Imperial size spanners

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mdt-son

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Hi

Tired of abusing my metric sized tool, and tired of fumbling in my rich toolbox, I am looking for a set of spanners with A/F matching BSF, CEI, UNF and UNC fasteners. I've looked at Whitworth spanners but found them to be useless for working on British bikes.

Firstly, are A/F for BSF and unified fasteners identical? No, they are not, if the Brits followed the ANSI B18.21 standard. For instance, a BSF 1/2" diameter screw requires a a spanner jaw size of .82" (20.83mm),
while a UNF 1/2" diameter screw needs a 7/8" A/F spanner (0.875" or 22.23mm). So, did Norton-Villiers adhere to the ANSI standard, or will their bolt head sizes follow the BSF norm?

Spanners need to be in the common sizes of fasteners found on bikes (i.e., in BSF terms, 1/4" to 1-1/16").

Please enlighten me, folks. Will I need two complete sets of spanners, one for BSF/CEI, and one for UNF/UNC?

Within the tool range sought there is some adaptability between the two (though the fit will be so-so), but in half the number of bolt sizes within the range, there is no cross-over connection.

What a mess!

- Knut
 
Last edited:
mdt-son said:
Please enlighten me, folks. Will I need two complete sets of spanners, one for BSF/CEI, and one for UNF/UNC?
Click to expand...

The answer is yes. The accross the flats measurements between the two are not compatible.

Plus, of course, you’ll need a third set becasue of those pesky Europeans / Japanese too.

Its not a mess, you simply need 3 separate sets. Which, considering each bolt has a nut, actually means buying 6 sets…

This is where a nice big shadow board pays huge dividends. I reckon I’ve saved about 15 years by not having to scratch around looking for the right spanners !!
 
Fast Eddie said:
This is where a nice big shadow board pays huge dividends. I reckon I’ve saved about 15 years by not having to scratch around looking for the right spanners !!
Click to expand...
Yeah, with 4 sets of spanners (in addition to metric spanners already present), a shadow board is a necessity.

Returning to my question, is there a source for buying NEW spanners made for BSF fasteners (to BS 1083:1965 spec) in the UK?
Spanners to suit unified thread fasteners are easy to get at.

- Knut
 
SteveBorland said:
Metrinch spanner’s and sockets work very well for both mm and AF, having a special rounded flank drive.
Click to expand...
"Metrinch tool can operate on both metric and inch series fasteners." Yes, there are some cross-references between AF (=Unified) and BSW/BSF, but there are gaps as well, one being the frequently encountered 3/8" bolt.
This is no viable solution for me. For unified fasteners only, it will work. However, having a rich set of metric spanners already, I may just as well buy a dedicated set of spanners for unified fasteners.

- Knut
 
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I have Metrinch and they are very good to cover all sizes of nut/bolt heads.
Only one drawback - depending on the spanner/nut combo there is usually a fair bit of "play" before the nut actually turns. Usually no problem but not good in tight spaces.
 
Last edited:
mdt-son said:
Yeah, with 4 sets of spanners (in addition to metric spanners already present), a shadow board is a necessity.

Returning to my question, is there a source for buying NEW spanners made for BSF fasteners (to BS 1083:1965 spec) in the UK?
Spanners to suit unified thread fasteners are easy to get at.

- Knut
Click to expand...

www.ebay.co.uk

BERGEN US PRO Whitworth Combination Combi Spanner Wrench Set 1/8" - 11/16" 10pcs | eBay

Whitworth Sizes Made From Heat Treated Hardened & Tempered. Which Is Heat Treated Drop Forged Hardened & Tempered. HAND TOOLS RANGE. PRO Blue & Original US.PRO. Their Full Product Range To. This High Quality Set Is Made From -.
www.ebay.co.uk
 
mdt-son said:
I've looked at Whitworth spanners but found them to be useless for working on british bikes.
Click to expand...
Why?
British Standard fasteners normally have Whitworth or BS (one size difference to Whitworth) size hexagons ( BA has its own spanner sizes).


mdt-son said:
Firstly, are A/F for BSF and unified fasteners identical? No, they are not, if the brits followed the ANSI B18.21 standard. For instance, a BSF 1/2" diameter screw requires a a spanner jaw size of .82" (20.83mm), while a UNF 1/2" diameter screw needs a 7/8" A/F spanner (0.875" or 22.23mm). So, did Norton-Villiers adhere to the ANSI standard, or will their bolt head sizes follow the BSF norm?
Click to expand...

