My gas Forge

[SharpPotato]

I know a lot of threads here are people asking questions already answered, so I will try and keep this simple.

I have a bunch of brand new firebricks I used to rebuild my fireplace last year. I have half and full bricks, about 15 of each. I have multiple propane tanks that are full, and lots of thick metal on hand. The bricks I was told are high enough quality to build a kiln. I also have Heat Stop 50 refractory mortar. The brick yard I bought them from said they are high enough quality for any application where they will be exposed directly to very high heat for long periods of time. They were the best firebricks they had.

 

So the questions I have are pretty simple. I want to make a small brick forge that runs on propane so I don't need to put a chimney in my shop, and line the inside with 1/2 bricks so as they get damaged I can slide new ones in. Should I get a different type of half brick to line the inside? I dont want to spend more than required right now.

 

Also, I've been looking at burners. They arent cheap, so I dont want to buy the wrong one. I just want something where I should be good for a few months before I decide if I want to change anything. I read using full brick for the floor will suck the heat out and stop me from getting it super hot. I will spend $100 on a burner now if it means I can use it for my next forge too. I dont want to spend more than needed tough.

 

Just my background. Ive been welding for almost 10 years. I make railings from time to time, and got an anvil to raise my hot work skills to the level they need to be for a guy who live in a historical city. I have used an ASO and oxy/acetylene torches in the past. I just need a forge to heat right now about the last foot of rail at a time. I dont want to burn more fuel than needed, so I would like a single burner to start, and if that is not enough, I figured I could make the forge longer and add another burner.

 

I know this forge in the video probably isnt the best, but I thought the design may benefit me. I was thinking maybe I would make one of these long enough for 2 or 3 burners, but only put in one to start. I figured I would save fuel and figure out how long I actually need it that way. I have made the mistake of using my materials in the past, only to realize when its too late I should have done  something a better way. Since I will be tying up at least a couple hundred bucks, I hope whatever I do keeps me happy for a year. The burner on this design made me skeptical it would be worth the time for me to make. I dont know enough though.

 

 

[Buzzkill]

Yes, there are lots of threads on here where people have asked pretty much the same questions you asked.  The Forges 101 topic will answer almost any question you can think to ask regarding forge construction, but it is lengthy.

I'll hit a few points here for you though.

Some of the bricks used to build or repair fireplaces can handle the heat, but they are not well suited to forges or kilns because they are not very insulating.  They are cheap to buy but will cost a lot more in the long run due to the extra fuel required in operation.

You won't need a chimney in your shop with a propane forge, but you will most definitely need good ventilation.  Others on here know more about the volume of air per minute that should be part of the plan.  You'll also want carbon monoxide and carbon dioxide detectors to let you know if the levels are becoming unsafe for you.

Based on the background information you gave, you should have the tools and skills to build your own burner inexpensively.  Here's the link to a burner design that to my knowledge is the simplest effective design around:

https://www.iforgeiron.com/topic/43976-t-burner-illustrated-directions/

In the video you provided, I believe the guy is using insulating fire brick, which is much better for a small forge than the firebrick you have.  There's nothing wrong with a small box style forge, but his burner is marginal at best and the distance between the ceiling and the floor make it unlikely that full combustion occurs before the flame impinges on the stock.  That's not a desirable feature.

So, if you want to do it once and have an effective, efficient, low cost forge and burner, my strong recommendation is to take the time to read through at least Forges 101 and Burners 101 on here and maybe a few others that catch your eye.  It will take a few hours of reading but it can save you a lot of time and money in the long run.  Only you can decide if the time invested is worth the amount of headaches and cash it will save you in the long run.

 

[Mikey98118]

Since he would need to learn that same knowledge even to make an informed purchase, it is certainly worth a few hours.

[Irondragon Forge ClayWorks]

Have you read this yet?https://www.iforgeiron.com/topic/53873-read-this-first/

 

[SharpPotato]

13 minutes ago, Irondragon Forge & Clay said:

Have you read this yet?https://www.iforgeiron.com/topic/53873-read-this-first/

 

Yup, I read a lot of that thread. Its been so much info on here.What I really would like are the formulas for calculating everything volume to burner/btu ratio. I have thought about casting a forge too. I have a lot of fireclay, lime, portland cement. If anyone has a good recipe that would be good too. I dont think the ones I know will hold up to a forge. I could cast it with a bung of some type to stick the burner in. I am not sure how much volume to how many BTUs. I want it to get as hot as possible, while being as efficient as is reasonable to have a good burning forge. I already have a large exhaust fan in the roof of my shop, it like 36" 1/3hp. I have carbon monoxide detectors too.

[Buzzkill]

This thread has some of that info you are looking for in it:

https://www.iforgeiron.com/topic/44773-burner-to-cubic-inch-relationship/

DIY refractory mixes for forges are a waste of time IMHO.  Been there, done that, came up with something that held up to the heat ok, but wasn't very insulating and was very heavy. Looking back at the combined time and money I spent on the mix I would have been better off purchasing the right materials to begin with.

Wayne Coe is a member here and he sells small quantities of castable refractory and other forge building supplies at reasonable prices.