Copper boiler

[MattMaie]

What's the general procedure for building a model boiler out of copper? What sort of safety procedures need to be followed, how thick does the material need to be etc. And what kind of pressures can be withstood? I know that copper is typically used for small engines, 1/4 scale or less.

 

[steamboatmodel]

The fist thing you have to do is read some of the books on boiler making, there is a list in the second sticky of this section. I would then go through the first sticky to try to find out what the legal regulations are in your area. then go through the construction threads in this section. Then find a Model Enginnering group near you and join it. You then have to find a proven design that you feel you can build, do not try to build one of your own design yet. Having used a proven design you should not have to worry about the material thickness calculations but I would do then just for the practice. Haveing made the boiler you now have to test it.
Regards,
Gerald.

 

[gus]

I found this book to be very informative. From here I made copper boilers with peace of mine.
There is another book on steel boilers.

If you are planning to make copper mini boilers, silver brazing skill is a requirement. Making your own dished ends to cap copper shell is another requirement.
I am not aware of equivalent in USA and UK.

 

[bazmak]

i have built a 3/1/2" loco and the boiler.It was 4" dia and 1/8 thk copper
All design was already done so did not have to worry.It still had to be tested by a proffessional body and given a certificate.Not easy or straightforward.
You must remember that that the loco is scaled down in everything except PRESSURE. It will run at nom 200 PSI as same as the real version and will need to be
hydraulically tested at least twice that by a proffessional body.Regards Barry

 

[gus]

i have built a 3/1/2" loco and the boiler.It was 4" dia and 1/8 thk copper
All design was already done so did not have to worry.It still had to be tested by a proffessional body and given a certificate.Not easy or straightforward.
You must remember that that the loco is scaled down in everything except PRESSURE. It will run at nom 200 PSI as same as the real version and will need to be
hydraulically tested at least twice that by a proffessional body.Regards Barry

Hi Barry.
Good advice. I was informed that the voluntary inspectors for your local clubs are very professional and helpful. W/o a certification from a recognised club inspector,you cannot run your loco on their tracks. This good practice has resulted in ''zero'' boiler explosion and fatal injuries.th_wav
Hydrostatic Test at 1.5 times the Design Pressure will confirm the structural fitness of boiler from parts to silver brazing. The safety valve is most important to prevent over-pressure and explosion. Same must be sized to match boiler steam capacity generated. Undersized or malfunctioned safety valve is deadly.
I have NorthThumbrian Loco drawings and wheel castings gathering dust.No plans yet to build.Too many projects and not enough time.:rant:
My mini Tractor Engine is gathering dust too. Will clean up and it another run sometime later.

Take Care.