rack on the rail is more accurate.

Either option is fine, as long as your mathematics add up. As stated my motivation for less width and aesthetics led me to the first option. Do mind you have to be comfotable that every deviation from Gerald's plans (obviously) requires more input/planning ( equals work ) from the builder.

Your choice...:D

If your top flanges weren't parallel then your "I" beam was what in the industry is referred to as a "S" shape..."I" beams with parallel flanges are known as "W" shapes...clear as mud right :-)
I've been in structural steel design for 20+ years...doesn't mean I know how to make a Mechmate out of it, but I do know steel :-)

The extra inch or so of width by overhanging the x-rails isn't a deal breaker, so I'm gonna go that route...gotta figure up the extra width to keep my cut width what I need...

Hotrolled 200 mm I-beam still is only so-so in terms of dead-on dimensions ( it can vary in mm not in tenths of a mm - look up the norms), so even if you get your hands on the W beam I would still recommend; cut out the flange or extended like the orginal plans so you can mount the rack on the rail, like Gerald intended.

Think about it, if you are shimming the rails because your beam is uneven, then your rack will not be parallel with the rail when it's mounted under the I beam flange. It's not a lucky coincedence, Gerald has designed it the way he has, he thinks about that stuff ;)

It's all relative of course ( the pinion is spring loaded and allows for a wobble + the tape cushions ).

if one is bothered by the less then 1" (25mm) overhang of the rail, surely one would be impossible to accept the motors overhanging.
I'm not bothered by both or any overhang of any sort in the original MM design.

Agree with both the above posts...gonna overhang the angle and mount the rack under the angle instead of the flange. Fox is correct on the hot-rolled steel tolerances. The AISC (American institute of steel construction) allows rolling mills +1/8 -0 in flange width on a W-section...tolerance might vary in other parts of the world.

One is also bothered by the motors, so much in fact one came up with a cunning plan to have the motors pointing inwards from his gearboxes, so the motors are running under the flange ( handy thing that I beam :D)

Structure modeled, ready to get to building
 

Got the machine structure modeled and data to the steel shop. Everything you see will come to me as a ready to weld/bolt package. All plates with holes, beam flanges with holes, everything cut to exact length.

According to the 3d steel modeling program I use, that is 2209 lbs of steel right there...Believe this will be a "solid" table...

Picture here....

Cutting area will be 12'-6 x 4'-6...to get the length I needed I am basically running this thing within a couple feet of the building walls on 3 sides...will have just enough room to slip around it to sweep and check on the machine. Because of that problem, I have arranged the bracing to allow 4'x8' sheets to slip between the legs on the near side to a storage rack on the bottom. All loading will be over the rail :( unless a roll up door is raised and then can come from the end...don't like that, but that is the option I have...(you know the saying, when you have lemons, you make lemonade...)

Ready to get going!!! Should have a laser kit coming from Metalhead in the next few days and this steel package will be 2 weeks out...soooooo time to figure out the electrics and get a kitchen table project going.

Rock-n-Roll! Will you remove materials over the rail too? You may have to come up with something to slip over the rail for protection.

I thought about that...my rails are gonna be ground rails...was thinking the rails are definitely not gonna get hurt by plywood/MDF but the ply/MDF could get gouged some. wonder if I could find something like those plastic U-channel things that ice skaters put on their blades when they come off the ice?

I was thinking something like that too. The other issue would be rail alignment. I'd think you need to keep from smacking it around, so what ever it is really has to guard against that as well.

As long as you are not throwing the wood, it will not be hurt. I have to side load my machine only as I have a wall that is inconveniently in the way of the loading section of the Mechmate. The hardened V-rails I actually use to help slide the wood onto the spoilboard. I have never seen any damage to the wood as of yet.

Good to know...and high five to another "space challenged" Mechmater ;-)

...I made some rail caps by ripping a dado in the center of a 2x4 for each rail to keep everything safe when loading over the rail or just parking the machine at night.

People in my shop had a tendency to use the rails as a place to drop hard heavy things from the forklift when driving around. The 2x made a nice cover.

Nice idea...like it.

If you are referring to the spoilboard distance from the floor, I would recommend a little lower than your hip joint height (two inches below). This allows for easier reach from the open ends of the bedway. The reason I say this is because if you are 6'6" a bed that is 26" from the floor if working at it all day is a back pain but a bed that is 36" and you are 4'8" will cause discomfort also. You best comfort zone is around your naval for standing work on a workbench but the machine is not a workbench however you seem to want be able to use it as one also. So you need to form the build based on your needs.

Know what you mean...no such thing as one size fits all. Good info.

Spindle vs. router
 

Okay, looking for the pros and cons. Is a stupid long story...but end of it is this, I already have a 2.2 KW chinese spindle with the matching HuanYang (sp) VFD sitting in a box waiting to be installed on something. I use a Hitachi M12VC on the little plywood CNC I have now...it has been bulletproof and about as complicated as an anvil. It isn't horribly loud, but supposedly the spindle is quieter. In this Mechmate I am going to setup the router/spindle to be controlled by MACH 3 (it isn't on the current machine). In trying to get my head around all the electrics, I completely see how this works for the router but the whole spindle with chinese instructions has me banging my forehead on the table. Am considering just getting rid of the thing and sticking with a router.

Give me an opinion...

If you have one of these spindles and know of a decent tutorial on setting it up wiring-wise I would be much appreciative of a pointer. Have spent some time on CNCZone, which is like trying to read the original chinese instructions...aggravating at best.

I guess I really want to know if there is enough "benefit" from the spindle to justify the learning curve to set the thing up...I seem to see plenty of MechMates with a simple store-bought router...