Door hinge brass bobbin thread size/pitch/type?

[AxemanS]

Anyone know what the thread should be within the brass bobbins glassed into the cill and scuttle to take the door hinge pivot bolts. The top bobbins look fine but lower ones have had incorrect bolts forced into them by the look of it - as the bobbins are still tightly fixed into the cill I don't really want to cut them out and replace so was going to try to re tap them - just need to know what taps are required. Any ideas?
It is possible the bobbins have already been replaced at some point as although the car is an '87 S1 the hinge pivot bolts have a 9.9mm shank rather than the 8mm I was expecting.

Thanks,
Dave

[Alan Whitaker]

Hi
All mine are M10, thats on a 88 S1

Alan

[magpies]

some early ones are M8 and the others are M10

The bolt size will be the 8 or 10 too, so easy to measure.

[phillpot]

"standard" metric coarse so M8 will be 1.25mm pitch and the M10 is 1.5mm pitch




Normans drawing gets around ..... clicky

Edited by phillpot on Saturday 31st January 15:21

[magpies]

some early ones are M8 and the others are M10

The bolt size will be the 8 or 10 too, so easy to measure.

[AxemanS]

Thanks gents - yes it appears to be an M10. Just need to find some M10 bolts with short thread now (hate cutting threads shorter as they never seem to 'start' properly again afterwards

[NaCl]

AxemanS said:

Thanks gents - yes it appears to be an M10. Just need to find some M10 bolts with short thread now (hate cutting threads shorter as they never seem to 'start' properly again afterwards

20mm length okay?

Try custom-fasteners.co.uk. I've been using these guys for years (mainly for motorcycle rebuilds)

http://www.custom-fasteners.co.uk/m10-150-pitch-bo...

[glenrobbo]

AxemanS said:

Thanks gents - yes it appears to be an M10. Just need to find some M10 bolts with short thread now (hate cutting threads shorter as they never seem to 'start' properly again afterwards

If you use a smooth file to file the cut end flat and finish off with a 45 degree chamfer around the circumference, the thread should start fine.

[phillpot]

AxemanS said:

Just need to find some M10 bolts with short thread now

Think you'll be lucky! it is not normal to have that much shank with such a short thread.


Put a nut on before you cut then, as said, clean up with a file and run the nut off. All should be fine

[magpies]

phillpot said:

AxemanS said:

Just need to find some M10 bolts with short thread now

Think you'll be lucky! it is not normal to have that much shank with such a short thread.


Put a nut on before you cut then, as said, clean up with a file and run the nut off. All should be fine

that's how I do it... keep cleaning the end up 'til the nut runs off with no extra force required. also in re fitting the nut. Put anti-seize copperslip in the end of the bobbins before fitting the door

[Barry S1]

I got these yesterday from a local shop they do bolts and fasteners

[AxemanS]

Looks like it will be a cut down thread length then😊

What was the length of those bolts Barry ( without head depth )and where did you get the new looking nylon tophat inserts from?

Thanks,
Dave ( currently trying to repair the knackered window regulators )

[Barry S1]

[Barry S1]

You can get the parts from Neil at ML parts 07971 726143 have you got a cunning plan for the regulator mine goes down nicely not good at going up again.

[greymrj]

phillpot said:

Put a nut on before you cut then, as said, clean up with a file and run the nut off. All should be fine

Amen to that . Where did you do your apprenticeship Phillpot? NEVER cut a thread without a nut on it first. File the end after cutting then screw the nut off and look for any sharp edges that need final 'fettling'.

On this occasion Phillpot I will wholeheartedly agree to the use of stainless . The original bolt is a very common size and easy to obtain. DO NOT use a fully threaded bolt whatever you do. You might consider using a stainless set screw (allen screw) which would be easier to access after. I am gradually changing most of mine over to 'allen' screws partly because it means I can carry a much smaller toolkit!!

[magpies]

I had a 5 year apprenticeship with the CEGB as Mechanical Maintenance Engineer - only managed to raise to 2nd Engineer before leaving to 'outside industry'

'course these days they won't use a file! a bench grinder and wire wheel is the way to go !!

Edited by magpies on Sunday 1st February 15:35

[phillpot]

Barry S1 said:

Always measure bolts from under the head or they'll turn up too short when you order them!


Die-nuts are a handy addition to any tool kit, I have some Snap-on ones but these Cheap 'n cheerful ones" could come in useful


.......... and a thread file




Apprenticed with Bristol Street Motors (Ford Main Dealer) many years ago!

[Barry S1]

:-)

[HvdWeerden]

Wrong side of the tape measure :-)

[glenrobbo]

HvdWeerden said:

Wrong side of the tape measure :-)

Depends which side of the Channel you're on Han

Over here, that's clearly a two and three-quarter inch 10mm hex head bolt.