Another propane forge build

[Charlie Lewis]

I have been wanting to make a smaller lighter weight forge, and I have also wanted to mess with castable refactory. This little forge is kind of a proof of concept and experiment for me.

The chamber is made from castable refractory (mizzou) it is about a 1/2" wall thickness. I used two pieces of pvc pipe to make the mold. The chamber was then wrapped in ceramic wool and shoved in the can. I used a bit more cement to seal up the ends of the ceramic wool.

The burner is length of 3/4" black pipe with a mig tip pointed at it.

The burner is pretty big for the size chamber, it gets hot.

 

[Bruno]

Where did you get the castable refractory?
I am still trying to figure out what a good choice would be.

 

[Charlie Lewis]

I bought a bag of from these people,

http://thinkhwi.com/locations/

They have a distribution center in Dallas, I happened to be driving through so I stopped in to see if they would sell a single bag. I do not know if they have European distributors.

 

[Bruno]

They have a distribution center in the UK, it seems.

So Do I understand correctly that this is basically an inner 'tube' of cast refractory, surrounded by ceramic wool?

 

[Charlie Lewis]

Yes that is right I cast a tube then wrapped it wool. Here are some pics of mold. I forgot to take picture of tube/chamber.

I do not really think this is most practical way of doing this, but I wanted to try it out.

I think a fire brick floor with rounded walls and ceiling made of ceramic wool might be the way to go. I think any number of ways would work.

 

[Victor Creazzi]

So , you were able to pull the pipes out after the mix partially set?
Or did you let it fully set?

 

[Charlie Lewis]

It was pretty fully set, about 4 days. The burner hole came out easy after twisting with pipe wrench, the main core one took a bit of tapping, but it was not a big deal. Just pvc, no mold release of any kind.

 

[sbogill]

It was pretty fully set, about 4 days. The burner hole came out easy after twisting with pipe wrench, the main core one took a bit of tapping, but it was not a big deal. Just pvc, no mold release of any kind.

You could have just heated the pipe with a heat gun and pulled it out really easy. PVC turns into a wet noodle with some heat.

 

[Victor Creazzi]

Glad to see that you found a use for the anvil cap.

 

[Charlie Lewis]

Glad to see that you found a use for the anvil cap.

It has come in handy, it lives on that anvil, I like it.

I made a little tripod for the forge.

 

[Bruno]

It was pretty fully set, about 4 days. The burner hole came out easy after twisting with pipe wrench, the main core one took a bit of tapping, but it was not a big deal. Just pvc, no mold release of any kind.

Bit of a necropost here, but I wanted to respond. Last week I cast refractory cement for the first time. Before, I used fireclay.
I did what charlie did here, with fireclay and the results were bad. It shrunk pretty bad and tore itself apart. That is why I cast 2 halves this time.

Upon working with the good refractory cement however: a) it doesn't shrink, and b) it releases very well and c) refractory cement is still cement. Unlike fireclay, when it sets, it is rock hard. So for my next forge, I am going to give this a try. Currently I am building a bigger one that is needed for forgewelding larger billets and ingots. But when that is up and running, I will probably add a smaller one for forging bar to blade. Additionally, I would keep it free from Borax so that the blades will be cleaner after forging.