Scott Boiler

[granath]

Hello all!

I've started getting some material for the Scott boiler that I'm going to build for my 2cyl steam engine.
I've talked to Sandy (i haven't heard from him in a while now but i hope he is allright!) about the boiler and he recommended a 65mm tube for the main barrel but I'm having a lot of trouble getting that in Sweden i can get 54mm OD and 70mm OD so it's a big gap there.. so either i go with a 54mm barrel and maybe make the boiler longer? och i go with a 70mm tube 2mm thickness that i allready have. or i take the 70mm tube and slice it open and solder it together and make the OD 65mm.. if i should go with the 70mm tube witch should be the easy way, should i make the boiler shorter? i would make the boat as small as possible.. but of course i don't want any balance problem

if anybody could give me some input here it would be mighty appreciated!

Best regards// Victor

[steamboatmodel]

I would go with 70mm OD, It will give you a bit more volume for water and steam.
Regards,
Gerald.

[granath]

Thank you for the reply! yes i agree since it isn't that big difference and as Sandy explained to me this was a fast steamer so it will need to have a waterpump for watersupply a little bigger diameter should only be positive!

well it's about time to start building then he he

[granath]

Hello all!

This have been a while. well, i actually started building the boiler about a year ago.
Back then i cut the main copper barrel to the correct length, i cut and bent 17 piece's of a 6mm copper tube, drilled 34 holes using a milling machine. i made all the bushes out of bronze, did a press jig to make the ends of the main boiler tube, and i silver soldered the 17 pipes. then it kind of stopped....

For a year! but now I'm back on the horse. I have resoldered all the pipes because it was like the Niagara falls underneath it if you poored water into the boiler, i have soldered the ends to the main barrel, and i have soldered all the bushings and stays.

however i have had some problems with my soldering but this week i made a pickle bath and let the piecec be in there for and hour or so and results immedietly, so easy! earlier i used a sand blaster to clean the flux and oxidation but i think that was the problem the sand didn't reach to the places that lacked the silver soldered and they became uncleand and then i redid the soldering proces the soldering kind of stayed away, but after the pickle bath the soldering became so much better.

today i got my hands on some Brass Hexagon 13mm really cheap so that was good, and quick home and started to do the connections and fittings for the pressure gauge, so i did them and soldered it with some 5mm copper tubing. and it got pretty nice i think.

Now a pressure test is next on my to-do list.

and here is some pictures!


Boiler before drilling



After soldering



After pickle bath



Top view



Bottom view



Boiler with todays work, gauge and home made syphon fitted



Same as last one, diffrent angle



Best Regards// Victor

Ps. The next update will come much faster then last time Ds.

.

[derekwarner_decoy]

Hi PD's...... Victor....looking good...but a few questions.....

a) what size & threadform are all of the bronze bushings?....they appear to be course pitch...most comercially built model boilers appear to have a combination of 1/4"x 32 tpi, 3/16" x 40 tpi, 5/16"x 26 tpi & 5/16"x32 tpi to suit standard fittings [water gauge, steam fittings etc]

b) pressure gauge - you must install or bend a substantial syphon in the line to the gauge to enable the steam to condense [to water].... the gauge should not be subjected to direct steam......

My example gauge syphon is attached.......Derek

[granath]

Hello Derek.

All bushings are made in MM sizes and the threads are m10, m8 and m6. but since i will do my own safety valve, water gauge, boiler feed pump, on off valve's etc. i will not have a problem with this. i did this on purpose since I'm not really a fan of non metric threading, one reason is i don't have as many taps, drills and reamers in those dimension, and if I'm going to make all the stuff that is going to be attached to it wouldn't mather.

Of course you are right about the siphon Derek! thank you for that, but i think this one should work for the pressure test, and then when i have built my vessel i will bend it correctly, I'm planing to have a hatch into the deck that you can lift to check the pressure without taking the whole upper structure of.

// Victor

[R.G.Y.]

Well done Victor. Really good to see someone building a boiler, instead of paying mega bucks. R.G.Y.

[granath]

Thanks R.G.Y, yes i like to do the things myself, and the prices here in Sweden is ridiculously, so i hope this will make a good boiler for my twin cylinder marine steam engine (not completed yet but not to far away)

But all credits should go to Sandy, it is his design and he have helped me with tons of questions and calculations.

// Victor

[steamboatmodel]

It looks great.
Mine is still on the Round Tuit shelf, too much on the house repairs and Honey do list.
Regards,
Gerald.

[granath]

Thank you for the good comments, it gets you motivated, what are you building Gerald?

// Victor

[derekwarner_decoy]

Hi PD's......... ...Victor...I see you have mentioned 'Sandy' on two occasions....could this be the  Sandy Campbell? ...if so then you have a great mentor & tutor .....Derek

[steamboatmodel]

Thank you for the good comments, it gets you motivated, what are you building Gerald?
// Victor

Hi Victor,
I have a modified Mabel design with the wilesco D48 engine, that I have been playing around with different boilers, its on boiler vers 4 now with 5 and 6 still to be soldered and finished. I am also working on one of the Midwest Fantail launches, which I am installing a Kitchen Rudder. Now that we are getting into spring the warmer weather and more daylight might get things going.
Regards,
Gerald. 

[granath]

Derek, yes it is Sandy Campbell I'm talking about, but i lost touch with him, emailed him last week but no response yet, hopefully that will change.

Sounds intresting Gerald, you should upload some pics pics is allways welcome.


// Victor

[derekwarner_decoy]

Hi PD's.......Victor ...Sandy Campbell was a member of great interest & importance on PD's in 2005>2007....many of his superb articles are in our archives...& I just loved his sense of humour...

Sandy sent me an email saying ......'your ACS VB2 boiler will need a serial number.........can you tell me the Official Number of PS Decoy?' ....I responded ON 74682...& that is now Decoys boiler serial number

Not only very knowledgeable....but a great man to deal with ....sadly I too have lost touch ..........Derek

[granath]

Hello Derek, all true about Sandy a truly great and nice man.

Not a bad idea about the serial plate, looks really good.

// victor