Chipload and DOC for small endmills
What chipload should I use for a 3 flute 1mm endmill on aluminum, for slotting and for other cut widths.
I've been researching and found anything from 0.005mm to 0.02mm per tooth.
I really don't want to break this so I thought I'd ask here first...
Depth of cut I thought maybe 0.5mm for slotting, that might be a bit much though?
Re: Chipload and DOC for small endmills
Depends on flute length, spindle speeds and lubricant. What you got?
Re: Chipload and DOC for small endmills
Quote:
Originally Posted by
Robin Hewitt
Depends on flute length, spindle speeds and lubricant. What you got?
Flute length is small, maybe 3mm. I only need to cut down a maximum of 1.4mm though. It's HSS.
Spindle speed, milling machine is 2150rpm...so very limited for this size of cutter. If I bolt the router spindle to the milling machine when I get it that will get 24000rpm - so still less than optimal but much better.
Lubricant would be me standing there with a brush and cutting fluid. Maybe WD40 as it's thinner so should get into the flutes more easily?
Re: Chipload and DOC for small endmills
The slots I'm cutting are 1.4mm wide and 1.3mm deep. (see my Gcode thread and look at timing pulleys program if you want to know exactly what's what...)
Quote:
As a cutter that small is stronger radially than axially.
I think you meant stronger axially.
I think it's center cutting, not sure ... quite a big change to the code to do that but worth it I guess.
Where do you get the 0.01mm chipload number from, experience (if so good)? It's about the average value I found from checking various websites. I've used 0.025m chipload with 2mm 3 flute endmill successfully:
http://www.youtube.com/watch?v=p13LZ6IxmgY
(wrong title on that video!)
I may just grind a form tool to do this in the end, but it'll be nice to try it.
Experience! Only 7 years...much less than yourself I guess.
Re: Chipload and DOC for small endmills
Quote:
Originally Posted by
M250cnc
As you increase cutter diameter you can push harder but with only one cutter I would play it safe.
When drilling you can go slightly higher chipload.
You could use a proper drill to rough out the slot maybe use a 1.2mm drill.
Then use the mill to thin the web and cleanup the walls.
Higher chipload when drilling sounds logical due to being stronger axially, also I think the cutting edges on a drill are acute less acute angle so stronger ...
Anyway, I like the idea of 1.2mm drill since I've got plenty of carbide drills that size and one HSS. Due to the point angle on a drill I could actually squeeze in 1.8mm drill.
Time to add a drilling cycle I guess, more calculations...
Thanks for the advice.
Re: Chipload and DOC for small endmills
If you are cutting teeth, have you considered a small slitting saw in a wide arbor?
They may bend but they don't break (unless you have a Z whoopsy) :naughty:
Re: Chipload and DOC for small endmills
Quote:
Originally Posted by
Robin Hewitt
If you are cutting teeth, have you considered a small slitting saw in a wide arbor?
They may bend but they don't break (unless you have a Z whoopsy) :naughty:
Yes I have considered that - it would be a lot faster. I've got a 1mm slitting saw that would do the trick.
The reason I've not done it is I've not got a tailstock for my rotary table and the pulley would have to stick out a fair distance for the slitting saw to clear the rotary table chuck. Maybe I'm being overly careful...
One nice thing is I can use almost the same gcode with slitting saw, just need to swap Y and Z axis.
Re: Chipload and DOC for small endmills
Quote:
All my experience comes in an industrial environment over 20 years.
dont let that intimidate you jonathan, in this country it could easy mean spending 15 years with a cup o tea in one hand and a fag in the other and wondering which hand to scratch your arse with :rofl:
looks like you missed a tooth on that pully?
parts for my 4th should turn up any day now :)