Spark plug washers and Teflon shim

Any ideas where I can get spare spark plug washers for 1/4" x 32 plugs?

I've had a look at Hemingway and S/S but they don't appear to have them. The copper washers on eBay are too wide (difference between inner and outer diameters)

While I'm at it, who sells Teflon (PTFE) sheet in 5 or 10 thou thick sheets? No luck on eBay or the usual ME suppliers. If all else fails,I can get copper shim 0.2mm thick. I suppose that would be OK instead?

Dave
The Emerald Isle

I can't help you with suppliers, I'm afraid.

You haven't said whether you are thinking of using the Teflon (PTFE) for spark plug washers, but if so, I wouldn't. It tends to creep under high temperature and pressure, which can cause problems.

George B.

When I made the plugs for my RMC type B I also made the washers, Just drill a 1/4" hole in some thin copper sheet, mount on a mandrel and then turn the outside round. Or just turn down one sold for steam fittings.

I think non stick oven liner sheets are a source for the gasket material, at least that is what old John Bogs used to suggest. Plenty on e-bay. Mylar is another sheet that can be use dfor gaskets.

Edited By JasonB on 14/08/2020 07:02:17

Just looked at Minimag, they do them

Thanks, JB

I knew you would have the info!

Dave
The Emerald Isle

As an alternative, glow plug washers would fit, wouldn't they?

They will, but the question is still the same. Thankfully it has now been answered.

Dave
The Emerald Isle

We found that using PTFE insulated cable when measuring injection pipe vibrations, that the material eventually vapourised at the high temperatures and corroded the conductors. Also, was told that the vapour was poisonous, because the PTFE breaks down. And Fluorine, or anything immediately derived from it, (such as HF ) is not good for health.

So use at low temperatures < 100'C would seem to safe.

Howard