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goldstar31

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How many people use the BA hardware in their engines? Wouldn't it be easier, in terms of standardisation, to use the closest metric or imperial thread form?
Isn't it the matter of personal preference and having a drawer FULL of assorted taps and dies collected over the years------AND the wherewithal AND the ability to sharpen them?

Years ago, I built a Quorn. The stones are held in arbours which are held on to a high speed spindle- of exactly ONE inch but everything is held on with 1/4 BSF AND 2BA.
Why change-- and negate ALL this work?

But I went to a show at Doncaster and a firm was flogging Myford Tee nuts for less than I could make them and I bought a heap- plus a baby rotary table(. digressing). There was something wrong, the 1/4 BSF studding wouldn't fit. It turned out for them to be tapped M6.

Somehow, I have a very cockeyed 'modern' Myford Super 7-- which cost the earth-- and is in Imperial Measurement but is probably held together with Metric fasteners.

Answer therefore is :-

As experience widens- and mine has been playing with mechanical things for perhaps 87 years now- who bloody cares?
For information, REAL locomotives were held together- with the nuts and bolts which were the ones which someone had obtained.
But, but the British Lords of the Admiralty in their infinitive wisdom made nut heads so big that the brawny sailor boys- couldn't twist the heads off.
Come WW2- to save on metal- the heads of bolts--were reduced in size.

Laughingly, I was about all these changes- like car engines with holding down studds with one end BSF and the other UNF. And thev darling Japanese not only copied all this- but drilled the cylinder heads-- to match the pre-War 'British A Series heads and blocks.
Err, next question?????
 

goldstar31

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Old age has crept up on me- but with tongue in cheek, British Association threads have English Whitworth form --- but are Metric in dimension.
What could be better--------or worse? And they are neither 55 degrees--- nor 60.

I've got a cousin in Tumbarumba in NSW--- and he thinks I'm mad.

Enjoy your little engine. I had one-- I loved it as one does when one is SEVEN.;)
 

BaronJ

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Isn't it the matter of personal preference and having a drawer FULL of assorted taps and dies collected over the years------AND the wherewithal AND the ability to sharpen them?

Years ago, I built a Quorn. The stones are held in arbors which are held on to a high speed spindle- of exactly ONE inch but everything is held on with 1/4 BSF AND 2BA.
Why change-- and negate ALL this work?

But I went to a show at Doncaster and a firm was flogging Myford Tee nuts for less than I could make them and I bought a heap- plus a baby rotary table(. digressing). There was something wrong, the 1/4 BSF studding wouldn't fit. It turned out for them to be tapped M6.

Somehow, I have a very cockeyed 'modern' Myford Super 7-- which cost the earth-- and is in Imperial Measurement but is probably held together with Metric fasteners.

Answer therefore is :-

As experience widens- and mine has been playing with mechanical things for perhaps 87 years now- who bloody cares?
For information, REAL locomotives were held together- with the nuts and bolts which were the ones which someone had obtained.
But, but the British Lords of the Admiralty in their infinitive wisdom made nut heads so big that the brawny sailor boys- couldn't twist the heads off.
Come WW2- to save on metal- the heads of bolts--were reduced in size.

Laughingly, I was about all these changes- like car engines with holding down studs with one end BSF and the other UNF. And the darling Japanese not only copied all this- but drilled the cylinder heads-- to match the pre-War 'British A Series heads and blocks.
Err, next question?????
A lot of model engineers use 47.5 degree BA threads, they also scale better on models.
 

goldstar31

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Now I hope that we have got 'B- lppdy A-wful threads an airing. Thanks John B!


So what about ME or Model Engineering threads of 32 and 40( and perhaps 72????

I'm currently( ouch) playing about with a hybrid tool and cutter grinder kit--- but it calls for that lovely 1/4" 40TPI thread that works as a measuring. thread- with 25 divisions and reading thousands?


And then there is 3/8th x 20TPI( I think) BSF. Got studding which works on my Stent tool and cutter grinder for the vertical or is it vertigo slide.

It ALL keeps what is left of the grey matter of ancient model engineers thoroughly active.

So I've cut the 4 lawns and back to boring ( in more ways than one) a 5/16th hole in a couple of 1" round and threading M5. No, 'm not to blame- I'm merely following the blue print which is black on white paper!:eek:
 

ZebDog

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Here in the U.K metric is the standard since we changed from imperial back in the 70s although imperial is still available metric taps and die are a little cheaper and the nuts and bolts are widely available in your local D.I.Y store I have 6 engines all built using 3 or 4mm bolts.
 

Charles Lamont

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I have, and like to have, the choice. Screwcut threads are nearly always imperial because my lathe has a 1/8" pitch leadscrew, and is built with BSF fasteners. My milling machine is UNC, unfortunately. Most tooling I have made in the last 20 years or so has metric fasteners. My current model engine project uses BA. It was designed to use 6BA threads, and neither M2.5 nor M3 would be as good. Horses for courses.
 

deverett

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I'm a dyed-in-the-wool Imperialist, and make no apologies for it.

