28" wood / coal forge build

For 55 years I have wanted my own forge for the past 50 years I have made do with either a rose bud on a torch or tossed together small temporary forges when I needed one.
A while back I had to replace one of my 8n tractor rims because the old one would not hold air if I wanted to mount up tubeless.
What better use for an old rim than to make a forge out of it. Actually I don't really have the time to build a forge right now, with trying to mine and haul fill for my shop but I have an excavator with a broken drive and a bent drive sprocket that if I had a forge I could repair the drive then use the excavator to mine with and either the loader of the backhoe or the 863 Bobcat that I am repairing to haul and level the fill with so I said BUILD THE STUPID THING frank and be done with it at the very worst you can use it as a means of heating the shop next winter LOL
Ok 28" tractor rim salvaged from my 8n
the bottom of the forge is a 26" diameter 1/4" plate the previous property owner used as a lid for his burn barrel
the legs were taken from my stock of 100s of salvaged sprinkler down pipes
the apron was made out of a piece of auction scrap I bought years ago
that is the basic list of materials for the forge itself More about the toyere later
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It seemed like a good idea to remove the rotted out band
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Starting the apron
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after welding and grinding the welds I used my needle scaller to give it a hammered effect
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drilling the air holes for the toyere I decided that I wanted an iris for air control and flame modulation this is why the holes are drilled in a spiral
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Shown here the iris is closed leaving only a single hole exposed
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Open phase 1
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Forge post 2
Open phase 2
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open phase 3
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full open
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the blades of the iris are made from bed frame angle left over from the battery box hold down project
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The main body of the toyere will be this 14" car rim
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with the center removed the iris blades open all the way to the edge of the rim when fully opened
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I really should clean the torch tip shown here the second bead of the rim is removed
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the center is placed upside down
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Requiring a way to open and close the iris blades I selected these used bolts and welded them together to give me the offset I needed to make them center over the pivot of the blades
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showing the control rods welded to the iris blades
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Forge post 3
showing how the center is going to be fitted over the control rods
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Hammering out the center on Moilneer (Thor's hammer) the name given to what I use for an anvil by my wife
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the lug hole welded up and the cone shape started for the center of the toyere
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final shape
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More to follow tomorrow

So far not getting much done today
Have the cone welded to the toyere housing and the slots of the rim welded up where the center piece was riveted to it. Everything is roughed together and before I can go further to tube around the iris blade control stems I need to make the bolting clamps to hold things in place then it is all about some much needed clean up to the welds
Initial fit up
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welded up
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this pic shows a better view of the legs there will be some bracing but this can not be done until I have completed the toyere and the iris controls
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I did get a bit more done in-between having my mechanic neighbor come over for a chat and before the storms started to set in
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quite a bit of progress today all things considered
First off I had to make a retaining ring for the iris blade control disk
the retaining ring is 1/8 by 3/4" flat bar bent the hardway. I used my bender roller to accomplish this
https://www.homemadetools.net/forum/...041#post134119
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setting up for offset drilling of the iris blade stem support sleeve
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the retaining ring the stem supports and the control linkages are now in place
I just have to weld on some bolts to the control disk then make a flange and "T" for the air supply and the cleanout of the toyere then the underside will be pretty much done
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Jesus, Frank — you da man! There's some serious vision, design, and engineering went into putting that together. Not anything like I'm used to seeing in a "wheel forge."

I had to Google '8n'... And found this.

https://youtu.be/a05lKnwLCnQ

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Originally Posted by Scotsman Hosie

Jesus, Frank — you da man! There's some serious vision, design, and engineering went into putting that together. Not anything like I'm used to seeing in a "wheel forge."

