long case clock

Hi, wheel posts are threaded 3BA, so the spares catalogue tells me

The tapping hole for 3ba is 29 or 3.4mm, and these will not go through the hole in the plate I am looking at. I have tried to determine the thread from the range of taps I have , but no success. Any suggestions as to what may have been used.

Thanks, Lynne

Lynne,

What clock & what catalogue ?

MichaelG.

...........Michael beat me to it!........

If you want to know what thread then shave down a spill of softwood and (carefully) screw it into the threaded hole then compare with a thread guage.

"wheel posts" are usually called 'arbours' but they are not usually threaded.......

Hi Lynne,

If you want a pukka traditional job the frame posts are secured with tapered pins, not threaded and with nuts added.

Cheers,

Julian

Hello Lynne,

​Please forgive me for gate crashing your post, but I have sent a PM to Bob Stevenson and wanted to catch his eye while this is still current.

Regards
​Brian

.....Hello Brian,...I have sent you an email just a minute ago!

Thanks for the responses.

Michael & Bob. 8 day longcase, english movement, well, the name on the brass face is Geo. Booth, Manchester. Hasn't ticked for 40 years that I know of. Weights, one cast iron, could be original, the other, pretty poor lead casting. Also missing the gathering pallet, which will be a challenge. The hands need attention, minute hand broken, but I have the pieces. There is more.

Catalogue. Meadows & Passmore. They describe them as Rack & minute wheel studs. Cousins describe them as Rack & lifting piece posts/studs. The 22mm length is insufficient, I need 25mm, so I will have to do a repair. Minute post is sound, Maj. thread dia. is 3.43mm, hole dia. 3mm. tread pitch using BA guage would appear to be 3BA.

So, what to do? drill 3.4 and tap 3BA, or try to match the original form. Regards Lynne

Thanks, Lynne

Here's the Rack Stud, for everyone's reference **LINK**

http://www.m-p.co.uk/muk/parts/chap03/rack-stud-1459000315.htm

Proper 'conservation' would mean modifying the new component [or making from scratch] to fit the existing tapped hole ... but only you can decide whether that is appropriate.

MichaelG.