Félicitation Melissa! I think I can see your landing strip from here ...did I heard poutine?
yumyum

Great thread !! Congrats on number 83 !!! Who's next :)

Great Job. Completing and getting your serial number is a wonderful feeling of success.

Congratulations on #83 and completing your machine.

Cool, you got a prime number. (Wasn't your undergrad student ID number also prime?)

Thanks for all the congratulations! I'm happy to have a working machine, although it is a large conceptual leap from "normal" machines to CNC. It's a completely different workflow, and sometimes a bit alarming, like when the gantry is doing a rapid towards x=0 and stops just shy of the hard stops. Whew.

I've already derailed the gantry once... configured X to run in reverse (so the numbers ran the correct way), forgot to do the same to the slaved A axis, slow jog with the ShuttlePro, and 30mm later, the diagonally opposite wheels were off the rails with a loud THUNK. Oops :o.

A quick dimension test confirmed my motor setup: I cut a 100x200mm rectangle and a 100mm diameter circle, both measured correctly.

On to dust collection, before I completely cover the workshop in sawdust!

Updated Builder's Log
 

Melissa,

May I add my congratulations on completing your MechMate and earning Serial #83.

Here is the Updated Builder's Log.

Please review your entry and let me know any changes you want to make.

Great job!:)

Congratulations miechle. Nice looking machine :)

It really feels nice with a number beside your name. I'm still trying to get used to it :D

Melissa with the size you have i suggest you try with a wireless keyboard. I had one and it's really making a huge different to gain fine control when locating your work piece 0,0,0. It works for a 10m range or more.

Machine upgrades
 

Having built my MechMate, I was much less intimidated than otherwise, to rewire parts of the gantry.

I ordered a larger junction box for the gantry, which made the wiring much simpler. Having a pushbutton box and a junction box made for a very full junction box, and many more wires.

I also wired in the proxies at the same time. No photos of that part yet.

Attachment 12136
Attachment 12137

Attachment 12138

Dust Shoe
 

Next up was making a dust shoe. I purchased some "8020" aluminum profile to bolt the assembly to the y-car. My dust shoe is manually positioned, so it doesn't lift with the router. I may revise that later, but this works fine for now.

The brush is taken from a shop-vac nozzle from the hardware store. Bending it into the new shape was not pretty, but it works :rolleyes:.

Attachment 12139

The piping is standard 4" PVC pipe. I found a "sewer adapter" which happens to fit dust-collection hose perfectly :). I still need to take some photos of the hose support on the ceiling -- which uses a slide to accommodate the length of the table :D.

With the dust collection now functional, I could set about surfacing the table. I was astounded at the amount of dust collected. 1.5mm from the table filled the dust collector bag more than halfway :eek:.

Attachment 12140
Attachment 12141

MDF clamps
 

There have been some DXF's of MDF clamps posted on the site -- this is one of them. I manually nested the parts (fairly easy when they're the same shape).

The middle section is pocketed, to allow for a bolt to pass through, with a knob above the table. My plan is to drill 1/4" holes through the spoilboard in a regular pattern, and then use 1/4" threaded rod with knobs above and below for clamping.

Attachment 12142
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Attachment 12144

The clamps are cut in two sections, and then glued together:

Attachment 12145

My solution for inexpensive knobs: cut them from MDF, and insert "T-nuts", which cost about 10c each. Sure beats $1+ for the fancy ones! :D

Attachment 12146

Dust Collection: Thien Baffle
 

I thought that the dust quantity would be a problem, and surfacing the table confirmed it for me :eek:. Next up: building a Thien Baffle to separate the dust ahead of the dust collector.

