RickyT | 31/08/2013 16:52:02 |
19 forum posts | I have been building a 5" gauge Manor to Martin Evans' design for more years than I would like to admit. I have a John Ellis boiler which is some years old and have reached the stage where I have begun work on the various backhead fittings. Some of these (most notably the firebox door assembly and the atomising valve for the sight feed lubricator) need to be fixed to the backhead. My question is how this is best done. I am not aware of any solid stays in convenient positions. I am reluctant to drill into the backhead itself for obvious reasons. I know that some builders attach these items to a separate plate on the back of the firebox, but that still leaves me with the question as to how the plate itself is then fixed. I'd be grateful for any advice people may have here. |
Phil Ashman | 02/09/2013 12:42:42 |
33 forum posts | Ricky, I'm also building a Manor, and have a John Ellis boiler. I fixed my firedoor assembly by tapping directly into the boiler, fixing it with stainless steel screws. I'm not sure if this is correct, or whether I should have used bronze screws as Michael suggests. The backhead is certainly not as thick as 3/16", nearer to 1/8th I would say, but the fixing seems perfectly sound. Phil |
RickyT | 02/09/2013 21:37:14 |
19 forum posts | Many thanks for the suggestions. I was working on the basis (although only a working assumption) it was 1/8" copper as it seems to have been used so liberally elsewhere. If bronze is indeed the best material to go for, would the screws then need fixing with a solder (comsol?) or adhesive of some description? |
julian atkins | 02/09/2013 23:44:11 |
![]() 1285 forum posts 353 photos | hi ricky, firstly you need to check with your club boiler inspector what is acceptable. i think most boiler inspectors will be ok with a few bolts tapped into the backhead with bronze or non-magnetic stainless bolts. if your club boiler inspector is 'iffy' then use michael's excellent suggestion using the backhead cleading (which you will have to make as it isnt on the drawings). the bolts shouldnt need comsol and if the threads are ok (as they should be) no sealant either. the atomising valve on the martin evans/fred cottam hydrostatic lubricator is in my view quite unnecessary. i have a simple stop valve on the oil delivery pipe actuated by the regulator quadrant as can be seen in one of my pics in my album. also the martin evans nozzle in the sight glass has far too big a hole in it. No.76 or No.78 will give much better results. cheers, julian |
RickyT | 04/09/2013 22:29:48 |
19 forum posts | Sounds like bronze screws is the answer then, although I'll only have 1/8" thickness in which to cut the threads. I will run it past the boiler inspector first as he will ultimately call the shots when it really matters. Many thanks all. |
KWIL | 04/09/2013 22:53:32 |
3681 forum posts 70 photos | Is it possible that you could insert and silver solder into the backhead blind tapped PB bushes. These bushes would need a narrow flange to allow them to be fixed against the back face?? |
Phil Ashman | 05/09/2013 12:12:05 |
33 forum posts | That idea occurred to me as well, but I didn't try it because I didn't think I'd be able to get the backhead up to silver soldering temperature. I made up some fixings that consist of a thin hexagon flange, with a threaded piece either side. These screw into the backhead, then the door fitting is fixed to the protruding thread with nuts, the idea being that the door assembly could be removed without having to unscrew anything from the backhead. The firehole ring protrudes slightly from the backhead about the thickness of the flanges, so the door closes fairly snugly over the firehole. But in view of what's been said, I think I'll change the fittings to PB instead. Phil |
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