Very fast machining in ply with a Multicam Trident CNC router
Hi there, new proud member of Wodwork Forums here, glad to be on board!
I'm currently renting time with a Multicam Trident router over at Fab9 in Footscray, VIC. It's a combination router / sign cutter with a 6.7HP spindle and costs $50 an hour to use.
I'm cutting a large number (12-16) of small two-side 3D profiles out of 18mm plywood, making a total of 24-32 cuts in total. This means that doing the cuts quickly is critical to the viability of the project. If each side takes 2 hours to complete, the total cost of the project is at least $2,400 in router time alone, which is unacceptable. If each side takes 20 minutes to complete, the total cost is only $400.
So my big focus is on dramatically improving machining time, and I'm willing to sacrifice the quality of surface finish to this end. I have a 1/2 diameter 3 flute down cut roughing bit with a 3mm corner radius that I'm hoping will be able to fly through the plywood really quickly, and also do 3D acceptable profiling.
My question is this - does anyone here have experience using high feed rates (7200mm/min +) using a roughing bit in plywood? I guess I'm looking for validation that this is possible / safe with the right setup, and confirmation that the torque of my spindle is up for the job. Any other info along these lines would also be massively appreciated!
As Kryn has rightly pointed out, the big unknown here is the rigidity of the machine. There is no specification for rigidity that I can find, so if that is the primary limiting factor for feedrate, how do I determine it? Simply by running successively faster feeds and listening out for chatter?
The ply is furniture grade birch, 18mm.
Thanks in advance,
Jez