The last of my acquisitions in Newark was a battered old 8R from Shagratork’s collection: It fired up with little effort and improved after a bit of a clean: The case however needs a lot more attention - more than anything I have done so far: So… easiest question first. The electrolysis tank will make short work of cleaning off the crud and old paint on the case but what is the best way to clean up the heatshield / chromed tank? I’m assuming something more than a warm detergent wash and hand polish is needed but don’t want to do more harm than good. Next, is removing the pin from the lid hinge do-able? If so, are there any tricks / techniques that are recommended? My google-foo can only find videos about door hinges. Finally, I will have a go at fixing up the tears in the lid. Should I be thinking of brazing a small plate across the tears or might brazing the edges back together work? Any and all advice is most welcome! -R
I might consider a strip inside the lid running full width brazed in place once the case is stripped. Or the same but pop riveted in place would be less of a challenge but less aesthetically pleasing. The tank and heat shield are a challenge and decision aren’t they clean up and live with or find a donor or get stripped and re nickel plated which would be expensive. I will watch with interest. Cheers Nick
Hi @nmp I’m not too worried about getting the tank / heatshield gleaming, just to tidy it up. This will hopefully be a ‘user’ (like most of my stoves) not a display piece. The case is the challenge. Rivetting did occur to me, but I don’t (yet) have the means. If I go the brazing route do I need to worry about the hinges coming loose from the case, try and braze them in place first then braze a strip with a lower temperature alloy, or ‘sandwich’ them in place by brazing a strip across them? Am I wasting my time thinking I can remove the hinge pins? -R
@IRM Are the hinges still attached to the case? It's a bit hard to make out. The were spot welded to the case, in the last photo you can make out the three round marks approx 1/8" diameter. This is 'proper' welding so will not melt at brazing temperatures. Regards the cracks, best practice is to drill a small hole at the very end of the crack, to stop it continuing further., however that would not be vital in thsi case as the stresses are not enormous. You could try panelbeating everything flat, then brazing up the cracks and holes (if drilled). A reinforcing patch would probably be worthwhile in addition, the steel has obviously thinned from corrosion. If you do need to braze the hinges plus crack and possibly plus reinforcing plate, it may well be easiest to do it all in one go- shape everything to fit, clean everything up, flux, clamp it all in place by any means required, and do it in one heat. I wonder if there was an undlerlying cause for the lid to get so bad, prehaps a bit of misalignment, or resting something too heavy on one or both parts of the case in use?
The story so far… 3mm holes drilled, one a little short - the hinge fixing on the other side got in the way. I’ve had a stab, no, a bash, at straightening things up: Now more brazing novice questions… Nick suggested a reinforcing strip along the inner surface. If I heat from the outer side and apply the alloy rod along the inner edges, how do I ensure the brazing alloy flows to the cracks? If I do it the other way around my (utterly inexperienced) gut feeling is that the alloy will flow through the cracks / drill holes and under the reinforcing strip. Am I on the right track? The strip should presumably cover both hinge fixings and so there will be a gap between it and the case. My understanding of the Soldering and Brazing book @Blackdog recommended suggests the above two points are somewhat contradictory. The former leans towards relying on capillary action and an alloy like silver-flo 55, the latter towards something that’s less reliant on capillary action and more of a gap filler, like silver-flo 302. Would putting the reinforcing strip on the outside be easier? Am I on the right track, totally wrong, or totally over-thinking this? A more straightforward question… how do I clamp all this together? I have a few G clamps with plastic ends, so I need to get something. What should I be looking for? With the case still in one piece it’s not straightforward. -R
Braze will flow through any gaps towards the heat source, so the best bet if you make a repair patch on the inside, would be to heat from the inside, apply filler rod to the cracks and holes from the outside, and add more filler rod if needs be inside to ensure the repair strip is well attached. if that makes sense? Ideally a reinforcing strip on the inside would not be fixed over the top of the hinges, only to the tin, with cut-outs for the hinges. Braze would then flood and join tin, strip and hinges in a solid block. A reinforcing strip on the outside would be far easier, and more effective on the outside, covering the area of crack, the hinges and surrounding metal. It depends whether you want things to look original with the stove closed, or in use. Sorry I'm not really qualified to comment on disassembling the hinge... But it looks to me as though you'd have to bend up tabs to release the pivot wire. This would be fine if you normalised them by heating to red and allowing to air cool. A lot of faff if you can clamp without... Clean the steel to within an inch of its life first, and rusty areas will not take the braze. .....If I've missed anything keep asking, I'm sure others will have ideas too.
