Well, that is for a good cause 
Iāll go through and see what my choices are if neccessary but I donāt know yet if it is needed, I am just interested.
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I have welded cast iron with 7018. Of course I weld everything with 7018. I think the most important thing is preheat and post heat with gradual reduction controlling expansion and contraction.
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hello johan, i have welded cast iron with stainless electrodes, works pretty fine, heating up was not needed, except heating up for cleaningā¦also our local mechanic has told meā¦
my hanomag tractor also has had cooling water in the motor oil, when i bought, it was a fraud, the owner know it, but i have had no intention of motorsā¦
but i was at least able to repair itā¦the tractor has separate cylinder bore, and there the water filters in the oil, a motorhead and also construction problemā¦the most water but goes in the cylinder when the piston was sucking, and than out by the exhaust pipeā¦very dangerousā¦
i tried new gaskets, they are thinner as the original, and also double gasket, keeps exact always for 5oo km, than sucks water againā¦
the motorhead was planed, but the problem comes from a construction fault ā¦the bore has a 1mm higher edge inside to protect the gasket, and where the prechamber comes in, this edge is interruptedā¦here the high pressure with long time wears out the metal, the gasket here was less pressed, and so with a while water entersā¦normally the motorblock must be planed, but this would say to make the half traktor in piecesā¦so i tried , where always the gasket burns out caused by less pressure on it, giving little fine copper pieces, shaped how the burned parts, under the gasket, this keeps up now for 30 yearsā¦also the gasket i have made by myself from thicker material, called klingeritā¦
when the motor runs, and i have seen bublles in the cooler water, i have seen that motor compression goes in the water.
the oil lids become a gray stuff on - water in the oilā¦in my case water that travels down between piston and cylinderā¦
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I tried welding cast iron with stainless electrodes a few years ago with poor results, I just needed a bracket on an old axle housing that I use standing on end with a blacksmithās vice on it. I use it for angle grinder work outside to not have sparks everywhere inside.
Of course I didnāt clean much or preheat at all and the cast iron seemed very coarse but I had to get a cast iron electrode to get it to stick, which was the only thing needed, no beauty prizes there, thatās for sure 
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Often times attempts tried, not worked; or worked barely, poorly; helps to define the needs for next time.
Think about the cake-like structure of cast irons. Versus the overlapping plates, OSB type structures of rolled formed and wrought formed metals.
Heating to near melting, or to actual melting destroys these internal structures. That melt cooled has stress to the near original structures in and of itself. Then fixing a true melted bead of metal added to this changed metals. Eeeek!
Way to many differentials once all cooled in hardnesses; underlaying grains; with then built in stresses; in-ability to then absorb and transfer working stresses. (Give you a whole new respect for old time riveting!)
So . . . all techniques are to minimize changes to the original metals peices. Have the minimal metals transitions edges zones left behind. āNormalizingā out to minimal any left behind internal stresses.
Normalizing out stresses is part of what the grinding steps or the pointy hammering tap, tap, tapping does. Welder men just like to weld. Think blacksmithing.
Sure I like dissimilar metals lower temperature brazing.
For your added bracket JohanM. to do that brazed you would have had to make up holding fixtures. Takes two hands to braze. Takes two hands to TIG.
Stick welding. MIG welding only one hand for the welding possible. The other can position hold one piece. If you are really, really good.
Ha! I aināt that good.
And these to work must melt the surfaces of the parents metals. Then back to those whole sets of changes made have to compensate for.
A lot like Life itself. Easy, quick now; exacts prices later.
Over set-up, and pre-prepped, and then the actual act is ho-hum a bit easy-boring. No drama. No fuss.
The judgement is the lasting results.
Regards
Steve Unruh
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Pre-prepping and properly set up things take time but in the long run it is usually faster in total since no re-doing is needed. Half-assed quick-fixing things has a place when in need but not for most things, they should be done properly if they are to last.
I donāt recall that I have brazed anything other than the copper pipings in my house and I am not even sure that is called brazing, more like hard soldering for a direct translation.
Yes, Not really knowing what I talk about, I imagine there would be cracks coming back where the two materials meet after welding, even with the āproperā stick/mig/tig but it must be pretty easy to overheat the material when brazing too. It takes experience and with that comes doing it wrong several/many times.
