Twin start threads

[conetip]

Does or has, anyone made pins with twin start threads, like a 5/16-18 with a 9 tpi lead?
I did a search, but nothing came up, not say it has not been done before.
Just curious,
Neil

 

[RBC]

Does or has, anyone made pins with twin start threads, like a 5/18-18 with a 9 tpi lead?
I did a search, but nothing came up, not say it has not been done before.
Just curious,
Neil

Neil

Years back, Huebler cues made a jump break cue with exactly that screw in the center section. It was an 18 TPI 2 start screw so it had a pitch .111" as opposed to .0556".

The interesting thing about it was that it had little marks or spots on both sides of the joint and you had to line them up before you screwed it together. If you didn't, the union would be lopsided and not centered. Of course, that meant that the screw was not in the center, which was pretty common back then. Many of the cues made 20 years ago had the screws put in them before all the turning was done so if the cue moved any while it was being tapered the screws were no longer in the center. You couldn't even swap shafts back then without fear that the joints would not line up very close at all. The worst part was that if you needed to face the joint, like say if it was dropped and damaged, the shaft and butt would no longer line up.


Royce

 

[whammo57]

Jabs

why make JABS

just another bastard screw???? for what purpose????

Kim

 

[JoeyInCali]

why make JABS

just another bastard screw???? for what purpose????

Kim

5/8 is kinda big for a joint screw.

 

[conetip]

Joey, ment to have typed 5/16 not 5/18 , I was thinking about using it for ferrules.
The idea is, that it will self align when used as a tennon threader , instead of pushing off to one side a very small amount like the current single start threaders do. On normal ferrules it is not really a problem as they are usually turned down and faced anyway. Those with live tooling capability are not effected with single start threaded parts.
Neil

 

[JoeyInCali]

Joey, ment to have typed 5/16 not 5/18 , I was thinking about using it for ferrules.
The idea is, that it will self align when used as a tenon threader , instead of pushing off to one side a very small amount like the current single start threaders do. On normal ferrules it is not really a problem as they are usually turned down and faced anyway. Those with live tooling capability are not effected with single start threaded parts.
Neil

Ah.
I'm liking the bastard .350 by 18 TPI these days for ferrules.
.350 by 3/16 alignment shoulder at the bottom.