Do you have any mole grips the plastic ended G clamps could well be a problem when Brazing. Or drill and screw the patc in place while you braze it but Mole grips would be best.
I'd go one further and say plastic will certainly be a problem with brazing. The ideal tools for this particular clamping job job are 'Welders 'C' clamps', cheap, can be had in a variety of sizes and useful for lots of other things too. But not a solution if you want to get the job done today! Clutching at straws here, do you have any chunks of metal (large nuts?) which could go between workpiece and plastic? maybe with something insulating too?
There’s no rush. I have ordered a couple of largish c-clamps. I will spend the time thinking about placing the strip inside vs outside. I have mole grips however having tried them out I don’t see a way to use them that doesn’t get on the way. Thank you both for the pointers. -R
The age old problem of metalworking... So many jobs require something to be purchased especially, it takes a lifetime to build up a workshop where one can tackle *nearly* everything... There is always the option of selling tools or equipment on after the job, but it all seems to end up being kept in case it's needed again...
I think of tools as an investment. It’s when the collection grows to the point that you need a bigger shed / garage / house they get really expensive Having slept on it, I am going to put the reinforcing strip on the outside. No point making it harder than it needs to be when I’m just starting out on brazing. I will do a few practice runs this week before I try the real thing. Any thoughts on 0.5mm vs 0.8mm mild steel? Less heating needed for the thinner strip perhaps? One concern I have is keeping the brazing alloy away from the hinge pins. Is it just a matter of avoiding flux on those areas or do I need to look at so measures like toothpaste or permanent marker as mentioned elsewhere to mask them off? -R
Good afternoon, the steel thickness won't have much effect on the brazing process, either would work. 0.8mm will be stronger but more 'chunky' looking, you could always round the edges off a bit to reduce the effect. A bit of masking will do no harm, the braze is only really likely to flow on clean, fluxed surfaces... but the flux can sometimes run when heating, and of course it undergoes capillary action too, into places like hinges, the filler material then follows! So any precautions you can take are worthwhile, if only to remove stress and uncertainty!
I hope to have a chance to progress this at the weekend. Thinking a few steps ahead, there are a few pinholes in the case. Are these best tackled with a dot of alloy when I’m brazing the lid or should I be thinking of a ‘filler’ paint primer? The latter might be a bit more …sympathetic to overall condition and improve the overall finish, but I have zero experience at this point. -R
@IRM Sorry, I mised the question about masking for brazing, yes either of those would work, typist's correction fluid (Tippex) is another possibility, surely used more these days for alternative purposes than for typing?!? Others may have a different view, but I'd use more than just primer-filler paint for the case. If well cleaned up, you could fill the pin-holes with braze, but the more brazing you do on the thin sheet metal of the tin, the more you risk distorting it due to the heat involved. If the stove is going to be kept indoors, the pin holes should not really increase the chances of further corrosion. Sorry if there is egg-sucking instruction here, and please keep questions coming. 'Etch primer' is the best stuff to prime the bare steel for adhesion, but any half-decent primer or primer-filler would do. A proper clean first with naptha (Holts brake cleaner, panel wipe, Aspen 4T, Coleman fuel) will ensure a proper degrease. A product called 'paint stopper', Also called 'knifing putty', in single pack form in a tube, would be ideal here. It can be had from car body repair outlets, halfords, online etc but prices vary wildly. It is basically like thick toothpaste. Spray a coat of primer first, then trowl(/knife/old credit card) on a layer of paint stopper to fill the holes, level up the surface etc. Sand back, repeat if needs be. Then another layer of primer over the whole lot, followed by top coat. (If wet sanding, let things dry thoroughly before applying more layers of anything or the trapped moisture will mean corrosion! It's an ideal time of year for this, at least...) The advantages of paint stopper are that it can build up a pitted area far faster and more effectively than many