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OFSO
10th Feb 2015, 09:49
Whilst drinking a coffee today and watching the attempts of my good friend Peter B. attempting to replace a bolt in an ice-maker obviously not designed for repair, Peter said "why is it that nuts or bolts always UNSCREW ? Is it something to do with the direction of the thread ? And if so shouldn't threads go the other way ? And equally importantly, do they also unscrew south of the equator or do nuts tighten in the Antipodes ?

Well ?

MagnusP
10th Feb 2015, 09:57
Well, you'd have to invert the Coriolis force on your torque wrench once you're in the south, but it should still work.

oldchina
10th Feb 2015, 09:58
Depends how cold it is

joy ride
10th Feb 2015, 10:06
I put a drop of Loctite 243 on my nuts, stops them heading south.

tony draper
10th Feb 2015, 10:08
I read somewhere that the sneaky Hun oft employed bolts and screws with the opposite thread to bamboozle our bomb disposal chaps.:uhoh:
The humble Nut and Bolt has a fascinating History.
The history of the bolt - Nord-Lock (http://www.nord-lock.com/bolted/the-history-of-the-bolt/)

Fareastdriver
10th Feb 2015, 10:32
Should you have possessed a BSA sports car you would have had LH wheel nuts one side and RH wheel nuts the other.

joy ride
10th Feb 2015, 10:34
Do you mean the lovely 3 wheelers? A friend had one in the 1980s, a bit like Morgan Fs

LGW Vulture
10th Feb 2015, 10:54
If this thread is any indication of what retirement does to you, then I'm either 1. working until the end comes or 2. booking a one-way ticket to Zurich........:uhoh::uhoh:

oxenos
10th Feb 2015, 10:55
If you have LH tread on one side of the car and RH on the other, what do they use on the central wheel on a 3-wheeler?

Fox3WheresMyBanana
10th Feb 2015, 11:05
Shouldn't this thread just be a PM to Nutloose? ;)

Shack37
10th Feb 2015, 11:10
Scandal in the laundry.

Nut screws washer and bolts.

Where´s me coat?

Ancient Mariner
10th Feb 2015, 11:48
Oxenos: If you have LH tread on one side of the car and RH on the other, what do they use on the central wheel on a 3-wheeler?

Double threads of course.
Per

http://i1339.photobucket.com/albums/o702/perebs/double%20threads_zpslj3xie18.jpg (http://s1339.photobucket.com/user/perebs/media/double%20threads_zpslj3xie18.jpg.html)

onetrack
10th Feb 2015, 12:06
One clever researcher by name of Gerhard Junkers discovered (in 1969) that the major reason for fasteners coming undone where vibration is a primary cause, is because of the transverse movement of the two mating surfaces.

http://www.boltscience.com/pages/Why_nuts_and_bolts_can_self-loosen.pdf

Junkers actually built a vibration test machine to test various type of fasteners, to test various methods of trying to stop fasteners from coming undone - and to test various grades of fastener strength - and fastener coatings as well.

The results are quite interesting - and the test machine proved that in many cases, locking spring washers are next to useless as far as stopping fasteners from coming undone, goes.
I proved this to myself many years on earthmoving machines (where vibration and fastener loosening are major problems - by eliminating spring washers (that usually broke, anyway), and by just using hardened washers and a satisfactory torque level, which provided good tension on the joint.

Once I did that, loose fasteners were reduced to a bare minimum.

G-CPTN
10th Feb 2015, 12:07
In the late 1960s I bought a pre-War MG.
I decided to fit new bolts when I renewed the (cork) clutch plate.
None of my spare bolts (I had a very large box inherited from my grandfather) would fit, so I took one along to 'Bolts R Us' on a nearby trading estate.
He got out the calipers and measured the pitch and said "What thread has 25½ threads per inch?"
Eventually the penny dropped and he produced metric bolts which had the correct thread.
The MG engine was, in fact, a Hotchkiss design licence-built by MG - with Imperial heads on bolts with metric threads.
Once you know this the rest is simple . . .

Blacksheep
10th Feb 2015, 12:29
Do the nut up tight, drill a hole through the nut and bolt, and fit a split pin.
Simples.

For domestic ice makers, coffee pots etc, you'll need a dremel and a set of super-fine drill bits of course, but once you've finished they'll never come loose.

