boilers ?

[R.G.Y.]

The latest had a test found 2 leaks had to re solder! OK now.

[R.G.Y.]

latest. showing how the plant will look. 

[derekwarner_decoy]

Hi PD's........R.G.Y. ....do you line the interior surfaces of the boiler casing with refractory material for improved ...... thermal heat retention?....Derek

[R.G.Y.]

Yes Derek, I am going to use Themalight building block cut into thin strips. Because its cheap and available. Also the stainless shield will stop the heat going st right up the funnel. Geoff

[derekwarner_decoy]

Hi PD's...& thanks RGY....this is a very interesting build thread 

Your semi unconventional design.....but conventionally fired boiler will attain approx 150 degrees C surface temperature on the top singular shell

We see the stainless steel heat deflector plate @ the top...........however you could consider a few layers of aluminium foil over the Themalight material  .....the aluminium sheet will blacken even at these low temperatures, but look preferable to a blackened Themalight surface......Derek

[R.G.Y.]

Derek, The last photo I posted is minus the mild steel top and side covers. If you go back to post 45 top photo, you can just see the top cover with the funnel attached and the screw holes for the sides. I have to make a new top as the funnel was to near the safty valve!! Plus the funnel needed for the model I have in mind is just forward of the paddle shaft.  This is another advantage with a water tube boiler, the funnel can be possitioned where best for any model. If I change my mind and build a differant ship just replace the top. Thanks for the interest.

[R.G.Y.]

Just waiting For the gas jets, then I can make and install the burners, and complete the insulation. By the way the pipe and fittings are made for refrigeration plants and are stronger than domestic water pipe. This is for Mat I know he was worried about the use of any old rubbish.
In the photo the new top cover needs a coat of paint (wood burner), the white paint from the washing machine just went brown when the gas torch was played on it, so that's OK. The wife hasn't notest the hole. Geoff

[Eddy Matthews]

Now it's all put together it looks like a very neat unit Geoff, well done!

Regards
Eddy

[R.G.Y.]

Thanks Eddy, here is the complete plant. Now the difficult part finding someone to give me a certificate. The local model engineering club tester doesn't want to know not a railway engine!! and what to but it in. Geoff

[steamboatmodel]

Hi Geoff,
Over here in Ontario Canada you would not need a certificate for a boiler that size. Can you do a video of it under steam?
Regards,
Gerald.

[R.G.Y.]

Gerald, sadly there are to many rules here. As I will have to sail in a public place I will need insurance for that I need the certificate. The insurance company will do it for £ 450!! This size boiler need only be tested the once. Visited B.C. eighth times plenty of sailing waters there. Is it the same in Ontario. The engine has run on air but still waiting for the gas jets for the burners. I could play a blow lamp on it I suppose. But haven't started on a boat yet so no rush. Geoff 

[R.G.Y.]

The jets have arrived. Change of plan only one burner but holes on each side. See below. Cuting and instaling insulation. Driling the burner and fireing up the flames just visable in the last photo. Geoff

[Underpressure]

Geoff, I have been following this thread with interest, and I am fascinated to see the boiler and engine working. I am not totally convinced you have managed to make a lower profile boiler, but you certainly have taken a different approach and one that almost anyone could also take, brilliant.

Neil

[R.G.Y.]

Neil thanks for your comments. You are right the profile of the boiler casing is higher if anything. But the center of gravity I believe is lower than a yarrow 2 small tubes at the bottom and most of the water in the tube above. If you study a scotch boiler most of the lower quarter is narrow and taken up by the fire tube, not much weight of water. As you say It is simple to calculate no stays narrow tubes so thinner copper can be use with complete safety. Some domestic pluming pipe can be very thin so beware, the pipe used for refrigeration is best as it has to withstand up to 40 bar.  There is extra work in the case but is required to be accurate . Still have the insulation to complete and I'm still playing with the burner, drilled  out the jet .3mm and extra 9 holes in tube, 29 total.  running soon, but won't be(allowed) in the workshop over the next few days.Geoff

[R.G.Y.]

That should read. case need not be accurate. Geoff