End Mill sliping

[rgray]

but can't you use a proper end mill holder instead of the collet?

In my book the collet is the proper end mill holder.

 

[Mitch Alsup]

Resharpened end-mills are often out of tolerance of the collet size they were originally.

 

[Bob Korves]

In my book the collet is the proper end mill holder.

I guess you never had one let the end mill suck down into the work... It would not happen with a Weldon end mill holder, used properly. Mounting in a collet can be more accurate, is quicker, and used less headroom, but it is really only suitable for lighter work. Weldon end mill holders are stout, but are also another place to add (or reduce) runout, and use up more headroom. I use Weldon holders whenever I have a job that will put a real load on an end mill or other tool.

 

[ezduzit]

I guess you never had one let the end mill suck down into the work...

That is how I learned. Fortunately it did not ruin the part or my work holding equipment.

 

[kvt]

Ok, How does having an end mill sharpened change the shank diam. Or am I missing something. I know it shortens them a little, and also if the diam is sharpened then that changes. Am I missing something.

 

[mikey]

You are not missing anything. Re-grinding an end mill does not include the shank.

 

[woodchucker]

Resharpened end-mills are often out of tolerance of the collet size they were originally.

Why would that be? They sharpen the flutes, not the shaft!
That would make no sense for a resharpening service to ruin an end mill that way.

 

[JayMcClellan]

I guess you never had one let the end mill suck down into the work...

Done that! Here's a video I made of a T-slot faceplate project a while ago and at 2:45 is where I discovered that my slot was a lot deeper than I intended, just got lucky that it didn't go all the way through and cut into the table. No matter how much I cleaned and tightened the R8 collet it just wasn't enough to keep this roughing end mill from slipping downward even though the nominal shank diameter matched the collet. This is what convinced me to switch to end mill holders and they've been working a lot better for me.

 

[rgray]

I guess you never had one let the end mill suck down into the work

Nope not yet.
And to think they now have heat shrink end mill holders.

 

[Bob Korves]

And to think they now have heat shrink end mill holders.

I will let that one gestate for a while and see what people think of it...