Imperial heads on bolts BSF or Whitworth? ;)

Ancient Mariner
10th Feb 2015, 12:36
Methinks it might be somewhat overkill for coffee pots and ice makers, but if belt and braces is your normal modus operandi, by all means. ;)
Here are some other suggestions, many which I have used professionally through the years.
Per

Screw Locking and Retaining Methods (http://www.roymech.co.uk/Useful_Tables/Screws/Locking.html)

G-CPTN
10th Feb 2015, 12:43
However, to save the British the cost of new spanners, the nuts and bolts had Whitworth heads.
From:- HotchkissBull (http://www.bullnose.org.uk/HotchkissBull.htm)

Allan Lupton
10th Feb 2015, 13:59
It wasn't just the Hotchkiss motors, as the factory became Morris's engine works and produced many types of non-Hotchkiss designs.
Therefore all sorts of Morris-based vehicles had engines with the Whit-headed metric fasteners including the engine of G-CPTN's MG which I expect was a TA. I'm not sure when the system was changed, but the post-war XPAG engine in the MG TC was still like that - and it probably was when used in the TD, TF and Y-types.

rgbrock1
10th Feb 2015, 14:06
This winter so far my nuts have been very tight. Disgustingly snowy and cold. :}

OFSO
10th Feb 2015, 14:14
you'll need a dremel

Nobody needs one of those cheap Mexican-built things - Buy a German-made Proxxon.....

However: thanks all for advice. My friend Peter will be glad of it......

dazdaz1
10th Feb 2015, 14:29
I recall back in the 70s my Ford Transit van, f/n/s nuts were anti clock o/s clockwise.

toffeez
10th Feb 2015, 14:32
Put them on red hot charcoal for a minute or two.

MagnusP
10th Feb 2015, 14:52
BSF or Whitworth?

Somewhere in a drawer in my garage or shed, I still have my old Zeus tables (remember the thing that fitted in your dustcoat pocket) from when there were just the two engineers looking after the UK Schmidt Telescope and we had to cover electronics, electrics, optics, hydraulics and mechanical engineering problems. BSF, Whitworth, metric, AF, all at yer fingertips.

I think the UKST was built by Grubb Parsons in the FSL's bailiwick.

rgbrock1
10th Feb 2015, 14:52
toffeez:

Now there's an idea. Roasted nuts over a fire. :ok::}:eek::E

Akrotiri71
10th Feb 2015, 15:00
My Zeus book is the first thing to go into my overall's pocket at start of shift.

:ok:

Nord-Lock washers. :ok:

ian16th
10th Feb 2015, 15:00
Do the nut up tight, drill a hole through the nut and bolt, and fit a split pin.
Simples.

For decades the RAF got by with locking wire.

It rips denims and working blue's much better than a split pin:cool:

tony draper
10th Feb 2015, 16:18
A tip, never re use those nylock nuts once they have been removed chuck em in the bin and fit new uns,I know someone who did reuse em,one shall not elaborate.
:uhoh:

Flash2001
10th Feb 2015, 16:18
AKA the Simmons nut in days of yore. OBTW locking wire, no matter how skillfully applied, does not keep a nut or screw tight. It does prevent the loosened article from unscrewing and falling into the works.

After an excellent landing etc...

superq7
10th Feb 2015, 16:21
Aks I've still got mine ! and some Vanmars dollys etc from my aircraft fitting time at Filton.

http://i58.tinypic.com/1ql30l.jpg

Krystal n chips
10th Feb 2015, 17:22
Might as well mention oxygen replen. here. A LH thread to prevent, in theory, other connections being attached and vice versa.

I seem to recall that human nature managed to achieve this however.

A quick glance at a thread will tell you straight away as to which direction.

As threads go, nothing compared to ( yet another ) "wonderful" British design. The Avery hydraulic connection.

Clearly designed by a former employee of "Wilkinson Sword", you could slice the skin off your hands with no effort at all, it also had to ability to trap the unwary by appearing to start perfectly.....until, after a few turns and when the equally useless spanner was needed, it suddenly became "rather stiff".....or cross-threaded if you prefer.

Fareastdriver
10th Feb 2015, 18:23
One of my ground instructors was detached to the Ghanain Air Force in the sixties. Locknuts with a spot of paint on them were those that were on their second time around.

John Hill
10th Feb 2015, 18:31
A tip, never re use those nylock nuts once they have been removed chuck em in the bin and fit new uns....

But if you insist on re using a nylock nut first put in a solid surface and wack the top with a hammer. That will squeeze the nylon and restore the original pressure.

Flybiker7000
10th Feb 2015, 18:59
The different direction of threads for wheelbolts are only the case for center/hub nuts as the rotating of the wheel will tighten the thread with the same direction as the (normal) rotation.
The ansver for the clever 3-wheeler question will likevise depend on from wich side the center-nut (in case of use) was placed!

The Nord-lock history lesson comes easy past the fact that Withworth became the standard of the english railroads by rationel needs, and by the following widely spread It became the choise when a national standard had to be set a pair of decades later - This being in the middle of 19th century.

