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[Neil]

Here is that International boundary again.
What is a piercing saw, Tobyker?

Cheers.
Neil.

[kiwimodeller]

Hi Tobyker, would love to see a picture and some details of where to get the reversing valve block when you are allowed a break from chores. Cheers, Ian.

[tobyker]

One of these. Fit the blade so it cuts on the pull stroke. Very useful indeed for fine cuts in metal or wood.

[tobyker]

The reversing block, supplier as shown. (There are other suppliers of bits for Mamod and MSS locos.) I've already opened out the ports so I can solder in my 1/8" biro tube steam pipes., The outer threaded holes are for fixing the block between the frames of the loco - the ends of this block may well disappear as I probably shan't need mounting brackets - I think the pipes will hold the block in place. The steam inlet and exhaust pipes just push into the holes in the back of the block, and are held by the O rings and the 3-hole plate, pushed against them by the spring. I shall be ditching the O rings and plate, and soldering the pipes in. If you go to the Dream stream site there are so far as I remember expolded drgs of the loco so you can see how it all fits together. MSS do a vertical twin marine engine using this block and the loco cylinders, and if I feel like it I might even have a go at cobbling together a V twin from MSS parts. I forget what the other supplier is called but googling MSS or Mamod parts will find them.

[Neil]

Note to Tobyker,

I can't thank you enough for your help and guidance re the "V" twin. Very innovative of you indeed. Thanks for the link too.
We call that saw a fret saw. There were many sizes from memory. I have a couple here, one just like that, and another about half as big again. My memory is trying to find another name too, but it wasn't piercing saw. Fret Saw, and something else. (Isn't getting older wonderful?)
Neil.

[Bunkerbarge]

Are you thinking of Coping saw?

[Neil]

That's IT!!   

Da, da! Go to the top of the class,      (and thanks.) My memory is worse than I thought. (I just can't cope!) Sorry, I couldn't resist it.
Man, have I learned a lot in a week or two on this forum.
I'm wondering about adhesives though to go on the old boat's keel, made of ply, and is separating badly (I don't know why, it's only 60 years old).
Would Araldite do the job?
Is it waterproof? (I know 5 min Araldite is not.)
And, what about paint?
I suppose that's a bit different, as it will only be in the water for an hour tops, and a week to dry off.
I have been using paint from the motor trade on my boilers (if painted) and engines. The paint to which I refer, is what the go-boys use on their disc brake housings, and others on the engine block.
Any comments on that, for water resistance? (I suppose I ought contact the manufacturer.) But, I would value this forum's opinion over a salesman flogging something.
Cheers Neil.

[kiwimodeller]

Great, thanks for the pics of the valve. Exactly what I have been looking for. I have had one attempt at building one and the less said about that the better! Cheers, Ian.

[Circlip]

Coping and fretsaws usually have blades with cross pins in the ends like a "Phillips" junior hacksaw. Piercing saws are normally used in the watch/clockmaking trades for crossing out or piercing the train wheels and are straight bladed retained by finger clamps.

  Regards  Ian.

[tobyker]

The ST engine has it's inlet and exhaust ports at the sides of the standards. This is not very convenient when it is V-twinned, as you have to pair both LH ports and both RH ports. I had opened up the port drillings at the tops of the standards, but even using one top and one side port would still involve long convoluted pipes. It then occured to me that I could drill into the backs of the standards, and pick up one set of port drillings at the top, and the other at the bottom.  The first photo shows the openings I made in the backs of the standards - you can see right through some of them and the openings in the port face. I had considered drilling through the ports to break out of the back of the standards, but I reckoned that would carry too much risk of distorting the ports. The second  and third photos illustrate a further problem - because of the geometry of the holes in the standards and the borings in the block, they would not line up without the block touching the flywheel, and at least one of the pipes going through the cylinder springs. However the outer holes in the block for the mounting screws are not bored right through( as are the steam holes). So you can drill out the threaded hole to take a pipe, and drill into the block at right angles to the bores so that the screw hole connects with the steam hole. In the event I used one steam hole and one fixing hole each side of the block, leaving me with two 1/8 holes and two 2mm holes to fill with bits of brazing rod.

 I bent the thin walled brass tubing by using a suitable electrical wire from 3-core cable, smearing it with Vaseline and threading it through the annealed tube. I then made two bends in each 4" lenghth of tube, bending it round the top end of the steel shaft of a small hammer. The tube did go slightly oval, so I pinched it round again with a finely adjusted Mole grip. I then cut the tube in the centre between the two bends with a tube cutter, and pulled the two pieces apart. when one was free of the wire, the long end of the wire goes in the vice and the tube is pulled off the wire. Then anneal the four tubes again to give some flexibility for fitting. Then its just a matter of cutting the tubes to length and heaving things about so four ports are connected to four holes in the block, the block sits square-ish-ly to the engine and none of the pipes has to pass through anything solid between the two.

