HT Bolts

Looking for 6 off M20 x 220mm 12:9 HT bolts, plus real [1] nuts - any ideas for a source?
Thanks,
-- Peter Fairbrother
[1] ie not "full" nuts that only fools would accept, but ones that are at least 20 mm thick, and preferably thicker, eg 30 mm -
- just bought some M10 "full" nuts, which are 7.75 mm thick!
Anyone know how thick a full nut should be?
I'm guessing the major diameter plus an allowance of one pitch for the rounded-off thread ends in the nut, but "officially" it might even be as low as the minor diameter. Can't be less though, shurely?
(don't call mne ...
<rant>
I'm beginning to think that a whole lot of problems are caused by people buying cheap stuff, and not realising that cheap stuff is too cheap to do what they want... it may well be good enough for your job, if it will do the job, but don't expect it to do the job of a "proper" component.
Thing is, nowadays, why did I have to put "proper" in inverted commas (commae? - why not, it is from the Latin!)?
When the standard was "proper", then it was standard, and everyone knew what it meant - something which would do the job in all cases, except where a "special" wasn't required.
The standard might be overengineered for some jobs, but you knew it could do the more demanding, but still non-special, jobs.
Unlike the overcheap stuff, eg the MT2/MT3 adapter I bought from Chester (which wasn't particularly cheap anyway) which is more than 3 thou non-concentric, and badly out on angle too.
Recently came across this, which is relevant, especially the "Restricted rate of progression in UK welder training courses" section near the bottom:
http://www.weldsmith.co.uk/tech/edn/0901_BCweldcourse_present/index.html
"To an extent it is true that welding students trained under there conditions will find working with the correct welding consumables and conditions much easier later."
Hah! Overcheapness rules.
"The problems are
* The welds learned are not commercial welds (and UK students are often oblivious of this) * The student's time and effort is having much less value assigned to it"
Hah! Overcheapness rules, again!
</rant>.
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wrote:

http://www.roymech.co.uk/Useful_Tables/Screws/Hex_Screws.htm
Peter -- Peter & Rita Forbes Email: snipped-for-privacy@easynet.co.uk http://www.oldengine.org/members/diesel http://www.stationary-engine.co.uk http://www.oldengine.co.uk
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Peter Fairbrother wrote:

The problem you have Peter is dictated by your age and experience!
Like you, I still consider a 'full' nut to be at least the same thickness as the thread O/D and this is bourn out only by reference to my 1923 edition of Machinery's Handbook where a 13/16" Whit Nut is listed as being 0.81 - 0.82 thick, regretably metric sizes are not listed (it was printed before the age of enlightenment :) )
I was in the fastenings trade from 1972 to 1976 and even then a 'full' nut was still as thick as the O/D.

The reference cited by Peter Forbes is a 2001 and 2007 standard and agrees with the 1999 edition of Machinery's Handbook and they both confirm your suspicion the the minor diameter is now considered to be sufficient thickness.
I've never known a standard which calls for any allowance for rounded off threads though.
JG
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