'Landsoldaten', the primary monument of my OY-hometown is piece-casted in England and rised in 1858. As piececasted the single parts are bolted together and a couple of years ago an internal inspection showed surprisingly hard galvanic corrosion between the bronze pieces and iron bolts.
The following restoration showed that only the two main bolts, spanning the figure to the base, was withworth standard whilst the rest was (quote:) 'mixed bonbons'!
Square nuts and boltheads, by the way.

tony draper
10th Feb 2015, 19:44
Here's a wopper,but no doubt there are larger one's somewhere,them Victorians didn't do things in half sizes.:)
http://i11.photobucket.com/albums/a194/Deaddogbay/Deaddogbay002/200px-One-hundred_ninty-three_pound_nut_and_bolt_one_of_16_used_to_join_sections_of_ the_generator_shaft_of_a_75000_kW_genera_zpsysg7hqb6.jpg (http://s11.photobucket.com/user/Deaddogbay/media/Deaddogbay002/200px-One-hundred_ninty-three_pound_nut_and_bolt_one_of_16_used_to_join_sections_of_ the_generator_shaft_of_a_75000_kW_genera_zpsysg7hqb6.jpg.htm l)

ShyTorque
10th Feb 2015, 20:22
The two best tools I ever bought were adjustable spanners. One is metric, the other imperial.

ExSp33db1rd
10th Feb 2015, 20:32
Depends how cold it isor how pretty she is

The two best tools I ever bought were adjustable spanners. One is metric, the other imperial. ??? !

The best spanner I ever bought has a sort of Parrot Beak head that tightens on to the bottom jaw as pressure is brought to bear on the handle, BSF, Whitworth, Metric, Galvanised Baptist etc. it automatically adjusts to the size it is presented with, just turn it upside down to unscrew. Akcherly - I bought two, one for very large nuts and one for very small nuts.

What really enrages me is having finally got to the screw head with a straight and Phillips head screwdriver handy, I then need one of those square ended jobs - which I don't have, I have to stop, climb up or down from the location, find my tool box, scrabble around for a box of assorted heads to fit a T handle holder etc. etc. ... well, you know.

G-CPTN
10th Feb 2015, 20:43
In my working life as a vehicle engineer (not a mechanic - design and test engineer) I was consulting our metallurgist, when he related the following anecdote.

He was a member of a standards committee related to 'threads'.

A modification to some standard (or new) thread form had been proposed, actually it was the ratio of the head dimensions IIRC.
Most of the committee members were in agreement until one member interjected that the proposal wasn't acceptable to his industry.
"The heads won't be climbable." he said.

Puzzled by this remark, my colleague had imagined some inadvertent 'welding' when tightening the bolts, but he demanded an explanation.

"The heads won't be climbable." repeated the complainant.

"Whatever do you mean?" replied the metallurgist. "Just what industry do you represent?"

"We build offshore oil rigs, and the workers use the heads of the bolts as footholds when they climb the structure during the assembly stage."

So there you had a conflict between the requirements of a vehicle manufacturer and an oil-rig manufacturer - a question of scale.

Flash2001
10th Feb 2015, 20:57
Flybi

Mopar (Dodge Chrysler etc.) products up until 1970 or so had LH threads on the left side of normal star pattern (not on centre) wheel fasteners. Experimental work in the 50s and 60s had shown that untorqued RH fasteners on the left side of the vehicle tended to loosen whereas on the RH side of the vehicle they tightened with with operation. Correctly tightened RH fasteners gave no problems on either side.

After an excellent landing etc...

onetrack
10th Feb 2015, 22:25
Re the Bolt Science poster, does the zinc plated bolt on the bottom right have a LH thread?It does appear to be LH thread. Either the image was reversed during the process of producing the PDF document - or they slipped it in, just to see how sharp, the average document reader was!

Fastener variations and tools needed? Don't get me started on the screw head varieties.
One thinks one is attacking a Phillips head screw - then one finds it's a PoziDrive - no hang on, it's a Quadrex! - wait up, it's a Frearson! - no, it's not, it's a JIS! Darn, it must be a BNAE! Wait, I've got it! - it's a Lotus head drive!! :{ :}

When a Phillips is not a Phillips (http://www.instructables.com/id/When-a-Phillips-is-not-a-Phillips/)

cattletruck
11th Feb 2015, 09:28
I learnt a simple technique to keep your nuts from ever falling off from an old school plumber.

Before you fit your nut grab a vice-grips and crimp the thread of the bolt near the point where the nut will end up when tight.

You don't need no spring washer, nylon, loctite, etc.

Akrotiri71
11th Feb 2015, 09:57
Three pages on nuts and bolts. Excellent, what a fastenating thread.

Hat, coat.....

