Older used endmill will not fit new endmill holder;

This is not a shrink fit holder is it?

Wire wheel shouldn't touch the HSS of an end mill. Wires aren't hard enough. And HSS rarely "dents" or "dings". On the other hand, the holder, if it is a standard holder with set screws it won't be as hard as the end mill, and can be dented or dinged. As others have said, try other end mills......mic the one that won't fit and compare it to other new ones. It's unlikely that it is oversized, IMO. Trouble is more likely in the holder. Do you have a flap-stick?
 
Tony Wells said:
This is not a shrink fit holder is it?

Wire wheel shouldn't touch the HSS of an end mill. Wires aren't hard enough. And HSS rarely "dents" or "dings". On the other hand, the holder, if it is a standard holder with set screws it won't be as hard as the end mill, and can be dented or dinged. As others have said, try other end mills......mic the one that won't fit and compare it to other new ones. It's unlikely that it is oversized, IMO. Trouble is more likely in the holder. Do you have a flap-stick?
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Thanks Tony,
no, where do i get a flap stick?
thanks,

Jon
 
A flap stick, or simply a flapper, is something you make. Everyone ought to have one in their toolbox. Take a piece of 1/4" round stock and hacksaw a slot about an inch long into one end, splitting it. Then you can fold a piece of emery cloth of whatever grit you need and cram it down in the slot you sawed. Put this in your air motor (die grinder) and if you make the cloth length just over the diameter of the bore you are working in, fold it slightly to get it in the bore and hit it with the air. Stroke it like a hone. Fast or slow, as needed, coarse or fine, as needed. If there is a ding on the mouth of the holder, you can pull the spinning flapper just out to the edge, and it will try to push itself all the way out once you get about halfway out, but it will nicely round off the bore/face edge.

Being hardened, the holder won't easily give up size, so I wouldn't hesitate to go with 80 grit and just flap it enough to give it a little shine first, and maybe hit the edge a little. Just be aware that this will warm up the holder if you run it fast for very long and then if you try the end mill and get it in there......it may stick when temps equalize. Just make sure it's back to room temp before test fitting. And as before, check a couple of other end mills to make sure there really is a problem with the holder.

I can post a pic of one of mine if needed. I have several of different lengths. Quite handy. Until you get used to being slapped around by whizzing sandpaper, you may want to wear gloves while holding the object you are flapping.
 
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Good chance it's a 25 mm end millholder alot of the imported stuff is mismarked if that's the case it would be .040" undersized
 
Like Tony said every one should have should have flap sticks of various sizes in there box and roles of emery. I have a 1/4" steal rod for the die grinder. And several size wooden dowels that I use for polishing the id of parts on the lathe.
 
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