I built a smaller version for my shop vac, which works astoundingly well. It was much easier to build this one, not needing to cut the circles with a jigsaw anymore :).
Attachment 12147

I made the lid from two layers of 1/2" plywood, glued together with PL Premium adhesive. This is a polyurethane construction adhesive, which expands to fill gaps, and is very strong. The workpiece does need to be well clamped while curing, though:
Attachment 12148
Attachment 12149

Hose parts are for 4" PVC sewer plumbing. Ideally, the elbow should be flush with the plywood. I'll see how this does, and may opt to add a "false lid" later, if it doesn't work as effectively as it should.
Attachment 12150

Hey those look just like mine clamps :) and the knobs too

I have to check my shop for missing ones !

good work, and they will serve you well, just a note, when doing something slippy like plastic or acrylic wrap the tip of the clamp with thin rubber, it helps.

Hi Melissa,

Really nice build. Post some more photos of the clamps in use when you have completed them. When you glued the second spoil board down over the first, how did you clamp it to get even pressure across the boards? I'm thinking of routing dadoos down my spoil board and install "T" track for the clamp hold downs. I saw in an earlier post you installed your computer into the control box. How is this workin out and do you have to open the door to turn the computer on?

Gary

Thanks for jogging my memory... I had an "oops" while cutting parts for the dust shoe.

I was cutting 2mm Lexan for the top surface of the dust shoe. Two holes (40mm and 107mm), and then the outer profile. I figured there wouldn't be THAT much force on it, so I taped around the edges with high-tack masking tape.

About halfway around the outer profile, the workpiece lifted off the table. I hit the yellow feedhold button on the car, which stopped the motion, but not the router :eek:. Next was the e-stop, now that the part was ruined anyways.

I will say it took a huge amount of self-discipline to NOT reach in and try to "save" the part. Lexan is cheap, compared to surgery and physiotherapy!

I'm making it a habit to not even lean on the MechMate, even when it's turned off. Much better to always treat the machine with respect, so that when things go wrong, the automatic reaction is to step back. With the proxies and the hard stops, there's little the machine could do to damage itself now. So all I need to do is make sure it doesn't damage me. :D

Hi Gary,

I drilled holes and used "particleboard screws" to clamp the second layer in place, as well as C-clamps around the edges. The screws have a very coarse wood thread, and a pan head. Once the glue was dry, I just removed them.

For the T-track, you need to consider what depth to install it at, and whether you're willing to cut into your spoilboard. You certainly don't want to hit the track. This is why I'm going with through-bolts.

The computer in the control box is working out great. I have its power supply switched from the big rotary ("Ensto") switch, so the computer stays on if I trigger an E-stop. For on/off and reset, I installed two momentary key switches on the control box. These trigger the contacts on the motherboard, the same way the little pushbuttons on a "normal" computer case do. I used key switches on purpose, so I can't accidentally turn off the computer by bumping a switch on the control box.

Melissa

Thanks Melissa,

I have a spare computer and now I think I'll disassemble and see if I can wire a momentary switch to it and if so I will strip it down. Did you mount a disc drive in the box or just did away with it? Do they make a USB adapter which can be mounted throught the contro box? Would like to transfer cutting files this way.

On my other cnc router I use "T" track and placed a scrap piece of luan under anything I cut completely through. This way I don't cut into my table. On your set up are you planning to pre drill equally spaced holes or just drill as needed for your through bolts?

I ordered my rack and pinions and also the tool steel plate for the Z slide today, so I should be getting close to all my mechanical build. The electrics will be a new challenge. I can't decide if I will install limit switches at this time of the build or wait. I have been reading up on this and have a question. If I have limits swithes at home position, is there an override to enable the gantry to bump the hard stops to square the gantry when first starting up the MM.

Gary

I used a 2.5" laptop hard drive for the computer, also mounted in the control box. Rather than build a mounting bracket for the drive, I just used 11-gauge solid wire, twisted around the motherboard and hard-drive screws. Good enough for a 50-gram drive :D.

For the clamp holes, I've drilled on approx. 200mm centers. We'll see how that goes. I made a DXF with intermediate holes as well, so I can add those later if needed.

