Measuring PCD.

[blueST]

Anyone know how easy it is to measure PCD accurately? My friend has a home brew trailer of inditerminate origin and wants a spare wheel for it. Based on the tyre size, I suspect the wheels are from a van but we've no idea which one. They are four stud. Is there an idiot proof way of working out what the PCD is so we can buy a suitable wheel? I could just put a tape measure across opposite studs but would that be accurate enough?

Measuring the centre bore and offset shouldn't be too hard.

[blueST]

It's just occured to me the size might well be stamped on the back...

[Luther Blisset]

Insert in two studs diagonally, measure the distance across with verniers, then subtract the diameter of one stud (assuming both studs are equal diameter).

Studs should fit tightly of course.

ETA I mean diagonally opposed holes.

[blueST]

Luther Blisset said:

Insert in two studs diagonally, measure the distance across with verniers, then subtract the diameter of one stud (assuming both studs are equal diameter).

Studs should fit tightly of course.

ETA I mean diagonally opposed holes.

Got that, seems straight forward and a good excuse to use the calipers I got in Aldi!