Sourcing a small, 1/2" bore pulley for a Mini Lathe (Flexispeed Mk1)

Hi,

I have a little Flexispeed lathe that I'm trying to get up and running. Unfortunately I'm not having much luck sourcing a suitable pulley for it.

The original has a 2-step pulley with a 1/2" bore. The maximum diameter of the pulley must be 2.5" otherwise it'll foul on the lathe itself but, unfortunately, I don't know the original diameters used.

The pulley on the motor, which I assume to be original, has a V-groove about 1/8" wide at the bottom.

I don't necessarily need a 2 step pulley - I'd be happy with anything just to get it up and running!

Any thoughts on where to source a pulley?

I will also need to source a belt for it so happy to take suggestions on that too.

TIA!

Hi Robert,

I assume you mean one of these:

The diameters are 2" and 2.5" with a 60 degrees groove. Can't help you with a source I'm afraid

HTH,

Rod

Hi Robert,

Welcome to the forum. It seems RDG has 2.5" Aluminium pulleys with 1/2" bore, unfortunately the groove is rather wide but it might get your lathe up and running.

BearingShop YK seems to be able to deliver 50mm pulleys (SPZ) and let you determine the bore size.

Thor

The pulley on the motor, which I assume to be original, has a V-groove about 1/8" wide at the bottom.

A V belt does not run on the bottom of the pulley groove. What is needed is the cross section of the belt (width at the outer edge).

Counter-intuitive as it may be … such a V-groove was often used for round-section belts

… at that vintage I would guess the use of leather.

MichaelG.

.

Edit: __  The archive of Model Engineering wisdom, however, quotes otherwise

https://www.model-engineer.co.uk/forums/postings.asp?th=125742

Edited By Michael Gilligan on 17/07/2023 15:35:37

I also have a Flexispeed, although it must be a different model as mine has three steps to that pulley.

For a belt, I use the green stretchy stuff that is sold in lengths, has a rough surface and is joined by heating the ends with a hot knife and pushing them together. It works well and does not slip easily. I cannot remember where I bought it; Steam Supplies or something similar, but I imagine that it is widely available.

James.

I found This company were one of the best, they will also machine any sized bore that you want, either imperial or metric and add keyways and grub screws for extra charge as well