floor to chassis bolts

[JonB]

So does Miles I expect, and his are the proper oval shape.

[alan.barker]

If the Bobbin is solid in the grp and it is just the thread stripped fit a Helicoil (they are stainless).
Buy a Helicoil Kit which includes Tapping Drill , Helicoil Tap + fitting tool.
Job done in half an hour.
Helicoils are stronger than the original thread in the Bobbin. They are used a lot in the Aerospace Industry with no problems.
I have bought from "HILLCLIFF" Tools ltd UK with no problems
Alan

[mikealdren]

Genuine and own brand? They should do the job but they certainly aren't like the originals. I have a replacement bonnet for one of my cars and it has these bobbins.

I did hear at one point that someone (Miles Wilkins??) had the licence to manufacture the original pattern parts. They should be very easy to reproduce as they're just a simple casting, drilled and tapped.

[Bigbaldybloke]

I was stuck some years ago and needed a 1/4" bobbin.
Found a length of 3/8" square rod and cut off a suitable length, drilled and tapped it then went around the outside with my angle grinder to make a "waist" on it and duly fibre glassed it in as per the manual instructions, its still there today and is fine, i just made sure the bolt had a good coating of copperslip.

[rgh0]

Col Croucher at Elantrickbits cast up replacement bobbins to the original pattern and was selling them, I dont know if he still does this but he is on this forum and may reply

cheers
Rohan

[JonB]

Genuine and own brand? They should do the job but they certainly aren't like the originals. I have a replacement bonnet for one of my cars and it has these bobbins.

I did hear at one point that someone (Miles Wilkins??) had the licence to manufacture the original pattern parts. They should be very easy to reproduce as they're just a simple casting, drilled and tapped.

He has a big box full of them..

[reb53]

Is there a UK source for 1/4" UNC bobbins?

If you have a lathe, or a friend with one, it's a few minutes work to whittle one out of a bit of brass hex bar.
I've made dozens, including all the different types/sizes for a complete body shell.

Ralph.

[Chancer]

If I had to reglass in several bobbins and also to make them on my lathe preferring improvement over originality (they are after all hidden) and not wanting to ever do the job again I would use these:

https://www.bighead.co.uk/the-original-bighead/

Plenty of different head sizes, shapes, thread sizes, male female etc, standard is metric threads but they do imperial also, expect they will have 1/4 UNC unless they are only made for one exclusive customer in which case you could buy from them.

lighter, stronger, non corrosive, fit and forget.

[661]

If I had to reglass in several bobbins and also to make them on my lathe preferring improvement over originality (they are after all hidden) and not wanting to ever do the job again I would use these:

https://www.bighead.co.uk/the-original-bighead/

Plenty of different head sizes, shapes, thread sizes, male female etc, standard is metric threads but they do imperial also, expect they will have 1/4 UNC unless they are only made for one exclusive customer in which case you could buy from them.

lighter, stronger, non corrosive, fit and forget.

I had seen these and really like their stuff, especially the stainless cable tie holders, however was trying to keep the threaded stuff imperial...?????????????..yes, I ask myself why, too?

[661]

and, I can't do much at the moment as the car went off to the cage fitters this morning..

[Barney]

however was trying to keep the threaded stuff imperial...?????????????..yes, I ask myself why, too?

They do imperial as well - just need to speak with them. Cost uplift? probably!

[alan.barker]

For me it goes like this
1. thread in bobbin stripped, fit stainless steel free running helicoil.
2. hole too big for helicoil or oval wear e.g. bobbins for the bonnet in the wing.
Fit keyed insert which is even larger and made in stainless steel. With 4 keys you drive
into position to lock it solid. If the hole in the bobbin is worn oval you will need to make a
drill plate to guide the twist drill.
Alan