New to group, New to boiler making.

[Nickademusss]

Hi all, I recently came across a castings kit for a Stuart beam engine, my Dad is a doing the machining for me, I am doing the finish work.

I would like to run it on live steam and have found two kits that look like they would do the job, the PM research boiler 1 and 2.

I have always loved how the vertical boilers look, would the boiler number one have enough capacity to run the beam engine?

If not does anyone one else make a kit or have a set of plans for a vertical boiler that would?

Thanks in advance for any help you guys can come up with.

 

[Springbok]

Hi Nick
Firstly has you dad access to silver soldering/braising kit as a boiler should NEVER be soft soldered that is a disaster waiting to happen, as to the type of kit I have never made anything that small please do a bit of research also I am sure that someone on this forum will help there are other forums in the UK also. Good luck and it is lovely to hear about a young person getting interested in ME
If you want I will post you the other forum addresses.

Bob

 

[dalem9]

Hi Nick You can conpare the cylinder size of your engine to the ones at PM to see if it will work. Welcome . Dale

 

[tel]

I'm not familiar with the P M R boilers, but the Stuart Beam's 1" x 2" cylinder is fairly steam hungry. Well, mine is, at least.

 

[dalem9]

Yea I an thinking the bigger one to , i have it and it is a nice boiler.Dale

 

[Mainer]

To echo what Springbok said:

I assume the boiler plans will explain the need to assemble the boiler by silver brazing (a.k.a. silver soldering) and not soft soldering, and to hydrotest the boiler to 2x the intended working pressure before trying to steam it. If the plans don't tell you about those things, find out about them elsewhere and be sure you fully understand what needs to be done to ensure a safe boiler. Even a small boiler at 60psi is a potential bomb that could ruin your whole day, if not life.

 

[mklotz]

Having built the PMR vertical boiler, let me point out that it is supplied with soft solder and the instructions do not specify any silver soldering. The boiler tube plates are secured to the shell with rivets and the soft solder is used only as a sealant. The fire tubes are soft soldered to the tube plates. I hydro tested mine to 120 psi and have fired it numerous times with no difficulties. However, I usually run engines at 20-30 psi.

I think it would have trouble keeping up with a 1 x 2" cylinder.

I've never seen the PMR horizontal boiler in the flesh so my remarks should not be applied to that boiler.

 

[Maryak]

Attached is a spreadsheet which may help you determine if the boiler is big enough.

Best Regards
Bob

View attachment Boilercalc.xls

 

[Nickademusss]

Thanks guys, I will be building the boiler, Dad is completing 90% of the engine (he has the tools and the time).

I will make sure I use good silver solder, The larger PMR boiler says its comes with it, but I will verify.

So no other companies make a kit? Whats a good easy to build scratch made boiler?

Thanks again!

 

[steamboatmodel]

Check as to whether it is true silver solder of silver bearing solder (stay bright 5%silver).
Regards,
Gerald.

 

[mklotz]

Check as to whether it is true silver solder of silver bearing solder (stay bright 5%silver).

As I said in my earlier post, it's soft, silver-bearing solder. It's made by Harris and melts at about 430 degF.

 

[Springbok]

There is no such thing as a soft silver bearing solder at the temperature that you state
or is this American terminology. check out the cup alloys web site. This is a young persons life we are adviseing on
and could be a disaster waiting to happen.
Sorry to be so grandad'ish but my youngest is 16 rest up to 20's so am very protective of our young and up and comeing engineers

Bob



Merry Christmas

 

[bob ward]

Get hold of a copy of the Australian Standard for miniature boilers, lots of very useful info there

http://www.pnc.com.au/~wallison/AALS/AMBSC/AMBSC.htm

 

[mklotz]

There is no such thing as a soft silver bearing solder at the temperature that you state
or is this American terminology. check out the cup alloys web site. This is a young persons life we are adviseing on
and could be a disaster waiting to happen.
Sorry to be so grandad'ish but my youngest is 16 rest up to 20's so am very protective of our young and up and comeing engineers

Harris sells its silver-bearing solders worldwide so I don't think it's "American terminology". Check it out yourself here...

http://www.stoodyind.com/Catalogs/FISC/05catpg372.pdf

Also, I'm not "adviseing" (sic) on the use of soft solder for boilers. I'm merely pointing out that this is what is supplied with at least one of the kits being discussed.