Why would the "Brits" have "followed" ANSI B18.2.1?

BSF (and BSW) are BS 84, a specification that had nothing to do with American ANSI as far as I'm aware and almost certainly predates it as BSF was developed by Crompton and Field and introduced in 1908.

British Standard Fine - Wikipedia

en.wikipedia.org en.wikipedia.org


mdt-son said:
Please enlighten me, folks. Will I need two complete sets of spanners, one for BSF/CEI, and one for UNF/UNC?
Click to expand...

The Unified (UTS) series of threads used on British bikes are a different matter, therefore, require a different set of fractional jaw spanners.
Unified fasteners made in the UK would have been manufactured to BS 1580 (Parts 1 & 2).

mdt-son said:
Within the tool range sought there is some adaptability between the two (though the fit will be so-so), but in half the number of bolt sizes within the range, there is no cross-over connection.
Click to expand...

No crossover was intended as far as I'm aware.


mdt-son said:
What a mess!
Click to expand...

No, just a lack of understanding.
 
L.A.B. said:
Why would the "Brits" have "followed" ANSI B18.2.1?

BSF (and BSW) are BS 84, a specification that had nothing to do with American ANSI as far as I'm aware and almost certainly predates it as BSF was developed by Crompton and Field and introduced in 1908.

British Standard Fine - Wikipedia

en.wikipedia.org en.wikipedia.org
Click to expand...

Sorry Les, the logic was poorly expressed by me. What I meant is, if the Brits did follow ANSI B12.21 for the unified line of fasteners they used, the hex heads would be different to those of the BSW/BSF series. This discussion confirmed they are.

No crossover was intended .... Exactly, which is what causes a pain for mechanics.

- Knut
 
mdt-son said:
Sorry Les, the logic was poorly expressed by me. What I meant is, if the Brits did follow ANSI B12.21 for the unified line of fasteners they used, the hex heads would be different to those of the BSW/BSF series. This discussion confirmed they are.
Click to expand...

Ah, yes, they would be different from tools for British Standard fasteners.

I'm still slightly puzzled about your "Whitworth spanners being useless for working on British bikes" comment but it does depend on the age of the machine as one manufactured from approximately 1968-on is likely to have mostly Unified fasteners with the odd exception, especially on a Commando.

Triumph and BSA converted to the Unified system more rapidly than Norton who never completely succeeded in doing so and by which time British industry was converting to metric.
 
I have a full set of open, ring and sockets for all from metric, AF/impeial and of course WW, when working on any Norton Whitworth are very important for perfect fit, most engine nuts and bolts heads as well GB and primary are Whitworth size, AF will work on some and others with a bit of a tap and most of my 46 years of owning my Norton I have use AF/imperial tools but the last 10 years a full set of WW spanner/ring and sockets I now have the right tools for the job without forcing tools onto bolt and nuts, makes life a lot easier when working on my old Norton, I have also modified tools for those tight places and special tools that are needed, I just wish I brought WW tools when I first built my Commando/Featherbed combo all those years way back in the 80s, so important to have the right tools for the job.
Imperial size spanners
Imperial size spanners
 
L.A.B. said:
I'm still slightly puzzled about your "Whitworth spanners being useless for working on British bikes" comment but it does depend on the age of the machine as one manufactured from approximately 1968-on is likely to have mostly Unified fasteners with the odd exception, especially on a Commando.
Click to expand...
My exact word were " I've looked at Whitworth spanners but found them to be useless for working on British bikes". This is totally wrong of course. The tools are usable all right, it's the markings which causes confusion. This morning I got the idea of engraving Whitworth spanners with the "correct" size markings for BSF and BSC. Maybe that will work.

