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steamman:
Hi If you send me the DP of the gears you are using on your lathe I may be able to help you with a complete set of gears for your lathe as I have quite a few spare,Dont worry they are not expensive and could well help you out in the future.Ernie

DavidA:
Ok guys, Don't quite know how to put this, but here goes.

Andy,
Firstly, The pictures of the gear end of the head stock will have to wait while I move the lathe. There simply isn't room between the end and an adjacent wall to allow me to take any.

Now the embarrassing bit.
When I was looking (at a rather uncomfortable angle) at the gears I thought 'hang on, the gear on the stud appears to be the same size as the one on the spindle'. So I pulled it of and yes, it was (to within a few thou'). But on the face of it was stamped 54.
Then it dawned on me, it was 54 MM diameter (2.125 inch nominal), not 54 tooth. It was, in fact 34 tooth. I had not counted the teeth on this gear, just assumed that it was 54 from the stamp.
So the problem is solved; it wasn't a problem in the first place.

The joy at this discovery was tempered by the thought of all the humble pie I will have to eat for wasting all your time. Even now I am putting on my Armani hair shirt.

Ernie,

Thanks for the offer. Using the formula DP=(Number of teeth + 2)/outside diameter I get (34+2)/2.125 = 16.94. So I reckon that the DP would be 17. Allowing for machining errors.

As this seems a bit of an odd DP I would probably be better off with DP18 gears, or even 20.
As I have a primary drive set from the spindle I can key DP 18 to the face of the stud gear and use DP 18 for everything else.

Let me know the price and where you are.

Dave.

Fergus OMore:
16DP is a far more 'usual' diametrical pitch as used by several older firms such as Drummond. 20 DP is Myford et seq.

Whether this is of use is unknown. Merely chucked in for information.

Are you sure about the leadscrew?

Regards

andyf:

--- Quote ---Then it dawned on me, it was 54 MM diameter (2.125 inch nominal), not 54 tooth. It was, in fact 34 tooth.
--- End quote ---

:lol: :lol: :lol: :lol: :lol: :lol: :lol:

As you say, it doesn't matter what DP you use for the rest of the gear train, unless you use the existing stud gear as an idler (though you could always compound a 34T of a different DP with it). Indeed, you could use metric Mod 1.5 gears, which are about the same overall diameter. Actually, a 34T Mod 1.5 gear has an O/D of 54mm, which makes me wonder if Mod 1.5 is what you've got.

Cheap(ish) Mod 1.5 gears here: http://www.technobotsonline.com/gears/mod-1.5-steel-spur-gears.html . Teeth might be a bit wide though, at 17mm, and you wouldn't want the boss. I got some Mod 1s from them for my lathe; they had 15mm wide teeth and bosses, so I sliced off what I needed with the bandsaw, faced up the rough side, and then spent an age getting the resulting burrs off all the teeth. At first sight, it looks like they only supply up to 46T, but if you scroll down there are a further two pages going up to 120T.

Andy

DavidA:
Andy,

I also wondered if I had a metric gear. Checking the 34 tooth gear on the spindle (which looks original) it measured 2.1 inch dia which would give me 17.14 DP. So it looks as if it is a 17 DP set up with the stud gear being a 34 tooth mod 1.5 just tacked on to do the job. It doesn't mesh very cleanly. I've never used the screwcutting gear on this machine. I usually do that at work. Much easier to flick a few levers to Get whatever thread I want.
But as I'm thinking of retiring (again) in a couple of month I need to get my screwcutting capabilities sorted out.

Fergus,

I'm sure about the leadscrew, rather I was sure, I now need to check it again. :doh:

Dave

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