Why can't I find a 1/4" R8 mill end holder

I've checked the usually suspects, Little Machine Shop, Horrible Fright, Enco, for a 0.25" R8 mill end holder for my mini-mill. I have 2 items I want to buy individuals holders for and they are both 0.25".

Maybe, just Maybe, I could bore out a 3/16" to 1/4" but my mini-lathe isn't quite as accurate as I would hope it to be.

Any ideas??

Thanks, Rod

Reply to
Rod Richeson
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Reply to
Lucky Strike

Looks like 1/2" is the smallest common shank size for end mill holders in R8. However, you can get R8 collets in sizes much smaller than

1/4". Usual suspects have R8 collets, MSC carries 4 different brands in 1/4". Another solution would be to sleeve the 1/2" holder down to 1/4". Personally, I'd go for the collet, you probably won't be applying enough side force to walk the cutter out and you'd gain 3/4"-1" extra height over the table over the end mill holder.


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part no. BCV-75905M -- this is at the very top end pricewise, but it shows you they are out there. - GWE

Reply to
Grant Erwin

Not only do you gain height, but (more importantly, IMO) you reduce runout. Endmill arbors are nice for hogging as they don't typically allow the cutter to move, but they have more runout than a collet which is not good for smaller endmills.



Reply to
Robin S.

NOT true. 1/4" and 3/8" R8 end mill holders are available. I have several of each (some imported). Try a real machinst's supply instead of a discount import place. Granted, they will be more expensive there.

Dan Mitchell ============

Reply to
Daniel A. Mitchell

OTOH I've had problems getting little collet-mounted endmills close enough to the work. The spindle nose won't clear the clamping or the workpiece.

A collet holder lets you get down into a hole easier. I guess the best situation would be to have both collets and holders.

Reply to
Jim Stewart

ETM makes them - even 3/16 . Martin

Reply to
Martin H. Eastburn

--You picket three losers. Try MSC or IPS or Travers Tool.

Reply to

You can get them. I got two Collis EM holders from MSC, I think. After searching all over, I ended up paying $45 apiece for them, on sale! I really don't know any solution other than buying it at full price, unfortunately. I don't know why this one particular size is so hard to come by.


Reply to
Jon Elson

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