If the cup goes in easily to the half-way point, it should be easy at this point to SEE whether the cup is tilted in the bore of the bb (i.e. cross-threaded). I've seen French-threaded PX10 cups easily go in at least that far and actually be noticeably cross-threaded, at which point I back it out and tap the cup level with a hammer (forcibly restoring) before screwing it in again.
If it's all lubed up, I'd put some torque into it and note the way it tightens up, either linearly or with a sharp up-ramping of torque indicating more than a bit of local thread interference. I would definitely use "big enough" tools to assure that even greater loosening power is available at such point that you may decide to back it out and perhaps try again. Also, as a test, I would mesh the threads of the two cups together as a pitch check and compare thread diameters with caliper (or adjustable wrench in a pinch).
I believe that the rolling diameter of the ball tracks of most bb's using 1/4" balls are all the same, so spindles/cups should interchange where thick/thin cup discrepancies are tolerable as far as chainline and lockring fitment are concerned.
David Snyder Auburn, CA usa
Keith Kessel wrote:
>
> When trying to install the Campag. permanent English
> threaded cup, it got
> hard and started trying to crossthread about half way in.