Thread: metric end mill in imperial R8 collet

Termite's one of our "special" members. Treat him as you just have, or put him on ignore. From a time and value proposition, I suggest the latter.

Originally Posted by dspahn

I'll be honest. I hadn't considered that option. I'm assuming you're speaking from personal experience here.
And while I appreciate all of the replies, I'm pretty sure my tolerance for pain and discomfort must be lower
than yours, and as such, I think I'll opt to remain a hobbyist and not try this "solution". Thanks though!

Oh, you don't HAVE to "DIY" that!

Just try getting suppliers to ship, customers to pay, material to meet spec, coolant to not stink, air and hydraulics not to leak, machines to not break or their power go out when you have a deadline - never any OTHER time... "etc".

... and it will FEEL that way!

You didn't already get the scars in a "Day Job" working for others?

At least when you've started your own shop or retired and gone "Hobby" you get to choose the BRAND of sharpish intrusions!

"Timing" remains pure luck!



I'm quite serious about using Weldon-"style" side-lock milling-cutter holders and NOT R8 collets for endmills, BTW. No flat on the endmill? Just kiss'em with a grinder. They need to respond to a setscrew's influence. Not be perfect.

Far less risk of push-back, pull-out, and ta da.. tons of endmills have on-size shanks that fit so you don't need as many sizes of holder before it is handy AND economical to have several that KEEP their commonly-used cutter for lots of frequent tasking.

You could have a set in US.. add ONE in 6 mm metric?

Or you could easily put R8-tailed ER 16, ER 20, ER 32 up for small money?

THOSE collets have a full 1 mm collpase range and still grip better than R8. A mere handful of collets and you have covered all of US, Metric, and even ODD sizes of DIY tooling. Plus changing with a spanner right in front of your nose. No need of a stool to climb up and wrench the drawbar as often.

Just because you are a hobbyist does not mean you have UNLIMITED time. There's always other stuff to do, same as there is for those where it is a full-time job.

OK, you DO know that they make metric sized end mills with English sized shanks, don't you?

Here is just SOME of what's available from only ONE supplier.

https://www.mscdirect.com/browse/tn/...tric+end+mills

I can see you will get along just great here.

Welcome to the nut house!

Originally Posted by dspahn

I'll be honest. I hadn't considered that option. I'm assuming you're speaking from personal experience here.
And while I appreciate all of the replies, I'm pretty sure my tolerance for pain and discomfort must be lower
than yours, and as such, I think I'll opt to remain a hobbyist and not try this "solution". Thanks though!

Originally Posted by EPAIII

I can see you will get along just great here.

Welcome to the nut house!

Uh not so fast! "Bollocks" are not until he's done his Journeyman's ticket!

Apprentices are limited to razzing the arse!

Originally Posted by EPAIII

OK, you DO know that they make metric sized end mills with English sized shanks, don't you?

Yes. But the end mill I'm trying to hold is a 6mm 60 degree dovetail cutter which MSC doesn't even sell. Nor does McMaster. I don't even have the end mill in hand yet (which makes the rectal insertion that much more difficult). The ones I found that fit my budget are import from Ebay. The listing doesn't say what the shank size is. The seller hasn't answered my question. So it might be imperial, but I doubt it. But, with the sleeve idea, no matter what the size is, if I don't have the correct collet, I can make do without having to wait for one to be shipped.

Originally Posted by EPAIII

OK, you DO know that they make metric sized end mills with English sized shanks, don't you?

Here is just SOME of what's available from only ONE supplier.

https://www.mscdirect.com/browse/tn/...tric+end+mills

Funny..:

MSCdirect.com is currently not available for your use.

This is what one gets for crticizing the bastids over prices and policy?



Or do they refresh their catalog DB at Oh-dark 5 AM, Eastern TZ?

"Sufficeth to say.." PTStools.com as an example that ain't broken:

One selects on shank TYPE (flatted, etc., Metric / US, etc.) ... as well as on material ... and all the MANY OTHER "working" characteristics desired for the sharp parts of an endmill.

And/or puts by a goodly selection of holders (I DID say "side lock"?) and then attempts to live off whatever scrap, bargains, good bad, indifferent.. "mystery cutters".. that eBay has to offer, used, imported, or reputable.

Be aware.. SOME such "bargains" can easily COST a person FAR more than they save!

Not just wasted time. Ruint work. Damaged toolholder, vise, or table. BAD habits learnt instead of GOOD habits learnt.

Even personal injuries.