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I went overboard in some areas and underboard in others.
One thing I would have done differently had I taken the time to think it through while I was building it is the way the iris blades are connected.
At the start while figuring out their placement shape and pivoting at first I had thoughts of simply extending a flat tab out from the end of them but they go through more than 90° of rotation, this would have required some seriously long slots in the perimeter of the toyere housing up next to the bottom of the forge. Had I done it that way it would have been next to impossible to get a reasonable enough air seal in order for the blower to be able to deliver enough air through the bottom of the forge to create a good burn.
Now looking back at it I see it would have been much easier for me to have not mounted their pivots to the forge bottom which inturned caused me to have to make the gilflirted offset control rods so I could make them rotate concentrically to the mounting studs.
Once I struck upon the idea of utilizing the 2nd smaller rim as the housing after I cut out the center I had to figure out how to go from a 9 inch diameter hole down to say 3 1/2 inches for the ash drop and the air delivery this was when I cam upon the idea of inverting the center and welding it back in place but I wanted it to have a continuous inward slope which meant forging it to a cone shape, I think this turned out well in keeping with how I wanted the results to be, the gradual deep cone shape will insure good ash flow downwards the guide sleeves for the iris rods and will allow minimal air leakage.
Where I went radically overboard is in the complexity of the stupid build. first off the mounting of the toyere housing could have just as easily been accomplished with only 3 tabs and 3 bolts I elected to use 6 tabs and 12 bolts simply because I could and besides how else am I ever going to use up over 400 lbs of 3/8 nuts in my life time given that I am not currently involved in production manufacturing any more .
I could have as easily used 7/16 , 1/2" ,5/8 or even 7/8" nuts as I probably have similar quantities of those as well.
After looking at this thing what I could have done was to have mounted the iris blades on a long straight stem then used a loner sleeve and had them mounted to the housing itself this would have greatly simplified the build and if I find out later on the offset stems give me problems it will be easy enough to modify

Awesome piece of work! BUT, I can't tell you how much I was looking forward to seeing a video of your forge in action at the end of your posting!

So.... how about a video?? Please??

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Originally Posted by JoeVanGeaux

Awesome piece of work! BUT, I can't tell you how much I was looking forward to seeing a video of your forge in action at the end of your posting!

So.... how about a video?? Please??

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I rarely do videos unless there is a particular point I can not stress any other way such as a wrong sound coming from an engine.
I find videos are more of a waste of time than anything else. There is rarely anything that I do using only 1 hand and that doesn't leave one free to shoot a video.
I don't even bother to watch 90% of the videos here on HMT and when I do watch them it is usually at 2x speed slowing only to catch a particular bit of content. Entertainment videos excepted.
But who knows once I turn it up right get the fire clay mixture in place and the a temporary blower connected I just well might make a video ot it heating up and show the operation of the iris valve. I bought a 50 lb bag of charcoal this morning to use as a test run. I'm not ready to shell out $300.00 + $400.00 shipping for a 2,000 lb pallet of coal just yet when 1.6 tons of hard mesquite has the same potential total BTU output as a ton of Bituminous coal or anthracite coal of course bituminous has more Sulphur and other impurities than anthracite but it is quite a bit cheaper
I might find that converting my wood into charcoal will give a lot better results as well, because many of the impurities such as creosote and moisture gets burned away in a pressure cooker of sorts.
I have a single particular job which requires the use of a forge and the job would have been too large for a smaller forge and I didn't want to have to rig up 2 #10 rose bud torches and burn up 2 bottles of oxygen and acetylene just to heat it up. I have been putting off the job for 5 years now because I didn't have a forge or any scrap materials to build one the size I wanted.
Once it is finished and tested I will have to build a hood for it for fume extraction. If for nothing else the forge could be used to add some heat to my shop next winter assuming I get sides and doors on it by then

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Originally Posted by Frank S

I went overboard in some areas...

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Happens to me all the time — unless I happen to catch myself. Simpler is just about always better. But you tend to get into the Tao of the hands-on build — which is 90% of the pleasure. And I've rarely cranked out anything that didn't suggest any number of possible improvements. Same excuse — using stuff on hand.

Still, it's vicariously fulfilling — to see the finished product, being created by cut, weld, and wire. Still watchin'.

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Originally Posted by Scotsman Hosie

And I've rarely cranked out anything that didn't suggest any number of possible improvements.'.