Standard off-the-shelf metric fasteners just do not look right in most of the scale type models that many folk build.
When a lot of models seem to use socket head cap screws as fasteners, it makes little difference what the thread is, but for a scale appearance, then Imperial screw heads and nuts are far more in keeping with the prototype.
Metric threaded screws with scale type heads are available as substitutes for Imperial and one source is:

Dave
The Emerald Isle
 

Steamchick

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As many engines from the early 20th. century were Metric Bore and stroke - just converted to the nearest Imperial dimensions (64ths of an inch), is is something I grew-up with is the workshop in the 1960s, and converting the "Metric" by order of the government never really affected me. So I have "mongrel" engines, etc. with whatever suits the individual application within the project. Metric Ball-races, seals, O-rings and some materials, fixings where mostly hidden, or because "it makes sense". Imperial - Whit, BSF, NC, anywhere it fits with existing stock materials I have to hand, and BA - mostly for electrical (as it was originally intended?) - but also as small Whit etc. are not so practical in many applications. It helps differentiate getting the right fixing in the right place. Incidentally, the English Language is a mixed-cnstruction of Central European, French, Latin, Greek, Celtic, Gaelic, Norwegian, Danish, various Indian and African languages, even Mauri and Aborigani and other various tribal languages, Chinese, and Japanese, and other Asian languages, Eskimo (Inuit?), and many more I can't remember, so having threads (like this web-conversation) to join together all those language threads seems like a useful foundation for the diversity of (screw) threads....
Somebody switch me off....
 

bazmak

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I have quite few ba taps and dies and if ba hex hd screws are available then i use them
When i started 3 1/2g Heilan Lassie a lot of screws were ba but i found that m3 to m5
were very close and hx sock cap screw cheaply available.Grub,csk button and cap. A lot of
purists would frown on them but in certain situations they look great. Hex hds can be obtained with
smaller hds nearer scale. I did use ME threads for pipe fittings etc. Answer to your question is
use whatever suits you. Hex sock csk screws are a big improvement on slotted
 

goldstar31

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Somebody switch me off....
And Shakespeare actually invented words. Not quite inventing 'rude mechsnicals' in Midsummer Night's Dream but you get the idea. And wasn't a Geordie/Makkem responsible for the Lexicon???????. Alice's Dad!
I've a 1941 Machinery Handbook- which the intellectuals are supposed to browse- whilst bathing and perhaps the best 30 quids's worth in Thomas's Model Engineer's Workshop Manual. Of course there is a reference to the attributes of how waterproof a duck's anus is. Amongst certain model engineers who apparently have peculiarity giving embarrassments.

Thinking of the Inuit, I once put their dictionary( at the time) into a pair of Antarctic Auster 7's-- on their way to ------ QueenMaudland in Antarctica.

I have known the bowels of despair.
 
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tornitore45

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I see the Metric/Imperial standard dimension as a continuum on the size line. There is always a metric size between two contiguous standard Imperials and there is always an Imperial size between two contiguous Metric. I pick the one that fit best or the one I have on hand. Metric tend to have a finer pitch so are easier to tap on harder metal, that may determine the choice sometime.
 

comstock-friend

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While we are on the ME threads, are they 55 deg Whitworth or 60 deg??? I have pretty much a full set of taps and dies to 9/16. Mostly English but some US. Wondering if the English are 55 and the US 60 degrees. The US are not marked 'ME'.

My current Stuart beam engine has 10-32 for 2BA, 5-40 for 5BA and 3-48 for 7BA, although I have taps/dies for both the ANSI and the BA. I also changed from mostly bolts to mostly studs/nuts and washers, with smaller pattern hexes for the ANSI threads than hexes supplied by Stuart.

John
 

awake

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So this may be a chance to ask a question I've been pondering for some time.

Since England changed over to the metric system ... why is the currency still the pound? Surely, to be consistent, it ought to be the half-kilo??

:):):)
 

goldstar31

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It's because we buy gasoline and Diesel by the litre and calculate how many miles that we get to the gallon. We all understand feet and inches and have nuts and bolts- in metric sizes. My son yestrday blew up the tyres of my sit on lawn mower and disabled scooter- now he speaks French better than the average 'grenouille' and we were talking abouts pounds per square inch. Wh en we have been in the Dordogne, we talk kilos and drink the vin du pays but we drink whisky without the Irish and USA 'e' in in it. Vive la difference and stoned out of minds cut our 'sauscise' with an Opiel pruning knife when we know that in England, we'd be arrested for carrying it because here it is an offensive weapon.

He's making a new garden gate in 50 x 50 timber which is 2"x 2"- but less because it is PAR- or planed all round when it is square.

Our horse racing is measured in miles and furlongs and our race horses are measured in hands.
We produce statistics and the prss will quote 50% whereas we know that it is approximately half - give or take a gnat's cock.

Surprisingly, the Spanish loy- well mine are Catalan, work in both Imperial and Metric and the supermarket prices were quoted in pesetas as well as euros. I bought a house costed in pesetas per square metre for £7000 and 5 years ago after paying all fees, taxes and whatever, cme out with £168,000-

which is ----- a lot of Myfords:p

Clear as Merde?
 

Steamchick

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As a boy I was taught that one egg is Un oeuff (enough), but two eggs are more than one deux oeuffs (deserves).
Sur la pont d'Avignon... et vive la differences!
 

goldstar31

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Of course, I've 'done' the Rhone and also 'sous le Pont d'Avignon'. Actually it is only part of a bridge, the other section was washed away. As for dancing, no- too many gypsies, I'm afraid.
Of course, Avignon was the summer Palace of the Popes. Camped there, took my wife there later and down to the Pont du Garde and Les Bouches de Rhone. Cathar country. Crusaders left from there to fight in the Crusades. The White Horses of the Camargue. French is spoken with a cowboy drawl.
The. odds are very high that my son will sell up in the Dordogne and when I 'snuff it' their share of my house here and my investments etc will be sold up- and they will move somewhere to the West of the Rhone. Perhaps Aigues Mortes - or Dead water- now 7 miles inland of the delta.

Back to that rather bilious Myford.
 

BaronJ

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Hi Norman,

There is nothing wrong with green, even if it is a little bilious.

I bought a 2.5 Ltr tin of what was supposed to be "Myford Green", I now use it on everything that needs painting, even though its even more bilious ! But is does darken with age exept where the sun shines on it. Then it gets lighter.
 

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