Stuart Turner S50 , a Little Help required for Tap sizes !

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pirmin kogleck

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hy

i want to build a stuart turner s50 steam engine , and therefor i need to buy me a few Taps and Dies , and i noticed that there is quite a mix between BA and BSW or other type of threads on the buids from other people !

does someone maybe know the exact taps and Dies wich are required from the drawings ( i realy want to use the original tap sizes !

so a its of the taps ,
Dies
clearencedrills

would be highly apreciated !

pls if someone has the preices infos , i would be very very happy since i only find different info from different builders.
 
from stuarts
 

Attachments

  • Stuart T&D.pdf
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it is not available to open that ! can you make a picture with the phone and send it ? when i open it it say service temporarly unavailable
 
Try this
Stuart T&D.jpg
 
great it works , only one or two more questions , the TPI is this Model engineer threads or british standard withworth ?

aldo the steam union for the inlet and exhaust ( do you might know the sizes ) for the pipe and the unions ?
 
The40 and 32tpi are ME threads

Both engines 3/16" x 32 ME inlet thread and 1/4" x 32 ME exhaust thread

Both engines 5/32" inlet pipe size (OD) S50 suggested 3/16" exhaust pipe and 10V has 1/4" exhaust

Smallest oilcups threaded 1/8" x 40tpiME
 
My suggestion for buying these is to go on "Ebay.co.uk" and search for them. There are large numbers of individuals who are cleaning out estate shops, and have all kinds of taps, dies, and drills to sell.
I wasn't going to bother with BA taps and drills for my Stuart kit, thinking I would just covert everything to the closest U.S. dimension, but after finding out how much is available, and how reasonable it is in price, I have now got a full set of all BA taps and dies, in starting, plug, and bottoming, plus a lot of extras as spares. The shipping is kind of a pain in the butt, but this stuff doesn't weigh very much, so postage from Great Britain is not that bad.
The other important thing about BA fasteners, is the range is such that there is nearly always a perfect size for the correct nut and bolt, that both works perfectly, and also LOOKS RIGHT. I didn't realize this until I started getting into BA stuff. BA, from BA1 to BA10, moves in perfect progressive steps as far as sizes and realism go. Converting over to U.S. means there are some places that there is no U.S. fastener that looks good in a particular position. U.S. threads move in irregular steps, without a gently progressing size difference, so if you use U.S. threads, you find some fasteners look too small, and others look oversize (Which is WAY WORSE) Oversize fasteners just completely spoil the magical miniature effect on engineering models. You CAN go undersize, and have it look OK. but if you go OVERSIZE, it looks very clumsy and kind of ruins the look of the machine you are building.
With BA, you can take a photograph of a machine you are building, and you can't tell it is a model from the picture. It could be a picture of the real machine.
Just my opinion. Others may vary.
 
The other alternative being in Europe is to just go metric and buy in some new fasteners and even bar stock. The main fasteners on both engines are 7BA and M2.5 makes a good replacement if you use the small hex fasteners available from several German suppliers such as GHW. 5BA becomes M3

Also if you are intending to buy pipe fittings etc in Europe then don't thread the steam inlet and outlet with ME threads as all the fittings sold on mainland Europe use metric fine threads so inlet would be M5 x 0.5 and Exhaust M6 x 0.75. You can also use these for the rod glands.

Here is a Victoria that I made with all metric fasteners (small hex) which look fine but standard size hex would be too large.

 
Just decide what you are doing, then order from these guys...
TAPS & DIES (INC L/H THREAD) (All Taps & Dies sold separately) (tracytools.com)
Always give me good service at a pretty fair price. I met a guy from Sweden, who was travelling across to the UK to buy a van load of stuff from Tracy - because of the quality and price - for his Swedish business! - He did over 15 trips a year (or so he said).
That was the best recommendation I had heard. But I have bought from them since the early 1990s. (Pre-computer purchasing! - "On-line" meant paper orders and cheques by post!).
K2
 
My self I use taps and dies that have on had and try keep to a few sizes.

The only time I do not this is in rebuilding/repair. I have taps for rebuild upto 1 3/8", British pipe dies and gun site taps.

I even try keep nuts and bolts to few sizes. This does not work most time.

Dave

hy

i want to build a stuart turner s50 steam engine , and therefor i need to buy me a few Taps and Dies , and i noticed that there is quite a mix between BA and BSW or other type of threads on the buids from other people !

does someone maybe know the exact taps and Dies wich are required from the drawings ( i realy want to use the original tap sizes !

so a its of the taps ,
Dies
clearencedrills

would be highly apreciated !

pls if someone has the preices infos , i would be very very happy since i only find different info from different builders.
 
