Tool holder holding a "T" cut off blade

The 250-107 parting blade holder is touted as a "universal" blade holder, and is claimed to be compatible with both P type and tapered cutoff blades. For instance: this one. Most of the images I found online weren't detailed enough to see how it can accommodate P (or "T" profile) blades. Maybe there's a trick to installing the blades.
 
 
The blade leans to the side a bit and I have no idea how to make it stand straight up.

For the last 20 years I've had only one vise on my mill. I had ordered it with a swivel base and, in all those years, I have never used the swivel. Recently, I decided to buy an upgrade vise (GMT, 4") and ordered it without a swivel base. Couldn't justify it based on my long history of non-use.

The very next day I decided to try a P style cut off tool that has been in my toolbox for about as long. (I've always ground my own cut-off tools.) Mounted the blade, saw the issue you describe and immediately put the tool holder in my 20 year old vise and used the stupid swivel base for the first time ever!

The irony was hilarious and I was smiling and chuckling the entire time I cut the groove in that toolholder.

MetaKey
 
I took off the swivel base off of my vise. I can't adjust the angle with just the vise on the mill table, so I gotta put the swivel base back on.

The tool holder is made of some pretty hardened steel. I used a 5/16" HSS endmill and I can't cut it correctly. The tool holder steel is becoming "gummy."
 
I have used P type and tapered blades in the same non relieved Aloris holders for probably over 40 years, I've thought about relieving the holder, but it seems to work fine as is. I use HSS parting tools for most work, and reserve carbide for stainless and deep cut off and grooving roughouts.
That HSS tool shown has probably at least 4 times too much front clearance, which drastically weakens the tool and would cause it to wear off at the point, likely burning off and possibly causing hard spots, as stated above, 7 degrees more or less should do the job. Radical grinding showing burning is likely to cause fine cracking at the cutting edge, "they" say.
 
Yeah, the tool holder was a little tough. Not like 4130 or stainless tho.

I used a four flute 3/16” HSS end mill and the DOC was .030” which was all that was needed to clear the blade.

290530

I was running at least 1000 RPM. Maybe more. Mill goes up to 3250. Didn’t think about it much so I don’t recall.

MetaKey
 
Too fast for hard, unless carbide cutter.

Wasn’t hard, can cut it with a file. Cut nicely with that 3/16” HSS cutter.

It’s an import tool holder so I’d have to designate it as mystery metal. ;-)

MetaKey
 
Wasn’t hard, can cut it with a file. Cut nicely with that 3/16” HSS cutter.

It’s an import tool holder so I’d have to designate it as mystery metal. ;-)

MetaKey

Yep, I've milled & turned China holders. They're not that hard. China hardened is not the same as USA hardened. :big grin:
 
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