Hello Hello

I am not a smith, I'm new to all this so bear with me, however I’m helping a friend build their first home forge. We want to make something that’ll last at least into his intermediate smithing journey. 

After digesting some of the info on here I understand a round forge is the way to go, or if not round, a square forge with a ribbon burner. I’ve unfortunately had a tough time finding a used air compressor or steel pipe large (and cheap) enough for a round forge. I will continue searching in the coming weeks and swap to a round forge build if the opportunity presents itself.

The current plan is to make a double burner (venturi or T) square forge out of firebricks (with a welded frame and stand), and once the time comes for an upgrade we could potentially swap the same forge to a ribbon burner design down the road. Which brings me to some questions:

1. Are vortex currents still a consideration for torch placement in a square forge? Is there an optimal position for the torch? I’ve uploaded some images of potential options, any thoughts appreciated. 

2. I see hard alumina firebricks are great for their durability but work against use in fuel efficiency and insulation, and so are recommended to be used for the floor of the forge only. How bad of an idea is it to line the sides of the forge with hard bricks as well? (hard bricks on sides are 1.5inch thick) How much would that spike the fuel usage? Reasons for doing so would mean I can avoid cutting soft bricks, the dimensions of the hard bricks on offer work out nicely for the size forge shown in images, about 5 inch by 6 inch fire chamber, plus they're cheaper.) We could just cut bricks if it's worth it though, or just make a smaller forge. 

3. And I can't help but throw in a final question, even though it's been asked and asked. How much worse is a square forge? Am I barking up the wrong tree and should force a round forge build. If I find no round steel housing, I’m half a mind to try casting a round chamber inside a square firebrick shell as shown in images. Is the benefit of a round forge worth the extra work? (plus, to check my understanding, do I have the torch placement correct for a round forge)

Props to this whole forum community, appreciate all the info on here (and any help with this), cheers

Welcome aboard Hotrock, glad to have you. If you put your general location in the header you'll have a much better chance of meeting up with members living within visiting distance.

Have you actually read the Forges 101 section of Iforge? Your drawings indicate you're just guessing. That isn't a dis, everybody speculates as they break into a new craft, we all do it. It's us old timers job to tell you when you're wrong and explain why.

So, I strongly suggest you read the Forges 101 section here and you'll see some proper applications of your concepts. 

A vault or mailbox shape provides the better of both worlds, round forge and square. My two main propane forges are rectangular, one the older is impractical on a number of fronts but I was starting to get the idea. My most recent NARB forge doesn't get as hot but for general smithing and heat treating works a treat.

I've pretty much laid down my hammer so never made my next forge which would have I HOPE been better than the previous ones.

Our club had a two day burner and forge build clinic and we came up with a small bolt together Morgan-k26 light alumina firebrick forge in a bolt together frame driven by a single 1/2" T burner. It works very well will go from room temp to high yellow in under 5 minutes and just sips propane. Still you need enough basic knowledge on the subject to ask meaningful questions and understand the answers or anybody trying to help you will spend most of their time explaining basic terms, materials, general whys, wheres and what fors. of the things.

Frosty The Lucky.

Thanks Frosty, may of jumped the gun, I'll get back to reading 

It's alright, it's normal and I'll be more than happy to help once you have a better idea of what's what. 

I dropped the ball in my last reply I should've included the link to the section. https://www.iforgeiron.com/forum/65-gas-forges/

You don't need to read the whole thing, filter through subsection titles and skim threads till you get to ones that interest you. Most titles and subjects will give you a good idea of what we were babbling about.

Frosty The Lucky.

An "intermediate" forge simply does not need the very best burner in the very best forge shape or design. A square brick-pile forge with a burner or burners placed high up on one side, shooting flame across to the interior's far side, a little below its ceiling is an excellent, efficient, and serviceable design for minimal effort. Save fancy forge plans for the future, and build something proper for today's needs today.

This advice is being given to you by the most notorious picky-butt on IFI, so maybe you should listen up.

One tip for a brick pile forge. Do NOT weld the frame together, even the best firebrick needs room to expand during heat cycles a bolt together frame is easy to access bricks for maintenance and gives sufficient room for expansion.

These have 8ea. Morgan thermal ceramics K-26 light firebricks. and 2 standard hard split firebricks for the doorways. It is all held together with all thread rod to allow 3D adjustability. The 1/2" T burner is the heat. I took this pic less than 5 minutes after it was lit the first time. None were kiln washed but lots of guys did later. A number of professional bladesmiths in the club put their "full size" forges away and may still be using one of these.

I would've done a few things differently but it WAS designed by committee at a club meeting. I'm darned pleased with them

Frosty The Lucky.

And, of course, drilling the hole for its burner is easy through those soft Morgan K26 bricks. You can drill with an old spade bit, or a worn out hole saw.

If you wanted to you could scratch holes with your fingernails. 

Frosty The Lucky.