Hemingway 1/12 Ransomes and May horizontal engine

Short vid showing a pumping pump! Pretty pleased it works

https://youtu.be/gcR3T1o1mfM?si=CO5cRB6f32kr6ZCA

Wonderful!  That's always encouraging when things work like they're supposed to! 

Kim

Looks like a very efficient pump for its size 

Per                 

Started on the cylinder of the ransomes engine. Machined some flats on to the cylinder radii to allow it to sit flat in the vice to skim the other faces (these need filing anyway later on so the flat won't be seen). The port face and the base were then skimmed flat and square to each other, the port face was fine but the base didn't clean up all the way which is no big issue. The ends were then skimmed as well to give me a flat surface to help with marking out.

This was then put in the 4 jaw in the lathe and centred before skimming the end to length (nearly, still got 5 thou to come off after I finish the bore) and then I started on the bore, hopefully will get it done tomorrow

Lathework for the cylinder is now finished, bore was opened up to 3/4" and was checked with a plug gauge to make sure it was parallel all the way, the counterbore was then done for the cylinder heads before flipping it in the chuck and machining it to final length and doing the other counterbore. Back in the mill now to do some small holes and slots

Drilled the 4 holes in the base and then marked not the port face for the holes for the steam chest studs and the mounting holes for the port face plate. These were drilled 1.4mm and then tapped 10BA. On this side I just have to mill out the 2 pockets which are used to access the mounting nuts and then mill the 3 steam ports

Bit of steam cylinder work tonight on the ransome and May engine. Recesses were milled out with a 3/32 slot drill before machining the 3 steam port slots. The outer ones are 1/8" wide and the exhaust port is 3/16". I drilled the hole for the exhaust and its all worked out nicely with it  being in the right place. Given it a quick flatting off on the surface plate on a bit of wet and dry, when it comes to the final tidying up of the casting I'll lap it to a finer finish. Very pleased with how it's shaping up, the casting has been really pleasant to machine so far

I'm  confused by the ports, with the exhaust port wider than the steam chest. If it will have a d valve, the steam in the chest will go around the side of the valve and straight out the exhaust. Or will there be another plate there??

Quote from: cruebyI'm  confused by the ports, with the exhaust port wider than the steam chest. If it will have a d valve, the steam in the chest will go around the side of the valve and straight out the exhaust. Or will there be another plate there??

There is another plate which goes between the cylinder and steam chest which has all of the slots the same length, the build article calls it a false port face

Quote from: samc88

Quote from: cruebyI'm  confused by the ports, with the exhaust port wider than the steam chest. If it will have a d valve, the steam in the chest will go around the side of the valve and straight out the exhaust. Or will there be another plate there??

There is another plate which goes between the cylinder and steam chest which has all of the slots the same length, the build article calls it a false port face

Got it! Thanks!

Bit more progress! The cylinder was set to 5⁰ using the angled parallel I have and then the recesses for the steam passages were milled 5/32". The passageways were then centre drilled and drilled 3/32". The cylinder was then flipped over and the same done on the other side. With that done I then used the Coax indicator to set the bore up and drilled and tapped the first set of cylinder head fixing holes 10BA, I'll do the other side tomorrow hopefully

Cylinder head fixing holes are finished, there are a couple of jobs left on the cylinder which I will get back to later (the position of the holes for the throttle spindle bracket aren't drawn so will do those when I've made up all of the rest of the throttle assembly down the line. Also another one to do later on is the drain cocks once I've decided which to use. It's a nice tight fit on the studs, looks like it will be a bit awkward to tighten the nuts up though later on

I think I'm at a point with the cylinder now to move on to the next part (probably the false port plate)

Started on the false port face tonight. This has got material to spare but the raised section the slide valve works against was only slightly oversized so I took the centre of this as a datum and double checked all the measurements will work out which they do. I then started taking the part to size in the mill, I just have the lower edges of the T to do now and then I will machine the faces flat and drill the holes. I have also put up a picture of how it sits on the cylinder, the raised section fits inside the steam chest cavity

Finished machining to size and slots marked out for the ports. Hopefully will machine them out tomorrow night if I have time. I want to lap the faces in which is why I didn't use a fly cutter

You are in a rather productive period right now and the results look good 

Per