Thanks for that explanation Simon, I had never quite understood about the 2 sizes on the Whitworth spanners before, it makes perfect sense now! Thanks!
As far as I have seen if you buy any new BSF/BSW hardware, which is getting hard to find, it will be the BSF sized heads/nuts. I just know as as someone new to all this figuring out the differences between bolts and threads and spanners and so on isn't easy.
Good video I’m very glad to hear your using the correct nuts + bolts on your restoration. I think everything you said sounds about rite , my understanding is in the beginning there was simply “Whitworth threads” aka “ BSW British standard whitworth “ or sometimes marked simply as “W” these were the 1st standardised threads in the world created by a guy named Joseph Whitworth of Manchester ( incidentally it was he who 1st decimalised the inch too among other fantastic things ) anyway these were fine for locomotives and bridges etc but with the advent of cars etc a finer thread was required so along came BSF (British standard fine) these used exactly the same range of hex sizes as the older BSW but were all 1 size smaller so only 1 set of spanner’s was required for both thread pitches hence two sizes on 1 spanner. Very intuitive actually once you get your head round it , to tighten a 1/2” bolt you use a 1/2” spanner - perfect ! Unfortunately tho due to material shortages during the war all head sizes were reduced to 1 size smaller to save steel in production so your same spanner set will still fit any BSW or BSF bolt just depending on the age of the bolt and the age of the spanner it may give the wrong size on it. In summary then if you have a set of whitworth spanners you WILL definitely have 1 to fit any BSF or BSW bolt regardless of age just it may state the wrong size on the spanner. The earlier usually pre war nuts and bolts are easy to spot as the hex size is noticeably bigger. Fun fact all the BSW range of threads are the same tpi as UNC accept the 1/2” and can actually be interchanged but this is not recommended as they have a different thread angle UNC - 60 degrees BSW 55 degreees
Thanks for the comprehensive reply! I recently sorted my boxes of random hardware into bolts, nuts and washers but haven't gone as far as working out what threads everything is!
It's bad enough when you need to find the wrong spanner in the shed and have to go across the workshop to go get it, imagine if it happened while one the road with only a period set of tools!
Not really. But sort of. BSW/BSF sizes as marked refer to the diameter of the bolt. Metric and AF (for SAE nuts and bolts) type spanners are measured by the size of the bolt head. So a 1/2 BSW definitely won't be the same size spanner as a 1/2 AF. But sometimes the spanners are close enough to sort of work but I wouldn't recommend it! This is the best chart I have found that shows the actual spanner measurements for each type: www.baconsdozen.co.uk/tools/conversion%20charts.htm
Thanks for that explanation Simon, I had never quite understood about the 2 sizes on the Whitworth spanners before, it makes perfect sense now! Thanks!
As far as I have seen if you buy any new BSF/BSW hardware, which is getting hard to find, it will be the BSF sized heads/nuts. I just know as as someone new to all this figuring out the differences between bolts and threads and spanners and so on isn't easy.
Good video I’m very glad to hear your using the correct nuts + bolts on your restoration.
I think everything you said sounds about rite , my understanding is in the beginning there was simply “Whitworth threads” aka “ BSW British standard whitworth “ or sometimes marked simply as “W” these were the 1st standardised threads in the world created by a guy named Joseph Whitworth of Manchester ( incidentally it was he who 1st decimalised the inch too among other fantastic things ) anyway these were fine for locomotives and bridges etc but with the advent of cars etc a finer thread was required so along came BSF (British standard fine) these used exactly the same range of hex sizes as the older BSW but were all 1 size smaller so only 1 set of spanner’s was required for both thread pitches hence two sizes on 1 spanner.
Very intuitive actually once you get your head round it , to tighten a 1/2” bolt you use a 1/2” spanner - perfect ! Unfortunately tho due to material shortages during the war all head sizes were reduced to 1 size smaller to save steel in production so your same spanner set will still fit any BSW or BSF bolt just depending on the age of the bolt and the age of the spanner it may give the wrong size on it.
In summary then if you have a set of whitworth spanners you WILL definitely have 1 to fit any BSF or BSW bolt regardless of age just it may state the wrong size on the spanner.
The earlier usually pre war nuts and bolts are easy to spot as the hex size is noticeably bigger.
Fun fact all the BSW range of threads are the same tpi as UNC accept the 1/2” and can actually be interchanged but this is not recommended as they have a different thread angle UNC - 60 degrees BSW 55 degreees
Thanks for the comprehensive reply! I recently sorted my boxes of random hardware into bolts, nuts and washers but haven't gone as far as working out what threads everything is!
Well now I know! Thanks!
It's bad enough when you need to find the wrong spanner in the shed and have to go across the workshop to go get it, imagine if it happened while one the road with only a period set of tools!
Will britool wrenches in bsw sizing work on regular sae nuts and bolts?
Not really. But sort of. BSW/BSF sizes as marked refer to the diameter of the bolt. Metric and AF (for SAE nuts and bolts) type spanners are measured by the size of the bolt head. So a 1/2 BSW definitely won't be the same size spanner as a 1/2 AF. But sometimes the spanners are close enough to sort of work but I wouldn't recommend it! This is the best chart I have found that shows the actual spanner measurements for each type: www.baconsdozen.co.uk/tools/conversion%20charts.htm
@@asciimation does the disparity in size get bigger or smaller when getting into 1" And above imperial bolt sizes?
@@asciimation thank you for the info