Quick change tool post compatibility

[Thriller]

For my craftex CX706 10 x 22 lathe Purchased a quick change to a post from KMS Tools. I think the brand was Magnum. They have numbers on the tools holders like 250-102. When searching for more tool holders I was looking on the Shars site and they had dimensions to their extra tool holders. Those dimensions were substantially different than mine even though they had the same part number.I take it these are not all compatible? So how do I know that I’m buying the right tooling to fit my quick change post?

On a sidenote I have a 250-102 and a 250-101 that look identical but have different part numbers on them. Does that seem odd as well.

 

[matthewsx]

In my experience they print all kinds on numbers on these tool holders. Assuming yours is an AXA any AXA tool holder should work with your tool post, at least that's my understanding.

Cheers,

John

 

[Ed ke6bnl]

102 is probably the same as the 102 BUT the tool holding opening may be larger

 

[kd4gij]

250-101 should be flat on the bottom of the tool slot. 250-102 should have a half with v grove in the bottom to hold round tools as well as square tools.

 

[RJSakowski]

For my craftex CX706 10 x 22 lathe Purchased a quick change to a post from KMS Tools. I think the brand was Magnum. They have numbers on the tools holders like 250-102. When searching for more tool holders I was looking on the Shars site and they had dimensions to their extra tool holders. Those dimensions were substantially different than mine even though they had the same part number.I take it these are not all compatible? So how do I know that I’m buying the right tooling to fit my quick change post?

On a sidenote I have a 250-102 and a 250-101 that look identical but have different part numbers on them. Does that seem odd as well.

The 250-102 has a vee groove down the center of the bottom face to hold a boring bar. It also holds the square tools.

Dimensions will vary slightly from manufacturer to manufacturer.

 

[pontiac428]

The dimensions given on Shars for the 250-101/102 may be bad, hence the mismatch. Any 250 series tool holder should fit your AXA post. I've ordered from multiple suppliers (sometimes there are inexplicable "shortages") without any issues, and the dovetail design is tolerant of certain dimensional specs being out. As long as it places the tool in the same location repeatably, it will work.

 

[Thriller]

OK great. So this is what I have learned so far. The 250-102 is different because it has the groove. I found you can also get a 250-102xl that will take a 5/8" instead of a 1/2". Now why would anyone buy a 250-101 if they had the option to buy the 250-102?

Next question. Why do some tools have a carbide shim that goes under the actual carbide insert?

 

[mikey]

OK great. So this is what I have learned so far. The 250-102 is different because it has the groove. I found you can also get a 250-102xl that will take a 5/8" instead of a 1/2". Now why would anyone buy a 250-101 if they had the option to buy the 250-102?

Next question. Why do some tools have a carbide shim that goes under the actual carbide insert?

The answer is that you probably cannot get the tip of a 5/8" tool on center even if you have the XL holder. You may not even be able to get a 1/2" tool on center on your lathe. I have an 11" lathe that requires me to grind a 1/2" tool to get it on center so going bigger makes no sense. On top of that, my lathe is not rigid or powerful enough to take advantage of the bigger tooling.

The shim is called an anvil. Quite often, especially on the more expensive tool holders, they use a carbide shim to handle the wear that a chip breaker insert imparts to the insert holder. If not for the anvil, the chip breaker will wear into the steel of the tool holder and there goes your geometry. Plus, if you ever crash the tip of the tool, it is cheaper to replace the insert and anvil than it is to replace an expensive tool holder.

 

[Thriller]

Well that is exactly why I came here. To get the knowledge that I do not have. Thank you very much. I do run a couple different types of carbide insert tools and they are both 1/2. I am able to get to the center with those ones, but you are right about the height. I don't have much more room to drop down on my quick change tool post. Probl b only a couple of threads left on the adjuster nut with the 1/2" installed.

The answer is that you probably cannot get the tip of a 5/8" tool on center even if you have the XL holder. You may not even be able to get a 1/2" tool on center on your lathe. I have an 11" lathe that requires me to grind a 1/2" tool to get it on center so going bigger makes no sense. On top of that, my lathe is not rigid or powerful enough to take advantage of the bigger tooling.

The shim is called an anvil. Quite often, especially on the more expensive tool holders, they use a carbide shim to handle the wear that a chip breaker insert imparts to the insert holder. If not for the anvil, the chip breaker will wear into the steel of the tool holder and there goes your geometry. Plus, if you ever crash the tip of the tool, it is cheaper to replace the insert and anvil than it is to replace an expensive tool holder.

 

[mikey]

I own both 3/8" and 1/2" inserted carbide tools (Iscar and Seco tool holders) and I do not see any difference in tool performance between them, and I have 2HP and a very rigid lathe for its size. The smaller tools are cheaper, the inserts are cheaper but performance is the same so I usually reach for the smaller tool. Your call, though, so go with what you think best.