Thread pich on Quill/Nose piece J2 head

[hnn74]

Thread pitch on Quill/Nose piece J2 head

Does anybody know (for sure) what thread is used for the J2 head quill and nose piece?

Just bought a bp with stuck quill and missing feed handle… After tearing down head and tapping out the quill I can conclude some previous owner (possibly gorilla) has reused a nose piece with damaged threads and forced it into the poor quill using a pipe wrench with enough force to cause plastic deformation, leaving it bell-mouthed. I had to use violent metods to get the nose piece off leaving that part totally destroyed. I have ordered a new nose piece from H&W in the states but would like to use the waiting time to do my best to save the threads in the quill. My plan is to chase them on my lathe but then i need to know the correct thread pitch. My guess is that it is a 20 tpi thread but it is distorted enough to make me uncertain…

I have spent several evenings stoning the quill by hand using blue to try and get it to retract all the way in the housing. I am almost there but I start losing the chrome at the very bottom of the quill… I wonder why people need to abuse nice old machinery like this…

//Henrik from Sweden

 

[hnn74]

Guess I will answer my own question… Nose piece finally arrived today together with some other goodies from H&W. Thread seems to be Withworth 55 degrees 20 tpi (kind of odd....) I managed to chase the thread on my old Bolinder Munktell C40 lathe. I now have a pretty sloppy fit even though i didnt take any extra depth but the nose piece threads easily all the way by hand so I call it good enough. Guess the nose piece just holds the spindle assy in place so will just snug it and drill a recess for the set screw to avoid future stripping of the thread. Started taking the machine apart while waiting for parts for the head and ended up tearing the whole thing down so now she will get a fresh coat of paint, rebuilt head and new spindle bearings! //Henrik