DNMG style insert to cut a 55 degree Whitworth thread?

[judavis126]

I plan to rebarrel my large ring Mauser that has a 1.1 x 12tpi whitworth thread. I can order a 55 degree threading insert but was curious if there is any reason I can not use a neutral tool with a DNMG-431 insert. I realize I will have to grind the side of the insert for clearance. The two possible issues I can think of is the .0156 radius on this DNMG insert. If I am looking at the correct whitworth thread form, it calls for a .011 radius in the root of the thread. The other possible issue would be the insert clearing the shoulder on the barrel that I am threading up to. I plan to cut a .1 wide thread relief. Has anyone tried this? Thanks

 

[MilGunsmith]

If you are going to spend the time to grind an insert, just grind a proper 55 deg HSS tool and thread it.

 

[judavis126]

Thanks for the recommendation but I don't have the proper equipment available to me to accurately grind HSS. Grinding clearance on the backside of a carbide insert does not require any real accuracy.

 

[GenePoole]

Thanks for the recommendation but I don't have the proper equipment available to me to accurately grind HSS. Grinding clearance on the backside of a carbide insert does not require any real accuracy.

I don't generally try to discourage innovative ways to get around problems, but this doesn't really qualify in my opinion. For little more than the price of a 12-pack you can probably get the proper wheel you need for your grinder.

 

[judavis126]

I was just trying to ask if one could use a 55 degree turning insert such as a DNMG-431 to cut that particular mentioned 55 degree thread. I realize there are many ways to skin this cat but it was just suppose to be a simple question with hopes someone has tried it and it either worked or it didn't work. I will spend the $25 on the proper threading insert before I mess with buying a grinding wheel and some HSS and trying to grind it.

 

[GenePoole]

As a followup, I'm surprised at the availability of 55° inserts. Apparently it's still a pretty popular thread:

AG55 thread inserts in Manufacturing and Metalworking Equipment | eBay

 

[judavis126]

To conclude this, just talked to my local tooling supply. Iscar 16er ag55 in stock for $9.43. Going to pick one up this afternoon and be done with this. I had also found some on eBay, Amazon and MSC. Locally being the best price though.

 

[Illinoyance]

Get a 55* fishtail gauge for a couple bucks. Grind a tool from HSS. If you are not capable of that you should probably give up machining.

 

[judavis126]

Your an ass. It was a simple question asking if a particular tool would work for a particular operation. That's it. Grinding HSS was never in the question. Quit telling me to go buy all this crap to grind HHS. If you would have read the reply right before yours you would have noticed the issue was solved.

 

[GGaskill]

Your[sic] an ass.

He may be (or may not be) but that kind of content is out of line.

Thread locked.