A portable steam engine

[Firebird]

Hi

Not much machining done lately, I have been working out where things go. To help me visualise things better I made another jig from MDF to hold a piece of plastic pipe similar in size to the copper boiler tube. Its slightly larger but thats of no matter I just want something I can use to mount the cylinder on and take measurements from so that I can start to fabricate the crosshead and crankshaft etc.







I have made a temporary piston on a bit of 5/32 rod.

[Firebird]

Hi

As you can see I have started to mock up the engine and try to work out where things are going. At a steam fair this year I came across this beautiful little centre engine that had been saved and mounted on wheels.



I particularly like the type of crosshead. I like the openness of it compared to the usual tube type. I am going to use this type of crosshead on my model.



I decided to knock one up using aluminium to see how it looks. I have a bit of brass that I will use but i don't have a lot and can't afford to make a cock up.

I haven't bothered with all the detail just the main dimensions. I started by facing off then turning a boss which will have the piston rod gland in it similar to the one I made on the valve chest. I drilled 6 stud holes. A 1/4" slot was milled across and a piece of 1/4" square super glued in. The plan is to make it from brass so I will silver solder that one in.



Back in the lathe for a trim up and drill a 5/32 hole for the piston rod.



A 3/32" hole is drilled each side and 4 pieces of 1/4" x 1/8" flat bar has a 3/32" hole drilled in each end. A 1/4" square spacer with matching holes for the other end of the bars is drilled.







It doesn't look too bad. I can see one mod that is required. The bars need to be further away from the head as there is not enough room to get a nut on the studs. Thats easy enough to rectify. I might get time to play around with it some more tomorrow. When I'm happy that it all works I'll make the brass one.

Cheers

Rich

[Jasonb]

Rich this layout is quite like the one on the portable that was in ME earlier this year, drawings were well off but I did draw it out again, thi smay be of use.



J

[Firebird]

Hi

Thanks for that Jason. The slide bars are T section, I assume fabricated??

I played around with it some more this morning. Starting with some aluminium in the lathe its faced then a boss is turned.



Then over to the rotary table in the mill to have the 6 stud holes drilled 3/32" then machine the sides off the boss.



Followed by a slot to accept a bit of 1/4" square.





Thats better, I can now get at all six studs with enough room for the nuts. Also the more room for the gland which will fit vertically on 2 studs as in the photo of the portable above.

Just noticed that I have the 6 stud holes in the wrong place. I have to have them spaced so that a stud is at the 12 o/c and 6 o/c positions with a space between 2 studs at the 3 o/c and 9 o/c positions as in the first attempt otherwise a stud will be right on the steam inlet port of the cylinder. It just needs a bit more refinement before I attack the brass.

Cheers

Rich

[Jasonb]

Tees can be fabricated or cut from solid, you could also use angle like my Fowler
 

[arnoldb]

Looking good Rich 

With the hole positions needing shifting by 30^o relative to the bar in the head, the bolt clearance issue might go away as well, but it will still leave room to work with a small spanner (wrench) to tighten nuts 

Kind regards, Arnold 

[steamer]

That is really coming along beautifully!   I love the details you added to that crosshead!

Dave

[Firebird]

Hi

Thanks Jason Arnold & Dave.

Progress is pretty slow at the moment, I just don't seem to be getting any shop time. I have to work on Saturday this weekend but Sunday is a day out at the model engineering exhibition at Warwick exhibition centre  lots of boys toys and gadgets and things that will come in handy one day, cant wait.

Cheers

Rich

[Firebird]

Hi

Very little progress on the portable of late, I seem to be spending too much time on tooling projects so today I had a couple of hours on it.

I'm not happy with the mock up of the cylinder cover so today I decided to have another go at it but this time make it in one piece. Again I have used some ally as a practice piece.

First of all the blank was turned to size then had a groove machined with the parting tool.



Faced and a small boss turned.



Then part off.



A good opportunity to try out my rotary table with a 4 jaw chuck. After centreing the table under the quill its a fairly easy job to centre the part using a DTI.



I use DRO's so zero those. I have also got into the habit of zeroing the dials as well, if the battery fails at least I can get back to zero.





Machining away some of the waste.







Drill 6 stud holes



Drill and tap 2 holes for the piston rod gland.





Cross drill for the slide bars



This is how the gland will look. This is actually the gland from the slide valve rod which is a smaller size hole but gives an idea .



The slide bars assembled and tried on the cylinder.





Overall much better than previous attempts. It looks better and I now know I can machine it from the solid.

Cheers

Rich

[steamer]

Thats looking the part Rich!   Well done!

Dave

[Bearcar1]

That's pretty sweet, Rich. That piece looks like it "belongs" there and does seem to mimic the full scale version quite nicely.


BC1
Jim

[gbritnell]

Gee, 4 pages long and it took me this long to find it. I went back to the beginning and followed along. Nice project and great build so far. Your documentation is first rate. I know how much extra time it takes to shoot pics, edit and post so I can certainly appreciate your efforts.
It ought to be a unique stationary power plant when finished.
gbritnell

[Firebird]

Thanks gentlemen

May I wish all a very happy new year

Rich

[Firebird]

Hi

I have decided to get on and make the cylinder cover in brass now that I know the trial version will work. I need to get this part finished and fitted so I can move onto the next bit. Progress is really slow at the moment I just don't seem to be able to find any shop time

Anyway the following pics show yesterdays work.













There is quite a bit of cleaning up work to do yet but if I get the cylinder drilled and tapped for the 6 studs I can fit it and then start taking measurements for the next bit.

Cheers

Rich

[Firebird]

Hi

I spent a couple of hours trying to clean up the brass cylinder cover and didn't get on very well, it looks a bit of a mess. I'm not happy with it 

So back to the drawing board, well lathe and start again. This time I am fabricating it from 2 parts.

Start by turning, facing and drilling and reaming.



Then using an end mill to bore for the gland. I needn't have bothered doing this op right now as I will be machining it away.



Part off



Set up and centred in the rotary table on the mill. Machine a 1/4" slot.



Followed by a little shaping.



Drill 6 stud holes.



Drill and tap 2 holes for the gland studs.





Cut a piece of 1/4" brass bar.





set up in the brazing hearth, flux and add a couple of pieces of silver solder.



After siver soldering.



Its in the pickle now for a clean up. It looks a lot better than the previous version. Next job, when time permits is to put it back in the lathe and machine the face flush again and drill and reamer.

Cheers

Rich