[tobyker]

The side ports which were now redundant were blocked with unions filled with a piece of brazing rod upset , whacked in from the inside and then soldered. I cut a screwdriver slot in them so I could screw them in. The holes in the top of the standards, the redundant steam holes in the block and the ends of my drillings in the block were filled by more bits of brazing rod, greased with flux paste, hammered in and soldered when the pipes were soldered in. The block was heated three times - once to solder the holes up, once to fix the distributor pipes, and a third time to fit the main steam and exhaust pipes. Pictures of the finished article belw. She seems to run quite well on air, though better in one direction than the other. Maybe she always did - I've not been able to switch rotation without disconnecting all the pipes before. I will investigate and see if I can find out why.

Finally, an apology to all those proper engineers on site who I have upset with this little saga - I think I am probably K N Harris' much despised "practical man"! Still, I have fun playing with little engines in my way and I hope everyone  else does in theirs. I'll have to build a boat for the engine now.

[Neil]

Again I thank you Tobyker.
Very inventive. I will "give it a go" over Easter.

Neil.

[kiwimodeller]

Received a steam control valve from Dream Steam today, very good service to have it too the other side of the world in less than a week. I too will be enlarging the ports and soldering in larger pipes. I am a little concerned that it may be too small for the engines I have coupled together which are 5/8" x 3/4" double acting oscillators but I will give it a go. I was interested to see in the early pictures that you used flexible tube on steam and exhaust pipes. Was this anything special? Did you use clips to hold it on? In the early stage of experimenting it would be much easier to use flexible pipe rather than bending up copper tube but I have not tried this previously so any advice is welcome. Thanks, Ian.

[Neil]

Good on You Kiwimodeller,

My valve, despite being paid for well over a week ago, has not reached OZ, and NZ is eve further away.
Maybe I have been "dudded"?
On the flexible pipe thing, Saito do it, (I'm not sure if they still do), but, mine, (a tripple plant), for the astonishing amount of money, by the time it reaches OZ, I think a bit more than hospital tubing should be in order.
Maybe they should get lessons from Nick, as to copper tube bending and soldering. (I'll be in the front row when lessons start.)

Neil.

[kiwimodeller]

Attached (I hope) some photos of my attempt to couple together two P & M Research single cylinder double acting oscillators to make a self starting reversable engine setup for a paddler on the cheap. At the moment they are mounted up on my "try anything" mount to put them in my Waimarie side wheel paddler which I use to try out every steam plant idea I dream up. It is easy because she has a huge amount of room inside and it is easy to couple the engine/s to the paddle shaft with a chain. Eventually I intend to build a sternwheeler for these engines and put the original Rayman back in Waimarie. I received the control valve from Dream Steam earlier this week and took Tobykers suggestion to solder all the pipes in place. Ran the engines on air today and although the valve worked as designed I found a couple of potential problems. At anything less than about 30psi the engines would not self start even though they are double acting and coupled at 90 degrees. This might improve as one engine is new and needs running in. The other potential problem is that at anything over 20psi the control valve leaks quite badly around the periphery of the valve. I guess this is probably because it is designed to run on a little pot boiler of not much pressure. I have played around with some small tube spacers behind the spring on the centre pivot of the valve to up the tension and it seems much improved. The engines are now in the boat and ready to test on steam tomorrow after work and hopefully to sail on Sunday. Will post the outcomes. Cheers, Ian V.

[tobyker]

The flexible pipe is just silicone tubing as used for w/c engines from the local (!) model shop. I did find the control valve leaked as well - I had tried lapping the faces on (Robert Graham's) emery paper but the lands on the movable part are quite narrow. More steam oil might help - I'm still trying to get my home made lubricator steam and oil tight. I'd suggest, if you can, mounting your reversing block higher so you could have less pipe length in the setup - I wonder if water condensing in the pipes is giving you the starting problem? Also to save weight, if you want to, you could use only one flywheel - my setup does that and runs quite well.

[kiwimodeller]

The valve is much better once I fitted a piece of brass tubing over the screw to put more pressure on the spring which is now almost coil bound. The valve still moves smoothly and I am sure it will work with the radio. I tried things today on steam (yesterdays tests were only on air) and the valve worked well and the engines will self start one way and almost the other. I am sure this will improve when the second engine is run in as it is still leaking steam at the oscillating surfaces at the moment. The piping is only temporary, when the engines go in to another hull I will mount them horizontal with the valve just above them. Thanks for your suggestions and the contact for the valve. Regrds, Ian V.

[tobyker]

Glad to hear of progress - I'll try packing my spring out a bit too! Look fwd to seeing pics of engines in boat and action photos.

[Martin (Admin)]

How large do oscillator engines go?
 Are oscillating engines just suitable for models?

Bet you didn't know this!

http://www.catskillarchive.com/rrextra/odcuri.Html

(near bottom of page)

[tobyker]

Well found, Martin! What a delight to read. I should imagine that perching a perfectly good locomotive design upon another set of wheels, as in some of the designs shown, must have made going round corners jolly exciting!

[tobyker]

This should be a link to a picture of some fairly hefty oscillators!
http://en.wikipedia.org/wiki/File:Oscillating_engine,_and_boilers,_of_Great_Eastern_-_gteast.gif224kB.png