B s p

[Richard Farrant]

Originally Posted by Stew Robertson

here is a quote from the machinist handbook
My question is why would you a loose fitting thread or a free fitting thread to fasten an axle in . yes you guys are talking the same threads but not machine cut threads where they are designed to hold a load for a to attach a wheel where they can be torqued to the right spec.

PS I think you owe me lunch again

Your book is referring to American National Pipe threads, we are talking British Standard. Proof is shown in the original parts book that it is BSP. If a male and female thread are cut to the correct tolerances, there is no reason for them to be "loose fitting", that was referring to pipe nuts, this is a pipe thread form used elsewhere. In my work experience I have also come across BSP used in other roles, not pipe.

You might have to go hungry, no lunch yet

[Richard Farrant]

The real reason for using BSP for that diameter is TPI. Given the diameter, in BSW the nearest size would be about 7 tpi, in BSF it would around 9 tpi, so it makes sense to go to BSP and use a standard pipe diameter which give 14 tpi, much more sensible.

[Paul Dutton]

Originally Posted by Richard Farrant

The real reason for using BSP for that diameter is TPI. Given the diameter, in BSW the nearest size would be about 7 tpi, in BSF it would around 9 tpi, so it makes sense to go to BSP and use a standard pipe diameter which give 14 tpi, much more sensible.

And more grip!
I use BSP (no extra ' P' required) every day on hydraulic fittings! Anything up to 2" in normal use.
JCB, BENFORD/ THWAITS, etc, hell even some Japanese stuff like kobelco and Kubota use them.
Most European stuff is metric and Americans like Jic and Orfs (O Ring Faced Seal) and NPT which is close to bsp but differs on pitch slightly!
CAT use an inverted cone fitting like jic but with a bsp thread and komatsu the same but with a metric thread!!!
Confused??
Welcome to hydraulics, and don't even get started on the FINE and LIGHT threads!!!!

[Michael R.]

A Canadian made CTL series spindle with a BSP 7/8 - 14 die.

[Richard Farrant]

No argument there Michael !

[Stew Robertson]

You can call it what you like but it is a engineered speced machine cut thread
it could have been any thread 14/16/18 what every but it is still a 7/8 -14 thread machine cut and not with a die just like lots of equipment are built with none standard sizes and threads the BS is the only part that is right

[Michael R.]

The things people write to get out of a $6.98 CAD lunch special.
There are no emoticons for someone stirring the pot.