Barrel Furnace build

[jordhandson]

Ive had the afternoon off today so here it is.

First thing I sourced was a beer barrel the one I got was a stainless steel one I don’t know if it makes any different whether you have an ally one or not but heat wise glad I had stainless. Plus it made the build better for welding.



I cut off the top and turn the top over this became the lid.

I cut a hole in the base of the barrel this was to become the drain should I have any molten metal spills.

I also at this time cut the hole in the side for the burner, I new I was using a 65mm tube burner so the hole was cut to suit here you will need to cut what ever size burner tube you’re going to use.

Regarding the height of hole and angle I was aiming for 100mm thickness off the bottom and aiming to have 100mm thick sides so you will need to allow for this when cutting the burner hole. Depending how thick your having your furnace walls, ie the thicker it is the more heat your furnace will hold and how quickly it gets up to temp and how fast it cools. On the down side the thicker your mortar and insulation is, the smaller the melting pot or crucible you will be able to use, these factors will need thinking about before you build.

I then added some steel bar reinforcing bars in the lid I had some off cuts of stainless about so that was used I suppose you could also use standard reinforcing bar or just plain round steel bar.



Inside the barrel still using the off cuts added some reinforcing bars to the bottom and some smaller bars up the side to give the mortar something to bind to I don’t really know if this is really necessary but I am an over builder lol




At this point I started to make up some sort of trolley as I figured it was going to rather heavy with all the cement and luckily I decided that I wanted a way of moving the lid about rather than lifting it on and off. I made a foot pedal so when you push it down it lifts the lid only about an inch or so, the lid can then be swung left or right.



This is what I did but you can build your trolley anyway you like. Oh one thing make sure you get some good strong castors if following my route. This way does work well though, and believe me you do not want to be thinking you’re going to be lifting the lid on and off, the heat and weight is immense.

 

[jordhandson]

The lid, and base and side were then laid with 25mm thermal insulating blanket




Then I made up a plug like shutter, ply top and bottom with some ally bent round the ply size of plug will depend on how thick you walls are and how big or small your melting pot or crucible is going to be.



Crucible size and space

A good general rule is 2.5" to 3" of clearance between the crucible and furnace wall and 3" below and above the crucible to achieve good combustion if you are going to melt cast iron or bronze , you can get away with allot less clearance for aluminum.

At this point I also found a piece of old plastic waste pipe for the drain hole shutter



Next step have your kit ready for doing your mortar It was chucking down outside so I did all my mixing in the wheel barrow, I also made a vibrating type poker on the end of my cordless for getting the mortar compacted down in the side I think it was a great help



Here I used just add water refractory cement if anyone needs I could dig out where I bought it from or just google refractory cement there are a number of places to get it from I had no preference just the best price.



I mixed enough just to do the lid and the base of the barrel not the sides yet. I did the sides a couple days later once the base had cured a bit made it a lot more controllable.

 

[jordhandson]

I did the base same as doing the top and bottom making sure I got the refractory mortar rammed right down in there between the plug and the wall so as not to have any trapped air pockets which will expand with heat. Sorry I forgot to take a photo before I took out the plug. I also had some mixed mortar left over I put into a paint mixing pot and it made a perfect top hole plug which is handy if I want to hold in the heat after the flame is off.


Notice here is where I left the mortar approx 1/2inch shy of the top because once the mortar was hard I added a coating of the stove cement for a bit more heat protection probably not needed but that’s me, on the plus side I do think the furnace will last longer under firing.
I left it in this state for a week to let it cure under its own time about a week later I put a light 60watt light bulb inside with the lid on and left it one for another week to draw out as much moisture out as possible before putting any real heat into it there’s lot of conflicting info on the net as to firing these furnaces some do it quicker than me but heho it up to you how long you leave it. With work and stuff mine sat for at least 2 weeks before firing. I then brought the heat on real slow say a couple hours on 100c

then left it overnight next day a couple hours at almost 300c

then finally the next day a couple hours at 650c ish that's a John Deere piston liner pot in there