I ran my machine without limit switches at first. It was easier to get the electronics wired and behaving without them, I found. Adding them was fairly simple, having completed the control box already (which was way more complicated). I opted for the relay solution (instead of the circuit board, posted elsewhere around here). Four relays mounted in a junction box on the y-car. Two of the proxies are already on the y-car. The other two are on the gantry, and just need a short extension to reach the y-car.

I haven't figured out the bit about squaring the gantry yet. I do know the proxies trigger before my gantry hits the stops. Hopefully someone else will chime in on how to do that :).

Hope this helps,

Melissa

Forgot to mention: I used a Neutrik USB panel-mount connector. This way, I just have a short USB cable from the motherboard to the connector. Outside the box, I can plug in a thumb drive to load the GCODE.

The MechMate computer is not connected to the network at all. This means I can do away with all kinds of things in the operating system, most notably antivirus software.

My total "boot time" from power-on until mach3 is ready to cut, is about 90 seconds.

Thanks Melissa, I'll have to find me a USB panel mount. I'll go ahead without the limit switches at first like you did. I have never had any on my other router but would like to install them on the MM. Lets hope some one chimes in on squaring the granty. My pinions arrived today and I'm hoping the track will arrive by Friday, that way I can install and true my rails. How are you liking your steppers with the gearboxes?

Post some pics when you use the new clamps.

Gary

Here are some threads for adjusting the beast...

Setting the Y-axis square to the X-axis
http://www.mechmate.com/forums/showthread.php?t=231

Setting the Z-slide square (perpendicular) to the table top
http://www.mechmate.com/forums/showthread.php?t=2553

Seating the Y Gantry on the X Rails - correcting a twisted gantry
http://www.mechmate.com/forums/showthread.php?t=663

Enjoy ;)

In thread t=231, Melissa, I hope you have ideas on how to make "a" thin sheet of MDF that's the full length of THIS table, rigid enough to flip over intact.

t=2553 router's already trammeled.

Hi Steve,

Thanks for the links. What I was wondering about is if you have home/limit switches how do you overide them to bump the mechanical stops to true the grantry with the steppers. It would seem if you tripped a limit it would stop before bumping the mechanical stops. Maybe an overide button in Mach?

Gary

Gary,
If you read the first post in t 231, Gerald suggests that auto squaring the gantry on a MM is not possible or at least not probable. He suggests that after squaring the X/Y that the squareness of the gantry will stay that way unless you hit something or run the gantry off the rails. I have found this to be quite true. I have limit switches on my machine and I rarely hit the hard stops. If I need to square the gantry I would disengage or power down the motors, pull the grantry to the hardstops, which are set to make sure the gantry is square, and while holding the gantry to the stops, engage/power up the motors. This will lock the gantry square. I will run the gantry over to the limits, which trip, override the limits, and run the gantry pass them.

Thanks Steve,

That is what I was wanting to know. I remember reading that the motors held the gantry square once turned on, but just didn't know how everyone was squaring their gantry when first turning the machine on. I knew by rolling my grantry by hand that this was causing some out of square and that the machine would have to be checked when first turning on.

Thanks again, Gary

Thien Baffle, completed
 

Some more photos of the Thien dust separator:

Attachment 12231
Attachment 12232

With it connected, I had to do something with all the sawdust from surfacing the table. I felt like a vacuum-cleaner salesman, as I proceeded to empty the bag onto the floor, and then vacuum it up: :D

Attachment 12234
Attachment 12233

The result is that the vast majority stayed in the Thien separator -- I couldn't tell if any made it through to the dust collector's bag. Mission accomplished!

More clamp knobs. I used a two-part toolpath. The first part made the holes in the middle. I then inserted screws with washers, to hold down the knobs during stage 2.

The second toolpath cut the round base of the knobs, and then the handle part. With the knobs attached with screws, I didn't need to bother with tabs to keep them secured.

