The motor pulley

Did I already mention that the centre of the pulley that came with the machine was about 0.5 mm off? That was the main reason for the severe vibrations when running it. The pulley was also 84 mm in diameter—much larger than the standard Myford pulley (which is 2”).

Ordering a new pulley

So I ordered a 50 mm pulley from RDG. It turned out to be a disappointment: it was designed for a different belt profile, and the belt slipped.

Well, you either own a lathe or you don’t: I decided to turn my own pulley. Here it is (it can just be seen between the countershaft mount and the guard for the primary belt):

I ground a cutter specifically for it (both sides at 17-degree angles, which is the correct profile). It didn’t cut cleanly plunging straight in, but feeding left and right worked fine. I ended up making the initial cuts to depth using a parting blade.

For future reference: v-belt types:

The primary belt is either a SPZ or a Z belt. On mine the width was 9.6 mm.

A further disappointment: the Fenner belt

The secondary belt was worn, and the replacement I bought from Myford Solutions was the wrong size. I had read a bit about Fenner link belts and ordered one from RDG. The main advantage is that you don’t have to remove the spindle to fit the belt.

Again, a disappointment. The belt rattles and slips easily, meaning I can only take light cuts. Here is the belt:

I’ve taken the measurements from the original belt (measuring the length after cutting it), and I’ll order a proper replacement sized to fit from a specialist supplier. I did that previously for the primary belt, and it fitted excellently. Standard V-belts shouldn’t slip anywhere near as easily as the Fenner link belt.

Just for reference, here is the diagram for the running direction of the belt:

Fruter disappointment: T-slots

To add to the frustration: I also bought some T-slot bolts from RDG Tools (supposedly “not worth making yourself”). They didn’t fit either—just a fraction too wide for the slot. Nowadays, I make them myself.