Member postings for keith hodgson

Thanks for all the responses folks - I'm beginning to think the thread is 10mm x 0.8 pitch, having tried a metric pitch guage now as well as an imperial one, as I can't see the difference over about 10 threads.

Frustratingly, I could retain all the original fittings I have, which are double ended, one end threading into the crankcase/oil tank/oil pump etc, the other end to a compression fitting of a missing oil line. However all the fittings I need are the compression nuts, so I'd have to screwcut these threads internally into a blind hole - not my favourite pastime!

I may remake the double ended male components 10mm x 0.8 pitch one side, and 26 tpi cycle the other, and make all the compression nuts 26 Cycle also. Would be happier using a tap up the nuts.

I specifically didn't include much motorbike detail as I thought the post may get moved, and the thread i/d was the important issue, however if I can remember how to attach a photo I'll put one up. I do have an RE with the Motosacoche engine (1912), but the bike in question is from 1915 and has Enfield's own in house engine with a totally different oiling system to the Swiss engined bike (dry sump recirc, rather than total loss - way ahead of it's time). Notice the GLASS oil tank.

Edited By keith hodgson on 24/10/2022 16:25:46

Edited By keith hodgson on 24/10/2022 16:26:36

I have a couple of Royal Enfield motorcycles, each in excess of 100 years old. In the course of the restorations (running concurrently), I need to make some compression fittings male and female for oil circulation lines. The thread count of the existing fittings is definitely 32 tpi, but the diameter is odd at 0.392" over the crest of the threads - suspiciously close to 10mm.

Can anyone help as to whether this is from a recognised thread form/classification that I am unaware of, or maybe they're just a special fine thread that the manufacturers came up with. This is the only size/diameter other than standard Cycle thread in use on the bikes.

Thanks for all the responses guys.

I think that on balance, I will go with the reasonable steel/unhardened approach. My application is not highly stressed (as compared with a hi comp engine). Photo of the bike accompanying - all of 2.75 horse power - yes that's 2 point 75, not 275. It's a 1927 Ladies model Royal Enfield of 225cc (2 stroke). I have only used my vertical mill in the upright mode, but understand it is possible to swivel by 45 (not sure if I can get 90 deg, to turn the spindle horizontal). If I can, then maybe I can bolt the kickstart quadrant to the blank and carefully work from there.

The teeth profile is 10 DP, and from a quick scan on ebay, I can see something referred to as 'pressure angle' comes into play (I thought these were straight cut, so angles wouldn't be an issue). Can anyone enlighten me? I see (if applicable) there are 2 angles, 14.5 and 20 degrees, the former being used in 'olden days', and probably applicable to my situation.

If I find an 'involute'? cutter they seem to be number of teeth related, so that would refer to the full circumference (in my case 63/64 teeth)?

Hi folks, first post, but been looking in for a few years.

I need to make a kickstart for a vintage motorcycle as per the photo (haven't put this in vehicle resto section as it's more about metals and processes than vehicles).

I'll probably make it in 3 or 4 parts and weld together. Concerned about the teeth being hard/tough enough. Maybe case hardening by kasenit? Certainly don't want to go for any professional heat treatment if at all possible. I have oxy acetylene, if I heat after the teeth are cut, does the hardening require a length of time at temp before immersion in the powder, and a length of time soaking?

I thought EN8 for all parts.

Next, I only have a vertical mill, and don't have a dividing head, would anyone be interested in milling the teeth for me (might want 2 doing)? 10DP, radius to o/d of teeth approx 83mm.