28" wood / coal forge build

[Frank S]

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??

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

[Scotsman Hosie]

I went overboard in some areas...

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'.

[Frank S]

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

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

[Frank S]

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

[Frank S]

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

[Crusty]

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.

[Frank S]

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

[Crusty]

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.