What’s this tap? Thread form?

What’s this tap? Thread form?

This topic has 10 replies, 8 voices, and was last updated 10 March 2021 at 20:01 by Howard Lewis.

Viewing 11 posts - 1 through 11 (of 11 total)

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10 March 2021 at 17:02 #533024
Ian Parkin
Participant
@ianparkin39383
I found in my large taps drawer and have being using this tap…

theres no markings on it but it measures 1 .31 “across the peaks and pitch is 11 tpi

so i can see that its a 1 5/16 11tpi and if i cut a 55 degree male part it screw perfectly into a hole tapped with this tap.

but what purpose would it have originally served

all my books don’t seem to have any taps of 1 5/16 diameter

Edited By Ian Parkin on 10/03/2021 17:04:03
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10 March 2021 at 17:02 #28035
Ian Parkin
Participant
@ianparkin39383
10 March 2021 at 17:06 #533026
Split Pin
Participant
@splitpin
1" BSP
10 March 2021 at 17:09 #533027
Tony Pratt 1
Participant
@tonypratt1
You need to get an older book showing the state of play before threads were standardised or it could be a 'special'

Tony
10 March 2021 at 17:09 #533028
Keith Long
Participant
@keithlong89920
Posted by Split Pin on 10/03/2021 17:06:57:

1" BSP
10 March 2021 at 17:10 #533029
Ian Parkin
Participant
@ianparkin39383
Thank you split pin
10 March 2021 at 17:12 #533030
Oldiron
Participant
@oldiron
Disregard

Edited By Oldiron on 10/03/2021 17:14:37
10 March 2021 at 17:16 #533032
Tony Pratt 1
Participant
@tonypratt1
Posted by Keith Long on 10/03/2021 17:09:52:

Posted by Split Pin on 10/03/2021 17:06:57:

1" BSP

Good shout!
10 March 2021 at 17:24 #533034
colin hawes
Participant
@colinhawes85982
Stubby taps always make me think…. Pipe thread. Colin
10 March 2021 at 18:18 #533046
noel shelley
Participant
@noelshelley55608
Yep ! As said 1" BSP but I think BSPP. The treads look parallel . Noel
10 March 2021 at 20:01 #533071
Howard Lewis
Participant
@howardlewis46836
Zeus Charts quote 1" BSP as 1.309" OD, 11 tpi so my vote is 1" BSP, like all the others.

DON'T bin it, it may come id handy one day!

Howard
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