Mechta
11th Feb 2015, 12:20
If you absolutely have to reuse Nyloc nuts, boil them in water for a few minutes. Nylon absorbs about 50% of its weight of water. This returns the locking ring to more or less its original shape and restores most of its locking performance. Replace the reused Nylocs at the earliest opportunity. I used to do this on a regular basis after flying my hang glider on coastal sites, as a full strip down and wash (of the glider) was part of the post flight maintenance procedure.

With regard to mixed standards; any model fliers here who have Japanese glowplug engines will be familiar with the 10mm across flats propeller nut with a 1/4 UNF thread. Expensive to replace unless you make them yourself!

This poster, or something very similar, was on the wall of our apprentice training workshop:
http://imageshack.com/a/img631/2372/BY8vtL.jpg

joy ride
11th Feb 2015, 12:39
I love that poster, every possible botch !

Retaining Compound (e.g. Loctite 603) is remarkable stuff for holding a tight-fitting shaft in a cylinder (or a gear on a shaft. It crystalises to form multiple "pins" digging into both bodies, and it takes brute force to break the components apart. Once I incorrectly Retained a 6 mm shaft in a 2" cube of Perspex (Plexiglass), when I tried to twist and remove it the Perspex block was virtually excoriated, leaving about 10 mm of jagged Perspex still firmly pinned to the shaft.

Kitbag
11th Feb 2015, 15:24
I have to say that the received wisdom to replace a Nyloc nut after every use is wrong (and I believed it for many years myself). A few years ago I witnessed proof testing where after 50 uses the rundown torque of a Nyloc not only met the BS requirement for new locknuts, but was somewhat better than equivalent all-metal types. The tests were being carried out because our American chums do not get shot of their nylocs after every use (they were quite common on the P&W Twin Wasp series) and British operators wanted to know why. The correct method with a locknut as you all know is to measure the rundown torque with a torque wrench. If it meets the requirement it can be used again.

Fox3WheresMyBanana
11th Feb 2015, 15:41
I can assure you that the previous owner of my yacht, who had removed the rudders each winter for revarnishing but, as I discovered, re-used the same nylock nuts, was the subject of a few choice words* when I had to reattach a rudder at night in a force 6 off Fuerteventura, singlehanded.


*some of which had more than four letters, but only because I've had a classical education.

Molemot
11th Feb 2015, 15:56
On my old Alfa GTV, the left hand side had left hand threads; so,when I came to deal with a second hand Luton Transit in later years, I was careful to check first. Yes.... Left hand side had left hand threads, and right hand side had right hand threads...and since it was the RH inner rear wheel I wanted to fit a new tyre to, that would be a normal RH thread. So Moley happily gets out the sockets and bars....much heaving, but no movement. Hmmmm. Checked the Book again....yes, RH side, RH threads. Made sure I was turning the nut anticlockwise...Tried several times...still no joy, even with the socket extension supported on an axle stand and using a length of scaffold tube on the socket bar. Even standing on the end of the scaffold tube...nothing.

Tried the pneumatic impact gun. The wheel nuts laughed at it. ALL RIGHT, time for re-inforcements!! So I phoned a friend who is involved in the preservation of old fire appliances...and he arrived with his 3/4" drive sockets, and we set to. Ten minutes later, still nothing. At this point we decided that Something Was Not Right, and got out the magnifying glass. Scrutinising the one and a half threads sticking out beyond the nut, we decided that it was actually a LEFT hand thread....and then the nuts finally came off!!

Seems some previous mechanic had taken the rear axle apart...and reassembled it with the half shafts in the wrong sides!!!

Fox3WheresMyBanana
11th Feb 2015, 16:07
I used to know an Italian mechanic who'd trained at the Alfa factory. He was excellent, but from some of his stories your problem may have originated at the build stage!

Kitbag
11th Feb 2015, 16:35
F3WMB thinking about your problem I wonder what size nuts you were using; the tests I saw were for fairly small (up to about 3/8" dia thread), if yours were much larger it would be reasonable to assume that the friction effect would be less, although I couldn't guess at how much less. Equally it is possible the previous owner just reused the same nuts with checking they would lock?

Fox3WheresMyBanana
11th Feb 2015, 17:09
Both I believe. I think they were 1/2" bolts, and they had the same patina as other bolts I knew to be 5 years old at least, so they'd probably been reused 5 times.

Fantome
11th Feb 2015, 17:09
If this thread is any indication of what retirement does to you, then I'm either 1. working until the end comes or 2. booking a one-way ticket to Zurich....

an applaudable pun .. . . . yes


but other remedies are nearer at hand




http://davidmoody.net/wp-content/uploads/Banging-your-head.jpg (http://davidmoody.net/2014/04/18/hitting-head-brick-wall/)

joy ride
11th Feb 2015, 18:50
I personally avoid re-using Nylocks, but if that evidence is correct then I have wasted quite a few!

