Cambam / milling Alu

[dudz]

I think I have got the hang of Cambam now with wood, and I'm not to bad with Mach3. I wanted to do a test on a small piece of Aluminium 8mm thick. 1mm @ 550mm/min 12-13K , Feed plunge +30 (4mm single face endmill) and Z zero set. First I used one of the pocketing wizards in Mach.
When I pressed the cycle start on Mach3, the endmill plunged hard into the alu , it seemed far to hard, so I pulled the Z up, and inspected the piece. Very rough circular hole, 1mm deep. Doesnt seem like it wanted to cut at all. What am I doing wrong here ?
Another thing. In cambam it asks for plunge feedrate. What should this be set to for alu ?

[JAZZCNC]

Don't plunge into Ali it knocks hell out the machine and cutter.!!

That feed rate is a bit slow for 4mm SF try 800mm/min has a starting point. Not sure what feed plunge +30 means.? But in any case plunging into Ali is a bad idea and far better to either spiral or ramp down to depth before cutting. I spiral down slow around 300-400mm/min in Alu.

Here's 2 bits of code to try using a spiral entry both same except ones conventional milling and the other Climb milling so you can see difference.!
cutting 50mm Dia circle, 3mm deep, 1mm Doc, 4mm S-flute cutter, 15000rpm, 800mm/min, 400mm/min spiral down. Z zero top of material.

Edit: Rapid height =10mm

[dudz]

Ah, OK........Thought there must be something wrong. I will try the codes this week and let you know my results.

Thanks !

[dudz]

I have not tested this yet, as I am changing my X axis rails and cutting bed.

Using CamBam, how do you set the cutting profile to "spiral down" instead of plunge ? I cannot find any way of setting a "spiral or ramp" down move. The plunge feedrate is set as default to 300. The only thing I can find is the menu "Lead in move" with the 3 settings....Spiral angle / Tangent radius and Lead move feedrate. I haven't got a clue how much to set these at (if this is it) and/or if I need to change the plunge rate to 0 ??

[JAZZCNC]

Sorry don't use Cam Bam so not much help.! The fact the lead in move has a spiral angle option suggests it does but how I've no idea.! Sure it will be a simple selection option.?
Are you using the free version.? If so then it may be disabled.

[dudz]

Yes I am using the free version. I have posted the same question in the Cambam forum. Thanks anyhow