layers of primer-filler paints. Unlike regular car body filler, it is far finer in texture, and has the same absorbancy as paints, so you do not get the inevitable visible line surrounding areas where body filler has been used which often shows through in the top coat. It needs no mixing. I'm sure there are a million ego-fueled youtube videos about how to be a proper manly man and use paint stopper like a Norse God! But it's as simple as described above. It's worth going to the effort in my view if you are going to repaint- I can't stand glossy new paint over a pitted, rusty surface. Better left alone, or made 'as good as new' to my personal tastes! Of course, the absolute ideal would be to use 2-Pack epoxy primer on the case, with a more traditional paint type over the top. The epoxy is far less water permeable than just about any other paint type, meaning the finish lasts a lot longer as corrosion is kept at bay. (Most paints are suprisingly permeable!). But epoxy is expensive, really needs rollering on with disposable rollers, and then lots of sanding to smooth down. It all depends on how much money, time, and effort you want to invest on 'shiny', especially if the object is subsequently going to get thrashed!.
Thanks @Blackdog, I will give the paint stopper a try. Shame I didn’t know about it a few months ago - I did up an old RM 320 with a stand that was very pitted. It came out looking painted and pitted… though I suspect it is not a given it would tolerate the modest temperature the stand can get to. -R
Missed this bit… I like to use my stoves, but I have a accumulated enough that it might only be once or twice a year. This is more an opportunity to learn new things (in time, skills) and hopefully be able to pass my stoves on in a useable state in the future. -R
Good stuff, as long as you enjoy the time put in it's not wasted! It's a bit of a double edged sword really, a thorough paint job with attention to detail will help preserve the stove, potentially for lots of use which is bound to affect the finish in other ways! The paint stopper will probably be about as heat resistant as most normal paints out there, think car bonnet temperatures in desert heats! Wet sanding, with fine wet and dry paper, is the way to go for a very good finish. No offence intended with my comments about rust pitting, it just always catches my eye (in a bad way) and I prefer to conceal them if attempting to make something look 'new' (or 'newer'!).
The saga continues… I cut two 0.8mm mild steel strips with holes / slits in one for a dummy run. Sanded, cleaned, masked, fluxed, clamped and ready to go: The hole in the middle simulates the rust hole in the case and I figured it would be a point at which to apply more filler to the centre of the join. I applied heat from the underside as shown above. I think the clamps were acting as heat sinks so removed the outer two before I managed to get any filler to melt. I used two fillers - Silverflo 38 for the tear on the right, below. Silverflo 55 for the other tear and the central hole to see how they performed - I wasn’t sure the high silver one would manage larger spacing. The results are below. Neither ‘tear’ was actually filled but the reinforcing strip was joined to the other strip. The ‘55’ end however did not form a join outwards to the end (above). That has me thinking ‘38’ is a better bet for the real job. I was unable to melt any filler on the central hole, despite getting the area red hot, it appears however that adding filler here was not necessary. Bad edge aside, would the join above have benefited from applying filler along the edges as well as from underneath? Should I have left the outer clamps in place? That might have reduced the gap the filler had to cross. Any other tips or suggestions? -R
@IRM Looks great for a first trial! Yes the 38 seems to be flowing better. Daft question I know, but are you sure you are getting things hot enough? I'm surprised the middle hole diddn't draw in any filler. Are the bricks vermiculite or insulating firebrick? It so, move them in as close as possible around the work to increase the temperature, as long as you still have good access. I think the issue with the side which didn't join is that the gap was too large for capillary action as you say, the clamp would have probably kept the gap tight enough. Maybe try again with all the clamps, as much heat as you dare, and draw in the firebricks if they are of the insulating type? Yes, a bit of filler rod along the edges will help, it's quite a large area to flood. Just keep everything as tight as possible. Good going!
