Upper and Lower lines won't thread

[jaydett]

Hey all, I picked up upper and lower brake hoses for my 73 from xs650direct and I am finding that they will not thread much. I can get the threads started but after about a turn and a half they stop. Am I missing something here or would there just be a bad set of threads causing a cross thread?

 

[5twins]

Sounds like bad threads or the wrong thread pitch. Compare the new part to the old one. Lay the new thread on top of the old thread and see if they match up, mesh together perfectly. XS Direct is a division of Mikes, who is not noted for quality control. Check out this bottom oil pipe fitting my buddy got (on the left). No way that was threading in, lol .....

 

[jaydett]

Wow that's bad! I will take a look and compare the two.
Thanks

 

[fredintoon]

Hi 5twins,
HTF could they make that wiggly thread anyway?
I can understand them making the part with a wrong pitch, diameter or threadform but varying the thread pitch like that has to take very special tooling.
And jaydett, by all means see if you can get your money back but even if you have to kiss the money goodbye, go get a stainless brake line from a good manufacturer.

 

[TwoManyXS1Bs]

...HTF could they make that wiggly thread anyway?

I've been staring at that pic for over 10 minutes, tryin' to post-mortem the thing. Fred, you know about machine setups. Does this scenario make sense?

Most of the machining is done, the larger threaded portion is facing outboard of the chuck.
The threads are cut.
The oil restriction hole is drilled.
The turret is spun to the counterbore bit.
Maybe a turret misalignment occurs.
The turret's bit crashes into the workpiece, off-center, crushing one side and deforming it.
The operator realigns (or replaces) the counterbore bit, correct counterbore cut.
Facing tool squares the end.
Result: everything looks ok, except for the 'wiggly' threads...