Ingersoll lock screw size

[Aidan3]

I have an SC71 and have misplaced the screws that I took off when I painted the door. The screws are the four that go into the cylinder, I know they are just machine screws but can't seem to find the size of them anywhere, does anyone know what they are?

 

[crank39]

Ingersoll Cylinder Connecting Screws for SC71/SC73

Four Cylinder connecting screws Original Ingersoll part For use with SC71 & SC73 Automatic Rim Deadlocks Supplied at full length (51mm) Suitable for doors 40-60mm thick

www.ingersolllocks.co.uk

 

[Aidan3]

Thanks but at £10 delivery I was trying to avoid that since they are just machine screws.

 

[crank39]

@JohnD, timber door locks are his area, maybe he'll have an idea or have some to hand to measure

 

[JohnD]

I have got one in a crate somewhere. It is an old design, I think there is a good chance it will be 1/4"

Too old to be metric, I think. Have a go at measuring the holes.

I think Ingersoll is an American company, so may be UNF thread, or UNC?

It might be a Whitworth thread. (BSW)

American UNC is a copy of it, and almost exactly the same.

 

[JohnD]

Incidentally, and sorry, probably off topic, I found out that Meccano screws are 5⁄32" Whitworth. I found out when I was looking for some to fit an old Chubb lock.