View Full Version : Verification please

21-05-2018, 08:43 PM

Finally took the courage and started to cut some wood this evening after so much checking and double checking of a new replacment build.
Using a CRP2448 with the 2.2kw spindle i did the model in Fusion then output to Mach3.

I want to cut 'sapele' and i have set a 10mm Bull Nose cutter in an adaptive cut at 8000rpm and 3800mm/min. This seems to be what i keep coming too with various checks.

So i start the climb cut and it goes down to 10mm doc and as far as i can see 2mm width (although in fusion it says opt load 4mm), it runs sweet along the grain but when it went across it chattered like hell and i had to stop it.

It may be that i have not secured it absolutely rock solid and its that, but tbh i had got it much more secure than any i have done before due to the nature of the beast i am now using (used a High-z 720 before.)
Can anyone who may have cut this type of wood before offer any advise please
thank you malc

21-05-2018, 11:51 PM
Sapele is quite hard. 10mm doc is probably way too much for an aluminium framed machine. Might work if your bit is razor sharp

22-05-2018, 08:30 AM
The cutter is brand new, i would not normally cut to this DOC but the rave is that adaptive is able to do just that so hence why i tried it out :-)
cheers for reply

22-05-2018, 09:27 AM
Machine rigidity is key to cutting capability.

22-05-2018, 09:47 AM
Machine rigidity is key to cutting capability.

Can i change any settings with sapele to compensate, the peice is 25mm h x 40mm w and 400mm l so its not a massive peice by any means, thanks

22-05-2018, 06:37 PM
Ball Nose Cutters all suffer from zero cutting speed at the very tip, have you considered roughing with a straight cutter and finishing with with the Ball Nosed cutter?

22-05-2018, 06:43 PM
I am using a Bull nose as opposed to a ball nose for the clearing operation, on a 10mm dia it only has 1mm corner rad

23-05-2018, 10:44 AM
Try the same cut but depth per level at 5mm
See how that works

23-05-2018, 06:39 PM
I am using a Bull nose

Might as well say 10mm endmill with a 1mm corner radius as no one will guess the corner radius.

Is it 2 flute?

How are you getting to your depth of cut? If you are not using a ramped or interpolated path to clear a starting pocket that's bigger than your end mill then any cut from the start point is full cutter width, not adaptive.

23-05-2018, 06:58 PM
I ordered it as a Bull Mill specific for the rail and i figuered an end mill might be too harsh....hmmm
Anyway, i lead in/out both vertical and Horizontal of 1mm on a helix ramp, and an angle of 2 degrees the ramp dia being 7.5mm.
I had to redo the whole drawing so am now only just back at the cam setup stage, i hope to create and test the new toolpath tonight with a doc of 6mm (sorry battwell i had already decide on 6 for some reason but at least i am close :-) ) and width cut of 2mm.
Cheers Malc