11.5 Threads Per Inch Possible On Pm1236?

[Lynrob]

I have a PM1236 lathe and I need to make a part with 11.5 threads per inch. 11.5 is not listed in the threading chart on the side of the lathe but I was wondering if there is a way to do it? Also, the change gears on my lathe are so tight that I need to use a gear puller to get them off. Is that normal?

 

[roadie33]

If it will do 2.2 in metric, that might work if it's not too long of a thread. Test it out on a piece of scrap and see if it matches.

 

[springer]

Not sure about the thread pitch question, but my change gears are extremely hard to get on and off as well. I don't need a gear puller, but still hard. I took them all off, cleaned them dry and lubed them as well as the shafts they go on and that helped a bunch.

 

[blaser.306]

Is what you are looking for a "measured thread" or a listed one ( cannot go to my Machinery's handbook) to see if it is noted there? Perhaps it is as simple as a metric thread

 

[Lynrob]

I hadn't thought of trying a close metric thread... I'll check into that. I have also removed, cleaned and lubed my gears and shafts without any noticeable improvement. Luckily I haven't had to change the gears too often.

 

[T Bredehoft]

Yeah, metric 2.2 might work. It comes out to 2.208. That's well under 1% error, turns out to be .oo4% ± one decimal place.

 

[RJSakowski]

Yeah, metric 2.2 might work. It comes out to 2.208. That's well under 1% error, turns out to be .oo4% ± one decimal place.

Tom,

It's actually .4% but with a short enough thread engagement and perhaps a slightly undersized thread, it should work.

Bob

 

[Lynrob]

Thanks everyone! I'll give it a try this weekend.

 

[lpeedin]

Are you working on a garden hose fitting? I just made a water balloon filler adapter for my kids and I believe that was what the actual garden hose thread is. Since I only need a few threads, I went with 12 pitch since that was the closes my PM1127VF-LB would do.

 

[Andre]

Are you working on a garden hose fitting? I just made a water balloon filler adapter for my kids and I believe that was what the actual garden hose thread is. Since I only need a few threads, I went with 12 pitch since that was the closes my PM1127VF-LB would do.

I believe garden hoses and pop bottles are 11.5 TPI. So are M1 barrels strangely enough.