Help Me Pick Out Tool Holders

[davidpbest]

You should be looking at a trigon insert toolholder for roughing. Like this.

For finishing, I would recommend an 80° rhombus CCMT style insert toolholder. Like this.

The Aloris tool holder you have, and especially the inserts you used to make the dead centers is not designed for that type of work.

 

[mattthemuppet2]

learning how to use a lathe and mill is a very steep learning curve and to add to that you have a large and powerful lathe, which adds an extra dimension. I'm sure you don't like import stuff (other than your lathe) but I'd get a set of basic trigon or CCMT turning tools from Carbide Depot or the like and use those until you have a better feel for what you need. That way if you do break anything then you're not out much.

 

[erikmannie]

Update:

I called Aloris today & talked to the tech guy. He apologized that he was unavailable yesterday, and he told me to send the failed tool holder back for inspection & possible warranty replacement. This is the tool holder that is in the garbage, so I’m glad I didn’t empty the garbage yet.

I still don’t like the Double Lock/Sure Lock designs, at least for heavy cuts. I will choose a more sturdy tool holder (where the insert either screws in directly or has a big locking lever over it).

 

[erikmannie]

You should be looking at a trigon insert toolholder for roughing. Like this.

For finishing, I would recommend an 80° rhombus CCMT style insert toolholder. Like this.

The Aloris tool holder you have, and especially the inserts you used to make the dead centers is not designed for that type of work.

I called carbidedepot.com, & I emailed the tech guy William your 2 links above. He came up with a Kennemetal tool holder which is hopefully equivalent to that Seco that you linked to:

(1) MWLNR123B, Kennametal PN 1096362

https://www.mscdirect.com/product/details/64922826

picture:



(2) MWLNL123B, Kennametal PN 1096357

https://www.mscdirect.com/product/details/04419834

picture (shows a RH):



(3) SCLCR123, Kennametal PN 1094485

https://www.mscdirect.com/product/details/64922230

picture:



(4) SCLCL123, Kennametal PN 1094486

https://www.mscdirect.com/product/details/04760393

picture (shows a RH):

 

[erikmannie]

For inserts, the carbidedepot.com tech guy recommended the following for machining carbon and alloy steels:



and

 

[davidpbest]

Yes, those are the Kennametal equivalents. Those should serve you well. Make sure you get inserts suitable for your materials. The CCMT versions should have a small nose radius for finishing operations.

 

[erikmannie]

Yes, those are the Kennametal equivalents. Those should serve you well. Make sure you get inserts suitable for your materials. The CCMT versions should have a small nose radius for finishing operations.

Would you consider a nose radius of .016” to be small? It sounds “medium” to me.

After I told him what I do in the shop, the tech guy was setting me up with inserts for carbon and alloy steels only.

 

[erikmannie]

I followed up with the tech guy & he says that for inserts with a 3/8” inscribed circle radius, 90% of his customers are choosing a .016” nose radius. I’m going to go with that for now.

 

[davidpbest]

The rule of thumb for finishing cuts is the depth of cut must be at least half the nose radius of the insert. So you can answer your own question. If you plan to take finishing cuts of 0.008" or more, they are fine. If you try to remove 0.002" with those, the surface finish is likely to be total crap because the insert isn't consistently engaging in the material. I use that same insert in my shop on lots of varieties of steel, but to hit tight tolerances, I use the balanced method I talked about earlier in this thread with a link to a video on the technique. I would never try to hit tight tolerance by creeping up on it with light skim passes.

 

[erikmannie]

The rule of thumb for finishing cuts is the depth of cut must be at least half the nose radius of the insert. So you can answer your own question. If you plan to take finishing cuts of 0.008" or more, they are fine. If you try to remove 0.002" with those, the surface finish is likely to be total crap because the insert isn't consistently engaging in the material. I use that same insert in my shop on lots of varieties of steel, but to hit tight tolerances, I use the balanced method I talked about earlier in this thread with a link to a video on the technique. I would never try to hit tight tolerance by creeping up on it with light skim passes.

Yes, I came to fully understand the above on my most recent project, with thanks to the Hobby Machine Forum crew.

I sometimes bring in HSS tool bits if I undershoot my target by less than half of the insert nose radius, thereby losing the surface finish achieved with the carbide.