Tap size, Imperial size of 36mm x 1.5mm

[BMG50]

Calling all workshop engineers! I am after a tap in 36mm x 1.5mm which is quite expensive. Anyone on the forum who would know the imperial size of 35mm x 1.5mm, as i can get imperial sizes much cheaper.

[hicky1300]

Basicallly if you have metric threads it is very difficult to find an imperial one that matches.
Different diameters (core & Outer) & pitches.
The size you want is a fine pitch. So imperial UNF will probably be the nearest but not sure if UNF or BSF go to this big as 36mm is nearly 1.5 inches.
Google the thread to see if there is a near imperial?
I have some large metric taps in my workshop but am not back in UK until 9th & I do not think I have one this big in fine pitch.
What it you are trying to do? Cut a new thread or restore a thread? I you are trying to restore a damaged thread you can buy thread file bars.
They are square with different pitches on each side.
Also another trick is if you have a spare male or female then use a three square (triangular) hand file & file 3 grooves in the male or female - this then works like a tap to restore a thread - it WILL NOT though cut a new thread.

[raymeketa]

If you are only trying to restore a damaged inside thread, I've found that a small grinding wheel in a hi=speed handee tool will work almost as well as a tap. You need to dress the wheel to a 60 degree shape (or whatever is necessary to match the thread shape) and have a go at it, carefully because those small grinding wheels will shatter.

Ray

[glevum]

If you are quick there is one on ebay for £15

http://www.ebay.co.uk/itm/36mm-tap-/...#ht_500wt_1363

[BMG50]

Thanks for spotting that. Many Thanks.