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View Full Version : Group Buy - End Mills?



Tenson
18-05-2012, 12:58 PM
Hi guys,

I got one of the X5070 Blue end mills from Cutwell tools recently. It is a 6mm dia. cutter with only 6mm flute length, but it has a very slightly reduced shank above the flutes so it can reach to cut 15mm depth, provided you take 6mm passes.

I think this works really well because it is super stiff and gives a great cut quality. However they are expensive!

I was thinking about getting some of the 6mm K2 stub end mills that have 8mm flute length and then having the shank reduced above the flutes so it can reach 20mm (standard they have 6mm dia. cut and 6mm shank so will rub slightly if you cut deeper than the flutes).

Would anybody else be interested in these? I guess the price could be better if I buy more.

JAZZCNC
18-05-2012, 02:43 PM
Hi guys,

I got one of the X5070 Blue end mills from Cutwell tools recently. It is a 6mm dia. cutter with only 6mm flute length, but it has a very slightly reduced shank above the flutes so it can reach to cut 15mm depth, provided you take 6mm passes.

Unless your cutting steel or hardened steel at high speeds then using these cutters is a waste of money and they are actually less affective in ALi than the cheap chinese 5 for £25 from ebay.
Much much better option if cutting Ali or plastics and not much more expensive than X Blue range are the Karnasch 1 flute. They have flute lengths upto 32mm in 6mm Dia. The cut quality is absolutly fantastic and they last age's in Ali, far far longer than any other cutter I've used.! . . . but they are expensive and you pay for the quality.
Basicly I buy the cheap Ebay cutters for general use and the Karnasch for finishing or better jobs.



I was thinking about getting some of the 6mm K2 stub end mills that have 8mm flute length and then having the shank reduced above the flutes so it can reach 20mm (standard they have 6mm dia. cut and 6mm shank so will rub slightly if you cut deeper than the flutes).

Why.??? Just buy the Ebay cutters which have 22mm flute length.! . . Not a good plan to start hacking bits off what are not exactly cheap cutters they will be severly weakened.

Tenson
18-05-2012, 03:02 PM
I haven't tried the single flute eBay ones yet, though I have ordered some. I have tried the 2 flute and 4 flute K2 and the 4 flute X5070. I found 4 flutes gives a better finish than 2 flutes and the shorter flutes of the X5070 give better finish than the longer K2.

JAZZCNC
18-05-2012, 03:28 PM
I found 4 flutes gives a better finish than 2 flutes and the shorter flutes of the X5070 give better finish than the longer K2.

Single flute give better finish than 2, 3, 4 flute due to better chip clearence and not recutting chips which often happens with 4 flute if the feeds and spindle speeds are not spot on.
It's much more critical S&F are spot on giving correct chip load when using multi flute cutters.! If not they wear quickly due to heat and the finish gets rubbish fast.!!

Shorter cutters will always tend to give a better finish anyway due to less tool flex. I always do a full depth 0.1mm finish pass when machining Ali and wanting decent finish so even the cheap chinese cutters give a good finish.

Tenson
18-05-2012, 04:22 PM
If chip removal is the key to good finih, then a 2 flute cutter would give a better result than a 4 flute, wouldn't it? It didn't for me.

JAZZCNC
18-05-2012, 04:44 PM
If chip removal is the key to good finih, then a 2 flute cutter would give a better result than a 4 flute, wouldn't it? It didn't for me.

Chances are you didn't have the correct chipload then.? It makes a big difference and when you find the correct chipload it's clearly visiable in both finish and sound.

Jonathan
18-05-2012, 04:51 PM
Those cutters are advertised as:

'For ultra high speed machining of high hardened materials.• Suitable for dry cutting and high speed cutting.'

So they're meant for machining hardened steel without coolant at a high speed ... nothing to do with machining aluminium. The coating only helps when the cutter is operating at a high temperature (which is not the case when cutting aluminium), hence the cutter will actually achieve a higher material removal rate without coolant since it allows the coating to reach the higher temperature where it's properties (hardness etc) change and most of the heat goes into the chips.


If chip removal is the key to good finih, then a 2 flute cutter would give a better result than a 4 flute, wouldn't it? It didn't for me.

Yes it will if you use the right feed and speed. The only situation where you might get a better finish with a greater number of flutes is on a finishing pass with limited spindle speed.

Jazz has said it all really - more space for the chips with a single flute and the chips are ejected more readily.

Wait until you've used the 6mm single flute cutters ...

JAZZCNC
18-05-2012, 05:08 PM
Those cutters are advertised as:

'For ultra high speed machining of high hardened materials.• Suitable for dry cutting and high speed cutting.'

So they're meant for machining hardened steel without coolant at a high speed ... nothing to do with machining aluminium.

These are the cutters I use for cutting steel and they work great with my WC spindle at 10K and last ages but I have tried them on Alu and they don't like it no matter the speed & feed. I've tried all combinations deep DOC + slow feed high rpm and vise versa etc and which ever way they just don't like Ali.? . . . Not surprising really has there not designed for it.!

To be honest I find the Alu pow HSS 1 flute give a great finish, better than carbide, but they don't last long enough.

Tenson
18-05-2012, 09:23 PM
Chances are you didn't have the correct chipload then.? It makes a big difference and when you find the correct chipload it's clearly visiable in both finish and sound.

That's probably it. I'll wait until I get my main machine up and running to make any serious judgments then. I need some metal parts cut before I can make anything more, I think I'll put a request in the market place section.