And this is why you ask questions here. First I had to look up ACM, I am assuming it is “Aluminum Composite Panels” … this stuff looks very interesting. Amazon has a 30x30x1/8" for $40 which should be a rough estimate.
I should also add you sent me down an ACM rabbit hole…I will be back in a week
I believe the thickness tolerance is across the sheet similar to how cast acrylic can vary by as much as 10% within the individual sheet.
For wood products it’s worse because the standards are measured at point of manufacture but environmental conditions can radically impact the dimensions when you finally get to using it in a project. Kind of why for most CNC work I don’t chase resolution to the thous. For projects that require high precision a mill and metal is more appropriate.
Yes I recognize this could be an issue. What do you think about running the hardboard through a thickness sander first. We don’t really care about the actual thickness, just that it is consistent. (sand only the side that is not “tempered”)
How do you plan to lay out the hardboard on your machine? Do you have a QCW for your Foreman also? I’m imagining strips of hardboard covering the “slats” that run parallel to the t-track / y-rails.
For the cost of hardboard, I’d say try it all. You could even try facing the back side with your machine, although maybe that’ll be a disaster. I’ve only ever cut straight through hardboard with a CNC while making templates, so I can’t speak to adjusting thickness by any means.
Might also be worth measuring to see if it’s really that variable in thickness. I’m willing to bet it’s more consistent than advertised, but again WTF do I know about hardboard. Overall, I’m pretty inexperienced with the stuff.
My table is made out of pine, on casters surprisingly enough. But it will have a few sand tubes tucked in to increase the mass. I had the QCW for Journeyman, and while it was fine, I decided to spend those pennies on the ATC & Spindle.
I have an 18/36 thickness sander, so a few quick passes and the hardboard should be pretty close to the same thickness ( cough, cough damn dust)
Yes, my table will have MDF slats with T slots. With a 20 mm (MFT like) hole pattern, with hole for 1/4" gage pins for alignment… still debating in the T nuts.
I would see a … oh 30x30 piece of hardboard being clamped at the edges in the T track and then I am making something like:
Universal Aluminum Fixture Tooling Plate – Saunders Machine Works
So the center of the hardboard would have 2’ish studs to go into the fixture slots, to clamp everything firmly.
Is any of this implemented yet? Nah. But gathering ideas to minimize my stupidity.