Nuts and bolts

Boathook

Boathook

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My 'new' boat was made early 1980's.

A few nuts and bolts are in awkward to get at locations and my existing metric and AF sockets don't fit well enough. On the metric, 9mm is to small and 10mm to big. Really the same with 3/8" and 7/16" AF.

There was a size, commonly used on boats back then but what was it. BSW comes to mind.

Does any one know of a chart / table where it gives the head sizes in metric and the correct AF, BSW, etc. before I go and purchase some sockets / spanners.

I have tried adjustable's but even my bacho ones seem to self adjust every time I take them off and then back on.
 
Boathook said:
My 'new' boat was made early 1980's.

A few nuts and bolts are in awkward to get at locations and my existing metric and AF sockets don't fit well enough. On the metric, 9mm is to small and 10mm to big. Really the same with 3/8" and 7/16" AF.

There was a size, commonly used on boats back then but what was it. BSW comes to mind....
Click to expand...

Unlikely but not impossible anyone was using BSW for new construction in the1980's. However, it does depend where these bolts are and what they're doing. BSW can still turn up on hardware and other items. Also pipe fittings invariably have BSW hexagons which does make sense with BSP threads.
 
Buy single hex power tool sockets. I find them the best for bolts with worn or undersize heads.

1/8 Whit is smaller across the jaw than 9mm IIRC. 3/16 W and 7/16 AF are very close in size. 11mm too.

0BA MIGHT be the odd size you need but quite obscure apart from electrical units.
 
I still have most of my spanners/sockets from working on British/American/French a/c. Lets say, quite a few.. Best are the 'flank drive' from Snap On. Similar boxed 1/4 and 1/2 inch drive set by German outfit. Though they not so 'smooth' as Snap On.
 
As someone already mentioned, it won't be Whitworth or British Standard if built in the 80s.
If 9 doesn't fit and 10 is too big, it's 3/8, which is 9.5mm. Our boat has a few fittings which are burred or marred, making some spanner sizes 'interesting', maybe that could be your issue too?
 
I understand that but I was talking about UNF and UNC heads. What I said was totally valid. These spanners are marked "AF", metric spanners are not so marked although they they do indicate an across the flats measurement.

So, in answer to your question, no, I hadn't forgotten anything. I was talking about "AF" marked tools for non-metric threads.
 
Spanners intended for use with for those non-metric bolt threads known as Imperial threads, eg BSW (British Standard Whitworth) and BSF (British Standard Fine) are not marked AF (Across Flats) but are marked with the thread type and diameter.

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No. Spanners intended for UNC and UNF threads are not marked with thread type. They carry the across the flats distance in Imperial units and the letters AF. BSF, BSW, BA (for instance) spanners are indeed marked with the thread type and the letters BSF, BSW or BA as appropriate but they are not directly intended for use with UNF/UNC heads although some might be close enough for some.
 

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Poignard said:
Spanners intended for use with for those non-metric bolt threads known as Imperial threads, eg BSW (British Standard Whitworth) and BSF (British Standard Fine) are not marked AF (Across Flats) but are marked with the thread type and diameter.

View attachment 206771
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Yes my workshop is full of such spanners. It is clearly for use with BSF or BSW threads. It is not intended for use with UNC or UNF threaded bolts or nuts.

I am talking about UNC/UNF only, for which you should be using a spanner marked AF. I am not talking about BA, BSF, BSW, Metric or anything else.
 
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