Small Boiler

[editor@glue-it.com]

Interesting, but with only the one picture of the “rivet anvil”, it is very hard to comprehend. A video of this in use would be explanatory I believe. Thx.

Hi, I film some video of me rivetting the towbar onto the tender, hope this helps

[editor@glue-it.com]

Finally I'm making that small boiler, this is the first boiler I've made. Although it's very small and below the size that requires independent testing (less than 3 bar litre) my plan is to hydraulically test it and do all of the normal sign-off testing that is required.



Would be good to hear from people who have experience making boilers and testing them.

[editor@glue-it.com]

This boiler is just 117mm high and you can see it here alongside the traction engine:



I have now hydraulically tested this to 2x working pressure



I used a simple garden sprayer - a small modification to the nozzle to fit a pipe. This easily gets to 100psi and I think it would get to 200psi - need a gauge.

I've written a brief article on making the boiler.

I will share more on testing as I need to ensure no issues under steam.

[editor@glue-it.com]

A simple modification to the sprayer nozzle and you have a pump that can pressurize a water volume at over 100psi - perfect for hydraulic testing





the fixed nozzle of the sprayer seals against the rear flange of the new brass fitting


I had to use cable ties to keep the pipe secure on the nozzle with the pressure

[editor@glue-it.com]

Lighting the methylated spirit burner on this small vertical boiler can be quite tricky, I made a slow-motion video to show the problem:

Note: don't try this at home

[editor@glue-it.com]

I needed a grate for the fire, but cannot cast iron and so made one from solid. This meant I needed a jig to hold the disc:



The jig was made from aluminium and it meant I could flip the part over and so machine both sides without damaging it. There were a few steps to making a cast iron grate, but it was very enjoyable. I think the finished part looks good even though you will only ever get a glimpse of this in reality.

[jdurand]

Interesting, I would have done it using square bars and welded or bolted from the back depending on need.

Surely looks solid!

I do like the look of things that are carved from a block with holes where people might not expect them.

[editor@glue-it.com]

Interesting, I would have done it using square bars and welded or bolted from the back depending on need.

Surely looks solid!

I do like the look of things that are carved from a block with holes where people might not expect them.

I probably could, but the beams are only 3mm wide and 3mm apart. Welding could be done with solid bars. Not sure I can easily find steel square tubing.

I agree, there are many ways of doing this.

[editor@glue-it.com]

I'm in the process of making two fireboxes, one for methylated spirit and the other for coal. I know, why?



In all honesty I just wanted to have a play and see. This way I can learn about firing with coal and see how hard it is with a tiny boiler. The boiler with the firebox and chimney is just 105mm tall (~4 inches). Air, coal mass, thermal mass, air draft etc is all going to be an issue. I will go through this and share my pains.

[editor@glue-it.com]

This small boiler is driving me a bit mad, I'm struggling to get the heat into it. It gets to temperature and pressure, but it takes ages considering the meths burner I'm using.

So I decided to instrument the boiler with thermocouples and to then do some measurements.



I'm using a Pico Technology measurement board and software, very easy to use. I will share the data and my analysis.