carbide endmill

Hi all.

I'm sure this has been asked before but my searching via the generic search on this site has yielded little.

So what is the deal with solid carbide endmills ?

Pro's ,con's and thoughts .

Are they worth a look ?

They seem to be getting cheaper and fleabay has millions of listings .

IAN

Rule 1: Never buy cheap unbranded cutting tools of any description, not just end mills. They're a complete waste of money.

Rule 2: see rule 1

I've settled on using uncoated solid 3 flute centre cutting carbide cutters on my CNC mill for most jobs, plus coated ones for stainless steel. I also use them for general work on the manual vertical mill. I use Garr cutters, as that's what my local professional tool outlet stocks. I use 6mm (~£8) and 10mm (~£18) as standard.

Here are a few pointers, with some repetition:

Carbide is about 3 times stiffer than HSS, so less problems with cutter deflection.

They are harder than HSS, but not as shock resistant, ie, drop it and it's badgered. It's one reason why I've bought a Haimer Zero Master for setting the CNC. If you try and 'touch-off' the work with a carbide cutter, and slightly overshoot, the cutter will chip, unlike HSS which will probably just indent the work.

They can be run fast; I use 2-3000rpm and 3-500mm/min feed on low carbon steel and 3-5000rpm and up to 900mm/min feed on aluminium. For aluminium the limiting factor is the CNC mill, not the cutter.

I run carbide cutters dry on the manual mill, and with flood coolant on the CNC mill, mainly to help with chip clearance. There are few things that will badger a cutter more quickly than recutting swarf. I've never had a problem with cutters chipping when using flood coolant.

I still use a lot of HSS cutters, especially on the manual mill, but carbide is now my first choice for general work.

Regards,

Andrew

They can be expensive for jobbing work but onece you have used them you will reach for them first.

They do last longer and seem to eat the work. The finish is better too.

Clive

Hi all thanks for the replies .

I will have a look a these and look at a reputable brand .

I dunno about forking out 100 quid + for a cutter tho - probably be to scared to take it out of the packet

I noticed in the picture John posted that one of these cutters has a serious helix angle !

IAN

Edited By SLOTDRILLER on 01/09/2012 01:42:41