Myford spindle information

[retailer]

I may be wrong but I'm sure I recall seeing somewhere that the Myford spindle thread is Admiralty not Whitworth. This web site is a good reference site for thread info.

http://pages.cs.wisc.edu/~bolo/workshop/thread.html

 

[BaronJ]

Hi Guys,

Myford spindle nose details.

 

[goldstar31]

I may be wrong but I'm sure I recall seeing somewhere that the Myford spindle thread is Admiralty not Whitworth. This web site is a good reference site for thread info.

Somewhat tenuously and timidly, May I disagree?

Drummond Brothers- which was taken over by Myford had 'an Admiralty pattern' lathe.
Whether Myford actually made these lathes for sale to the lords of Admiralty is not known.

The 'noses' on the two lathes are very different.

 

[RonW]

Thanks Goldstar31. Better late than never. As reported earlier I now seem to have "mastered" making these back-plates etc having now produced at least four variants for different projects. Thanks for the help.
RonW

 

[Neil Lickfold]

I realise thus is an old post, but measuring my S7 spindle, the taper is very close to 12deg,25 mins. Or 12.4166 deg included angle. I recut the taper of the spindle and used the same taper rate for the new bronze bush. They scrap the inside for oil retension in the taper. Fit it to the bush once the bush had been pressed into place.

 

[redhunter350]

Thanks Goldstar31. Better late than never. As reported earlier I now seem to have "mastered" making these back-plates etc having now produced at least four variants for different projects. Thanks for the help.
RonW

Hi RonW a bit late to the party - was looking for something else ! However I see BaronJ has posted the correct spindle dimensions but here is a plug gage I made for checking the progress when making tooling, maybe it will be useful -- if you needed different wire sizes let me know.
I see someone also mentioned the importance of the register diameter -- this is THE most important dimension and in the absence of a good bore micrometer I would make a plug gauge for this as well.
Cheers John

 

[BrianC]

Thanks Hopper. I guess my biggest question is trying to decide what the major and root diameters will be. This is an oddball size in that its 1 1/8" diameter but 12 TPI so charts of threads don't really help. If I use the outer diameter of the spindle and the internal diameter of the chuck or face-plate is that going to be "close enough" for a good fit? Having already turned part of the blank I'm unsure as to how to proceed without screwing the part. Excuse the pun. I'll consult the library some more and see what the books mentioned have to say.

1 1/8 x 12 tpi whitworth form is an Admiralty specification

 

[Neil Lickfold]

I realise its an older thread, but with the spindle taper, mine is 12deg,25mins. Or 12.4166deg included angle.
For the Nose thread, I used a 12TPI Whitworth full form inserts for the internal threads . Made a dummy spindle nose , replicating the reference diameter of my spindle and with thread wires replicated the thread diameter. Again I got a 12TPI Whitworth full form threading insert. Mine is about 0.02mm on diameter smaller than the Nominal 12 tpi pitch diameter.
I recut the spindle taper and have made a new LG2 tapered bush. It will need scraping after it's installed mainly for the hydrostatic oil effect for its lubrication. An interesting subjuct on its own.