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View Full Version : No good reason: 1/4" End Mill holder?



Arthur.Marks
01-09-2014, 04:39 PM
Genuine question: can anyone give me one truly useful reason to own a 1/4" EM (Weldon/setscrew type) tool holder?


The only reason I ask is because there is a NOS one for sale of a superb make, and I will probably never see another. That may be reason enough for some, but I can't fathom the reason it wouldn't sit in a drawer until kingdom come. I basically stick to quality, name-brand cutting tools. Not a single manufacturer even makes one in HSS. Carbide I run in collets--especially when that small. The only name-brand mfgr. I can come up with that offers 1/4" HSS shanks is Clarkson-Osborne, but those are threaded Autolock cutters. In the US, they're comparatively expensive and rare. KBC is the only major distributor that even handles them, AFAIK. So why on earth would an extremely high quality toolmaker offer a 1/4" EM holder in the first place:confused:

lakeside53
01-09-2014, 04:52 PM
I use mine all the time. I have a few sizes, but the 1/4 inch specifically is preloaded with carbide. When I change tooling and then back the tool length offset did not change so no resetting of Z required. If I remember to number them and write down the length... the tool number in the dro will automatic set the tool length offset.

JohnAlex141r
01-09-2014, 05:51 PM
I had a clarkson one; 3 imperial collets, wrench (spanner?).

Gave it away to a fellow club member - it came with a mill I picked up, but sat in a box for well over a decade without seeing the light of day.

I don't know if the recipient has even used it!

Just my own observation;

John.

tyrone shewlaces
01-09-2014, 05:51 PM
The advantage to Weldon shanks over split collets is that it will not allow an and mill to pull out. In operation, the flutes on end mills apply a pulling force on end mills. Carbide shanks are obviously pretty hard and polished so can be relatively slippery. As long as there is a flat on the end mill shank (which you can grind into it if it's not there from the factory) and you install it correctly, the set screw will hold the end mill very well and not allow it to spin or pull out at all.
Having said that, I am happy with either setup and don't worry too much about the end mill moving under normal conditions. Over the years I have experienced a problem or two due to a split collet allowing an end mill to pull out a bit which obviously changes the depth it cuts. But I've used split collets a ton and it's only happened a couple times or so.
Personally I like Weldon shank setups and I'd pick it up if it fit my mill and was a good deal. Even if you have one already, nothing wrong with having two 1/4" holders. Actually I feel like it would be difficult to have too many mill holders of nearly any kind.

Oh yea, the Weldon type holders usually have a much smaller head than a split collet head giving more clearance which is sometimes handy.

Gary Paine
01-09-2014, 06:29 PM
The advantage to Weldon shanks over split collets is that it will not allow an and mill to pull out.
Oh yea, the Weldon type holders usually have a much smaller head than a split collet head giving more clearance which is sometimes handy.

I second both these statements. One bit that I find doesn't grip sufficiently in a collet is a dovetail bit. The pull out forces are too strong. Most of my dovetail cutters are 1/2 inch shank though.

On the smaller diameter mills, the extra clearance around the cutter I find useful a lot.

lakeside53
01-09-2014, 08:15 PM
If you are having trouble with your dovetail tool slipping, grind a small flat on the shank.

Gary Paine
01-09-2014, 10:23 PM
If you are having trouble with your dovetail tool slipping, grid a small flat on the shank.

How does that work with a collet? I thought we were discussing reasons for having a Weldon type holder, which works fine with a dovetail cutter.

Arthur.Marks
01-09-2014, 10:58 PM
My original point was that there are no 1/4" shank, Weldon flat end mills available other than a few generic, low-cost ones. Name brand, domestic manufacturers all use a 3/8" Weldon shank for their 1/4" HSS end mills.

mike4
01-09-2014, 11:17 PM
I still have about 200 1/4 shank end mills some of which I have ground a flat on .
When making a part I find it easier to preset the endmills in several holders and just change holders , at around a minute per change its quicker when working at the mill all day .
Michael

lakeside53
01-09-2014, 11:21 PM
How does that work with a collet? I thought we were discussing reasons for having a Weldon type holder, which works fine with a dovetail cutter.


it doesn't. I completely misread your post!