Building Stuarts Compound Steam Engine

[saw]

 Building Stuarts Compound Steam Engine
Hello Gentlemen.
It was a while ago sense I have built something, in fact nothing sense I finish my D10. I have been full up with a lot of other activity..
For a while ago I manage to get my hands on a Stuarts Compound casting, it’s impossible to buy from Stuart Turner so I was very pleased to get my hands on this for a good price.

This casting is radar old I believe from 1980 but looks radar god, so now I am going to put up a building log here, I hope that you will like it   

[Rob.Wilson]

Evening Benni

I will be tuning in for this build  ,, the castings do look good quality 



Rob

[krv3000]

yep i will be tund in to this to

[Don1966]

I am in on this built. I want to build a compound engine so I am in till the end.

Don

[Dan Rowe]

Any marine engine will get my attention for sure, I have some old Stuart kits that will make it to the bench sometime so it will be fun to watch this build.

Dan

[Don1966]

There is a built on http://compound.modelengines.info/ on the compound launch you made be interested in. Still following with interest.

Don

[saw]

The Soleplate
Hello gentlemen.
Thanks for nice comments, I know that this project will take a long time for me to build, but who is in hurry?
Don1966: Yes I know this gentleman, in fact it’s thanks to Mr. John R. Bentley that I found this casting.The first picture shows the Soleplate from the top..

..and the next from the bottom.

The first thing was to use a flat file to smooth over the bottom. Then check out where all the holes, and fixes the midline. After that some work in the mill




I was using a center drill to mark out the midline, and then I have to drill for the columns.
..and threading for the columns


After that I have to drill the whole for the main bearings and smooth the surface.


And even some milling on the edges

 And the bottom.



 Then it’s was necessary to use a flat file emery cloth and a bit polish.

So far I am quite happy with the result  .  I have measured and measured again, but things seem to measure up. The soleplate is very important, everything here  must be correct otherwise I think I will have some problem.. 
I’ll be back.   

 
 

 

[doubleboost]

Hi Benni
You are off to a good start 
I do like marine engines
Looking forward to future installments 
John

[NickG]

Hi Benni, looking forward to this one too, bit different from the norm. Wish I could get my hands on some cheap castings as I am keen to have a go at some, however the price seems to have shot through the roof in recent years!

Nick

[Alan Haisley]

Benni,

This looks like you will have a lot of fun with the build. I'm tagging along to share in it. 

Alan

[saw]

Hello gentlemen.
Thanks for nice feedback, it always helps to make the project just a bit better when feedbacks are dropping in.
Columns.
Now it’s time for the columns, there are five and made of mild steel. According to Mr. John R. Bentley, it would be nice to make some small modifications comparing to Stuarts drawing.
They want to have 2BA on both ends, but I am threading 2BA on one end and the other with 4BA because the nuts will be too big with 2BA.


With some turns in the lathe will give me the dimensions for threading 4BA.


After all columns were finish I drill and thread the nuts.
 
 
The nuts fit radar good…
 
 
.. and it don’t looks so bad either.
 
 
This was just a small update but..
 
I’ll be back. 

[Stilldrillin]

I'm watching quietly, Benni. 

I have to say your machined surfaces are much brighter than Rob Wilson's...... Well done! 

Good luck with the build..... 

David D

[rudydubya]

A really nice finish on the soleplate Benni.  I'm looking forward to following along with your build.

Regards,
Rudy

[saw]

 Main Bearings
Hello Gentlemen
Thanks fore nice comments
Now it’s time for the main bearings, it’s a little tricky because it’s very impotent that the main bearings are in strait line to the soleplate for the crankshaft. Otherwise it will be a major problem.


The first is to milling the edges…

… and the bottoms.

Then mark out for the center line and the bolt holes.

Drilling the bolt holes…

…and checking that all fits good together.

Then marking up the centerline with a center dub.

Milling the top for the nuts to fits better.

Is it beginning to looks good?

Now with a ¼“ ball nose end mille mile the main bearings for the crankshaft…

…and also the soleplate.

The last is to drill and reaming for full size. I first drill 6.5 mm then 6.8 then reamed for 7.00 mm. Then drilling for 7.5 and 7.8 and finally reamed for 8.0 mm.

