Silly question but.... I just got a piece of 12" x 12" x 0.060" sheet of PEI/Ultem for my Delta printer. I was thinking about using my newly assembled super duper C-Beam machine to cut it to the 180mm diameter disc that I need for my printer. I also picked up a sheet of 12x12 3M adhesive to go with it. Any thoughts on how I should tackle this? I have a small variety of 1/4" shank bits for the DeWalt 611 (60 and 90 V-Bits, 3/8" length 1/8th" bit and a 1/4" 2 flute straight) Random thoughts: Cut Ultem bare with a bit of carpet tape to secure? Apply 3M before or after cut? Fast or slow feed? Any advice would be greatful
Hi, for good results always clamp parts to be milled tightly. I looked up PEI/UTEM as i do not knwo it firsthand. Seems to be a thermoplast, meltingpoint, depending on specific type, between 150 and 200 decC. So i would go about aprox like milling POM: Always use an "as new" shrap milling bit. High feed, relatively slow rpm, depth of cut ajusted suiting your machine and router.. make a test g-code and adjust ( a straight line somewhere in the cutoff area is enough) Use a single or two flute straight bit.. starting point i would suggest 9-11000 rpm, 1200mm/min feed on a 4mm bit try shallow cuts first and adjust rpm or feed, than go deeper as much your router and machine can handle. starting with shallow cuts hardly anything harmfull will happen. maybe a bit of smearing /melting but that is easylie adressed by reducing rpm or increasing feed imediately just be prepared.. cooling is always good, but i cannot suggest for no experience with UTEM For acrylic i used "vinegar" -ascid (industrial/cleaning type 25%) much dilluted in water .. but i am not shure if it attacs your material... good luck with it Flo
4mm Single flute upcut spiral 8000 rpm 2800mm/min you should be fine. Straight flute will likely give you lots of chatter imo. Have the machine drill fixing holes to spoil board before contour operation, will keep chatter from vibrations in material down.