However, my guess is that they used the same new bolts for the tests, but a bolt in service life can change: if the threads on the bolts develop any imperfections, deformations, surface rust, lifting chrome plating etc., then this might well wear down the nylon ring and make the Nylock useless. Labs don't always replicate the real world! A Marine environment can damage even some grades of stainless steel eventually.

OFSO
11th Feb 2015, 19:59
But for a solution which fits everything:

TORK-GRIP, The Ultimate Torque Wrench For The Bicyclist (http://sheldonbrown.com/tork-grip.html)

Fox3WheresMyBanana
11th Feb 2015, 20:42
"'ere, wot's FT mean, 'Arry?"

"F#ckin' Tight!"

G-CPTN
11th Feb 2015, 20:55
We had a splurge of wheel-stud failures on truck wheels.
I approached the tyre-bay fitter (a big sturdy chap of, perhaps, 22 or 24 stone) and enquired what torque he was setting the wheelnuts.

"Tight, plus half a turn" came the reply, so I asked him to show me.

Fred produced a scaffolding pole which had been cut, bent, and welded by Wally (the weld) to reinforce the standard wheelnut spanner which was now deeply embedded within the scaffolding pole such that only the 'nut' part protruded.

Fred showed me how he turned the scaffolding pole (about six foot long) until the nut was 'tight' then applied his weight to extract 'half a turn' from the wheelnut.

Torque wrench? I don't believe that Fred knew that such things existed - or, at least, if he did then it was what engine-builders used on cylinder-head bolts to avoid snapping the studs.

His 'problem' was getting wheelnuts 'tight' so that they didn't loosen and fall off.
To be fair, I doubt that Fred (even with his scaffolding pole spanner) could have exerted enough torque to snap a wheelstud when he tightened the nut.

cockney steve
11th Feb 2015, 22:13
To be fair, I doubt that Fred (even with his scaffolding pole spanner) could have exerted enough torque to snap a wheelstud when he tightened the nut. No, but they would have been tensioned like a violin-string....then add the dynamic loads of a lorry, accelerating, braking and , more especially, cornering and it's not hard to understand why a stud would fatigue and fracture.

The plastic pointer-things observed on the wheelnuts of lorries and buses are a visual check that all the nuts are there and they haven't moved.

with massive advances in chassis design and tyre technology, wheel retention is becoming a limiting factor......adding more studs and nuts is not the answer because that leaves less metal between them , so fatigue cracks start occuring.

next time you change a car wheel and curse a stuck wheel, reflect on the fact that tight spigot is taking a lot of stress ( kick the tyre inwards , then repeat, diametrically opposite.....you will rock the wheel loose!)

Flybiker7000
11th Feb 2015, 22:39
Though marginal advance I think that Star-patterned/multiple wheelbolts with lh tread mostly was a reminiscence of the hub-nuts :-/
When rh treaded wheelbolts prooved reliable was the production getting more streamlined by avoiding two tread-directions to control!

Krystal n chips
12th Feb 2015, 05:41
I approached the tyre-bay fitter (a big sturdy chap of, perhaps, 22 or 24 stone) and enquired what torque he was setting the wheelnuts.

"Tight, plus half a turn" came the reply, so I asked him to show me.


I think I've found a close relative. Went to a local tyre garage about 4 years ago. Approached by the son, who, being charitable, was unlikely to make a career in sales. He slowly explained that "Mitchelin" wuz a very good brand...one smiled and politely declined this sales pitch. Went into the workshop and saw the father, same physique as above, happily fitting the wheel nuts to a poor little F.Focus....same technique / home made tool, not an air gun or torque wrench in sight, if indeed he actually had one.

"Made my excuses and left" as a now defunct rag used to say.

To be fair, they also did a lot of agricultural tyres...so it's easy to see where the confusion may have arisen.

As for dynamic loads, the 737 brake units were originally held in place by 3 bolts....until a few parted company with the axle. Thereafter, the mod. was to increase the number slightly.....to 11.

Personally, I blame to drivers for heavy braking and "firm" landings....Basil...;)

The Jaguar brake unit was attached with....one circlip. Work out the dynamic loads on that if you wish.

bcgallacher
12th Feb 2015, 06:49
Boeing got smart after the 737 - the 747 brake units are retained solely by the wheel assembly. The only nut to remove is from the torque arm and it is split pinned (cotter pinned for our American cousins)

ExSp33db1rd
12th Feb 2015, 07:00
It's all very well tyre purveyors tightening the wheels with their homemade, or even air hose pneumatic, spanners once they have changed the tyre, but I have to untighten them with a puny wheel brace, at the side of the road, at night, in the rain, without a torch. ( the battery has always run down, so now I have one of those dynamo type torches, but this needs a few more squeezes of the handle at the wrong moment. Murphy is always with us )

If I can I tell them to only tighten gently, then I follow them around with my puny wheel brace ( and puny, 80 yr.old body) and complete the tightening process. Haven't had a wheel fall off yet.

