Unknown Changewheels

I recently bought a couple of boxes of machine "junk". In amongst all of the bits and pieces appear to be two sets of lathe gear wheels. They are of a strange design and have two pins that provide drive. Anyone have any idea of what machine they might belong to?

Martin

DP, axle size, pin size and radius might be good for identification or ‘removal from the equation’.

They are quite possibly Drummond gears. Quite popular though I never understood why.

If you can tell: Bore size, Outside diameter - inches and mm, number of teeth, and thickness, it will help.

At the moment everyone is wondering how long is your particular piece of string!.

These details will allow the DP of the gears to be calculated.

Knowing the DP, the bore and the thickness (Tooth width and centre/hub thickness ), others on here may be able to make a better estimate of what machine the gears may suit.

Howard

Just measured one of them, all measurements are imperial

3.36 diameter

45 teeth

0.625 bore

two pin holes 0.18 and 0.2 diameter

inside to inside pin holes 0.77

outside to outside pin holes 1.15

didn't measure the thickness but I would guess at 0.5

Martin

I am almost sure that they are Drummond gears. They are probably a missing set or two. Well sort after by people who buy a lathe with non of only some gears.

DAVID

Sound like Drummond. I think one hole is straight, the other tapered.

Anyway, they should sell well.

Because they are 14DP and this size is difficult to find and difficult to find good quality cutters for making them. Used on Chipmaster, early Colchester (maybe Student & Master), Harrison L5 and derivatives (e.g. 140).

The DP calculates as 13.98, so 14 DP. So with two driving pins they are certainly not for a Myford.

Don't know the Drummond, but sounds a distinct possibility

Howard

Raglan also used 14DP and 5/8” bore. If original, I would expect them to have part numbers embossed on the casting.

Thank you for all of your thoughts and information gentlemen.

I've been out in the workshop tonight giving the gears a clean up to see what was there. There are four new ( still in bags) 3/4" wide gears that are marked L5 so I assume these are Harrison. There are twelve gears with the double pin holes that I assume are Drummond and two gears without pin holes that I'm guessing are Raglan these are all 1/2" wide. All have the same 14 DP.

Martin

I would concur with that L5 marking probably indicating "Harrison" as I own an L5.

There seem still to be a lot of Drummond lathes about, so finding a new home for those wheels should not be too difficult.

I'd be interested in the "L5" ones subject to fuller cross-identifying, if they don't suit any of your machines, as the set with my lathe seems incomplete.