I think my dad had one of these tools for making threaded. wood by hand. You can make accurate threads by hand if you make a jig. The key is that you but-joint the wood dowel to a threaded metal rod with threads of the desired pitch and put a nut on the metal rod. The nut and your tool are fixed to the bench with clamps. Of course you need to make about 100 passes to cut the threads.
Even 200 years ago I doubt anyone made these my hand and eye, you need some kind of jig.
I think maybe you¡¯d need to try it by hand to see how the tool work and what angle is best
There is a person on another machine tool ist who is set up to mass produce these wood clamps using maple dowels and a CNC lathe
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On Jan 15, 2024, at 11:39?PM, DAVID WILLIAMS via groups.io <d.i.williams@...> wrote:
Dear All,
I realise this is both part Mini lathe and part wood lathe. But to me the metal lathe part is more important. Hence my question to you all.
I have a couple of these old wooden clamps - probably antique. They are just like the metalwork ones we use, but much much larger. One has a severely damaged (external) threads.
I would like to try(?) and cut the replacement long wooden thread on my 7 x 12. So, I bought a second hand thread chaser on eBay. It¡¯s 6 TPI and according to the chart on the Little Machine Shop site - the gear set up is no problem on my imperial lathe.
[JFI it¡¯s Real Bull model purchased from Chester Machines (in the UK) some 20+ years ago. If that¡¯s at all relevant?]
The thread chaser cuts multiple threads at the same time and the tool (normally hand held I understand) needs to be held at ~ 90 degrees to the thread, unlike the usual angle for cutting one side of a metal thread. OR, if you are doing it by hand, do you angle the thread chaser so it cuts a series of slightly deeper threads. Thus the tool needs to be held in the tool post at a similar angle?
Assuming I can sharpen it correctly and clamp it to the tool post, can anyone offer any suggestions or guidance? Do you cut it in multiple passes, in a similar way to a metal thread?
I assume I¡¯m going to have to make and use some sort of a travelling steady. My idea is to clamp it in the chuck and use a small freely rotating chuck at the tailstock end.
I believe I can get a much better quality and accurate thread using the gears than trying to use it hand held - on a very long tool holder, the same as the ones on a wood lathe. I have to check but I think the wood for the screws is normally Beech, if that¡¯s relevant?
Thank you in anticipation.
David of Abingdon(UK)
