First, let me say it looks great, for now. Hard materials are brittle and tend to scratch easy. If you stay the course, static is as simple to overcome as a length of wire. Simply secure it via one of your corner bolts to the surface on one end, and then to the ground wire of the machine. This will balance the static load and send it to ground, not allowing it to build up.
Other than the fact that before long, the look you have achieved is going to be marred with scratches and chips, there is one thing that really concerns me with this.
The waste board is intentionally made out of a soft material. It absorbs any abuse that may occur. PCs claim to fame is it’s impact resistance. By replacing it with such a hard material, more of that abuse will translate back into the tool. With the right bit and settings, the machine could chew through it all day, I’m sure. But if your pushing your limits on a piece of soft would and accidentally plunge into this combo, what would the outcome be?
Personally, I would take that and use it as a display of some sort. maybe a back drop or stand for pics of your projects. It looks too good to be sacrificial.
Anything is worth trying, & you put some effort into it, so for that, I’m glad to see you didn’t get bogged down in hand-wringing & just went ahead and did it. I don’t know what a practical use for it would be, but we live isn’t a universe faith nearly infinite possibilities, so there may come a project in your life that it fits just perfectly, and then you’ll have the solution. All ideas are good ideas potentially, some just await the right conditions.
I’m not sure about that, but maybe someone more knowledgeable than me can set it straight. My understanding is that static in non conductive materials can be complicated and difficult to deal with. Because the polycarbonate is non-conductive, static build up across the surface cannot “conduct” away as it would in a conductive or semi-conductive surface.
If you attach a wire to one part of it then only the static build up near (touching) that wire will drain away. That’s why special conductive hoses are impregnated with Carbon I believe or something similar so the material becomes semi-conductive enough to drain away any static. I think though, that the static might be more of an issue with stuff sticking to it making it quite an annoying waste board as pretty as it is.
Polycarbonate is used as an electrical insulator, it used to be used as the separating film in capacitors to stop charge leaking between the plates.
If you place a conductor at one point on the polycarbonate you’ll locally attract some of the static charge, but more through the air above or humidity deposited on the surface than through the polycarbonate which is a much better insulator than air. (This is one of the few good things about living in the UK, it’s always damp so we don’t get much static).
If, on the other hand, you apply one of the spray on anti-static coatings which provide a certain amount of conductivity over the whole area you’d be able to conduct away any accumulating static charge from the surface. A strip of aluminium tape along an edge makes a good way to ground out that sort of coating. This would still allow charge to build up on the other side of the polycarbonate so make sure you spray the side you want grounded, or both sides, otherwise you just made a capacitor with a very small number of picoFarads capacity.
Thought I would give an update after spending an entire weekend enjoying the new Shapeoko.
Of course have already accidently cut into the polycarbonate and it was 100% user error (or the technical term in the programming world, an ID-10T error)
The BIGGEST problem I have seen, and this alone is enough reason for no one else to try this… I was using some two sided tape to hold some wood to the polycarbonate. The polycarbonate is flexible, I was using an upcut bit and there was enough force to lift the part AND the polycarbonate. Even though the polycarbonate was attached to the threaded insert table, it still lifted enough to effect the cut.
So lesson learned, this was a BAD idea.
On the plus side, no static issues with the polycarbonate.
You would need to have the tape spread out, or surrounding your work area. In the picture below the work space is empty, but I have clamps along the top, left and right edge. This past weekend I was running in a setup similar to this, with a board in the upper left corner. The board was roughly 10x5, and when cutting along the bottom Y axis I saw the board lift… at first I thought the tape (between the board and the polycarbonate) had failed and then I realized it wasn’t the tape, the polycarbonate was bending.
So either a lot of two sided tape, even or more clamps.
The lifting forces with an upward helix cutter can get quite large, I saw my XXL baseboard deflecting during heavy cuts on birch ply before I bolted the thing down.
A workholding base you can’t trust to stay where it’s supposed to be is a problem you should avoid whenever you can.
and it was 100% user error (or the technical term in the programming world, an ID-10T error)