Schrader Tap

Hello , I need to tap an internal thread for a valve cap 8v1 .307 X 32 tpi , now the question is do I need the schrader tap which is expensive or I’ve found a 5/16 x32 tpi tap at a very reasonable price ,would the unff tap be ok

I often make the round knurled retaining nuts for motorcycle inner tubes because new tubes tend to come with hexagon nuts and do not look right. I use 5/16" x 32 tap without problems.

Thanks Chris

Whilst on the subject of Scrader valves, what is the internal thread that takes the valve insert?

Mick

I thought that Schrader valve threads are 0.75mm pitch, although if U S A manufacture are much more likely to be to an Imperial standard.

There was a similar discussion on here, some time ago.

If you can find it, that may be a help.

Howard

32 tpi for that diameter

I think the insert is 0.210" x 36 on a car size v8 valve

Edited By JasonB on 02/01/2019 11:45:48

Perhaps this summary would be useful: **LINK**

https://ipfs.io/ipfs/QmXoypizjW3WknFiJnKLwHCnL72vedxjQkDDP1mXWo6uco/wiki/Schrader_valve.html

... unless, of course, someone has a more definitive source that contradicts it.

MichaelG.

Edited By Michael Gilligan on 02/01/2019 14:19:01

Michael's link gives it at 5.30 x .7 something , but fiddling around this morning, !BA is as near as dammit and seems to work well.

Mick

The Model Engineers Handbook gives 1 BA as having a top diameter of 5.3mm, and a pitch of 0.9mm

Howard