Transitional Engine

[glue-itcom]

I've been making this engine for a long time, mostly down to the fact that the design is in my head and not on paper.

20190310_163040

• glue-itcom
• Apr 7, 2019

The basic idea is that it is a steam engine converted to run on gas and so something from around the late 1800's in basic principle - an agricultural engine.

The conrod is a slider and so in 2 parts:

20190310_163051

• glue-itcom
• Apr 7, 2019

The exhaust valve is operated by an eccentric that has a pushrod in two parts and this works via a bellcrank that sits off the side of the crankcase:

20190310_163104

• glue-itcom
• Apr 7, 2019

The inlet will just be a poppet valve on a spring - I need to find a good source of springs at different rates.

A lot more images and details on my pages: http://www.glue-it.com/wp/gallery/engines/transitional-engine/​

 

[Rudy from Norway]

I like this idea a lot. Hope to see more of this build. I also like your posts on that "glue it" place.
Thanks for sharing.
Rudy

 

[glue-itcom]

Thought I would post some more images showing the design and some of the machining steps

The crankcase, ok not much of it, was machined from a solid piece of mild steel.

A lot of machining steps to get to this point and quite a few hours in the workshop:
http://www.glue-it.com/wp/gallery/engines/transitional-engine-crankcase/

The crankcase bolted down to the I-beams.

 

[glue-itcom]

The crankshaft was machined from a quite substantial piece of mild steel:

 

[glue-itcom]

Lined up in the lathe for the first stage of machining

I used 2 nuts and a short piece of studded bar to support the crank for some of the next stages

The cable tie is there to keep the nuts in place when this is spinning, I didn't want this flipping out and hitting me.

just setting it up to ensure the final surfaces were all parallel

And it's all laid out in detail here:
http://www.glue-it.com/wp/knowledge/crankshaft/

 

[glue-itcom]

The frame of the engine was made from 1/2″ wide and 3/4″ deep mild steel

and then bolted together

I've been wondering whether to solder or TIG the joints, maybe
http://www.glue-it.com/wp/gallery/engines/i-beams/

 

[n1326e]

Soldering doesn't have the strength for this application. I'd suggest TIG as opposed to other kinds of welding, since it has more concentrated heat (less warpage). Tom

 

[a41capt]

Plus one on the TIG operation. More easily controlled heat application and a finer bead and fillet for scale. Brazing would be another possibility in this application as the joint is stronger than soldering, but it still involves more diffuse heat and the opportunity for warpage.

Neat project, I can’t wait to see the final results!

John W
Camp Verde, AZ

 

[Sprocket]

Since I don’t TIG, I would silver braze it. I made a bike frame that way once and built up fillets on al the joints. Silver really flows so fillets were not easy, but it’s do-able.

 

[Jasonb]

Silver soldering (silver brazing) would be my choice on a part like that, even with neat TIG you will get a fillet where you don't want it.

Having said that back in the day an engine bead made out of structural sections would more than likely have been bolted or rivited together. Pitty you put such a big fixing in already as a few small ones in each would have looked more scale.

 

[glue-itcom]

I'm not really after scale, more just a look. The cooling fins on the cylinder are not very scale and the head is definitely wrong, just somehow it has a nice look to it with regards to proportions.

 

[glue-itcom]

The conrod is a bit of a monster as I machined it from mild steel

Several stages of machining, silver soldering

more machining

and a lot more machining to get to here

and on the engine as a two piece conrod with a slider it does look rather good

there is a lot more to do on this engine and some parts need modification, some parts need to be thrown and to start again

 

[glue-itcom]

I changed all of the design for the cam operation and decided on an eccentric. This then took me to the idea of using a bellcrank to align the pushrod.

The bracket itself took me some time to machine

I still have a lot to do and this engine is a labour of love that I work on when I get inspiration. Best regards, Nigel
More details of the build are here: Transitional Engine

 

[Charles foster]

I just rejoined this group and one of the first posts i read is about this model. My dad is busy restoring a full size engine that with the flip of a lever you could run it on steam or gas. The picture that i attached is not the one my dad is working on but it is the exact same.
The engine weighs aprox. 2800 pounds.

chuck

 

[glue-itcom]

Hi, that's interesting, if you get a chance for more images of the restoration then they would make a great post. Thanks, Nigel