Off Thread ( to coin a phrase ) - Friend lent his girl friend his car, she got a puncture and stood by the side of the car in obligatory Damsel In Distress pose, and right on cue a Knight In Shining Armour stopped and changed the wheel for her. As he tightened the spare in place, she picked up the original wheel and said "well we don't need that anymore, do we "? and promptly pushed it down a steep embankment into some Blackberry bushes at the side of the M.1. True story, but despite that still ended up marrying my mate.

Ancient Mariner
12th Feb 2015, 07:13
I change wheels twice a year on our two cars, not a big job and I always use the tool that comes with the car, which also coincidentally is the one needed if you have a mishap out in the sticks.
Come to think of it, my wife's Merc doesn't have a tool, or a spare tire, but a compressor and a can with some stuff in it. Tough on her.
Per

Stanwell
12th Feb 2015, 08:30
AM,
That's all very well - until she splits a sidewall on a kerb or something.
What's she do then?

Also, the tyre 'technicians' do not want to know about repairing a puncture once that black gunk's been squirted into the tyre.
But... they'll happily sell you a brand new tyre - of which, fortunately, they just happen to have one in stock. (It's your lucky day!)

We've gotta keep the economy going, y'know.

Ancient Mariner
12th Feb 2015, 08:35
Stanwell:AM,
That's all very well - until she splits a sidewall on a kerb or something.
What's she do then?
Entirely up to her, hopefully she'll buy another car since I positively hate the A.
Per

airship
12th Feb 2015, 16:12
My standard 0-6" (0-150mm) vernier calipers plus a set of metric, UNC/UNF, BSW and BSF thread gauges (obtained the last BSF one especially for old British-made motorbikes) usually get me out of trouble when it comes to nuts and bolts.

However I did buy one of these back in 2012 especially for mostly high-pressure hydraulic applications which has been quite useful also:

http://img-europe.electrocomponents.com/largeimages/F3666221-02.jpg

Parker Hydraulic Thread Indentification Kit #MIK-1 (RS Stock No. 366-6221 (http://uk.rs-online.com/web/p/hydraulic-thread-identification-kits/3666221/)) £36.30 exc. VAT inc. delivery. It's the manual which comes with it which is most useful though, explaining the procedure of identification relatively straight-forwardly. :ok:

G-CPTN
12th Feb 2015, 16:22
Wheelnut spanners supplied by vehicle manufacturers may appear puny, but they are calculated to apply the necessary tightening torque required for safe wheel retension - which explains why they bend when trying to undo wheelnuts that have been overtightened by air-guns (though, to be fair, my local KwikFit always uses a torque wrench and offers a free re-torquing service after a short period of normal driving).

Fox3WheresMyBanana
12th Feb 2015, 16:35
These are the babies
Torque limiting extension bars for air guns - dead quick and accurate - I just double-check one with a torque wrench every so often, but they're always spot on.
http://images11.palcdn.com/hlr-system/WebPhotos/84/848/8485/8485039.jpg?_v=5a94e708-b43a-47fc-b9d2-56110847a5a6

Flash2001
12th Feb 2015, 16:48
Old British motorcycles didn't have a great many BSF threads. They had a lot of BSWs (Mostly in castings) and a lot of CEIs (Mainly on screws and nuts) and, of course, a few BAs thrown in to confuse.

After an excellent landing etc...

Fishtailed
14th Feb 2015, 00:26
Nuts and Bolts- great thread.


G-CPTN


"What thread has 25½ threads per inch?"
Imperial heads on bolts with metric threads.


Good old British Association- 0BA


Flash2001-


My 1975 Trident had 5 thread types- metric, BSF, Unified, Cycle and BA

ian16th
14th Feb 2015, 08:50
In the 50's most RAF radar & wireless kit was assembled with BA nuts & bolts.

cockney steve
14th Feb 2015, 09:17
^^^^^^ maybe because BA was the "standard" electrical thread ?

Whitworth, a relatively coarse thread, tended to be for low-load and exposed stuff, -structural steelwork on metal framed buildings, gates, fences, stuff that needed undoing and refastening , especially where castings were concerned.

BSF...the universal engineering thread (British Standard Fine)

Spanner sizes were the same as the next-smaller BSW size, IE 1/4 Whit was the same head /nut size A/F (across flats) as 5/16 BSF

Both , largely succeeded by the American Unified National Coarse and U N F.

-so we all bought new "A/F" (Across flats) spanners and sockets.....only for these to be superseded by the Metric Coarse and Metric fine system. which , again is littered with "oddball" thread pitches and head-size to shank ratios!

