Hi all,
First time posting here so please bear with me
I've owned my 13" for over twenty years now and for the first time I need to cut a metric thread. It's a bog standard 13" toolroom lathe with 6' bed and an English (8TPI) leadscrew. The Cat No. is CL8145C, SERIAL 152 01286. (not sure what year it was made). It has a dual tumbler gearbox. The current gearing is standard , a 24/48T stud , 80T idler , 64T gearbox drive.
I've done as much research as I can but I just can't afford a full metric conversion kit. So, I was wondering if I could compound a 63T spur gear with the 80T idler and use that to drive the 64T gearbox drive. It would all seem to fit in and there's enough adjustment on the banjo to be able to do it (a 63T is about 4.5" OD). I've measured the existing gearset and seems to be a bit of an unusual pitch (DP14).
By Compounding A 63T with the 80T I get a ratio of 1.269. Is that close enough? I only have a thread length of 2" to cut at 1mm pitch.
If this looks okay can anyone suggest a source for an 63T spur gear with a 14.5 PA?
Oh. Also what will happen regarding my thread dial?
Cheers
First time posting here so please bear with me
I've owned my 13" for over twenty years now and for the first time I need to cut a metric thread. It's a bog standard 13" toolroom lathe with 6' bed and an English (8TPI) leadscrew. The Cat No. is CL8145C, SERIAL 152 01286. (not sure what year it was made). It has a dual tumbler gearbox. The current gearing is standard , a 24/48T stud , 80T idler , 64T gearbox drive.
I've done as much research as I can but I just can't afford a full metric conversion kit. So, I was wondering if I could compound a 63T spur gear with the 80T idler and use that to drive the 64T gearbox drive. It would all seem to fit in and there's enough adjustment on the banjo to be able to do it (a 63T is about 4.5" OD). I've measured the existing gearset and seems to be a bit of an unusual pitch (DP14).
By Compounding A 63T with the 80T I get a ratio of 1.269. Is that close enough? I only have a thread length of 2" to cut at 1mm pitch.
If this looks okay can anyone suggest a source for an 63T spur gear with a 14.5 PA?
Oh. Also what will happen regarding my thread dial?
Cheers
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