View Full Version : Long bits/endmills

23-03-2016, 08:17 AM
I've ordered myself a nice long 3mm ball-nosed bit for a relief carving project I'm working on. The flutes are 25mm and the overall bit length is 75mm. Shank dia. is 3mm.

Can anyone offer me any advice regards using one?

The nice man where I bought the bit from has said I need to be careful with it but he is experienced in metalworking and obviously wood is more forgiving. I'm practising with bits of Pine that I have kicking about but intend to be cutting the design in Oak and other hard woods.

23-03-2016, 11:35 PM
I'll add to this and say that I've been advised to run the bit as fast as possible with my feed rates at 0.015 per tooth.

I'm fine with the spindle speed :) but a little confused with working out the feed formula :/

23-03-2016, 11:42 PM
Your CAM software should allow you to set your job up with the required feed per tooth

23-03-2016, 11:44 PM
great news, the first thing I did was google it and lots of scary looking formulas requiring variables I had to google too :)

24-03-2016, 09:18 AM
Have a look at HSM advisor, entering all the material and tool criteria for your cut yields a set of baseline data, although it doesn't take into account machine rigidity with long tools the allowances for tool flex it's likely to be on the money,