Yamagata ken
14th Feb 2015, 10:28
I was slightly stymied refurbing an approx. 40yo industrial mixer in the memsahib's factory. I was trying to replace the tired old fastenings with new metric when I realised that things weren't going well. I whipped out the trusty vernier calipers and the numbers made no sense. A quick check on the innertubes showed them to be BSF with metric heads.

Not something you come across every day. I was clued in enough to realise that new metric fastenings weren't going to work before causing any thread damage.

Allan Lupton
14th Feb 2015, 11:48
Further to what I wrote before:
It wasn't just the Hotchkiss motors, as the factory became Morris's engine works and produced many types of non-Hotchkiss designs.
Therefore all sorts of Morris-based vehicles had engines with the Whit-headed metric fasteners including the engine of G-CPTN's MG which I expect was a TA. I'm not sure when the system was changed, but the post-war XPAG engine in the MG TC was still like that - and it probably was when used in the TD, TF and Y-types.

There was another trap for the unwary when dealing with pre-Great War FIATs.
They must have got their threading machines from Whitworth's as many of the fasteners were Whitworth threaded with metric heads (so the Italians didn't need another set of spanners either).

It was my ambition to construct a Morris-engined FIAT-chassised special just to be able to quote the well-known playwright "Confusion now hath made his masterpiece"

Yamagata ken
14th Feb 2015, 12:41
Whit headed metric and metric headed Whit (OK, BSF). What a tangled web we weave....

Take care out there, especially when dealing with old stuff.

Serious question. Were the Packard Merlins BSW/BSF or UNC/UNF?

Windy Militant
14th Feb 2015, 12:59
I don't know what Packard Merlins were, but the Gypsy major on the Auster I had a share in had ANF, ANC, BSF, BA Metric and Bicycle thread on it. It also had a lot of 64th size nuts, try getting hold of spanners for those! Six wall drive metrinch comes in very handy at times like that!

Fords had metric bolts with A/F heads and Unified bolts with metric heads when they went metric in the 1970s.

om15
14th Feb 2015, 13:27
Serious question. Were the Packard Merlins BSW/BSF or UNC/UNF?

I have a set of Blue Point BSF ring spanners that I used for years on RR Darts, they are very slender high quality matt finish.
The retiring bloke that gave them to me 40 years ago aquired them from a lend lease Packard Merlin tool kit that was supplied with each engine.
So it does look like the engines were BSF.

bcgallacher
14th Feb 2015, 13:58
You must have had a very strange Gypsy Major as the engine used DH metric threads which were unique except for 6 and 7 mm threads. The reason for the metric threads was that the engine was basically half a Renault V 8 of WW 1 vintage.

Windy Militant
14th Feb 2015, 16:45
You must have had a very strange Gypsy Major
Dunno but every bit you took off needed three spanners at least. There seemed to be at least two different thread sizes which had two different head sizes on the casings and the bolts all seemed to have heads a different size to the nut that was on it, except the one where they were both the same size! :confused: Which meant you never had the right sized spanner for the one you were trying to undo! :ugh:

bcgallacher
14th Feb 2015, 20:04
The hex headed bolts and nuts on the gypsy required BSF, Whitworth and BA wrenches and sockets.The threads on the fasteners were metric however.I still have the universal jointed T handled socket for removing manifold nuts that I made as a student in 1963. The crankcase was not very rigid but the crankshaft made up for that - it was a beautifully machined all over work of art. I flew behind a Gypsy in a Tiger Moth a few weeks ago - very emotional recalling the sounds and smell of the thing after 50 years or so and 60 years after my last flight in a Tiger.

radeng
15th Feb 2015, 12:35
BA is actually a metric thread, and was introduced by Thrury in Switzerland in the 1800s for the horological industry. It originally went down to number 27. Unlike unified, metric (both 60 degree thread angle) and Whitworth form (55 degree) threads, its 47.5 degree thread angle makes it appreciably stronger: that was needed because the very small sizes used in horology were pushing even hardened steel to its limits. So size for size, it is stronger than metric, BSW or unified. I seem to recall that it was after WW2 that a British Standard for BA threads appeared in imperial units.

It is also the only logical thread in that the thread pitch of each size is 0.9 of the size below, so 0BA is 1mm pitch, 1 BA is 0.9mm, 2BA is 0.81mm and so on. BSW hex heads were reduced in size during WW2 to save steel, BSW bolts from about 1942 will have the same hexagon size as the equivalent BSF which always had smaller heads by one size.

wings folded
15th Feb 2015, 12:44
BA is actually a metric thread, and was introduced by Thrury in Switzerland in the 1800s for the horological industry. It originally went down to number 27. Unlike unified, metric (both 60 degree thread angle) and Whitworth form (55 degree) threads, its 47.5 degree thread angle makes it appreciably stronger: that was needed because the very small sizes used in horology were pushing even hardened steel to its limits. So size for size, it is stronger than metric, BSW or unified. I seem to recall that it was after WW2 that a British Standard for BA threads appeared in imperial units.

