Garden Railway Forum

Brilliant.....

I have been reducing the head height of roundhead screws to fill all the holes that I overeagerly drilled for the cylinder port blocks. Standard height is too close to the face of the port block. The frames are going to be black so I tried oil blackening the head of one to try it out. It looks good. I'd rather not spray over the screws.

Done a great job there Dave...

Thanks Rod.

Progress is being made. The whistle connecting pipe is done. The whistle is installed. The gas burner mounting is arranged. The sight glass drain pipe is fitted.

I wanted to lower the lubricator lid as it sat too high, I think I forgot about the thickness of the o-ring. It's soldered to the buffer beam spacer, so I decided to skim a bit off the top in the lathe.

That looks better.

Big steam test today, stationary steam test, to test the whistle. Complete failure, the whistle didn't work at all. However, before that, I found a few things that weren't sealed, just screwed together and forgotten about. I lit the burner with the suction fan on and closed the firebox door, all good. When there was some pressure the steam blower took over, only a very small draught was required to keep the fire going the right way. That was very pleasing.

The butane gas cylinder couldn't cope with the gas draw-off in the chilly NZ winter conditions and the pressure fell right away. I shook the can expecting it to have run out of gas but it hadn't

Well, I had another test of the whistle, it's definitely no good. I'm going to make another, hopefully it'll sound as good as Tom's on his 5" Metre Maid


The leaks are all sorted. The boiler clack valves are sealing well, and water was pumped into the boiler via the Goodall valve. Pumping in water low down seems to have less impact on the pressure than high entry locations like on all my other locos.


The steam blower is delightfully quiet in use


The fire blew out a couple of times with the firehole door closed. The burner won't be able to withstand the engine's exhaust draught. I might make an exhaust extension to the top of the chimney, the steam plume will benefit


The gas cylinder was placed in a warm water bath, I've never heard the liquid vaporising before, the gas performance was really good

What's up with the whistle Dave?

I could send you the dimensions of mine for you to scale down?

It doesn't work at all, the tyre pump test video wasn't impressive. I should copy the large De Winton's that's a lovely and powerful whistle

I should have known it was no good from when I tested it with a pump

I am no expert on Whistles but it sounds to me that the poor whistle is not resonating unlike the Dewinton one. I believe the length of the whistle is an important factor so I would compare it with the de winton one. DJB Engineering do one with a resonator chamber to get a deeper tone. Living within earshot of the WSR we do hear quite a few different ones. When Bittern was visiting Marion commented that ones got a funny whistle

Don

And don't forget that a whistle used on air will not sound/perform the same when used with steam. When I used to make whistles for larger 3.5" gauge engines I could spend ages experimenting to get the sound I wanted and when making the even smaller devices for 16mm engines the problems are even worse.

Thanks chaps

Yesterday I had a look at the good whistle, this is what I found; a well-relieved gap plug and a lovely solder filet I disassembled the whistle and made some modifications; enlarged the steam gap and relieved the excess material.

Before After Before soldering the gap plug back in I noticed that there were uneven gaps on the front end, I expect that it wasn't properly sealed and leaking

Soldered the whistle gap plug back in, when tested with my finger over the other end the whistle is much improved.

Phil is right, testing components on air and steam may not produce the same results (steam is wet when it cools).

tom_tom_go wrote: ↑Wed Aug 07, 2019 8:56 am Phil is right, testing components on air and steam may not produce the same results (steam is wet when it cools).

We've only heard your whistle on compressed air Tom...

Here's the whistle after soldering being work hardened in the ultrasonic bath to give it the crispest sound

My whistle could sound like a wet fart when running on steam!

Hopefully not though as the whistle design isfrom the original plans and there have been hundreds of this type built.

The next step was to make a Goodall valve, I had been borrowing one from the large De Winton. I took down the dimensions. I'm not using an o-ring.
I reused a boiler pressure test blanking off plug, drilled it through for 3/16" K&S brass rod and silver brazed it in.
Finished valve
Fitted

Great job on the Goodall valve Dave. It looks a big improvement on the original dare I say.

Have you tried your whistle yet mate....let's hear it please...

The valve is very similar to the Roundhouse type.

tom_tom_go wrote: ↑Fri Aug 09, 2019 9:04 am The valve is very similar to the Roundhouse type.

Great minds I think Tom

FWLR wrote: ↑Fri Aug 09, 2019 8:44 am
Have you tried your whistle yet mate....let's hear it please...

Here we go Rod



It wouldn't work on steam yesterday. So today I had a brainwave, try it on compressed air (car tyre) and at a low rate it sounded fine then and then rapidly blew out as the supply was opened up. Ah ha, I needed a restrictor. A piece of 1/16th tube was placed inside the whistle's 3/32" inlet tube and Hey Presto! It worked at all flow rates. The steam test has the restrictor fitted. The car tyre is at about boiler pressure - 30 psi, it just needs pumping up afterwards