13 replies to this topic

[Hendred]

Hi everyone,

 

What size are the wheel nuts on 12" wheels in mm's and old money?   

 

Thanks

[Dan]

3/8" UNF. They are NOT metric at all. The seat shape and nut length depends on the wheels fitted.

[A-Cell]

Thread size 3/8in UNF
Spanner size 11/16in A/F
Metric spanner 17mm

[Hendred]

Thanks chaps

[M J W J]

Thread size 3/8in UNF
Spanner size 11/16in A/F
Metric spanner 17mm

 

DON'T use a 17mm spanner.

 

You will round the corners off on the nuts as one garage kindly did to my mini, despite me telling them that they were imperial nuts.

[Cooperman]

For UNF nuts & bolts NEVER use a metric spanner.

[Lennyliverpool]

sorry to high jack this thread - but i have just discovered i have a flat on one of my 12" wheels

Do all mini wheels have locking wheel nuts? - because i have not got a key.....!

 

How can you tell if you have or have not - and more importantly how would you get it off?

 

[Hendred]

If you have it may have a cover on the nut that is the locking wheel nut, look very closely at all 4 nuts on each wheel and you should be able to tell if one looks slightly different.  If you have no key I use a chisel but someone else may have an alternative solution

 

Hope this helps, let us know how it goes

[A-Cell]

Thread size 3/8in UNF
Spanner size 11/16in A/F
Metric spanner 17mm

 
DON'T use a 17mm spanner.
 
You will round the corners off on the nuts as one garage kindly did to my mini, despite me telling them that they were imperial nuts.

Since 17mm is 18 thou smaller than 11/16, it does not damage 11/16 in nuts, maybe garage used 18mm!

[A-Cell]

For UNF nuts & bolts NEVER use a metric spanner.

In general I agree, however some sizes are exactly the same as you well know, eg 14mm and 9/16 in, and some are usefully just that bit smaller to use on old corroded, reduced size bolts/nuts.

[GraemeC]

Most aftermarket chrome nuts are the correct UNF thread but 17mm AF socket size.

[M J W J]

 

For UNF nuts & bolts NEVER use a metric spanner.

In general I agree, however some sizes are exactly the same as you well know, eg 14mm and 9/16 in, and some are usefully just that bit smaller to use on old corroded, reduced size bolts/nuts.

 

 

14mm and 9/16th are NOT the same. There is about 0.29mm difference between them which in thread and nut machining tolerances is HUGE.

 

Its people thinking they are the same that causes damaged nuts with corners rounded off, which results in more work for other people trying to remove them.

 

In the case of the ones being damaged on my mini. They were the original nuts and a 17mm socket on an impact gun was enough to damage them. After I kicked up a bit of fuss they let me have the tyre done for free as it only came to about £30 in total and I had a spare set of nuts.

 

The difference between an 11/16th and 17mm is 0.4625mm. 18 thou is quite large in tolerance terms. Lathes, milling machines and other screw cutting machines usually work to a much tighter tolerance than that. 1 inch is 25.4mm not 25mm as a lot of people think. Again that 0.4mm is a big enough difference in general machining terms.

 

 

Most aftermarket chrome nuts are the correct UNF thread but 17mm AF socket size.

 

If this is true that's great as I don't have a wheel wrench for my mini so if I can get after market nuts that are the correct thread on the inside and 17mm on the outside I will do so. This means I can buy one of those replacement 17mm tyre wrenches.

[GraemeC]

If not, just get to auto jumble and buy a cheap 11/16" AF socket and a cheap 1/2" knuckle bar.

[M J W J]

If not, just get to auto jumble and buy a cheap 11/16" AF socket and a cheap 1/2" knuckle bar.

 

That is plan B.

 

I think I have a spare 17mm wheel wrench somewhere so the replacement nut idea is a better one. I want to fit chrome ones anyway as I am restoring my mini.