Building your own forge
Mike asked us on a call whether or not we had any case studies or examples from people who had built their own forges now that Blacksmithing, as a hobby, is becoming more popular. What a great idea!
Please see below our very first "Clients feedback blog post"
Thank you so much Mike for sharing.
Firstly, the instructions are quite bare but mostly good enough with a bit of thinking. My stick welding is OK and I used this project to learn TIG. My general understanding of getting good results with TIG cost me a little time and frustration as well as some damned awful, porous welds. So please accept my apologies for the laughable welds.
I would recommend anyone without sandblasting equipment invests in some plastic sheeting and 20 litres of vinegar. It saves a huge amount of mess, discs and general pain to chemically strip the mill scale from the plates and angle iron. I only started doing this halfway through and wish I’d done it from the start.
In all the images I saw of the back bosh there was a drain plug at the side. I decided to make a threaded boss (M10) and welded it on the outside of the base but also welded it on the inside to prevent crevice corrosion and leaks later. I then proceeded to tack up the corners as per the instructions. With the Tuyere bolted and fitted in place. The bolt pattern isn’t quite logical and for about 5 minutes I was scratching my head. Everything was OK though.. just rotate the flange until all holes line up..
Once it was welded up I leak tested it with water by setting it on blocks at all angles so each weld was in turn tested. There were multiple leaks. So I marked each leak with a sharpy pen, emptied the water, dried the tank, inspected the suspect areas, ground back and rewelded.
I repeated the process until no leaks were seen. I do not recommend anyone shortcut this process and just assume the welds are watertight. I did this 3 times until I was happy. I then repeated it again with vinegar to pickle the welds and make sure no oxides or junk was blocking a pore.... just one tiny leak.. perfect, grind back, weld test again.. The tank is now finished.
I then moved on to the firebox. Aligning the pieces to overlap very slightly when plate is never completely flat was a pain in the butt so tacking carefully and taking your time is important. Put nice big tacks at each corner and then small tacks where necessary to pull the plates into line where needed. No bother all good. I used TIG all round the outside but stick to put a nice fat weld around the base for strength.
When welding the angle iron on that goes across the base of the firebox, be very careful of heat input. The difference in metal thickness makes this a little tricky as I discovered when my tacks broke, the angle iron turned into a banana and the whole firebox twisted... Time to leave it.. drink some beer and contemplate the error of my welding ways.
The next day I cut off the banana angle iron, ground back all the welds, picked up a hammer and carefully beat the firebox straight. Using some bar stock I had, I replaced the angle iron and then went to pickling the firebox... I had set up my pickling trough after I started welding the firebox so this was not ideal.
As can be seen the vinegar does a fine job of stripping off the mill scale, although in sub-zero temperatures the angle iron took some persuading to come clean (soak for 24hrs, scrub, soak for another 24 hours).
Once pickled spray. I used simple zinc based black spray for the sides and heat resistant paint for the base.
The smoke hood presented a few minor head scratching moments, not all the folds are fully folded enough. They were easily persuaded into alignment by using the vice as an edge and a hammer to increase the bend by a couple of degrees. Again, take care when aligning all the pieces of the jigsaw to note which pieces need a little extra fettling. I am sure this saved me a lot of issues later because once the sides were tacked on the top very nearly fitted exactly. With only a small gap that needed filled rather than welded.
I then Proceeded to fully welding Once welded you can then grind back for nice sharp edges or gently rounded edges whatever the skill level may be of the person fabricating. I went for gently rounded edges.. Then paint with heat proof paint inside and out.
The major components are now all fabricated and it’s time to drill the holes for the legs in the firebox. Easy enough. For the back legs I just noted which holes were the same as the front legs and used the front legs as the template. This worked perfectly. The little bracing frame welded up no bother, no fettling required. Just match drilling holes where necessary.
I welded up the shelf and aligned it with the back legs. It was too narrow to be bolted on the outside of the frame and the existing holes made no sense to me so I just welded it into position. To make life easy I welded it with the forge lying on its front, lay the bosh on the firebox so the holes lined up, made some scribe marks and took measurements. I wanted it to be a couple of mm low so I could have it sitting on a plywood base and shim so it was slightly tilted down to prevent air getting trapped in the tuyere. Then I mounted the bracket for the air valve.
Once that was done it was time to strip it down again and paint the frame in zinc based paint and mount the air valve. The hose supplied was exactly an inch short but I made it work and the air valve is not as aesthetically pleasing as I would have liked. I could have easily ground the tabs off but it was cold, no-one will see it and I needed a hot brew so.. it stayed the way it is. It also mounts on the wrong side for my workshop layout... but I’ll think of something.
Overall, If you want to progress past a little gas forge and the rather simple act of making knives then this is the obvious step to being able to make more complex things (things with bends in them!).
It is not cheap. By the time you have paid for all your consumables (argon gas, welding consumables, paint, discs) you’re not saving a huge amount over just buying the forge. If you don’t have a TIG capable welding machine or a MIG (NOT gasless MIG, ie fluxed core... it’s too messy) already, then definitely just buy the pre-built forge unless you want to learn to TIG/MIG anyway.
If you can afford the kit forge and build it, you can afford the pre-built version with the full experience and quality of AWB, a powder coated finish and a warranty... BUT, where’s the fun in that
Evenings spent in the freezing cold garage, with cups of tea gone cold before I could drink them as my wife complained about me being completely absorbed in my latest project.. Haha Pure gold!
Having a Traditional coal forge, as a hobbyist, is a great way to further understand how skilled a blacksmith truly is. I think I can work my way round an anvil and do certain things but I am constantly amazed by true artisan smiths and what can be created using only fire, hammer and tongs. This is the next step in my journey in that understanding and I am very much looking forward to it.
If you've brought a product from us and want to leave some feedback or tell us about your experience, please email us at email@example.com and you can then be featured on our client feedback page.