- Knut
 
mdt-son said:
The tools are usable all right, it's the markings which causes confusion.
Click to expand...

Ah, I see, the markings. Actually, I don't quite see as WW spanners are simply one hexagon size difference from BS so it shouldn't be difficult to select the correct spanner regardless and once understood then I can't see how it could result in any confusion. I guess after all this time I know what just about every fastener hexagon is on my Commando whether Unified or British Standard so instinctively pick up the correct spanner/socket.

mdt-son said:
This morning I got the idea of engraving Whitworth spanners with the "correct" size markings for BSF and BSC. Maybe that will work.
Click to expand...

I don't know if you were referring to working on a Commando but there aren't all that many WW/BS spanner sizes required and 3/16W, 1/4W, 5/16W, 3/8W spanners and a slim 3/8" square drive 1/4W socket for cylinder head nuts and bolts covers most of those.

If you were to follow Unified or metric spanner marking practice then you'd want to engrave them 0.338", 0.445", 0.525"...etc. :)
 
L.A.B. said:
Ah, I see, the markings. Actually, I don't quite see as WW spanners are simply one hexagon size difference from BS so it shouldn't be difficult to select the correct spanner regardless and once understood then I can't see how it could result in any confusion. I guess after all this time I know what just about every fastener hexagon is on my Commando whether Unified or British Standard so instinctively pick up the correct spanner/socket.
Click to expand...
Dear Les, that's easy for you to say, who has worked with imperial sizes and BSW/BSF fasteners a lifetime. For me, who grew up in a country in which metric fasteners always were the norm, I have to resort to a table, which makes tool picking slow, and once they are on the bench, I have to seek the table again. It will be a pain, initially at least. Maybe I will get the grip in 10 years? :cool: It's not the kind of knowledge I value the most, so I think engraving spanners is the solution for me. I will give your proposal due consideration!
Fairly new to wrenching the Commando, my other bikes are AMC models, thus focusing on BSF/BSC hex sizes will be imperative.

Thank you all for valuable input!

- Knut
 
mdt-son said:
Dear Les, that's easy for you to say, who has worked with imperial sizes and BSW/BSF fasteners a lifetime. For me, who grew up in a country in which metric fasteners always were the norm, I have to resort to a table, which makes tool picking slow, and once they are on the bench, I have to seek the table again.
Click to expand...

I'm going to have to disagree with you there as my introduction to the wonderful world of fasteners was also metric on Japanese motorcycles, therefore, no, I certainly didn't grow up with any useful knowledge of Imperial fasteners! ;)

Although perhaps I would have been more familiar with Imperial measurements and fractions, the metric system was rapidly replacing Imperial units in UK schools even before I left (and had no formal engineering training after I'd left) and I certainly knew little or nothing about Imperial/British Standard or Unified fasteners at that time and it's only because I've taken the trouble to subsequently teach myself about these things mainly due to owning British bikes and that wasn't until 1999 (and if I can learn enough about it to get by without confusing myself then it can't be all that difficult). :)
 
texasSlick said:
@ashman

How does the Jim Beam bottle factor into your collection of tools?
And where is the fridge I've heard so much about?

Slick
Click to expand...
It was on the work bench beside the bar fridge but cleaning the bench I put it up on the self for safe keeping but wasn't much left in it by this time, as well its metric a 1ltr bottle with about 300 m/ltr's left in it, can't remember what happened to the rest of the bottle lol
 
My first spanner set was Whitworth/BSF /CEI and the appealing thing about it is that there are so few spanners that are needed.

However recently I have run into a problem. The last lot of CEI thread nuts that I purchased here in Australia have metric heads. After complaining to the supplier I was advised that the nuts were made from metric bar stock because it is now too difficult to obtain the imperial bar stock. So the future may be more complicated.

ando
 

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