Even very good cutters do not work well if the geometry, flute-count, or coating, if any.. is just plain "poor match" for the alloy and operation being worked, and whether dry, flood, droplet, or mist coolant.

All hands here were naifs at one time. More than just a few even further back than my mere 60 year at it.

"Learning" is grand when you are impoverished.

One of the few things in life no one can take away from you!

Unless, of course, you go nucking futs and rant cemember a tam ding!

Originally Posted by EPAIII

I can see you will get along just great here.

Welcome to the nut house!

Yeah, he's got the thick skin PM requires...

Originally Posted by dspahn

Yeah. I knew I'd catch a bit of business for asking such a rookie question. But I figure that's just the price of admission to get help from a community with countless years of expertise and knowledge, given for free, and willingly. So it's all good. I figured it would work (assuming the sleeve is created well), but it's reassuring to know that the people who really know have said it's an okay thing to do.

We're all a bit mad here, .and mostly OK, ....well those of us who take their meds.

Originally Posted by Limy Sami

We're all a bit mad here, .and mostly OK, ....well those of us who take their meds.

?? You are not "mad". Just a bit around the bend. Left bend, of course. Labourite thing. It doesn't make you a bad person. Not ALWAYS, anyway!



This dam' COVID crap?

We ain't even been able to enjoy the Caribbean, let alone our usual hols on the med!

Eldest niece has even had to defer a wedding all set up for Okinawa.



Well it would be her third.

"First Child" thing?

We do tend to be a tad more "expiry"-mental?

See what I mean

I usually make adapters 3/4 OD then drill and bore my ID to size and use set screws to retain the tool.

why not just buy a 6mm R8 collet? they are like $15. call local tool suppliers.

Originally Posted by BT Fabrication

why not just buy a 6mm R8 collet? they are like $15. call local tool suppliers.

"Virtue signaling".

"I am POOR.. because I make suboptimal decisions."

Youse' "wiser guys" OWE me!

Get it right? You might even become Pretzelbent... of the Beg-nighted Scrapes.

I have made many adapter bushings over the years, for end mills ,drills, grinding wheel shanks,ect.I have done this when I need it right now.Edwin Dirnbeck

Originally Posted by dspahn

I'll be honest. I hadn't considered that option. I'm assuming you're speaking from personal experience here.
And while I appreciate all of the replies, I'm pretty sure my tolerance for pain and discomfort must be lower
than yours, and as such, I think I'll opt to remain a hobbyist and not try this "solution". Thanks though!

That's an excellent choice!

Originally Posted by Hardplates

That's an excellent choice!

Since WHEN did he HAVE a choice?

Yah wants a "choice" yah have to buy tooling. The wronger the better!

So as to insure it is a never-ending process.

You wouldn't eat a yearling steer "all at once" would you?

Trouble enough hunting wild-caught Haggis whilst still on Mother's milk and small enuf' to dress-out - after boning and tanning the hide - to a meal for one.

Ignoring much of the above and trying to address the issue seriously, R8s are some of the worst collets known. Unless the shank is an exact fit to a very tight tolerance, it will grip only at one of the clamping areas or the other. In a heavy cut the shank can tip slightly and walk its way out. I got rid of my R8s and bought a mill with a 30 taper spindle. I would prefer a 40 but that was the largest I could get in a BP clone. Before that, I used end mill holders of the types mentioned. You are not strong enough to tighten an R8 to hold a four flute 3/4" carbide cutter on a heavy cut. My CNC mill with a 40 taper spindle and TG100 collets would break the cutter before they would let go.

Bill

An extra on adapter sleeves-I do the cut right thro,and two more almost thro-makes the sleeve more flexible. Re R8 collets,I only use them for light work. Anything heavier and for LS cutters I put my trusty Clarkson Autolock up-no cutters going walkies out the collet!

Originally Posted by TedinNorfolk

An extra on adapter sleeves-I do the cut right thro,and two more almost thro-makes the sleeve more flexible. Re R8 collets,I only use them for light work. Anything heavier and for LS cutters I put my trusty Clarkson Autolock up-no cutters going walkies out the collet!

PDQ-Marlin with sidelocks.. on B&S #9 with drawbar?

PDQ-Marlin with sidelocks .. on 40-taper with drawbar?

Endmill ain't a fit to the sidelock?

Go and use a different endmill that IS!

They made more'n ONE of the fool things, yah?

Are-ates are for chewing things up. That's why they CALLED them "Are Ate"!
Or the Marlin's "Pretty Damned QUICK"

Talk about a wicked sense of humour? "Are Ate"?

Them old boys didn't miss a trick "back in the day"!