I didn’t take it any higher as it was the temperature I was aiming for to melt ally, I have since had it up to 850c before the nerves got to me.lol

I had most of the stuff needed kicking about and the only things I had to buy was

3x 25KG 1400°C Castable Refractory £91.50

1 x 25mm Ceramic Fibre Blanket £46

1 x Everbuild KOS Brick Fire Furnace Stove Cement Buff Heat Resistant - 25KG

£25

 

[jordhandson]

Once you get the furnace built you will then want to get some safety kit together some good strong boots, gloves, face shield, I actually pickup a furnace suit dirt cheap off the fleebay, start making some tools a steel melting pot and eventually buying a proper crucible.





I did between doing the furnace and other thing I start testing and making the burner but that’s going to be a separate posting.


One thing I have to say though if you go down this route it will be at your own risk these things can do you serious harm if you don’t have safety gear and a safety plan and I take no responsibility.

YOU DO IT AT YOUR OWN PERIL STAY SAFE

Cheers

Jord

 

[Screwdriver]

Excellent posts thanks. This is very nearly next in my list!

I still have a respectable pile of very similar cylindrical objects <name withheld> so I can make up a matching set to go alongside the beer barrel forge

Thread deleted sadly....

 

[jordhandson]

Nice forge Screwdriver my brother wants me to make him on along the lines as yours shame about the missing thread would have been handy, do you recon it along the same principles and the furnace build

 

[Screwdriver]

Very similar. Let me see if I kept a copy...

I still have all the build photos and there should be a burner build thread on here too. I’ll dig up the links.

 

[Screwdriver]

Plenty more info here: https://www.mig-welding.co.uk/forum/threads/ye-olde-forge.77451/page-11

You might want to skip past the first few pages (personally, I actually do enjoy re-reading my old posts )

 

[jordhandson]

Plenty more info here: https://www.mig-welding.co.uk/forum/threads/ye-olde-forge.77451/page-11

You might want to skip past the first few pages (personally, I actually do enjoy re-reading my old posts )

Yeh I know what you mean It was a real pleasure today with the old photo's looking back on things youve made lifes so fast

 

[jordhandson]

Yeh I know what you mean It was a real pleasure today with the old photo's looking back on things youve made lifes so fast

Plenty more info here: https://www.mig-welding.co.uk/forum/threads/ye-olde-forge.77451/page-11

You might want to skip past the first few pages (personally, I actually do enjoy re-reading my old posts )

Fantastic post I have been looking at the same post for ages as I am going to build your anvil stand keep it up some great idea there supercheers

 

[Screwdriver]

Should be self explanatory:

I used 2" layers of kaowool, a few lightweight refractory bricks for the base and plastered the inside with refractory cement. The front door hinges to allow access for repacking and there's a hole at the back for swords (!). I just block up the holes with odd chunks of firebrick coated in refractory for durability.

I could upload the lot again if the coast is clear...

 

[jordhandson]

Should be self explanatory:

I used 2" layers of kaowool, a few lightweight refractory bricks for the base and plastered the inside with refractory cement. The front door hinges to allow access for repacking and there's a hole at the back for swords (!). I just block up the holes with odd chunks of firebrick coated in refractory for durability.

I could upload the lot again if the coast is clear...

Cheers another project on the back burner lo Thanks

 

[Tom O]

Nice build When I built mine I just used 2 wraps of the fiberwool that was then coated with a Zircon mixture to increase the heat limits. I like the fiberwool because you don’t have to worry about moisture in the refractory and it heats up faster too I run mine on propane with a fan feeding the blast tube. What are you going to use for sand I use masonary sand as it’s finer and leaves a better finish.

 

[jordhandson]

What are you going to use for sand I use masonary sand as it’s finer and leaves a better finish.[/QUOTE]

Sand do you mean for casting???

 

[Tom O]

Yes I was just wondering if you will use the ready mixed sand for casting or use conventional sand with bentonite, I found masonary sand is quite fine and leaves a good finish.

 

[bourbon]

https://mindsetsonline.co.uk/shop/petrobond-sand/