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Whitworth Question

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JPSmit

JPSmit

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I think <think> that the Austin 7 might have some Whitworth bolts. I still don't get the concept of Whitworth (but then I don't get the concept of many things)

I have imperial wrenches and I have metric - will either of these work on whitworth or do I need to buy new wrenches? (I don't think there is a downside here)
 
As I discovered on my MG, you can substitute *some* Whitworth tools with English or metric when you've got a Whitworth fitting.

But not all.

(Just want to cheer ya up ...)
 
Then there are all the Whitworth tools you already have; like the BSW Crescent wrench, BSF pipe wrench, BA pliers ...

Seriously, here are a few conversions that usually work. They are NOT precise, might fit a little tight or a little loose; but usually they'll work
3/16 BSW = 7/16" AF
3/8 BSW = 8 mm
7/16 BSW = 13/16" AF
9/16 BSW = 1" AF
11/16 BSW = 30mm (maybe, this one is pretty tight, I had to file down the nut just a bit)

BSF head sizes are always the same as the next smaller BSW, so for example 1/4 BSF takes the same wrench as 3/16 BSW (and 7/16" AF is just a bit tight).
 
To answer your first question, the Austin Seven, assuming you mean the pre-war car, is mostly a mix of BSF and BSW, with a sprinkling of BA for smaller, mainly electrical, sizes.
With deference to Randall, please try to get a set of BS wrenches (spanners in English). In particular you'll find the 1/4, 5/16 , and 3/8 BSF most useful, and in an old car, some will be tight. If you buy combo wrenches get 2 of each, so you can hold the bolt while unscrewing the nut, if you get my meaning.
I was brought up on Austin Sevens. What model do you have?
 
Roger said:
To answer your first question, the Austin Seven, assuming you mean the pre-war car, is mostly a mix of BSF and BSW, with a sprinkling of BA for smaller, mainly electrical, sizes.
With deference to Randall, please try to get a set of BS wrenches (spanners in English). In particular you'll find the 1/4, 5/16 , and 3/8 BSF most useful, and in an old car, some will be tight. If you buy combo wrenches get 2 of each, so you can hold the bolt while unscrewing the nut, if you get my meaning.
I was brought up on Austin Sevens. What model do you have?
Click to expand...

This is helpful - thanks! 1930 Boat Tail Tourer, thread is here:

https://www.britishcarforum.com/bcf/showthread.php?115792-Oops-I-did-it-again
 
Thought there was something familiar, I saw your post on Austinsevenfriends. You signed up to the right place there, pace Basil!

Good luck. I have nephews in Toronto, maybe I'll get in touch next time we visit?
 
I might still have a couple sets of wrenches; and possibly BSW and BA tap and die sets. Been stored a long time, and were not top quality to begin with, but they work and I'll sell a lot cheaper than MetricMCC. The plastic rolls for the wrenches are probably worthless by now, but the plastic boxes for the tap & die sets should still be OK.

PM me if you're interested and I'll see what I can dig out.

BTW, I agree on it being best to have the right tools. Was just trying to answer the question I thought you were asking :)
 
TR3driver said:
I might still have a couple sets of wrenches; and possibly BSW and BA tap and die sets. Been stored a long time, and were not top quality to begin with, but they work and I'll sell a lot cheaper than MetricMCC. The plastic rolls for the wrenches are probably worthless by now, but the plastic boxes for the tap & die sets should still be OK.

PM me if you're interested and I'll see what I can dig out.

BTW, I agree on it being best to have the right tools. Was just trying to answer the question I thought you were asking :)
Click to expand...

PM sent
 
"I still don't get the concept of Whitworth (but then I don't get the concept of many things)"

JP, Whitworth is just the oldest type of standardized fasteners. Your old Austin was built around the time that the Brits were converting from BSW to BSF.
 
Not quite, Waltese. BSF is a fine thread, BSW is coarse. They co-existed, and there are both in an Austin Seven.
Analogous to American fine and coarse threads, and Metric for that matter.
BSW threads are used for studs and bolts into the Austin's aluminium crankcase, for example.
 
The odd thing about Whitworth (odd in the sense that it's different), is that the head sizes were specified by thread size. Standardized wrenches also did not exist, so Sir Joseph Whitworth defined the head size for each fastener in proportion to the nominal thread size. That's why the actual "across flats" dimensions of Whitworth wrenches are so much larger than the nominal size. (Like a 3/16" BSW wrench being close to a regular 7/16" wrench. A 3/16" BSW wrench is the one that fits a 3/16" BSW bolt or nut.)

The heads didn't need to be as large for fine threads, so when BSF was defined, they used the next smaller "Whitworth standard" head for each bolt size. So that's why a 3/16 BSW wrench is the same as a 1/4 BSF wrench.

Just the concept of standardized fasteners was a huge step forward towards the industrial revolution. It seems obvious in hindsight, but Sir Joseph is the one who recognized it before anyone else. Still a great accomplishment, even if a few minor features didn't stand the test of time.

JP, I'm sorry, I got distracted by other things. I'll try to dig out what I've got this weekend.
 
I have sets of Whitworth wrenches that I use on my car, but if your in need of one in a hurry, get a pair of Proto fit-alls! :chuncky: PJ

View attachment 58650
 
PAUL161 said:
I have sets of Whitworth wrenches that I use on my car, but if your in need of one in a hurry, get a pair of Proto fit-alls! :chuncky: PJ

View attachment 58650
Click to expand...

Ooo excellent idea! Now, to be accurate are those left hand or right hand? or do I need to get both? :grin:
 
JPSmit said:
OK riddle me this batman - aren't BSW & BSF threads?
Click to expand...

Yes, BSW and BSF are thread types but as mentioned by others previously, they are/were much more complete standards which (as was also mentioned above) was quite unique for the time when they were introduced.

The things that set Whitworth apart from what we commonly use today are the root radii, crest radii, and 55 degree angle of the threads. Functionally the Whitworth threads are stronger with fewer stress risers than what we commonly use today. Modern threads (both metric and imperial) were introduced more for ease of manufacture and gauging/inspection than for their mechanical properties.

A point of contention for classic Mini owners is the tapped holes in the ends of the A-series crankshafts. They are neither modern, nor a true Whitworth size. They are a 5/8-16 thread cut with a Whitworth thread profile. The special 5/8-16 Whitworth profile taps are available, but they are very expensive. You CAN clean up the female threads using a much less expensive 5/8-16 UNS (special) modern tap but purists question doing that.
 
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