Jump to content
I Forge Iron

Beginner Attempting Forge Build


Recommended Posts

Alright folks, I have done a ton of reading on building forges. I am doing some of the technical, material steps however, for simplicity's sake, so please don't be too hard on me. 

I chose to build a rectangular forge, again for simplicity's sake, as well as cost. I am using fire bricks, cemented together. I will have a metal frame built around it, with a small air pocket that will allow me to add kao-wool later if I desire. The pictures below show the progress this far. I am planning to add one more row of bricks to the front. That is where I plan on having the burner entering. That leads me to my question. 

I am part way into the build, and looking for some advice on burner placement (I know, another can of worms containing everyone's opinions). I am using a version of a venturi burner I mostly copied from the common videos on YouTube. My thought is that I will Mount it at the front of the forge, pointing towards the rear on roughly a 20 or 30 degree angle to help disperse the heat more evenly that a straight vertical burner. 

What do you guys think of the angled burner idea? 

Thanks in advance. I am excited to hear what you're guys think





Link to comment
Share on other sites

No insult intended, but you have either not read most of what has been posted on this site regarding gas forge design or chosen to ignore it.  Your gas forge design has so many potential issues that I can't list them all.  Here are a couple of problems I see:

  1. Too much internal volume for efficient forging.  If those are standard brick sizes, I see around 1,300 cubic inches now and you are looking to add another course of bricks.  A good internal volume for a starter gas forge is around 300-400 cubic inches.  As it stands I'd expect this forge to require three or four 3/4" NA propane burners. 
  2. There are a lot of videos on you tube regarding burner design, some better than others.  Hopefully you are following one of the better ones.
  3. Little to no insulation value from the hard fire bricks you have used for the inner skin.  Not a terrible idea for a production shop inner liner, but pretty awful for a hobby smith.  Even if you line around it with the 2" thickness of high temperature blanket you will have a massive heat sink which will either demand a ton of gas to get up to temperature, or really good doors, outer insulation and a lot of time.
  4. The mortar you are using is good for sealing seams between brick, but is hardly structural.  The thermal expansion the forge will experience will more likely than not break the joint, and then there is nothing holding your roof up.  I would at least rotate the forge 90 degrees about it's axis, and even better make the outer metal frame compress the bricks into place.  In any case you need to prepare for the bricks to crack during extended cycling (which they will in my experience).  Of course if you make the compression frame around the hard brick, you won't be able to insulate outside that.
  5. As noted, you will likely need several burners, so the one burner angled towards the back of the forge doesn't really bear analysis.  There have been numerous posts on this site regarding different options for burner entry and angle.  Hopefully you will look at those before finalizing your forge.

Personally I would put this one aside and start over.  I understand the cost issue, but this is another case of skimping on first cost which will result in paying through the nose thereafter.  The fuel costs for running this forge are likely to be outrageous, and a better design will pay back pretty quickly.  Honestly I rarely advise going with one of the cheap e-bay forges, but in this case you would be better off getting one of those, with a burner, and just coating the blanket properly.

Feel free to prove me wrong though.  I'd love to see you be successful with this forge, would make things a lot simpler for others.  At least you didn't build it out of concrete blocks or a homemade plaster based refractory.

Link to comment
Share on other sites

Ok. Thanks for the input guys. I think what I will do is heed a portion of your input, cut the size of the forge in half, then plan to build a round forge in the future when these bricks crack. 

I will take the bricks standing upright and lay them flat. 

The metal frame will hold the bricks tight and allow for 1" of kao-wool 

I am using a 0-30psi regulator so hopefully this will get things hot enough for me to get started smashing some steel


Link to comment
Share on other sites

You could line the inside of the bricks with Kaowool, but I have to ask what's the point?  The bricks are far heavier than sheet metal and if the wool is on the inside there's no benefit of the flux resistance of the bricks, so you have made a heavy, brittle framework for your forge at that point.  None of us like to spend money on a project and then toss it aside, but if you're heading in the wrong direction sometimes it's better to start over than to push forward with a plan that will cost you more in the long run.  You can still use those bricks (with an IR reflective coating of something like Metrikote) as consumable flooring and/or doors for your forge. They don't have to go to waste.  If you have access to ceramic fiber blanket and a small tank, stove pipe, or sheet metal my opinion is you'll save yourself trouble and money by changing your design now.

Link to comment
Share on other sites

Welcome aboard Mil81, glad to have you. 

Your's is a perfect example of why I tell new guys to ignore Youtube and other online how to videos, a large percentage are by guys who have no idea what they're doing but managed to get something to work. Too many are only bad designs but some are outright dangerous. Once a guy has some experience you can learn a lot, especially from the failure designs that have been MADE to work. Okay, enough of my Youtube rantings. 

I hate to say it but my recommendation is you put those very handy bricks on a shelf under the bench. There is always use for fire brick, even splits. Those ARE fire brick yes? I'm afraid making what you have an effective and economical forge would cost more than starting over. Too often the cheap comes out expensive.

The "Forges 101" thread here on IFI has plenty of good designs and links to good ones. I'm not a huge fan of propane or freon tank forges but there are good plans for one on Wayne Coe's site and lots of guys have built them so you'll have plenty of examples to help winkle out the fiddly bits.

We're not picking on you, we don't want to see you invest a lot of time and money in a piece of equipment that won't do what you need or want. We'd really prefer to get you started with good tools so you'll post pics of beautiful forgings. We LOVE pics and even more we LOVE helping folks get good SAFELY at the craft.

Frosty The Lucky.

Link to comment
Share on other sites

Man, your name process true!!! Lol. 

You are 100% right. I guess I was grasping at straws. 

Idon't know if I have access to ceramic blanket outside of Amazon or eBay, but I will figure something out. 

Fair enough. I concede. I may have access to a 30lb propane tank that I could repurpose. Then it's just a matter of finding some ceramic blanket that won't take a year or a fortune to ship up here to the great White north

Link to comment
Share on other sites

There is such a thing as K28 insulating firebricks; they are highly insulating, will help solve the mechanical problems with your outside bricks, so light that shipping is cheap, (as is the price of the bricks), and good for 500 higher degrees than Kaowool. BUT they have a very open cell structure, so you will want to give the inside of the forge a refractory seal coat from Wayne. You can buy the bricks on eBay.

Link to comment
Share on other sites

I live in a rural area, so shops that sell the things I needed to build my forge were not local.  I tried to find an online source that had it all at the best price, but could not find that source.  I got my rigidizer and Satinite from one source, my ceramic wool from another. I got the 1 inch 8 pound 2600 blanket from an ebay source that offered free shipping.  I got all of it in very reasonable time.  I got my Plistix from Wayne here on the forum.   I built the burner before I started putting my forge together and checked in with the resident experts as I went along.  My forge has been on line for a few months now and it works great.  I stand on the shoulders of giants. 

Oh, If you care to see my progress, it is in my another newby thread

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...