It is also the only logical thread in that the thread pitch of each size is 0.9 of the size below, so 0BA is 1mm pitch, 1 BA is 0.9mm, 2BA is 0.81mm and so on. BSW hex heads were reduced in size during WW2 to save steel, BSW bolts from about 1942 will have the same hexagon size as the equivalent BSF which always had smaller heads by one size.

One has to tug one's forelock at such erudition. Still find that a Manchester screwdriver loosens or wrecks most bolts...

Windy Militant
15th Feb 2015, 13:35
BA is actually a metric thread That explains why, when my mate lost a head nut from his moped a standard 10mm metric nut wouldn't fit but a 0BA would, must have been a metric fine thread on the Stud!

bcgallacher a Gypsy Major is indeed the finest mode of propulsion for a gentlemans aerial conveyance!:ok:

Flybiker7000
15th Feb 2015, 14:28
@Flash2001:
BSA hung on their bicycle-past by the favor of the BSC-thread and differed to the rest of the british motorcycle industry at this area!

Flash2001
15th Feb 2015, 14:32
FB 7000

My Nortons are largely BSW (Castings) and CEI.

After an excellent landing etc...

Molemot
15th Feb 2015, 16:45
Back in the late 60s, when I was rebuilding an MG TC, I needed a load of assorted threaded fasteners. I therefore repaired to the wonderfully named Allscrews of Hammersmith, with my list. Whilst waiting my eyes chanced upon a poster on the wall. It depicted a Land Rover in the middle of the desert. Standing by it was it's British driver, pointing sternly at the horizon, from whence a line of footprints could be seen, ending at the LandRover. Slinking away along the line of footprints was an Arab. The caption was "Go back, Kassim!!! I said a WHITWORTH thread...."

Fishtailed
15th Feb 2015, 22:29
"Somewhere in a drawer in my garage or shed, I still have my old Zeus tables"
I managed to find the first year training school one we were issued with in 1968. The back cover is an AH&N dream:). I dread to admit there's three or four companies I don't recognise:O Does anyone know them all?

Sorry about the thread drift;)

http://i49.photobucket.com/albums/f280/fishtailed/Scan_Pic0044_zpsd5hx1y48.jpg (http://s49.photobucket.com/user/fishtailed/media/Scan_Pic0044_zpsd5hx1y48.jpg.html)

ian16th
16th Feb 2015, 09:52
http://i818.photobucket.com/albums/zz108/ian16th/FRL.jpg

Flight Refueling Ltd, now Cobham PLC

As used on 214 Sqdn Valiant's.

It was at the time the only case of a registered trademark being used by an RAF squadron.

It was used with the Nightjar from the squadron badge. Visible here on the tail fin of WZ390.
http://i818.photobucket.com/albums/zz108/ian16th/WZ390UnderTow.jpg

MagnusP
16th Feb 2015, 09:55
Nice piccy, ian16th. Interesting pointy things in the background!

ian16th
16th Feb 2015, 10:55
Magnus,

To paraphrase some old Chinaman.

They were 'interesting times' to be on the V-Force.

Fishtailed
16th Feb 2015, 22:49
BA is actually a metric thread - It originally went down to number 27.

Wow, 27BA, my table only goes to 23, and that's 11 thou O/D, so 27 must be around 7 or 8 thou diameter with a 2 thou pitch:eek: I have a 16BA tap and die set and when I look at them I wonder how they were made, but 27BA:{

BSW hex heads were reduced in size during WW2 to save steel, BSW bolts from about 1942 will have the same hexagon size as the equivalent BSF which always had smaller heads by one size.

I had heard that the bolt heads had been made to a common size to reduce the number of spanners required to be carried in the field, but that saves steel aswell.

radeng
17th Feb 2015, 11:09
Metric threads are, in general, too fine for aluminium castings: one is much better off with BSW or UNF. I am told that there is a Japanese national standard for a coarser metric thread..

At one time, it was said that the USAF would only go over to metric threads if it didn't cost any more - the most sensible statement on the subject! For my own stuff, I stick to BA, although I have metric taps and dies - and some unified ones, too.

I don't think anything smaller than 16BA is available now: personally, I have worries even when using a 10 BA tap! Several of the books intended for model engineers have a lot of information on all these threads. Here, we have three sets of Zeus tables of various ages - one of them being the property of mrs radeng from her university sandwich course days - and an equivalent little book from pre Zeus days which is not oil and grease proof. Plus my grandfather's 1925 Machinery's Handbook......I'm told that is quite valuable as a collector's item, but I find it valuable as a reference book for various things.