Drawing a blank in the hardware isle ?

Drawing a blank in the hardware isle ?

B
B

October 12th, 2008, 9:05 pm #1

what screw size has the same pitch and diameter of 1/8" NPT with out the taper in it.


I need to take up some space in an long threaded passage.
Quote
Share

y0da900
y0da900

October 12th, 2008, 10:52 pm #2

National Pipe Straight threads, no taper. You most likely won't find one in a brick & mortar hardware store.

http://www.wttool.com/product-exec/prod ... _WT_Import_
Quote
Share

Doc Nickel
Doc Nickel

October 13th, 2008, 7:52 am #3

what screw size has the same pitch and diameter of 1/8" NPT with out the taper in it.


I need to take up some space in an long threaded passage.
Yoda's got it. You'll need to find a National Pipe Straight plug or fitting. 1/8" NPT is 27 threads per inch- you're not going to find any other bolt, plug, setscrew or fitting that'll fit it.

Doc.
Quote
Share

B
B

October 13th, 2008, 10:04 pm #4

I have been screwed twice by flaky owners on 2 9" south bends.
Quote
Share

Russ Kepler
Russ Kepler

October 13th, 2008, 11:12 pm #5

I don't think the 9" SB would do 27tpi, not with the quick change gearbox, anyway. 27 is sort of weird in the inch pattern, doesn't have a double or half like most other threads.
Quote
Share

Doc Nickel
Doc Nickel

October 14th, 2008, 12:34 am #6

I'm not sure about the Southbends, but my Sheldon lathe can go quite a few oddball threads- 5-1/2 TPI, 5-3/4, 6-1/2, 13-1/2 and 27 TPI, among several others. I was reasonably certain my Logan could too, but apparently not. It can do a couple of the "common" oddballs, like 11-1/2, but not 27 TPI.

Doc.
Quote
Share

B
B

October 14th, 2008, 1:39 am #7

Quote
Share

Russ Kepler
Russ Kepler

October 14th, 2008, 2:42 am #8

Sure, with change gears pretty much anything can be cut - that's why I said "with the quick change". Heck, I've even cut module threads on my lathe and some really weird shit for an injection mold, had to cut the thread a percent large to account for shrinkage.

But 27 tpi isn't common on quick change gearboxen because none of the multiples are used - 54 tpi? 13 1/2 tpi? 11 1/2 is semi-useful because 56 tpi is used (well, by some stuff, I've done a fair bit of 5/16-56).
Quote
Share