And here we go, it begins to looks radar good…
…and all dimensions are perfectly suited.
I feel radar happy so far, but it’s much work to be done before I can see the end…. 
I’ll be back.
 

[NickG]

Hi Benni, I would never have thought of that method for the bearings - unorthodox but looks to have been very effective! Well done

[mzt]

Hi Benni,

I have ideas that Your method of drilling the bearings worked because You went from 1/4" dia. to a round and straight (as much as reamers would do in those fields) 7 mm in light steps.

I had recently tried drilling a (large) split bearing I had bored undersize and then split using the remaing 'oval' as a guide for a larger drill.  --> Scrap
Next one, I tried milling a square groove on the bearing line, into the two halves. --> Scrap again.
What worked for me was milling an identical V groove on both halves of the third workpiece.
Not sure I will try Your method on next occasion. Neither sure I won't, though.

Nice work, btw.  I'll be following this thread.

Marcello

[Stilldrillin]

Those bearings were very nicely done Benni! 

David D

[sbwhart]

Looking good Benni I,ve bin following along quetly 

Stew

[saw]

 The Crankshaft 
ThanksNickG, mzt, Stilldrillin and sbwhart for nice feedback.
You are so right this is not the ordinary way for drilling the main bearings, I tried many different ways and a lot of coffee before I came up with this solution. However it works and that is all that matters, right?

Now to the crankshaft, I am sorry, I use to take a lot of picture, but I have forgot some in the beginning.
I cut off tree pieces of 8 mm silver steel, one 150 mm, and two 19.1 mm. On the small ones I turned down a 4.95 mm long edge to 7 mm at both ends.
Then I cut off four pieces of mild steel...

… and market out and drill two holes, one 8 mm and one 7 mm. I drilled undersize and reamed to correct size.

Then some turns in the lathe so I could get a smooth radio…

… and back to the mil for drilling holes for the pins.

After that I assembled all the pieces...

… and drilled the holes for the pins, mount the pins and soldered the pieces together.


And here we go, we have a crankshaft. I know that many people preform to turn the crankshaft in the lathe, I have tried that a couple of times so I took it safe rather than sorry.

So far so god but… 

I’ll be back

[NickG]

I like that method, same as I used for the 'poppin' flame lickers although I didn't pin as the power of them is so low. Didn't you fancy trying the cast crank then?

Nick

[saw]

The Flywheel.
Hello Gentlemen
Thanks for nice feedback.
 Well, now it’s time for the flywheel. It’s not a tricky part, just a few turns on the lathe.
 First in the lathe, I fix the surface and drilled and reamed the hole for the crankshaft..



…then then half of the outside…



…after I did the same with the other side.
Then drilled and threaded for the stop screw.



After some polish…



Not too bad. This was just a miner update but…   

I’ll be back.

[saw]

Crosshead Guides.
Hello Gentlemen
The update continues, this time it’s the crosshead guide that need to bee done.
It is therefore critical that all dimensions must be exact.



I first begun with the fly cutter for a smooth surface…



… then some milling and …



…drilling and reaming the holes for the columns.




Then milling the radios…



…then drilling…



…and threading for the stop screw.



And now checking…



… and it looks like everything is ok.


Even this was just a miner update, but those things are necessary for the complete engine.
I’ll be back.

[Ray]

That is really looking great.

Ray

[Stilldrillin]

… and it looks like everything is ok.

And.... Everything looks ok from here too, Benni! 

David D

[saw]

Hello Gentlemen.
Thanks Ray Stilldrillin for nice komments.
Oil Cups

You must be wandering what I am up to, but I feel to play around a bit with the oil cups.
Ones again I follow a suggestion from Mr. John R. Bentley  and I am not going to use brass, instead I am using hexagon steel bar.

 
As you can see on my skis, it’s a very simple oil cup, but it will stand out.
So, first in the lathe where I marked out the length and prepare for the threading.

 
Then I threaded the oil cup…

 
… and some deep turns so the threading can go to the bottoms.

 
Then some more turns on the lathe …

 
… so that I can shape the cups.

 
Then drilling a 1 mm hole from the bottom.

 
After cut off I turn the cup around and drilled 4.5 mm hole.

 
And after some clean up I feel radar pleased.

 
And they fit well with the rest of the engine.

 
Again no big update, but now it will take a while before I post something new, I will begin whith the cylinder block.
I’ll be back