Help needed with Reduced Nuts. (UNF)

[OJCar]

I'm having difficulty locating a source of 5/16" UNF Reduced Hex Nuts.
5/16"UNF are normally 1/2" A/F, I need ones that are 7/16" A/F, as the original manufacture used.

The manufacturer no longer has any stocks and just suggests fitting 1/2" A/F sized nuts.
These can be got on, but are almost impossible to remove later (in one piece... ).

Normal 1/2" A/F nuts are just too big to fit on the design of brake back plate, to be able to get a socket or a ring spanner on.
Open ended spanners get camed off the nuts with these brake plates.

I know the Reduced Head Nuts exist, struggling to find them at present.

Supplier suggestions please?

 

[Erie Fred]

7/16 hex material and a lathe.....

 

[BrokenBiker]

7/16 hex material and a lathe.....

a lathe is usually a bit more expensive than a few nuts...even if the nuts are difficult to find

 

[BrokenBiker]

I'm having difficulty locating a source of 5/16" UNF Reduced Hex Nuts.
5/16"UNF are normally 1/2" A/F, I need ones that are 7/16" A/F, as the original manufacture used.

The manufacturer no longer has any stocks and just suggests fitting 1/2" A/F sized nuts.
These can be got on, but are almost impossible to remove later (in one piece... ).

Normal 1/2" A/F nuts are just too big to fit on the design of brake back plate, to be able to get a socket or a ring spanner on.
Open ended spanners get camed off the nuts with these brake plates.

I know the Reduced Head Nuts exist, struggling to find them at present.

Supplier suggestions please?

this any good. i know it doesnt specify the actual hex size, but does state they are small hex so might be worth giving them a bell to see if they know or can measure

Part Number 21-1908

NUT 5/16 UNF SMALL HEX - Classic Triumph Part Number / SKU: 21 -1908

tricor-andy.com

 

[hotponyshoes]

K-Nuts or 12-Point nuts?
Not sure what size the hex is on a k-nut but I could dig one out and have a look if you can't find out..

 

[cocker]

a lathe is usually a bit mroe expensive than a few nuts...even if the nuts are difficult to find

There are plenty of nuts on here , with lathes .

 

[Smallfry]

What about flanged nuts ? They usually have a smaller than standard hex, provided the flange will fit your application.

 

[BrokenBiker]

What about flanged nuts ? They usually have a smaller than standard hex, provided the flange will fit your application.

the flange could be removed...bolt in a drill, jam nut and flanged nut spun against a flap disc at a bit of an angle to avoid clipping the corners of the hex...or pressed to a belt grinder

 

[OJCar]

might be worth giving them a bell

I'll try them in the morning.

That has reminded me that 5/16" UNF Reduced Hex Nuts were used on some Triumph bike's oil pumps.

Not sure what size the hex is on a k-nut but I could dig one out and have a look if you can't find out..

If you could see what diameter the flange part is on the K-Nut please?
The A/F size is not as vital as much as getting in there properly.

 

[OJCar]

There are plenty of nuts on here

and not all of them have lathes...

 

[hotponyshoes]

If you could see what diameter the flange part is on the K-Nut please?
The A/F size is not as vital as much as getting in there properly.

0.52"

Hard to measure the A/F size but I think it's 3/8"

 

[Kram]

Alternatively buy normal nuts and grind half the difference per side until they fit a socket. Not much to come off.. if you get several together using a flat surface to superglue them, blue and scribe a line it can be done quite well by hand.

It appears that 7/16" works out as 11.13mm
I think I have a 5/16" UNF tap, would have to check. How many do you need?
If you cover the beers and postage I could mill some.

Do you need any specific grade? Would en16m/606m36 be adequate (free machining with sulphur, so not recommended for welding)

 

[hotponyshoes]

I don't know enough about imperial but would there be enough meat in a nut with a 7/16 a/f to drill out the existing thread and tap it to 5/16?

 

[mr haynes]

As @Kram suggests, try drilling and tapping a 7/16af nut.
Isn't a normal size between 7/16 and 1/2.
Pretty sure i don't have any in my nuts tubs or would offer.
I'm assuming a 7/16 af bolt isn't appropriate for the usage?

 

[zzr1200]

A standard 1/2" nut and use a mill to reduce across flat...... no mill...... use a flat file..sorted..

 

[Ton-up]

https://www.ebay.co.uk/itm/14475825...id=10001&customid=eb:g:vms:eb:p:144758252929;{GCLID}&ad_type=pla&loc_interest_ms=&loc_physical_ms=9217050&gad_source=1&gad_campaignid=1557785751&gbraid=0AAAAADmMgihsJYIpPfo6HaI0W-mfhtKS_&gclid=Cj0KCQjw6bfHBhDNARIsAIGsqLi32FHUpBKmB3jGCqo7lTvNaIZpz8FS4BbwjqqylcwdYEPFbChxk5oaAgmCEALw_wcB

 

[OJCar]

Thank you all for your suggestions.
(Only glad no-one suggested building up weld around a 5/16 UNF Copper Bolt ... )

I've ordered some K-Nuts from https://www.msar.co.uk/
They had somewhat better pricing/postage than some of the other suppliers!
(One supplier wanted £6.30 a nut, £9.60 to post and also a "small order fee" of £5.45 ... )

 

[Erie Fred]

a lathe is usually a bit more expensive than a few nuts...even if the nuts are difficult to find

Admit it.....you don't have a lathe, and you need one......
"Lathe Envy".....

 

[Erie Fred]

There are plenty of nuts on here , with lathes .

Guilty as charged...