B s p

[Michael R.]

Yes, BSP, or British Standard Pipe. Not to be confused with another BSP. Apparently there are two of them, one parallel, the other tapered. Therefore BSPP and BSPT.
Doug L. and I were discussing the thread size found on bogie spindles. The good book FUC-03 sez they are 7/8x14 B.S.P.. (see page 153 or 156)

Hmmm........ never a dull moment with BSF, BSW, UNF, UNC and now BSP(P). In my mind's eye I can see those Brit engineers smiling ... "exactly, my dear Michael".

A quick look through the MLU archives provides an assortment of thoughts on the thread size, but I could not find any post or "thread" (the MLU pitch) that revealed more than what the FUC-03 manual states. Initially, I thought the manual must be wrong, as the spindle thread O.D. measure better than 30mm. But no, it appears the 7/8 BSP thread relates to the bore size of a pipe for which the thread is suitable. The nominal size is somewhat larger than the stated number.

The drawings for making a spindle drift from a discarded early series TL334 spindle do not mention the thread. The spindle nut TL 335 - CTL 335 is simply called a Nut - spindle, without a size stated.

Now to find a die nut in 7/8 x 14 BSP(P).

[rob love]

We have the same thing with National Pipe threads here in North America. We have NPT and NPS....tapered and straight. Tapered will tighten up after a few turns, and straight will go through just like a nut and bolt.

A quick google will give all the specs to cut the BSP parralel threads. Even a few suppliers of the taps and dies, but I would go with a lathe myself. When you get to these larger sizes, by the time you buy the taps and dies, then the handles to match, you are well onto your way to buying a decent used lathe.

[Lynn Eades]

Over here the two BSP threads are referred to as:
BSPP parrallel
BSPT Tapered.
Without the bits and pieces in front of me, I am doing the hear say, rumour, and opinion thing, but I think the bogie axle thread is all UNS (without looking up a chart) and I think they are completely interchangeable with the Australian carrier (about the only bits that are, save the bearings)
So Michael, get your charts, guages, and an axle out, and have a look.
Give us the dia. and tpi, or the result
UNS at 1 1/4" is 14 tpi. Is that it?

I have looked and found a chart for BSPP,(and it makes more sense now) with a 14 tpi thread as you say Michael R, so kindly disregard the ANS reference.
Like Rob says, Chase the threads in a lathe.

[Michael R.]

The thread O.D. measures up over 30mm and TPI is 14 .

[Ron Pier]

These days I'm more used to dealing with motorcycle pipes of 1/4-5/16-3/8 BSP threads. Back in my Dry Cleaning days we had to thread 1/2-3/4-1" and larger pipes for steam. I guess these bogie wheel tubes were dealt with as per a plumbers pipe.

Ron

[Ben]

Having had a look I think they are all parallel threads. The conduit uses a pipe thread too.

We had the bloke at work last Friday who services all our compressed air and vacuum lines. He looked at the conduit thread and had nothing to fit in his van. We suspect its a size that's fallen out of favour today. The pipe thread sizes can get confusing as Micheal has said, the size listed isn't the thread OD as on a bolt.

Thread cutting on a lathe can produce any thread you desire. As long as you have the pitch and TPI info you can turn an internal or external thread to your chosen diameter. This is how I did the filler necks on the fuel tanks.

[Lynn Eades]

Hi Ben the thread on the conduit is "conduit" thread the older electricans had the gear I think it is all 16 TPI, and one size matches with UNF (5/8???)

[Richard Farrant]

Originally Posted by Michael R.

Now to find a die nut in 7/8 x 14 BSP(P).

Hi Michael,
Hope this is of help to you;
http://www.ebay.co.uk/itm/BSP-DIE-NU...-/110617414636

[Michael R.]

Yes, thanks Richard. M.

[eddy8men]

i'm sure I read somewhere that bsp and bsw were the same thread but I am no engineer so don't hold me to it.
however I will go to my shed and have a look for you Michael as you never know I might have what you need in my bucket of assorted old taps and dies

rick

[Michael R.]

Thanks Rick, e-mail sent to you.

I understand the BSP series follows the standard, non-modified Whitworth thread profile.
What I have not found is a 7/8 x 14 in other than BSP. Sir Miles Axlerod from Cars would be impressed. A trail of redundant threads.
"And then I remembered what they said about old British Engines, if there ain't no oil under 'em, there ain't no oil in 'em."

[Lynn Eades]

Rick BSW in that size would be about 8 TPI