I have a fairly stock C-Beam I use to primarily cut .032" aluminum sheet. I use a coolant mist/spray to do it. I currently have the standard 3/4" MDF waste board attached on top of the X/Y plate. I have a second 3/4" MDF waste board on top of that with is drilled and taped for 10/32 screws for clamps that I hold smaller temporary custom for the job, waste boards made out of, you guessed it, 3/4" MDF. Doesn't take long for all this MDF to soak up the collect and expand and become unusable. I'm thinking of replacing the MDF with something that won't absorb the coolant. Of course it has to be easily cut, cheap and readily available. It is a waste board after all. In the cheap department it's hard to bet MDF so I expect it will cost more but in the long run, less expensive and time consuming as it won't need to be replaced as often or at all. Has anyone used a phenolic material or plastic such as HDPE or something like them? I'm thinking I could replace the bottom 2 layers of waste board on my machine setup and if cost is to prohibitive or perhaps cutting the material chosen a little more difficult, only use MDF or the actual tip custom project waste board. Looking for material suggestions? Thanks Bruce
Maybe apply 2 or 3 coats of polyurethane varnish (top bottom and sides), No good of course if you surface your spoilboard every 5 minutes!
As 98% of my cutting is .032" thick aluminum sheet, my bit goes through the material and into the spoil board every cut. So that idea wouldn't work. As stated when I build my C-Beam like everyone I put a 3/4" spoil board on top of the aluminum plate. That board I thought to hard to be changing all the time so I added a second 3/4" spoil board to that and drilled and tapped it for hold downs. As so much work went into the second board, most of my cuts are done on a third 3/4" spoil board clamped with the work to the second. I certainly could polyurethane the first spoil board as that really has become part of the machine as it has outriggers running on rails to stiffen the corners. Not so much the second spoil board as it is drilled and tapped in a 2" sq pattern and machine screw run in and out all the time. I have about 3 final spoil boards that have some fixturing holes and pins and of course the part pattern that I could reuse over and over. As the bit always hits these set up spoil boards a poly coat would be useless. This is why I thought about a phenolic or plastic material for the first and second boards which really aren't true spoil boards though they might get wasted over a years time. Thanks for the idea. Bruce
I don't know of anyone else trying it. And herein lies the key: Try it! The world needs more trailblazers
Rats. I'd hoped there was another (many) trailblazers like me who had tried it, but had perfected it, which I did not. You see a while ago I tried using a CutCo plastic cutting board for a spoil board. Mixed results as you can see in the photo. The problem might be two fold. One the CutCo board is of unknown plastic, but it is soft and melts rather that being cut. That leads to the next issue in that I'm sure the CutCo board could be cut at some speed and with some bit, but it is not the speed and bit needed to cut the actual material being purposely cut, in this case .032" thick 3003H14 sheet Aluminum.
HDPE is the way to go imo, super stable not crazy expensive. HDPE is very slick, will need to really clamp material, more than with mdf. quick google and I found this guy, this is not uncommon. https://www.youtube.com/shorts/d7K7PndGDDQ Cheers Gary
Oh yes, the poly used in that kind of cutting board is much gummier than real HDPE, I have cut both and HDPE cuts like a dream where as walmart cutting boards I've tried gum up with anything but real fast travel and o-flute. I'm sure you could ebay or amazon a sample of hdpe for $20 and test it out, finding it locally is always the best if you can. The stuff I have is "starboard" leftover from a business I had, cuts great. Gary
Yeah, HDPE or starboard is what I would have suggested as well. I just checked Tap Plastics and 3/8" thick 12 by 24 inch piece was only $22.50. So it is not horribly expensive and it is very solvent resistant. The Tap Plastics I have near me sells scrap at $1.50 per pound. Scrap is basically anything with a dimension in one direction of less than 12 inches. I find a lot of great deals picking through their scrap bin. You could buy a smaller scrap piece to test it out.
I'm going with this next time I redo my spoilboard. https://www.menards.com/main/buildi.../blkhdpe48x96x220/p-1561703293089-c-14048.htm
I've used HDPE scrap from TAP/E-Plastics for spoilboards and light fixturing with 6061 pieces. Works well. Be cautious about RPM when surfacing as with a large diameter bit high RPM tends to produce more heat. Stands up to Way Oil, WD-40, Tap Cutting Oil, and PAM Spray as coolant/tool life extenders with 6061.
Having machined phenolics at my previous job, I would never want to use them for this. The resin used in those contains formaldehyde and it tends to come off as dust and not chips. I'm not certain that it will have a negative health implication, but I know for sure that formaldehyde is a carcinogen and dust isn't good under the best of circumstances. I suspect combining formaldehyde containing dust is just a recipe for health issues later in life. I would add my vote for HDPE. You could also look at UHMWPE, that stuff is basically chemical proof, although it can get pretty pricey.
