General Calling identification experts...

[Bigvtwin996]

Here is a fixing.....
basicaly a "stud" that is fitted into sheet steel, and has a square section to stop it rotating, and the corners are "peened" over to stop it coming out...
they are not held tightly so obviously if you do not take care they drop out and are lost forever...

So what is the correct name for these fixings...and where can I obtain them...
they are about 1/2 in old money and obviously an imperial thread....

 

[the hobbler]

Peter---I think that you will find that they are called 'Coach-bolts' Look in the "Nuts/bolts/washers/screws" section of "B & Q". They sell them, and with metric threads as well! The head size will be a bit bigger than the bolt in your picture, but that might not be a bad thing. It is amazing what one can find out about on this Forum!!

 

[Bigvtwin996]

Peter---I think that you will find that they are called 'Coach-bolts' Look in the "Nuts/bolts/washers/screws" section of "B & Q". They sell them, and with metric threads as well! The head size will be a bit bigger than the bolt in your picture, but that might not be a bad thing. It is amazing what one can find out about on this Forum!!

if you will look closely at the round end... you will see they are not coach bolts...
they are specifically designed to be inserted into sheet steel and the square section is designed to retain it loosely in the sheet the head is set into a recess so the back plate remains flat... the heads are flat are flat....



better pic of one in place

 

[fiat500]

if you will look closely at the round end... you will see they are not coach bolts...
they are specifically designed to be inserted into sheet steel and the square section is designed to retain it loosely in the sheet the head is set into a recess so the back plate remains flat... the heads are flat are flat....



better pic of one in place

These aren't an exact reproduction of what you showed but would be just as effective.......self-clinch fasteners for sheet-steel.

https://trfastenings.com/products/c...-sheet-metal/Hank-Self-Clinch-Fasteners/Studs

 

[Bigvtwin996]

These aren't an exact reproduction of what you showed but would be just as effective.......self-clinch fasteners for sheet-steel.

I did find Clinch bolts and wondered if these were in fact the predecessors...
The modern clinch bolts are an option but I would like to try to find teh square ones.... reason being, if a clinch fastening is not perfectly inline then they can turn easily, where as the square ones do have a bit more leeway..

What is the correct term for oversize nuts compared to the normal size...
as you will see the nt used has a much larger face than you would normally expect...

 

[fiat500]

I did find Clinch bolts and wondered if these were in fact the predecessors...
The modern clinch bolts are an option but I would like to try to find teh square ones.... reason being, if a clinch fastening is not perfectly inline then they can turn easily, where as the square ones do have a bit more leeway..

What is the correct term for oversize nuts compared to the normal size...
as you will see the nt used has a much larger face than you would normally expect...

You're possibly meaning flange-nuts.

 

[the hobbler]

If you can't get exactly the correct bolt, a few minutes with a bench grinder would make a coach-bolt do the same job, in the same manner. Sometimes, you have look sideways at a problem, and use/modify what you CAN obtain, rather than what you would LIKE to obtain. I learnt this very quickly when restoring a small marine diesel (J2 Kelvin) that had been out of production for darn near 50 years and that I was planning to, and did, fit into my canal narrow-boat.

 

[Bigvtwin996]

You're possibly meaning flange-nuts.

A flange nut is one that has a stepped larger face?

I am meaning a nut that although has a small thread is actually twice the normal width
could it be a "pipe nut"?

The stud suggestion from a mate is:

"Flat head square step shoulder bolt"
Only problem so far is the supplier sells them for 0.01p each with a minimum order of 30,000

however Tom may actually be right in some way...
as I have now been informed that in the USA these are sometimes called
"Flat head carriage bolts"

 

[Bigvtwin996]

If you can't get exactly the correct bolt, a few minutes with a bench grinder would make a coach-bolt do the same job, .........

If it were one or two then fair enough... but I may be looking for a regular supply 100 a time...

Regarding the nuts... spoke to a mate who said as they are Imperial thread... then the size of the nut is 2x the diameter of the thread so that would mean that although they look larger they are simply 1/2 nuts.. that look bigger..


It is great to learn stuff that to some people is simple stuff...