Stuart Beam Engine

[MalcBParticipant @malcb52554]

Had promised myself for a long time to make a beam engine.

I managed earlier this year to get my hands on an unstarted complete castings/raw materials/fasteners kit for the Stuart Beam Engine. One or two extras such as extra valves and lubricators were also included. Luckily at a decent price away from the Bay.

The negative being that this package had been originally purchased in 1975 and consequently stored since. With this was the original drawing package. I then bought a new copy of Andrew Smith's Stuart build guide.

As his build is lathe based for both turning and milling. My methodology adopted, has differed slightly being able to carry out milling on my 626 with 3 axis readout. I started in October on an " on and off basis " twixt doing other things. I think I am about half way through at a guess.

Having done a search I found 4 posts only on the Beam, one of which being on the eccentric raised an important issue.

Distance on my drawing for the eccentric centres is 11/64".

Andrew Smiths description shows 11/64".

The drawing in Andrew Smiths book shows 9/64".

One of the posts makes reference to a later ( 1993 ) Stuart drawing showing it to be 9/64".

I know it's a bit late in the day but I have been following the dimensions in his book rather than my drawing and now having 2nd thoughts about this, so a couple of questions please if anybody is able to answer:

1) If the build of the Stuart Beam has been covered in Model Engineer, how would I find out which editions if at all possible?

2) Do I need to go to Stuart and buy the latest set of drawings or can I continue to use the drawings in Andrew Smiths copy like I have been doing?

P.S. I hope the grammar police don't read this.

[MalcBParticipant @malcb52554]

W.I.Progress

[Jens Eirik Skogstad 1Participant @jenseirikskogstad1]

Write a e-mail to Stuart: sales@stuartmodels.com. Tell more precise which beam steam engine you have in your hand and write which problem you have with this construction and measure etc.. , then the staff in Stuart Models will give a answer to you.

Happy new year.

[JasonBModerator @jasonb]

1. Go to one of the online index sites for ME and put Stuart Beam into it, I use this one but don't think it wa sfeatured.

2. I'll have a measure of mine later and see what size I used, built in the late 80s

[JasonBModerator @jasonb]

Just put a DTI onto my eccentric and get 0.284" movement which is not bad considering at the time I would have marked oyt with a ruler.

So looks like 9/64th (0.141" ) is the right dimention.

J

PS now need to work out why the piston is siezed solid

[MalcBParticipant @malcb52554]

Posted by JasonB on 01/01/2016 08:22:39:

Just put a DTI onto my eccentric and get 0.284" movement which is not bad considering at the time I would have marked oyt with a ruler.

So looks like 9/64th (0.141" ) is the right dimention.

J

PS now need to work out why the piston is siezed solid

Thanks, happy to use the 9/64" when I start the eccentric. Your marking outs practically as good as jig boring

. I have concerns about if there are any more differences, so as advised earlier I will contact Stuart to see if they are willing to advise/assist.

[Ian S CParticipant @iansc]

Jason, did you put WD 40, or the like in it to keep out the rust? Or is it gummed up with steam oil?

Ian S C

[JasonBModerator @jasonb]

Don't like putting WD40 in as it tends to dry out and make things stick.

Think it was just dried up oil (not steam oil) as I was last run on air and maybe a bit of rust from moisture in the airline. Luckily it had stuck at BDC so a good shove downwards on the other end of the beam has it moving again, will hopefully have the compressor out later to run up another engine so may give the beam a go as well to loosen it back up.

[BC ProfParticipant @bcprof]

I gave up using the very badly printed copy of the book ( what a waste of money !) and made mine up as I went along . ( a good friend calls our engineering drawings engineering 'file to fit ' instructions ) I used 3.5mm for the eccentric . Engine works OK with the standard length of operating lever .

Brian

[MalcBParticipant @malcb52554]

If you want to protect your cylinders from corrosion/seizure during storage periods, use a good quality marine fogging oil in them.

[John PurdyParticipant @johnpurdy78347]

I'm in the process of trying to complete a Stuart beam that I bought as a part complete unit in 1996. All the parts, plans and materials were there but no fasteners. I bought Andrew Smiths book and started on it about 2-3 years ago. My plans are dated 1972 and show the eccentric offset as 11/64. The book (1987 printing) is as you say 11/64 in the text and 9/64 on the drawing. After doing a little math to see what was the appropriate dimension to give the correct valve movement I decided that 9/64 was correct and that is what I made mine. Total valve movement required is .21825 to fully open the ports at each end, thus an eccentric offset of 9/64 will give this movement to the end of the eccentric rod and hence to the valve rods (#32 on the drawing).

If you do contact Stuart Turner let us know what their reply is please.

John Purdy

[MalcBParticipant @malcb52554]

Thanks John.

Sounds as though your plans are around same time issue status as mine. As confirmed 9/64" is what I will go for from other helpful feedback.

I did send Stuart an email this afternnoon for when they return after their holiday break. Expressed some concern about if there are any other changes I need to take into account from my old drawings.

Don't know if they will reply but will let you know the outcome if or when they do.

[JasonBModerator @jasonb]

The other one that springs to mind is that the position of the governor if you are going to fit one is not right so test fit before you drill the base or cut the actuating rod to length.

J

[MalcBParticipant @malcb52554]

Thanks Jason, it's in my thoughts to maybe do the governor. Probably buy the drawing set some time shortly.

[BC ProfParticipant @bcprof]

I think ( sometimes!!) that I should make it clear that my "waste of money " comment concerning Andrew Smiths book in my earlier post was not on account of the text , that was just legible, but the drawings some of which were so badly printed that it was impossible to read the dimentions . Is that fraction a 3 or a 5 etrc.

I blame the need for the book on the activities of the workshop mice who had taken time off from hiding everything from 10BA nuts to a lump hammer to using the crucial areas of drawings as nest making material.

Brian

[John PurdyParticipant @johnpurdy78347]

Reference to my earlier post (01 Jan) the total valve travel should have been .28125 (9/32), not .21825 as stated (a little dyslexia?).

John Purdy

[MalcBParticipant @malcb52554]

Thanks Brian and John.

[MalcBParticipant @malcb52554]

As requested.

Just to confirm kind response from Stuart Models in that on the eccentric should actually show 9/64" not the 11/64" shown on my older drawing.

They confirmed latest drawing set as being 1993, offering to sell me a set, if I have any further doubts.

Think I will carry on using book and drawings as book seemed fine as the drawings in there were from a later date than mine.

I will however buy the governor drawing set shortly.

Big thanks though on their customer service, appreciated.

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