C-612 Horizontal Steam Engine

[Jo]

One of the models that Coles Power Models used to sell was a C-612 Horozontal Side Crank Steam Engine. It is a rather large sized horizontal engine with a finished size of 300mm long and 230mm tall and 230mm high. With a relatively small bore of 32mm and a much longer stroke of 54mm meaning that it is an engine designed to run slowly and the 170mm diameter 25mm wide flywheel is going to provide a fair bit of momentum once it gets going. As with so many of the offerings from Coles this engine and the castings date from Lancer Engineering.

While many of you may know of Coles Power Models, you many not know so much about Lancer Engineering: Lancer Engineering was started by Emile "skip" Damottee as a result of him purchasing the rights to the V8 Challenger model engine in 1969, this model reused a number of the castings from Elmer Wall's 50cc four cylinder engine so he then purchased the rights to all of the Wall Engine designs from Elmer Wall's son Robert. To extend the range of models offered they also offered a couple of steam engines and this is one of them. The design was published in Miniature Mechanics in 1945.



Being an engine from "over the pond" I had never come across this model before and having investigated I cannot track down any that have been made, so I assume it was not a popular engine. I have only one picture of a finished engine and that is the rather grainy image from the Coles Catalogue. (I have a suspect picture that claims to be a C612 but the base casting is wrong    so I will not post that to avoid confusion. )

Somehow or other this set of castings turned up in the UK at Station Road steam which is where we purchased them from for my "not another 21st birthday  " present. As you may have noticed the set is not complete as it is missing the piston casting, cross head and the main bearing castings and of course there are no drawings. But an evening of fondling with nothing but a GA resulted in a set of dimensioned hand sketches which I will be using to make this engine but they will be updated as we go along 

Jo

[Jo]

The first place to start must be the base. It is too large to clamp in a vice to flatten the bottom and you would not be able to clamp it down to mill the bottom flat so this must be done by hand using a surface plate.

The technique is simple: cover the surface you want to flatten with permanent marker, rub it on some flat emery on a plate and the high points will show up as they are the bits without the ink on them    Give those a rub with a file, repeat until you are happy the casting is lying flat. It has got to be good as we will be clamping it down on its bottom shortly 

Now that it is flat it can be mounted on the surface plate and the distance to the tops of the bearings and the guide bar pillars can be measured and the amount of casting to be removed can be calculated. How much is to come off is a balance between where I think they intended the top of the crank to be and how much spare material there is on the bearing caps once they are milled down a bit  I will think about it over night....

Jo

[Jasonb]

Must try harder

<a href="https://www.youtube.com/watch?v=TyFJuojtMhk" target="_blank">http://www.youtube.com/watch?v=TyFJuojtMhk</a>

I think I would base the engines ctr height on the flange that the cylinder mounts to so they are as concentric as possible. I would have thought you could have got it upside down on the Theil, my RMC casting was a similar shape 250mm x 170 and that fitted the X3 with room to spare.

[Jo]

Yes that is the one that claims to be a C-612 but it has a number of "differences" between it and the actual castings/GA 

Jo

[Jasonb]

Yes, valve chest is not as shapely but he does say it was a restoration project so hard to tell how much of an engine he had to start with. Also much like Stuart's the engines may have altered over the years  as they changed hands and patterns became worn, damaged or just went missing.

[Jo]

I agree that the base plate and the connecting rod are original the video is not of sufficient clarity to say beyond that

Edit: I should mention at this point my set of castings came with 4 piston rings that are also wrong. I think they are supposed to be for a model locomotive 

Jo

[Jasonb]

Jo, found a decent B&W image, you can only click on the URL if you promise not to let big ears look at the other casting sets they had to offer

https://web.archive.org/web/20120114132110/http://www.colespowermodels.com/engines.htm

[Jo]

Thanks JB,

I think what we have proven is that there are not many of these models around and for that reason it is best I do not look to embellish this engine with a water pump or governor 

Jo

[Jasonb]

............................ it is best I do not look to embellish this engine with a water pump or governor 

Jo

Depends on how long you are going to have to wait for the next set of castings to be released from lock down

[scc]

I'm settled in for this one.    looks a similar layout to my Charlesworth engine.           Terry

[TerryWerm]

I will be watching this one as well, as horizontal engines are my favorites.

I often lament the loss of Cole's as they had such a wonderful variety of castings available.

 

[Jo]

You are welcome to join in with the fun Terrys 


I started by milling the bearing caps. While I suspect they should drop in 12.7mm and be 25.4mm wide I chose to make them 27mm wide as the gap in the base casting was not central and the extra would give me a bit of gap offsetting space in the base casting.

The machining of the top of the base casting was done on Tgs. I first put a piece of paper under the casting before clamping it down square. I had already measured the top of the base and the two surfaces I needed to machine the tops of and decided that the top of the main bearings and the centre line of the engine would have to be 90.5mm up from the bottom of the casting so that the top of the cylinder was just below the top curve of the casting. I should mention that the castings are rather tight  and by taking height off the crank centre line it effects the maximum diameter of the flywheel but we will get there 

Machine and fit the caps before drilling (yes I needed that extra 2mm to line it up ) and tapping for their bolts.  (I know the Coles original engine shows bolts in here not studs )

Once secure the sides of the bearing caps/base casting need to be made narrower to give sufficient space for the crank web, half the piston rod plus the edge of the main bearing. I decided to use a piece of square clamped to the side of the bearing cap to find where the centre would line up and work out how much had to come off each side of the bearing caps. The side nearest the crank web had to go down a long way to make sure it cleared the web There was a lot of measuring, calculating, measuring again before this was done.

While set up I also took the opportunity to mill the tops of the mounts for the slide bars and tap for their Dome headed bolts 

Having taken it off of Tgs bed I could now start looking at the challenge of the flywheel... it is a bigger diameter than the base casting has space for... but it will need to be about 168mm rather than the 175mm it currently is 

Jo

[Roger B]

That looks quite a beast, way beyond my machines  I hope it does run as slowly as the design suggests 

[Jasonb]

That's an odd shape of bearing cap, comes down very low but ends up with quite a thing cap over the top of the bearing, interested to see what you have planned for the actual bearings.

EDIT, looked at a blown up drawing and they are more "bearing housings" than bearing caps with a single flanged bearing and "washer" to go on the other side 

They do say 6 3/4" so will be a bit less than the 175 as cast.

[Jo]

EDIT, looked at a blown up drawing and they are more "bearing housings" than bearing caps with a single flanged bearing and "washer" to go on the other side 

It is a bit of an agriculturally designed engine without any refinements. I am finding it difficult not to reshape various bits and pieces to make it look better 

The castings are very tight on what I suspect were their original dimensions, not a problem for me as I am making it up as I go along 

Jo