 

[steamboatmodel]

There is no such thing as a soft silver bearing solder at the temperature that you state
or is this American terminology. check out the cup alloys web site. This is a young persons life we are adviseing on
and could be a disaster waiting to happen.
Sorry to be so grandad'ish but my youngest is 16 rest up to 20's so am very protective of our young and up and comeing engineers

Bob



Merry Christmas

I think what Marv (mklotz) and me are trying to point out is that PM Research includes the silver-bearing solder in its kit. The boiler is intended to be fired in the same way the Mamod toy boilers are fired with ether gelled alcohol or Esbit tablets. If it is fired in that style and the pressure is kept low (below 30psi) it may be safe. Personally I would silver (Hard) Solder it using Easy-flo or something similar. http://www.jm-metaljoining.com/applications-pages2.asp?pageid=5&id=96
Regards,
Gerald.

 

[Springbok]

OK got the wrong end of the stick, did not realise it was so small as to use these to fire it. The smallest that I have built is a 5"g Thompson B1 Springbok and the largest a 7.25 Hunslet that weighed it at 3/4 ton dont know metric equivelant.
At now around the 70s I am very protective of our young engineers, My youngest grandson (16) has just completed a Sterling hot air engine in my workshop.

Joke; I have wanted to say this for sometime "Put your tongue in you will catch bugs" and not the computer kind.

Seriously everyone have a nice Christmas I will be escapeing down into my workshop whilst about 60 odd will decend on the house.
And therein dissapears the drinks cabinate

Nick I am sure that your father will advise you as the best thing to do.

Bob ;D ;D ;D

 

[steamboatmodel]

Just so everyone knows the size of the Boilers in question I have copied this from there site.
PM Research BLR-1 Boiler,
http://www.pmresearchinc.com/store/product.php?productid=3111&cat=7&page=1
The firebox is 3" diameter x 2 1/2" high. The door opening is 1 1/2" high x 2" wide. The water space is 3 1/2" high. There are 13 flues which are 3/8" diameter, 61 square inch heating surface, 20 cubic inch volume.
We recommend "ESBIT" dry fuel tablets to run this boiler although other heat sources are possible. We also recommend the use of distilled water.

PM Research BLR-2 Boiler,
http://www.pmresearchinc.com/store/product.php?productid=3112&cat=7&page=1
The door openings are 1 1/2" high X 2 5/8 wide. The water space is 3" dia. X 8" long. The fire box is 3" wide, 7" long X 1 3/4" high. It also has a cleanout door that opens to access the flues. It has a 5/8 dia. flues, 127 square inch heating surface and 44 cubic inch volume.

The second one at over twice the heating surface would be the better steamer, but the first one would look beter in a boat. The safety valves they sell come pre set "
They are set to blow at approximately 60 psi."
The silver solder as mentioned previously looks to be Stay Brite Silver bearing solder and not a true hard silver solder.
Regards,
Gerald.

 

[Nickademusss]

I have ordered the BLR-2 kit, thanks for the advice!

As to the solder that comers with it, I understand that it has a low melting point of 450F or there about's and everyone who has posted thinks this is to low, what melting point should I look for? Is 600F good enough? Also does it braze in like doing copper plumbing as in residential ? Or will I need a hotter torch tha a propane one?

Sorry for the newbie questions, but I havnt built one before.

 

[Mainer]

If it is supplied with the kit, presumably it is considered suitable for the boiler design. In the absence of other information one would use silver solder (more properly "silver braze") with a melting point of around 1200F. For that you need a BIG propane torch or air/aceetylene or air/MAPP. High strength silver-bearing solder that melts at 450F will be a lot easier to deal with if in fact a responsible designer has verified its suitability. 60 PSI steam is around 300F, so you'll be 150F below the solder's melting point. Do you feel safe with that?

 

[Nickademusss]

If it is supplied with the kit, presumably it is considered suitable for the boiler design. In the absence of other information one would use silver solder (more properly "silver braze") with a melting point of around 1200F. For that you need a BIG propane torch or air/aceetylene or air/MAPP. High strength silver-bearing solder that melts at 450F will be a lot easier to deal with if in fact a responsible designer has verified its suitability. 60 PSI steam is around 300F, so you'll be 150F below the solder's melting point. Do you feel safe with that?

After looking at the build more in depth I dont mind the solder that comers with it, the whole thing is riveted as well as soldered.

Thanks for the response.