On my Simplex I had a radiant super-heater - it poked up into the top of the firebox. The tubes were stainless steel as was the return block/bend (as in the Simplex book). The stainless steel was brazed by a friend and I silver soldered copper to the stainless at the smokebox end which itself was silver soldered into the wet and dry headers. I don't think that even with the radiant super-heater you dry much of the steam, so I wouldn't worry about the slide valves, all they need is lubrication from the steam oil and whether it is wet or slightly damp makes little difference. When I was building my Simplex the debate wasn't about damaging slide valves, it was whether or not in a 5" gauge locomotive that the super-heater had any effect anyway! Cheers Peter Does that make sense? Cheers Peter Gmx22@xxxxxxx wrote: > Hi all, I don't normally write much here but do read with interest most of > your comments. I am getting on well with a simplex but can't seem to get the > super heater right. The people I have spoken to have two schools of thought. > 1 > because it has slide valves Don't use a radiant one something to do with wet > steam being better. make it out of copper. I have just come in from the > garage having turned another peace of copper tube into scrap, lots of > heating and > i just can't get the tight bend required to make it look neat. Other school > of thought is make it radiant using stainless and use thinner tubing 22g I > think. any thoughts on how to bent copper tube or where the hell do I get > stainless from, tried GLR and the guys a Polly. I have seen lots of super > heaters > made out of SS and look neat with perfect bends but nobody can tell me where > they got the stuff. > I have a tube bender but the radius is not small enough and of course it is > metric 10mm and I am using 7/16 18g copper......... well I was! I know you > will probably think how has he got this far if he can't bend copper tube but > things have gone very well up to this point, I just can't afford to keep > throwing copper in the bin. > Great site keep up the good work > Keith > > > > > > MODEL ENGINEERING DISCUSSION LIST. > > To UNSUBSCRIBE from this list, send a blank email to, > modeleng-request@xxxxxxxxxxxxx with the word "unsubscribe" in the subject > line. > > MODEL ENGINEERING DISCUSSION LIST. To UNSUBSCRIBE from this list, send a blank email to, modeleng-request@xxxxxxxxxxxxx with the word "unsubscribe" in the subject line.