Could someone please tell me what speed and feed rate and speed you use to cut 1/2" Ultraboard with aluminum face. I'm using a 1/4" down cut bit @ 10,000 RPMs 1 IPS and the aluminum tears out the foam. Not a smooth edge!
Posted by Graham Parsons (Member # 1129) on :
John,
I've got the best results with Ultraboard by making two passes - the first to just the depth (thickness) of the face, and the second pass to the full depth of the board (½") Routing the face away first, and cutting the rest in one seems to keep the damage to the foam to a minimum.
[ September 18, 2007, 07:38 PM: Message edited by: Graham Parsons ]
Posted by John Arnott (Member # 215) on :
Thanks Graham. . . . .Are you using a down bit?
Posted by Graham Parsons (Member # 1129) on :
John,
Although I usually prefer an upcut bit because of the ease of chip removal, for Ultraboard or anything with a face material, I would use a downcut spiral to prevent the face being separated. Also, I would suggest a higher rpm - 14K?
Edited to say I have tried it with a downcut on the first pass, and an upcut for the rest and these seems to give pretty good results, albeit a bit fiddly on the bit change (unless you're Dan, of course! )
[ September 18, 2007, 09:15 PM: Message edited by: Graham Parsons ]
Posted by Joe Crumley (Member # 2307) on :
Graham's suggestion for increased spindle speed will certainly help. Don't be surprised if there is some inconsistancy with the aluminum not sitcking to the board. And after you finish the profile cuts it would be advisable to check the aluminum edges for lifting.
I've haven't had mixed results with their product. In damp weather the aluminum seems to give up the ghost.
I'm proud of you for making the move to a CNC. This is a tight community thats willing to help. Keep us informed with your progress.
John, I haven't used UltraBoard so I may be talking out of turn here but we have cut similar items. What we usally do when cutting foam with no tear out is first do a roughing cut with a up Sprial about .03 larger then the finished product and just about all the way through. On .5 inch will route .45 down. Then Switch out the bit to a very sharp straight edge bit Cutting conventional (Cutting Edge into the material) then do the final finishing pass going all the way through the material and into the sacrifice. Just like any Routing a good sharp bit keeps the edges clean. Hope this helps.
Posted by John Arnott (Member # 215) on :
Well, This is how I ended up do it. I bought a "up" 1/4" bit and cut in 1 pass @ 14,000 RPMs and .5 IPS. It lifted the metal out perfect and a smooth edge. I just held it down with my fingers at the very last, (no tape). Now I'm ready to cut the real job!
Posted by Bryan Quebodeaux (Member # 48) on :
Most of the time I rout 1" Ultraboard and like some mentioned before, I always rout the face first and the foam next. We laminate our choice of substrate to the foam ourselves (mostly acrylic and aluminum). After nesting the job I will cut out the sized substrates and then laminate using 3M Super 77 adhesive spray. I tried waterbased formica contact cement with good results, 3M spray is a bit toxic but quick and very dependable. Afterwards I apply application tape to the backside of the laminated product and rout down to the tape pausing the router after 2 or so letters to apply silicone spray to the bit, not actually spraying the bit but spraying a rag and wiping the bit. That seems to keep the bit slick so that no foam builds up while traveling and ruining the returns. I prefer to use 1/8" upcut short bits for the top surface and 1/8" upcut long bits for the foam. I use 1/8" so that any inside corners have a minimal radius. After a bit of trial and error I found that feed rates using my Sabre 408 and Artpath of 19000 R.P.M and 2 IPS works for me. -Just my .02 cents
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