Upgrade proposal. magnetic clamps

ok. so lately Ive been cutting alot of thin materials. 1/8 plywood and 1.5mm-3mm g10 and all of them about 2 foot wide.
the problem is that all this thin material at 2 feet warps and bows every time i make cutouts. and i cant reapply clamps because there is a sacrificial piece as well and more than likely a moving machine. so Ive been using weights but there so big they often get in the way, and one time it even deformed my cut because it was to big to avoid. so i got to thinking.

what if i clamp a steel sheet followed by thin sacrificial wood. and then my g10. and just placed a small to medium sided neodymium magnet to weak points after my cut outs. of course crashing in to one could be pretty awful. but small relocateable claps when the machine is moving. brilliant.

i already checked. my 1 inch cubes can already clamp tightly enough through all the material. and maybe smaller ones can still clamp similarity

what do you guys think

I have been using double sided wood turnin tap on a thin piece of wood to attach thin stock to. Has been working like a dream.

The XFasten Indoor Carpet Tape works extremely well to hold down thin materials (or thick ones)

Sorry, but I really doubt it’d hold very well. You’d be better off making a sacrificial vacuum table top box.

I have been using carpet tape myself when milling 5mm acrylic and 3mm plywood, and i have had good results. Make sure your material and wasteboard is clean of dust. Just be very careful when removing the piece after milling, i have cracked a few 5mm boat dashboards and it sucks. And its even harder on very thin plywood, but it works well.

But ofc a vacuum table is the way to go if your making a lot of parts.

I wanted to build a vacuum table. But i dont know all the things i need and anymore loud gear in my house and dad will kill me before i make enough money to put it in a small shed.

Also. I think a few people here are underestimating the power of neodymium. The 1 inch cubes took me and dad both to separate. And they where seperated by a quarter of an inch. And my test was still pretty strong after being separated by wood and g10

Of course my goal is not to remove normal clamps to keep the material tame. But rather hold weak points down during the cutouts.

The tape sounds like a neat idea to, and ill research it

I think you should give it a go. I would pause the cuts when you place them down to hold the piece that decides to flex. I have had issues with even larger pieces that once they start to cut they will pop up just enough to throw the cut off.

actually. pausing isn’t a bad idea. but i should be able to place magnets so quickly that my only problem would be trying to remove them while running.

im cutting out some drone frames. and my plan is to use a 2x2foot sheet and cut them one at a time. and move to the next. in case of hardware failure like bit breakage. as im pretty keen on accuracy and i dont like to try realigning a second cut, since bit changing always throws off my machine. so i can literally just drop a magnet at places its already done with so the next area is stable.

speaking of which. the drone frames are in there final stages. so soon to be relieved.

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That should not be happening. I swap bits all the time, no problem.
Are your motors not staying on and locked? (there is a setting for that)
Or are they slipping when you tighten / looses the collet? (motor current pots may need adjusting)

Please carry on. Its an issue ive had for a while now. Its fairly locked in when its on but given the force needed to lock in the collet it normaly gives and slips a millimeter or 2. And the gantry has at least 4-5mm of wobble dispite having flurted with overtighting the wheels.
I also dont use my Homing function. I couldnt find the final setup instructions and they dont contact anything. So i do everything manually. And its rather frustrating because i could really use these abilities.

but its clear that using just a 1.4mm bit is only really good for the detailing and poor for cutouts. My 3mm or bigger would do much better.

By the way i use vcarve and gcode sender


Check this page, step 14 and look for the line:

Now is a good time to add the “actuators” for the limit switches.


thank you. i looked it up and added it to my build and will have it finished and tested soon

also. my test look good so far. it works and it holds well. so ive already ordered more magnets.

there are a few issues. its of course not perfectly flat. nothings ever that easy. but my dads a metal worker. and he said we just need a solid ground, a REALLY heavy hammer, and some loud noises. and it wil be flat as can be.
other than that. i just a 1/4inch thick plywood and then 1.5mm or 3mm and the clamping force is really good.
but its not cheap for what it is. and its pretty much a specialized solution for me.

there is more work to be done though. i want to rubberize my magnets. 1 inch cubes are not particularly safe. they have about a 110pounds pulling force. and there fragile. so can can shatter on impact with each other. and repeated use will break them eventually since im moving them alot.

i also need to make a storage case for them out of wood. because i cant just put them together. there incredibly difficult to separate . and i need a separation device to. which i know how to make.

it is just as strong as i expected to. material does not move at all. but it doesn’t leave standard clamps obsolete. it just stops the material from vibrating

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