Making a Foundry Furnace From An Old Water Heater, Part 1

welcome to farm craft we are gonna build this foundry furnace starting with the shell of a water heater that I tore down in a previous video first I fold the seam back together essentially reversing what I did when I took it apart a lot of the ideas that I'm doing to make this furnace have come from another youtuber that I watch and actually correspond with some named lucky Jen 101 or 1001 this guy is a master of a foundry work he does cast-iron like it's nothing and and he's got lots of videos on how he does things and how to make a furnace how to make a burner and the guy the guy just knows what he's doing so if you want to learn a lot go over check his channel out tons of information over there that has helped me so much that's a pretty heavy skateboard alright let's get back to work piece of quarter-inch plate here I'm gonna mount this on top of that in the bottom for my crucible to sit on to inch-and-a-quarter fire bricks they're gonna be right in the middle around it I'm gonna put insulation to fill that area then we're gonna end up covering that with say tonight the burner is gonna come in right here but this is obviously pretty flimsy and I'm going to be cutting a hole through there at the right height I'll have it so that it ends up just about an inch above the finished surface what I'm gonna do is I'm gonna make a bracket that's going to be both inside and outside that this can slide into I'll actually have a tab here so I can bolt it in place so this will be held rigidly but it'll also be removable [Music] I'm gonna have four inches of insulation in here just a little bit more than that will be the inner wall I need the burner to come through basically pretty close to that so that it shoots in here and then makes a swirl this is gonna need to sit in there like this obviously I can't have this support bracket here right in the middle of the of the flame so what I'm gonna do is this one welded on here and then this one is going to be hidden inside the insulation so something like that figuring out where I want this internal brace to be got it marked with some marker now this top part is a little flimsy I've got this piece of stainless steel that I had laying around I've just bent it by hand now most people I think would tell you you can't weld stainless steel with just a regular MIG welder set up but I've done it before and it worked okay [Music] now obviously the weld is not stainless I wouldn't use this on something that was critical that if it broke it would be the end of the world but since the work falling on this looks like a weld to me obviously the water heater shell is only a small part of this build but it it gives you a starting point and really kind of helps you get going it's not an easy thing to make to make a large cylinder like that so it's nice to have something for free that's just the right size this will give you a little perspective here's my old furnace isn't that cute I can actually adjust the picture this burner slightly by moving this outside bracket I can now weld this other piece on I'm just going to tack it in a couple places that way if I ever need to move it it's not a big deal all right I'm gonna make the lid this is a three sixteenths plate [Music] so if you put it at an angle so I'm on the belt here and I'm on the other side there I can use the entire belt and also use the entire table like I don't wear on just one part of the belt now I need a 4-inch hole in the center here so I'm gonna set my compass here for two inches so why am i building a furnace with just insulation instead of just using refractory like so many people do well there's a couple reasons the refractory is very expensive much more expensive than the insulation and doesn't have as good of insulating properties and the other is it has less thermal mass this furnace is going to heat up much faster and allow me to melt metal faster all right there's my lid that'll work don't you think yeah me either no it needs a needs insulation of course I need to do something like what I did here metal on the top metal on the sides insulation in the middle got this piece of scrap left over from the roof that went on this building actually it's 30 thousandths thick steel it's pretty heavy stuff so what's a nibbler it's air powered and this little guy goes up and down it's more narrow on the upper section than the lower section there you can see it right there so the piece of metal is against the more narrow part and then when the wider part comes up it basically sheers it off it makes these so it's just nibbling away little tiny bits of the metal does a good job cutting so I cut out this piece of hardware cloth [Music] so I ordered 20 pounds of say tonight that is a refractory coating that's made for real high-temperature stuff like this it's kind of funny it's called say tonight is that a pun is that like like as hot as hell I don't know it's made of Chi night which is a mineral and then mullite which is processed Chi night and then also aluminum oxide and some other stuff so at this point it's just a fine gray powder feels like flour with just a little bit of grit in it water I have no idea how much I want it to be something I can brush on you want it about the consistency of sour cream that's about what that is I want this flat is because the lid needs to sit on it I'm going to do the same thing to the lid so that the two surfaces mate with each other and don't allow a bunch of leaks okay now this is just a mirror yeah I should have should have known that was gonna happen don't do that that is stupid if I could put some newspaper down go ahead and put the mirror on that take the mirror off and just let the newspaper dry there and then I can burn the newspaper off later I didn't have any newspaper handy so I'm just gonna use regular paper little gentle pressure down all right I'm gonna leave it like that to dry so I hope this paper wasn't a mistake totally making this up as I go came off pretty easy it's been probably two to three hours so this is actually a really good time to take it off it's just coming right off because it's wet I think if you were to let it sit and dry for a long time you'd have to go ahead and burn it off there's the lid also feeling very wet so I'm just going to let them dry here overnight so I'm gonna let those cool off and then I'm gonna come back and do it again and keep doing that until it's good and dry so here it is after being flamed twice it'll turn black and then when it actually cures it turns gray again now one thing that I that I was thinking this area in here is all gonna be easy to cure I can just fire the kiln this area right here which is not actually in the kiln the lids gonna be sitting on that out here is not going to get that hot so it's not gonna cure by firing the kiln I'm going to try and see if I can just use my weed torch and cure it that way I think what I'm gonna do is I'm just going to coat this with some standard refractory that doesn't require firing in order to cure it just here on the top so this is my fourth time burning this [Applause] so that's cured right there that section there must be thicker because it's still not I'm going to use the foundry burner to fire the inside that right there is an old vacuum cleaner that I'm using as a blower there's my propane tank and that's a 30 psi regulator [Music] they get long and is really hot in there so that certainly cured the say tonight inside so I'm gonna let that cool off now I just welded on tabs all the way around it five of them so that technically if I took the burner out I could actually pick it out obviously I'm not going to do that I just didn't want it to be wobbling around it's probably past time that I secured the burner so I just need to weld a tab on to here that I can then bolt that burner into place so now when I put it in there this bolt will be able to go screw into that so here I am cooled off and fully cured and you can actually see that inside it's a lighter gray than it is here that I did with the torch so I don't think that's actually fully cured around the edge so I'm not putting any more say tonight there where it's not going to be exposed to the inside of the furnace on the lid you've got the same thing in the center you can see where the furnace was on the outside you can see that it didn't didn't fully cure so change of plans I am going to put standard 3000 degree refractory and get this stuff on Amazon I'll put a link in the description dries really hard really really tough I'm gonna put it around here I made this disc to act as a guide that's what the inside of the furnace is and I'm gonna put a refractory all the way around and get it nice and flat there all the way around get it nice and flat and then once that set up then I can come on the inside with the second coat of say tonight right press that down a little bit I want all the high spots to go down squeeze into the low spots it doesn't have to be level it just has to be flat and it's not the end of the world if a little bit leaks out of the sides but it's just gonna be a lot more pleasant to use if it's not doing that the question is do I leave it like that or do I try to peel that paper up I'm not sure what it'll do comes off very easy I'm gonna let it set up like that see in a couple days all right this is what we look like after the first layer of non curing refractory I'm gonna do one more layer on both of them get that nice and flat the mortars not fully cured but it's dry enough I can set the lid on and start on the edge [Music]

Channel: FarmCraft101

Views: 87,903

Rating: 4.9354367 out of 5

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Id: 1YO7ymbbNLQ

Length: 16min 26sec (986 seconds)

Published: Fri Mar 08 2019