End Mill Holders for Atlas MFC

[JPMacG]

I have been less than happy with running end mills in the MT2 spindle socket of my MFC. The MT2 lacks rigidity, nomatter whether the end mill is installed directly in a collet or used in an MT2 holder. So I got the idea of making my own end mill holders that would screw onto the spindle.

 

[JPMacG]

In order to minimize runout I bored the holders in situ on the MFC, then reamed them to final diameter on the lathe.

 

[JPMacG]

Each holder is about 2.3" long - a nice compromise between collets, which tend to be too short for most milling operations and an end mill holder, which tends to be too long.

 

[Ulma Doctor]

Nice work, they are sure to serve you very well!
the most accurate way to bore the holders is on the machine!!! nice touch

 

[VSAncona]

Beautiful job! I really like your design. I just made an end mill holder for my MFC based on the original Atlas design and I agree with you that they can be too long for some situations. Here is a video of my efforts:

 

[wa5cab]

The complaint about the Atlas 2MT holder with the four sleeve reducers is that it is too short.

All of the standard commercial holders that I have (and that I do not recall the source of) are about the same effective length as the custom made set or maybe are a little shorter but every %$#@ one of them is the Tanged instead of Draw Bar type. As I have said numerous times before, never ever use a milling cutter holder loaded with anything other than a drill bit that is not secured in the spindle with a Draw Bar.

 

[VSAncona]

Atlas made two different lengths of 2MT holders. The short one is number M6-945 (top one in photo) and was sold with a draw bar for use with the 6” Atlas lathe. The longer holder, number M1-577 (middle one in photo) was sold specifically for the milling machine and uses the same draw bar as the horizontal cutter arbors. In addition to the extended reach needed for the horizontal mill, it‘s also long enough to hold double-ended end mills. The holder at the bottom of the photo is a Polish-made Bison brand 2MT holder, also with a threaded end for a draw bar. It’s entirely too large for the tiny Atlas.

 

[VSAncona]

Where did you get boring bar you used for the small dia, holders? I wanted to bore mine, but didn‘t have a small enough boring bar.

 

[JPMacG]

It was in a set of boring bars from Little Machine Shop. https://littlemachineshop.com/products/product_view.php?ProductID=2682&category=

The bar is not as rigid as I would like. I took lots of spring passes and it was difficult to control the diameter to better than a few mils. I used a reamer to get the final diameter - back on the lathe.

 

[JPMacG]

Your YouTube video is excellent. Thank you for publishing it. I just subscribed to your channel.