Not sure how much you plan to cut into the waste board, but polycarbonate, while aesthetically pleasing, is an expensive material to use as a waste board. Also it is a lot denser than something like MDF so if you accidentally plunge a little too deep you bit/router will not be happy about that. If you are planning to mill mostly above the polycarbonate top, I think its a cool looking and probably a pretty dimensionally stable top.
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I don’t intentionally plan on cutting into it, but my “intentions” don’t always match reality.
This idea sprung into my head after investing 90 minutes of CNC time and another 30 minutes of my own time installing threaded inserts. But you guys are finding the flaws in my logic, which is what I wanted to know.
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Since I have gotten my HDZ, I have found no reason to cut into my wasteboard. I prefer to keep it clean and level and if I plan to cut through my material, I will clamp additional MDF/Plywood underneath. This was hard to do with height restrictions prior to owning a HDZ.
Big +1 to the expense factor. I don’t know what prices are like where you are but here, 10mm polycarbonate costs 146€/m² while 10mm MDF costs 10.63€/m². Given that, I definitely wouldn’t want to “waste” polycarbonate.
Plus, wood is way more environmentally friendly and easy to dispose of (though that too depends on where you are).
The polycarbonate was purchased from lowes for ~$32usd (30"x36"x.08") and I was able to make two tops from the material. So at ~$16usd each. More expensive than wood, but I thought it was a better overall value due to the time invested into making the threaded insert board.
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One thing I was considering wasteboard wise for a while was a puzzle arrangement centered on holes for threaded inserts where the pieces either had, or didn’t have a hole and could be swapped in at need — as pieces were cut into they would get sorted into bins based on how deeply they were gouged — when a bin was full all the pieces would get installed and surfaced.
Obviously didn’t bother, instead I’m back to PVC filler strips w/ spacers limited to the cutting area and which are held in place by a single fastener:
Now I just need to remember the next time I’m inserting the spacer strips to just shave off a bit of the angle rather than drill a new hole.
Voted for “bad idea”.
Ascetically, it looks fantastic. Love the look, but for a wasteboard? It’s a wasteboard because it’s designed to be replaced and surfaced. MDF is super cheap and surfaces quickly.
Besides the cost, you’re also limiting friction from the washboard. You’ll really have to make sure you have multiple contact points with your clamps. I’d nix both the bamboo and the polycarbonate pieces, because of cost, but again, I love the way it looks.
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How does the blue tape stick to the PC, maybe too well?
I would cringe every time I accidentally cut into it because it looks so nice, and surfacing it to remove the cuts won’t really work. I have a few more concerns though:
- Lack of friction. I don’t know what you cut or how you clamp, but you have no help from your wasteboard here. I often surface 8/4" pieces of hardwood without any clamps or tape at all. I shim the wobble with some old sandpaper discs and let gravity keep it in place while I remove small fractions of an inch to get a flat surface.
- Static build up. I’ve used my CNC to level large epoxy inlays and that used to be the only thing that caused a static pause. I say “used” because I fixed that by powering my router from a different breaker and that seemed to fix the problem.
- Cost. Not that it’s too expensive to be a wasteboard, but I wanted to make sure you know that PC can be free. You might struggle to find the exact piece or color you’re looking for, but if you keep down this path, contact your local sign shop for scraps before you head over to Lowes. My local Fast Signs franchise gives me all the scrap PC I want.
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Great points, I think the conclusion we are all coming to is that this was a bad idea. Not necessarily the decision to put something between the what I will call my threaded insert board and the work piece. The “bad idea” was choosing polycarbonate, which was obviously just for vanity reasons as the bamboo threaded insert board just makes me happy to look at.
If I get a disconnect (static) then this experiment is over. If I have a work part move because it slipped on the polycarbonate then this experiment is over. If neither of those happen then the two polycarbonate tops will last however long they last, then I will move on to whatever my next bad decision is.
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Everything’s a learning experience here. It’s definitely very cool looking!
Once you run out of PC, my vote for your next sacrificial bamboo saver is a large sheet of anodized aluminum. lol
I have not tried the blue-tape yet. In my time with the Nomad it was clamps and/or double-sided tape. Just got the Shapeoko setup and will eventually try the blue-tape method.
I will say that regarding two sided tape, it will stick to the polycarbonate much better than to MDF, and a little better than the bamboo. But that tape is a different creature so the results with the blue-tape could be different
On the static front…
Whist observing my awesome success in not grounding my dust boot and how many kg of plastic chips it could hold at one time on the PVC skirt I remembered this stuff that I used at a previous workplace to leave a semi-permanent semiconductive antistatic coating on things. Might be worth a try.
It’s like a museum display, “ColdCoffee’s first Shapeoko wasteboard.”
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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.
Very tidy design. Well done.
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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.
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Yep, that’s pretty much right as I understand it.
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.
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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.
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Aside from interfering with the aesthetics, would double sided tape underneath the polycarbonate mitigate that?