Should we be worried…?

[Paul Relf-DaviesParticipant @paulrelf-davies37806]

I’ve just watched a video ad on Facebook for what seems to be a new toy steam plant….not surprising, given Christmas is approaching.

I’m sure you’ve seen ads for build it your self engines….it’s one of these. It showed the boiler being built up – as in screwed together – from parts. This included the boiler tube itself, with the end caps held on by a through bolt and sealed with a silicone(?) ring. Yes…a fully bolt together steam boiler…!

Now I appreciate that this toy is probably designed to operate at Mamod-like pressures…and there was a pressure relief valve, but this doesn’t strike me as the safest thing to be building & trying out on Christmas morning.

Or am I overthinking this?

thoughts…

[Tony Pratt 1Participant @tonypratt1]

Personally I’m not worried about it, but it does beg the question as to what if any legislation covers this sort of thing?

Tony

[JasonBModerator @jasonb]

Plenty of locos using an o ring to seal the dome and working at much higher pressures.

Probably safer than many that have been around for years that just use a bit of silicon tube to connect boiler to engine and just let it blow off as the safety device

[noel shelleyParticipant @noelshelley55608]

I would not be unduly concerned, no worse than a small petrol engine exploding when over revved. May be an updated variation of setting the house on fire as you light the candles on the tree ? Noel.

[JasonBModerator @jasonb]

Don’t know which one was in the video but at least this one avoids spilt meths or any form of fire. What could be safer than an electric element and water.

[SillyOldDufferModerator @sillyoldduffer]

Doesn’t worry me because the pressure and volume of steam in toys is very low.

There are bigger risks!  Aged 11 it didn’t occur to me that pouring meths into a lit Mamod burner might be dangerous.  Set fire to the bed, and fortunately the coverlet was fire resistant.   I was saved because so many adults smoked in bed…

Dave

[JasonB]

On JasonB Said:

Don’t know which one was in the video but at least this one avoids spilt meths or any form of fire. What could be safer than an electric element and water.

You could even use it to drive a little dc motor as a generator and light up a bulb!

[JasonBModerator @jasonb]

Click the video link on that page and you can see it doing that, 8 LEDs

 

Expect to see another “free Energy” video shortly where the poster has added a small inverter to power the 240V element😂

[JasonB]

On JasonB Said:

Don’t know which one was in the video but at least this one avoids spilt meths or any form of fire. What could be safer than an electric element and water.

<p style=”text-align: left;”>As it says in the link, an electric kettle. Most of us have one. The heating element from a cafe type coffee machine is a good start for an electric boiler, they are designed to work at pressure.</p>

[Robert Atkinson 2Participant @robertatkinson2]

The boiler linked to by Jason is not safe.
1/ No overheat protection
2/ Inadequate earthing – M3 screw is not large enough and is not directly connected to the boiler shell, There is a painted surface and anodised surfaces between the connextion and parte that may be live.
3/ There is low temperature plastic (junction box) in the electrical connectiion “stack-up” this would not be acceptable even if it wasn’t on the end of a hot element.
4/ No proper strain relief in the mains cable.
5/ No no/off switch.
6/ No indication that it on.

Additionally the pictured power controller is clearly non-compliant and unsafe – unfused “skinny” mains plug and “universal” output connector with no shutters.

The webpage says “The boiler cylinder is provided complete and tested (certificate provided)” but the element isn’t fitted and the instructions say “Boiler assembly instructions:
1. Remove the 2 long M5 screws from the boiler cylinder to separate it into its 3 parts plus 2 O
ring seals.”

Is aluminium an acceptable material for boilers? Even unpressurised water heaters on aircraft are stainless steel.

Robert.

[Speedy Builder5Participant @speedybuilder5]

Boiler end caps held on by a longitudinal stay – common practice on marine steam boilers for this sort of boat.

https://www.steamboatassociation.co.uk/page-1854655

[Robert Atkinson 2Participant @robertatkinson2]

I bet the steam boat version of a boiler code does not allow steel boiler stays threaded into aluminium in the wet part of the boiler…

Robert.

[JasonBModerator @jasonb]

Here is a Frisbie engine from 1871. Cast Iron boiler and in this case top cap. Fibre sealing washer (don’t know what sort of fibres) and a screw to hold them together, I’ve seen them with both brass and steel screws. No safety valve not that one is needed. Just light the spirit burner and wait for it to warm up. I’ve got this down on my list of engines to replicate.

[Martin ConnellyParticipant @martinconnelly55370]

Dave, you should have been outdoors. Then adding fuel to a burning heater will only result in burning meths on your hand as my brother found out. Luckily a quick trip to the nearby tap prevented any real pain and the only thing he suffered from was a surprise. I think he was a little less than 11 at the time.

Martin C

[Robert Atkinson 2Participant @robertatkinson2]

Interestingly Chiltern also sell a gas fired version of the aluminium boiler:
https://www.chilternmodelsteam.co.uk/index.php?route=product/product&path=66&product_id=118

I can’t find any reference to the suitability of aluminium for model steam boilers and the test code only says it can’t be steel. Seems like the idea of a aluminium one is so unrealistic they don’t even think to prohibit it.

Even if the gas fired boiler was copper It appears to me that it would not meet the <3 bar/liter requirements because the water level gauge is optional and the gas supply size is uncontrolled so can’t be arranged run out before the water has boiled off.

Robert.

[noel shelleyParticipant @noelshelley55608]

My Stuart Turner Mk814 spy radio generator of 1956 has an aluminium boiler, basically a pot with a bolt on end. Has a safety valve, clack valve and water gauge with a feed pump on the engine. runs at 65 PSI. Noel.

[duncan webster 1Participant @duncanwebster1]

Many moons ago there was a design in ME for an electrically heated boiler which had an insulated electrode inside and current passed from this electrode through the water to the shell. Sounds horrendous but it was fed via an isolating transformer so the shell was earthed. If it runs out of water no current, so sort of fail safe.
Thankfully electrical safety has moved on a bit since.

An electrical engineer colleague of mine related how they used to brew up on site, drive 2 off 6″ nails through a piece of dry wood, connect to the supply and lower into cup. And there are still people who object to H&S procedures

[NealebParticipant @nealeb]

My Gaggia coffee machine has an electrically-heated boiler (element wrapped around outside) made of aluminium and I understand that these things reach something like 8bar. Noticeably suffering from internal corrosion although thick material to start with, not rolled sheet or thin tube. I’m pretty sure that it is going to start leaking at some point…

[Author]

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