I see you were asking about pipe unions and connections too, it's easier to reply here.

You can thread pipe and screw it straight into the threaded hole son the engine, if you do then it will need to a thick enough wall to take the 32tpi ME thread or change to 40tpi. I quite often do this as the nutted unions don't look right on scale models.

The alternative which can be more practical for an engine that is going to do some work rather than just tick over for display us to use threaded unions. These come in 3 parts - the union body, a union nut and a ferrule also known as a nipple or cone. For these two engine a union like this would suit where one end is threaded to screw into the 3/16 and 1/4 holes and the other threaded for a suitable nut. the nut end has a 60degree taper which the nipple seats into and seals the joint. These tend to be used rather than the "olive" ring found on domestic compression plumbing fittings.

The pipe is soldered into the nipple and can there for have a thinner wall thickness which means that a 5/32" OD pipe would be able to be used rather than a thicker walled 3/16" OD one if threade dpipe were being used.

So something like this. Well I was goning to link to Stuarts but they don't seem to be displaying the unions at the moment but this sort of thing, note most other makers use 40tpi ME but Stuarts use 32tpi so decide who you will get fittings from and thread to suit

Male union
http://www.steamfittings.co.uk/asp/d-no.asp?ProductID=261&Process=1
Ferrule or nipple these are included with the unions but just to show what they look like
http://www.steamfittings.co.uk/asp/d-no.asp?ProductID=101&Process=1
The nuts have a shoulder that fits on the larger dia of the nipple and pulls it into the taper
http://www.steamfittings.co.uk/asp/d-no.asp?ProductID=99&Process=1
For just running on air you can make your own adaptor to suit the air hose one end and the engines threaded hole the other, a simple way is to use a short length of 6mm dia rod, turn down and thread the end 3/16 x 32ME and then use the push fit PVC hose and fittings that are readily available, something like this setup of mine. $mm OD will be OK and you can also use 6mm but 8mm really only for bigger engines

 
Buy the whole set of BA taps and dies from the UK, {you will be glad you did} not only that you will need a good set of drills number size and fractional maybe letter size also.?
Do you have the tap handle and die holder taping center and a good drill press or milling machine..?? I got a set of BA taps and dies from a friend, he got them when he went to the UK one summer with his family, also he bright back some Stuart castings..
 
As for drills I'd suggest a metric set 1-6mm in 0,1mm increments. 35yrs of model engineering both imperial and metric models and I've never had cause to use a letter or number drill. fractional would be handy but a 1/32nd increment set should do 1/16th to 1/2"
 
As I remember the BA threads call for the number drill taping size, not that mm size would not be handy, at one time or other I have needed mm drills. McMaster-Carr {in the USA} sells mm drills and mm drill rod if you are looking {not easy to find sometimes}.
 
As he is in mainland Europe the metric drills will be easier to come by, also BA is a metric based system and tapping drill size tends to depend on the publication you look it up in.

Don't think either engine needs 115Cr-V3 either but can be found easy enough in Europe if you look for that designation. Or just "silberstahl"
 
For more years than I care to remember I have used 14 different thread types for various roles. Today I use the metric series and use the others for legacy projects/repairs. The exception is BA and ME which I use for all models due to scale and the extensive dimensional data. My recent Wyvern was BA with heads usually reduced for scale. I have number, letter, fractional and metric drill sets but only use metric. I use cheap drills for everyday operations where the hole size is not critical. For any accurate work and tapping I keep a set of Dormer drills which cut accurately. If I damage a Dormer drill I buy a replacement. The cheap drills I sharpen. Usually you have one shot at tapping a hole so certainty in it's size is critical. I occasionally use fractional drills, usually in conjunction with imperial reamers - I have a good set from way back!
Mike
 
As I remember the BA threads call for the number drill taping size, not that mm size would not be handy, at one time or other I have needed mm drills. McMaster-Carr {in the USA} sells mm drills and mm drill rod if you are looking {not easy to find sometimes}.

A 0.1 mm increment in size is 0.004". That is a small enough difference to allow a selection close enough to cover every requirement, including tapping BA. threads.

For tiny stuff like carb jets, tiny boiler feed injectors, or threads smaller than 12 BA (1 mm), a number set from 60 to 80 is a good idea.
 

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