Pump drills I made back in the 70's

In Tunbridge Wells,England,famous for turned wooden items and other wooden items,the turners would get their wives to turn the lathe while they threaded the wooden boxes and their threaded lids! They used a SINGLE cutting edge cutter that was hollow in the "V",and sharpened on the inside of the V. The cutter looked similar to a V carving tool. The internal cutter had to be turned at a right angle,of course. These type cutters were referred to as soft wood type cutters.

Re:Thread combs; I sometimes tend to use old names for certain tools,coming from 39 years in a museum.

It would have helped in the old days,if the chasers had had their teeth angled to match the threads they were to cut. But,they were made straight vertical. When I make a chaser,I mount a comb blank in the tool holder. I put a threading tool in a short piece of round stock with the threading tool pointing straight outwards. Then,I run the blank past it with the QC box set on whatever thread I want. I take several passes until the thread is cut across the end of the chaser. That way,I at least have SOME angle to the teeth. All my old chasers are vertically cut,though.

Hope this makes sense. I'm not doing too well with descriptions this morning.
 
It is hard to imagine cutting a thread with a single cutting edge; it is hard enough to do it with a hand chaser; I admit that I've only done it once to see if I could do it (and I did). I think that hand chasers were made in days of yore by some folks using something like a hob, and making multiple passes on it until the thread was up sharp, but the most of them I've seen were made by Pratt & Whitney, and the threads have the relief on a angle, not on a radius, as if cut with a hob.
Regardless, they are a handy thing to have around; the shop that I apprenticed in had a good selection, and they were appreciated for what they could do.
I think that was one of the high values of a formal apprenticeship, that is exposure to the old ways, and the old timers passing on what they deemed important; I treasure their memories, at least most of them --- There were a few thorny personalities, and I'm sure that they felt the same about me!!!
 
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I read about the single point thread cutting at Tunbridge Wells in the Holtzafppel books I have.(I never can spell his name!!)
 
:applause:These are what you used to drill clock pivots in the 17th to 20th century...Very nice work....
 
benmychree said:
It is hard to imagine cutting a thread with a single cutting edge; it is hard enough to do it with a hand chaser; I admit that I'ne only done it once to see if I could do it (and I did). I think that hand chasers were made in days of yore by some folks using something like a hob, and making multiple passes on it until the thread was up sharp, but the most of them I've seen were made by Pratt & Whitney, and the threads have the relief on a angle, not on a radius, as if cut with a hob.
Regardless, they are a handy thing to have around; the shop that I apprenticed in had a good selection, and they were appreciated for what they could do.
I think that was one of the high values of a formal apprenticeship, that is exposure to the old ways, and the old timers passing on what they deemed important; I treasure their memories, at least most of them --- There were a few thorny personalities, and I'm sure that they felt the same about me!!!
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The shop that I apprenticed in had hand chasers as well, they had inherited them by virtue of scrapping a Navy repair ship and were allowed to keep all the small tools but not the machine tools; we used them there occasionally to clean up damaged threads, and subsequently, part of the collection came down to me. I have cut threads in brass with them, and once you get the lead established, it's not hard to do; in starting out, you hold the chaser at a shallow angle to the part, and make a rather circular swing with the handle to the right, this makes one or two teeth cut right on the corner of the part, and if one trace merges with another, the lead is established, then you just take light scraping cuts until the threads come up nearly sharp. Hand chasing was extensively used in brass work back in the day.
 
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