Page 1 of 1
Spanner and thread sizes
Posted: Fri Jul 15, 2011 11:19 am
by hdavy
biggingers list is great but can one assume that all the threads on a minor 1000 are BSF. ( Leaving out the funny metrics on MM's!) If not can someone list the variants?
Re: Spanner and thread sizes
Posted: Fri Jul 15, 2011 11:34 am
by IslipMinor
As a general rule the Minor body uses BSF threads and the mechanicals UNF/UNC. If you have a set of BSW spanners, the head size on BSW is one size larger than BSF, so to use them for BSF use 1 size smaller! For example for a 5/16" BSF nut/bolt use the 1/4" BSW spanner.
Re: Spanner and thread sizes
Posted: Mon Jul 18, 2011 2:11 pm
by hdavy
Have plenty of spanners but I would like to know the threads so that can get spare nuts and bolts. Which are UNF and which UNC? For example what are the screws holding the door pulls on and which are those fixing the glove box surround?
Re: Spanner and thread sizes
Posted: Mon Jul 18, 2011 10:19 pm
by les
I think the items you mention use self tapping screws, not engineering screws ie unf or unc
Re: Spanner and thread sizes
Posted: Mon Jul 18, 2011 11:35 pm
by bmcecosse
UNF in steel - UNC used in cast iron (eg cylinder head studs in the block) and in Al alloy (eg gearbox). The 'body' of the car is generally BSF .
Re: Spanner and thread sizes
Posted: Tue Jul 19, 2011 12:14 am
by mike.perry
You cannot rely on nuts and bolts being a specific thread, the cars are between 40 and 63 years old, many with a chequered history so over the years any old nut and bolt could have been fitted without the owner appreciating the difference
Re: Spanner and thread sizes
Posted: Tue Jul 19, 2011 11:33 am
by ASL642
And whichever they did use in the past will most likely have their threads chewed up by someone using the wrong screwdriver!

Re: Spanner and thread sizes
Posted: Tue Jul 19, 2011 7:54 pm
by MarkyB
The bolts you can buy are likely to be threaded all the way to the head.
Just because they are new and shiny it won't make them better than bolts that have a smooth shank for the correct length for the job in hand.
Nuts and bolts that haven't been mangled by DPOs (Dozy Previous Owners) or severely corroded can be prettied up with a rotary wire brush then treated and painted if that's your thing.
Re: Spanner and thread sizes
Posted: Tue Jul 19, 2011 10:10 pm
by bmcecosse
If they are threaded all the way up to the head - they are not 'bolts' - they are set screws! And they should not be used where 'bolts' are specified - since the unthreaded shank of the bolt is likely to be providing a fixed location/fit between parts - which the threaded shank will not do.