Meccano bolts

I guess this is the right newsgroup for this one. Its not quite Sieg v Myford but you can't get more uk.rec.models.engineering than meccano.....

My 7 yr old has one of the (French manufactured) meccano sets. Alas, he is having difficulty because the nuts and bolts keep coming undone - and its turning him off it.

I don't seem to remember having that much trouble 45 yrs ago when i used to be an avid fan. Its not just him - even when i tighten them, they will still work loose with ordinary handling.

The bolts are different from those I remember - these are allen headed black things (diameter outside thread 3.5mm - sorry haven't got a thread gauge). The nuts look similar to my youth - square not hexagonal but i remember them as marginally thicker. There are many more bolt length options than I ever used to have as well.

There are some nyloc nuts in the set and I have also locknutted the critical ones and tried the old varnish trick on the thread but none of these are a sensible solution. I did ask the chap with all the Army Meccano models at Brighton exhibition earlier this year but he didn't have the problem.

I guess the nuts or bolts are cheapo with too much clearance and I would be perfectly happy to buy him some good ones if it means he xxx we can get on with the big crane with motor - but what do I get and where from - and would normal hexagonal nuts be Ok for 7 yr old fingers?

Ken

Reply to
Ken Wilson
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meccano.....

Alas, he is

headed black

remember them

these are a

problem.

They should be 7/32 Whitworth. Here are some on ebay:

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AWEM

Reply to
Andrew Mawson

Is 3.5mm not a common(ish) metric size, and given that it's french, it's highly unlikely going to be imperial.

And a 7yo, is more likely to manage normal hexagon nuts of that size far better then you!

Reply to
moray

They were whitworth of some sort, and yes they should be fine for 7 year old fingers, IIRC I was 5 when I got my first meccano set, a big yellow crane, for xmas :) I dont remember having problems with them coming undone, and meccano takes the stresses *much* better than technic lego ;)

Dave

Reply to
dave sanderson

I was a Meccano kid (red/green era) and the screws and nuts were always coming loose on anything powered. On the other hand if you locknutted joints it was a real pig to undo the nuts (the pain!)

Reply to
Steve W

You sad bastard knowing that......................

-- Regards,

John Stevenson Nottingham, England.

Visit the new Model Engineering adverts page at:-

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Reply to
John Stevenson

thread

from -

Sad bastard I agree! However all I did was google Meccano bolts, find the ebay ad which told me the size, post it into TinyURL, and reply to the O/P - took all of 15 seconds. I knew that they were a none preferred Whit size but not which

AWEM

Reply to
Andrew Mawson

It's still the same 5/32 bsw thread - but the new French stuff has slightly smaller holes than the old meccano.

However m4 nuts and bolts will fit in the new holes, albeit needing a gentle squeeze sometimes if the paint is too thick. With m4, you have a complete range of nuts and bolts readily available.

yep! But get him some box spanners too.

-- Peter Fairbrother

Reply to
pete

It's still the same 5/32 bsw thread - but the new French stuff has slightly smaller holes than the old meccano.

However m4 nuts and bolts will fit in the new holes, albeit needing a gentle squeeze sometimes if the paint is too thick. With m4, you have a complete range of nuts and bolts readily available.

yep! But get him some box spanners too.

-- Peter Fairbrother

Reply to
pete

Sad - and wrong! They were, and still are, 5/32 Whit, not 7/32.

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-- Peter Fairbrother

Reply to
pete

You could also try american 8-32 nuts. I don't know for sure whether they will work though.

Reply to
pete

undone -

reply to

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Odd as if you look at that url I posted it would seem to be an original Meccano packet (from Binns Road in Liverpool - now THERE'S a sad bastard!!!) which distinctly says 7/32", though I agree 7/32" at

5.5 mm seems a tad large.

Have another look:

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AWEM

Reply to
Andrew Mawson

[...]

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7/32" long?

-- Peter

Reply to
pete

Nuts:

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5/32 bsw

Bit expensive, but ...

-- Peter Fairbrother

Reply to
pete

In article , Andrew Mawson writes

Well, I had a firm recollection that they were 5/32 BSW, so I just went and checked dome of my Meccano bolts (even sadder bastard!) and sure enough, 0.1485 - 0.1520" - a slightly loose 5/32 - x 32 tpi.

The ones from my childhood (early 60s) were brass cheeseheads, the more recent ones are a mixture of CH and RH types, mostly chromed.

I always found lock-nutting worked well for moving parts, certainly within the limits of what you could expect of Meccano structures.

David

Reply to
David Littlewood

David

I can't challenge you in the "sad bastard" competition as I have very little Meccano and nothing more recent than the early 60's. As my life at the moment consists of rushing up and down the M4 caring for ailing relatives, I took the opportunity during yesterdays visit to venture into a very dark recess of my fathers attic. The quest was to find a box of Meccano which had been packed away since my childhood, green and red vintage with brass cheesehead bolts. I can confirm your 5/32" size and also as part of a long forgotten assembly I see that many of the bolts have been lock-nutted so that must have been my preferred method of 40 years ago. The bloody nuts still hurt my fingers when I tried to undo them as no spanner was to be found! I packed the box away again for the next 40 years although I suspect it won't be me that opens it next time.

Regards

Keith

Reply to
jontom_1uk

You mean the french have not modified something they never came up with? Shame their vehicle designers couldn't try the same philosophy!

Reply to
moray

In article , jontom snipped-for-privacy@hotmail.com writes

Yep, they are hard on the fingers. The 1960s nuts were IIRC all square, which made them marginally easier to do/undo with the fingers -but not lock-nutted ones of course! The spanners (two were supplied) were cheap stamped things with one end cranked to get into tight corners.

David

Reply to
David Littlewood

The USA "Erector" sets used 8-32 round head slotted screws and square nuts. I still have some of the screws and nuts in my "8-32" hardware drawer. These date from the 1930's and 40's.

Don Young

Reply to
Don Young

May be this helps:

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"Ken Wilson" schreef in bericht news:f60vfl$9hn$ snipped-for-privacy@aioe.org...

Reply to
PG1D/PA-11Ø12

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