Trapezoidal 22x8 thread need help !!!

[Fullmetaleng]

I am new at work and also new to manufacturing and need to cut internal/external trapezoidal thread 22x8-H7 (D 22mm Pitch 8 mm) on equivalent of 4140 steel and cant find right tool for the job. Could you please suggest either manufacturer or where to look for it. Thank you in advance!

[Milland]

I've no idea if this is the correct series of thread form you need, but you can try contacting your country's ISCAR representatives to see if it is, or if they have the right insert in a different series.

https://www.iscar.com/eCatalog/Famil...&GFSTYP=M&fr=1

[Fullmetaleng]

Thanks, I also found this tool but when I choose one with 8 mm pitch related tool holder minimum bore diameter is 40 mm and I need 22mm

[Milland]

Still worth contacting ISCAR, I believe they can make custom inserts if required.

[Limy Sami]

My thoughts.

22 x 8 is one hell of a pitch, the helix angle will play havoc with the internal tool, .......not to mention the <>4mm depth of thread, which means the minor dia will be <>14mm ............to get a tool that depth of thread in? .................which would be about a 9mm shank to allow for the projection, .......................... .all in all a nightmare

Is it not possible to use a 2 start 22 x 4

FYI Calculation of Thread Lead Angle | MITSUBISHI MATERIALS CORPORATION

[Fullmetaleng]

manufacturing team tried to make part with self made tool and had exactly those problems since shank was 9 mm it could not take the load and was breaking. We suggested design team to change thread to 2 start 22x4 but they declined saying "since thread like this exists it is possible to make it so its your problem". So in the end its my problem.

[Limy Sami]

Tell them to find the tooling!

[Peter from Holland]

Have a special tool made out of a solid piece of carbide perhaps
How deep would be interesting
Sinker EDM the TR22x8 is also possible I think

Peter

[Fullmetaleng]

I will try custom made tool, its a 60mm blind hole

[Peter from Holland]

Let us know the outcome please

Peter

[jz79]

both pieces high strength steel, "non standard" pitch, blind nut on top of that...

I'd suggest looking for another place to work if you want to keep your sanity

22x5 seems to be more or less standard, taps available, not that they'd work for a blind hole, but anyway, and ready made rods and nuts also seem to be available

[JS]

[]

[Limy Sami]

I will try custom made tool, its a 60mm blind hole

YIKES! 60 mm long ''nut'', and blind, you must wrestle alligators for relaxation

Be sure to tell design just how much the special tool costs, .............and IMHO unless you are very lucky, you are going to break a few tools.

P.S. Double the price if it's too cheap (not that you heard that from me)