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Such was the case today as I had stated about the offset stems on the iris blades. Individually or moving a couple of them at the same time was simple enough however I noticed there was quite a bit of resistance getting all of the stems perfectly concentric to the blade mounting pivots was going to be a royal pain. Every thing was just too ridged even with reasonably slack tolerances hole to stem diameters was not going help much plus if for any reason I needed to disassemble the unit it would mean I would have to remove 28 nuts loose the adjustment of the blade positions before I could remove the housing then 12 more nuts to remove all of the blades if I wanted to remove all of them .
Did I mention I might own stock in Hillman fasteners/
Anyway I did need to disassemble the thing to clean out some welding slag lodged under the blades. So I have decided to go ahead and change the stems and the mounting of the blades to a less ridged method of mounting plus at the same time the mod will negate the need to disassemble anything other than simply removing the housing mounting nuts And yes I am keeping all 12 of them more because I like the looks of it even though they are under the bottom and no one will see them

today I came up with a real simple blade stem for controlling the iris blades but didn't get all 6 of them finished as I was not able to spend much time working on the forge pictures tomorrow

There is always something that gets in the way of completing some of my projects. and this project is no exception. If it was not repairing a aluminum fuel tank for another welder , rebuilding my 50 year old transmission jack or freshening up the automatic transmission I needed the jack for in the first place then re instlling it in the Dodge 2500 to having to completely rebuild a 42" mower deck for my wife's lawn tractor.
However I did manage to get the stems re made the only pictures I took of them are blurred so badly I can hardly make out what they are so I will just describe them for now until I take some new pictures after cleaning the camera lenz.
First I cut off all of the stems leaving about an inch sticking up then I remounted the blades with a single nut instead of using 2 nuts to lock them together I slightly deformed the shape of the nut to make it a friction locked nut. this left about half an inch of the pivoting bolt exposed. then I bored half of the threads out of 6 3/8 coupling nuts then screwed them to lengths of 3/8" all thread locking them in place with more nuts these nuts also serve as length or height limiters to hold the stems in the proper relationship to the blades and the toyere housing I then bent half round loops out of 1/8 by 1/2" flat bar and welded them to the sides of the coupling nuts now the bored out end of the coupling nut can sit over the exposed portion of the blade pivot bolts and the loops fit over the stubs of the old stems, so when the stems are rotated by the linkages outside f the housing the loops will force the blades to turn exposing or covering the holes in the forge bottom as required for air flow and heat adjustments. Maybe I will finish up the dodge pickup tomorrow and get it out of my way before my truck driver friend shows up Tuesday with another project to do to his truck. And wouldn't you know it this evening a mechanic friend of mine showed up with a 2500 Chevrolet with transmission problems so now I'm not only winding up with welding jobs that my welder neighbor can not do but I am going to have to rebuild a transmission for a mechanic because he can't do it. What's next someone showing up with an airplane? Sorry I draw the line on getting involved with the FAA

I've been thinking about this mechanism and I'm wondering if you had made the blades fixed in position and then made the fire bowl itself rotate to adjust the air flow would that work? It sure would be simpler to build. The support tray would have to be made fixed so that it extended over the upper edge of the bowl, the air chamber would have to be a reasonably close fit to the fire bowl so that there wasn't a lot of air leakage, and of course the blades would have to be close to the fire bowl holes.

Crusty I had given that some thought of having a plate under the bottom of the fire bowl slotted with spiral slots in the opposite direction of the way I had drilled the holes that is even the reason there is a center hole drilled there to actuate the dampener plate it could have had coarse teeth on the perimeter and a single pinion mounted to a shaft extending through the toyere housing. I even did a preliminary drawing of just such a method. the nice thing is this option can remain on the table should I find I am less than satisfied with what I currently have. The housing would only have to be slightly modified the blade mounting studs would have to be ground off and the plate made. Air leakage could even be less than what I may have with the current build design another possible advantage would be the mechanisms would be simpler plus it may make it easier to break up and pass the occasional clinker which could become lodged in the holes as the knife action of a single plate as opposed to individual blades could be advantageous.
However for right now I am going to run with the design I have Most things that I will even need to put in the forge are going to require wide open balls to the wall thermonuclear sized fires anyway

I do understand staying the course that you've already chosen because of the hours spent in getting to where you are now, and I tend to do the same thing. Mostly it was just a thought exercise on my part since I'd like to have a forge too, but there's at least 4 other projects in line before that one comes to the top. Truth told, I'll probably put a simple wood stove type throttle plate somewhere in my air line.