Working with cast iron I do understand why the hot riveting or even cold riveting was used widely. I have done cold riveting a few times but not needed, more for fun and esthetic reasons.
The tapping to get rid of stress in the material, I am guessing it also counteracts the shrinking of the weld when hammering with a pointy hammer to expand the metal slightly (blacksmithing) to relieve the strain on the parent metals and that is why only to do welds short and then tap tap tap. All to avoid cracking next to the weld because the weld itself does not crack.
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Yes, when welding cast-iron itās always good to āpeenā the weld, with a pointy hammer or a needle scaler, specially recomended when ācold-weldingā cast-iron.
Drilling and put small pieces (pinās) of good weldable steel, in a zig-zag pattern on both sides of the crack, and āweld them inā does wonders in reinforcement of the weld.
And: im going to check up some stainless rodās iāve used on cast-iron, green coating, just stainless, not acid proof, gives a softer, more āfloatingā weld.
And for brazing cast-iron, those brass, gold color rods work great, with old-time, prohibited, flux (marked with a skull)
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That sounds like a good idea, never heard that before.
I read on a brazing rod pack that brazing rods with phosphorous in them is no good for steel brazing, will look for some brass rods.
I have half a pack with stainless electrodes that are green, they are not esab, i wonder if they are Avesta but I am not sure, the combination P7 comes to mind though. Old flux containers with skulls is in one of the welding lockers 
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Avesta/Sheffield, im pretty sure itās the same brand i have, i recognize the labels p3, p4, p5 and more, i got them from my grandfather that worked at SkƤrblacka paper mill, he got them there so they are pretty old.
For brazing the non- flux coated yellowish/gold brass rods are often low in phosphor, the older ones, the phosphorous/ copper-phosphorous are slightly darker, more copper colored. But i can be wrong 
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Iāll take a quick look at the brazing rods tomorrow 
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These are the ones I found, mostly iron rods, some phosphorous-copper rods, some brass rods in the bundle too, silver-phosphorous-cooper rods for drinking water (those I bought, not in pic) and then the castolin ones which perhaps is something, it says it could be used for cast iron too.
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I just thought Iād post a link to the MATWEB site. I think itās very helpfull. I searched [cast iron weld], and got some good information.
Rindert
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Some Sunday fun,ā¦. 
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Lately, the start-up of the gasifier has been taking a little longer than usual, but I decided to do a thorough cleaning, well, there are a few pieces of āstonesā underneath, and the restrictor tube is a little damaged. I did the last emptying of the gasifier 100 hours ago, when I changed the restrictor tube.
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Stones = slag? Too much air? Something happened to the cetral nozzle?
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I dont dare to say anything. Only that I am impressed how airtight your build is. Any leak would apear when you start up. And I am trying to understand how all is connected.
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JO, the central nozzle is undamaged, for the formation of slag, a very high temperature and density of ash is required in the hot part, which does not retreat into the ash space, in which the ash level is too high,ā¦ , to conclude, the fault was negligent and a lazy operator who didnāt remove the ashes, ME 
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tone, the little burnt away piece of metalā¦maybee this depends on the gas exit out of the gasifier in the double mantle, if only one exit of some more around the gasifier, the gas travels the shortest way and so not a even heat distributionā¦? or the slags have created a ostacle, gas concentrates too near to the metall, overheatingā¦like as in charcoal gasifiers can happenā¦?
perfect work, not much maintenance neededā¦
ciao giorgio
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There in the āVolvoā thread, I said something about reworking the gasifier or the hot zone, well, letās not just talk about it,ā¦
comparison old and new unfinished unit
old and new nozzle, in the middle the nozzle for the upper part
larger diameter of the restriction pipe
nozzles installed in a diameter of 14" for gasification of fuel against the walls and a tube for reflection of hot radiation around the upright grille are also missing
of course I will save the old unit as a good spare part if the attempt fails
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Thanks Tone. That reflection pipe is getting real hot. Doesnt it meld?
The Tone nozle is made of some very hard material if I remember correct. Did you drill holes in it?
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