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[pnr/p]

Could anybody explain the right/proper way to insulate steam pipes. I was told to use string and coat it with plaster of paris but the tellers examples looked like a cross between a dogs dinner and a building site. There are so many 'nice' examples, so how is it done please.

[anmo]

You really only need to insulate the feed from boiler to engine, there's no need to bother with any other steam pipes unless you like the appearance. I use a method demonstrated to me by the late John Woodrooffe of Cheddar Models, use fairly thick white parcel string, and attach one end with a dab of superglue. Then wind the string carefully along the pipe, anchoring with another blob of superglue at the other end, and that's all there is to it, no intermediate fixing needed, and it's all that Cheddar ever did on any of their engines. I've got ten year old examples that are as good today as when they were first done, and the only change is a quite pleasing darkening of the string at the hotter end. I've seen very few examples where anything like paint was applied to the string, I'd say it would reduce the insulating properties, and make it a pain if you wanted to replace the insulation. I've never heard of that plaster of paris method, but it sounds very messy and rather a bad idea to me.

[Scottie]

I don't think it's possible to improve on that response.

Scottie

[anmo]

I don't think it's possible to improve on that response.

Scottie

I've just thought of a way it could be improved, I should have spelled 'Paris' with a capital 'P'.

[HS93 (RIP)]

I use the above method ,but I have seen people use the above and then wrap   PTFE /GAS  tape over the top it makes for easy cleaning  Peter

[tobyker]

I'd string along with that advice. Act accordingly. Unless of course it's a wind-up.

[Doc]

The purpose of insulating steam pipes is to keep from being burned by them, and to retain heat.  Since the amount of heat loss depends on the length of the steam pipe, and since that length is usually not something you really have to worry about with the typical model, keeping from being burned (or starting a fire) is the 'biggy'.  Basically, it's a "whatever looks good/right" thingy that doesn't contribute to burning you, sort of...
 - 'Doc

[kayem]

Don't really agree there Doc. It's true that the length of a steam pipe is an important factor in the amount of heat loss, which obviously should be kept to a minimum in the interests of efficiency, but there's rather more to it than that. Look at it this way, an uninsulated steam pipe between boiler and engine will burn stray fingers, ergo heat is being lost from the pipe. If the pipe is lagged with string, it won't get anything like so hot, and it won't burn your fingers, so much less energy will be wasted burning fingers on the way. The likes of Watt, Stevenson, Newcomen and Trevithick agreed with me (though I never met them of course). They always lagged steam pipes on their engines, as can be seen in old photos, as well as in museums today.

[Colin Bishop]

They always lagged steam pipes on their engines, as can be seen in old photos, as well as in museums today.

And what did they use? - Asbestos!

[kayem]

They always lagged steam pipes on their engines, as can be seen in old photos, as well as in museums today.

And what did they use? - Asbestos!

You're suggesting no doubt, that if they'd used some alternative lagging material as approved by the Health & Safety Executive, they would all still be alive today?

[Colin Bishop]

No, don't think so, they'd all probably be dead of Mad Cow Disease and I think I'm in danger of hijacking the thread so I'll stop now.

[roycv]

Hi all, I was leaving this to be answered by steam friend Malcolm.  So this is what he does!
Use ordinary string, and wind it around the pipes nice and tight and neat.  Then get some white very thin PTFE joint sealing tape and wind this neatly and firmly around the string progressing to the end.  The heat seems to shrink the tape into place and it can be wiped clean or replaced as necessary.
regards to all, Roy