Attachment 12235

click-together boxes
 

My first attempt at click-together assembly. The box is made of 1/2" plywood. The fit was bang-on, and the tabs make assembly much easier, as it self-aligns. More about boxes below :).

Attachment 12236
Attachment 12237

Squaring the gantry
 

My brother Camille was visiting recently. He helped me align the gantry, among other things we built using the mechmate.

We found it challenging to square the gantry by incrementally adjusting the shims. In fact, at one point, we adjusted it square. However, the direction we adjusted in, brought one of the X motor bolts into contact with the rail, which we discovered when pushing the gantry by hand, and encountering resistance. We quickly reset the shims on that side of the gantry (nearest 0,0), and made all further adjustments on the far side.

The method we eventually employed was to place half the gantry on blocks, and measure the required offset directly. Note the circled areas, and the wheels sitting aside :eek:.

After making these adjustments, the results were verified by cutting two sheets of plywood, as per Gerald's squaring instructions.

Attachment 12238
Attachment 12239

Attachment 12240

broken clamp
 

The MDF clamps have been doing surprisingly well. In cutting about five sheets of plywood, we only damaged one clamp, and that was by hitting the tip sideways while unloading a sheet. In normal clamping use, they're great!

Attachment 12241

More Boxes
 

With the gantry squared, we now had two sheets of plywood, about 25mm narrower in both dimensions. Hmm... what to make... more workshop boxes, obviously!

A full sheet of plywood, clamped on the table. Two sets of boxes were made from $13/sheet "sheathing" plywood. One set was made from $23/sheet "G1S" sanded, which was totally worth the extra $10, just for the fact that it was FLAT!

Attachment 12242

Cutting box parts:

Attachment 12243

Attachment 12244

Attachment 12246

Releasing the parts, cutting the tabs with a jigsaw. This was easier and more predictable than a chisel.

Attachment 12245

The first batch of boxes. I'm astounded how well these came out, given they were built with the cheapest grade of plywood available.

Attachment 12247

Second batch, two different sizes. The taller ones are the same size as typical "banker's boxes".

Attachment 12248

Around this time, we had a visit from Rob and Hannie, two Dutch boaters from New York, who were moored at the canal near our house. Rob needed a step-stool for their sailboat, and my boxes were exactly the right size. So, my first sale of a MechMate-produced part :D.

Attachment 12249

Nice work Melissa. Any chance we could get some close up photos of your dust foot, pvc pipe and the mounting? I ask because I am just getting a dust foot under construction. Thanks.

I think we need an additional criteria for a serial number - show a pic of your first sale to a happy customer.

Good stuff there!

Melissa, did you use screws and glue to assemble the boxes?

Excellent display of a MM in use. Well done Melissa. You might want to start saving all those cut off scraps for the wood stove. Winter is coming soon!

Love to see a machine making things - anything in fact. Well done.

A hint for you on removing your parts from the sheet. At the Maker Faire I saw some CNC people cutting their parts free using a straight cut router with a ball bearing guide.
Make your tab only thick enough to hold the part, even something like 3-4mm is fine then run the bearing guide along the smooth edge to release the part.
It leaves a beautiful router finish where the tab once was.
A a benefit it is also very fast to do.

Regards
Ross

Hennie: polyurethane construction adhesive, clamped during cure by brads shot from a pneumatic gun.

Sean: we had quite a bonfire out back. The next morning, the coals under the ash were still hot enough to ignite plywood. (And what does a Floridian know about winter anyways? Oh, right, all the snowbirds who come down from Ontario tell you stories.)

Ross: did they do that on a spoilboard, or in free air like we did with the jigsaw?

For any inquiring minds, we used 4x8 ft plywood instead of table-sized MDF. 4x8 was big enough, and the remaining scrap was plywood rather than mdf and thus usable for other projects (as you see above, with those boxes).

I leave my tabs 1/2" long and 1/4" thick. The G code goes back and cuts them out last. Very little resitance when cutting them. Part doesn't move and very little sanding, if any