Buzzkill

FWIW, I and others have used the same instructions and design to build 1/2" versions of the Frosty T burner. There are corresponding changes to dimensions of other parts though. I was able to forge weld just fine with that burner. The temperature you reach is also affected by the tuning of the burner and the size, shape, and heat holding capability of the forge rather than strictly the burner size.

It qualifies in my humble opinion, but regardless of what we call it, it does interest me. I'm curious about how long you've had it in use and if you've attempted to reach forge welding temperatures with it.

You probably need to edit that last sentence Mikey, but I have to admit I was shaking my desk with silent laughter.

When I was looking into building a power hammer initially I looked at anvil mounted options like that. I'm fairly sure those use industrial grade sewing machine motors for power. I didn't have any plans so I kept making changes and the hammer kept getting bigger until I ended up with pretty much a full size tire hammer. Since I am limited on space I made it mobile with removable wheels. I don't bolt it down to anything, but the base plate is 20" x 24" x 4" so that weighs in over 500 lbs by itself. I don't think I'd try to use it on a plywood floor. The one you're talking about shouldn't be a problem though.

I have virtually no experience in this area, so forgive my question if the answer is obvious to you guys. If you get meteoric iron and then go through all the time and trouble to remove all the elements which make it rare/unique in the first place then what is the benefit of using it as an iron source? Why not just start with some ore which has the elemental content close to your desired product? I get the cool factor, but to me it kind of ceases to be cool if you change it so much that it's no longer recognizable as meteoric.

Ric's user name is his name - Ric Furrer. In case you weren't aware, his work was featured in the Nova program "Secrets of the Viking Sword" where he used mostly period correct methods to recreate an Ulfberht sword.

May I suggest you peruse the following thread and perhaps contact Daniel C for some additional guidance? He hasn't been on here for several months, but if a PM goes to his email he might respond. https://www.iforgeiron.com/topic/53084-first-crucible-steel-run-and-forging/ Ric Furrer is also a member here who has experience making crucible steel. Additionally, Steve Sells responded to the question of appropriate crucible with this: A6 graphite crucible In this thread: https://www.iforgeiron.com/topic/68384-crucible-steel-questions/#comment-740921 Hope that helps. Good luck, be safe, and share your results with us when you succeed.

I'd guess the passenger side. Being limbless makes it less likely that it would be driving, but you never know - they are crafty little buggers.

I was wondering if anyone else had experienced increased coyote vocals when the trains were near.

I had forgotten how many NARBs I've fiddled with in the past few years. One of them I made which was fed by a 1/2" Frosty T setup used 1/8" holes drilled into an insulating fire brick. I believe the number of holes in that one was in the high 60's and I concluded it could have used more holes. The one I'm using now has 44 holes that are 13/64" in diameter, but it's fed by a 3/4" Frosty T burner system. I'm interested to see how your next one turns out though. I really liked the idea of the floor mounted burner in a D shaped forge, and it did perform well, but the loss of so much floor space changed my mind so I went back to a side mounted NARB for my latest build.

A normally closed solenoid for the gas supply should be more than far enough away from high heat to avoid damage. If the blower and solenoid are tied together then the PID system should work ok after getting it tuned initially from a fuel to air ratio point of view. However, generally speaking you want to leave the blower on for a while after the gas is turned off to avoid the potential for explosion in the mixing portion of the system. If the blower is left running without any fuel to burn, that will cool the forge fairly rapidly. For my electric furnace the "on" cycles tend to be really short as the system approaches the desired temperature. I'm not sure how that will play out with a gas and blower system. You may be able to run an idle circuit though where there is always a minimal amount of fuel and air in the right ratio and then the PID controller runs a second fuel line and blower (or blower setting) for "full blast" forging. You'd need a second normally closed solenoid for safety before both of the circuits though. I considered doing something similar early in my forging experience, but ultimately concluded there wasn't enough advantage for me to make it worthwhile. For most of the things I forge, "eyeballing" the temperature is close enough. I did build the aforementioned electric heat treating furnace for alloys that require more precision though.

This may seem a little counterintuitive, but I'd start by making sure the mig tip orifice was free of burrs and debris. We shorten the tips to help induce more air, but if there is any restriction or deflection of the fuel stream it can have the effect of inducing less air. If you did run a torch tip cleaner or something similar through the mig tip I guess it's possible you increased the orifice size a bit which could produce the effect you are seeing. Another thing to check is the axial alignment of the tip with the mixing tube. Sometimes things don't get lined up when we replace the tips as they were before we removed them. P.S. I know it's just a photographic perspective thing, but your first pic looks like the back wall of your forge is the propane tank and it's glowing. It made me shudder a bit when I first saw it.

The only one I found was 1075 and 15N20 at artisan supplies (dot) com (dot) au, but it's currently out of stock. Personally I use New Jersey Steel Baron mostly. I can usually get the width and thickness I want and cut to length myself. To me the steel is reasonably priced, but if you're used to cheap or free shipping it can definitely seem a bit pricey.

Is this a blown ribbon burner or naturally aspirated ribbon burner (NARB)? Is the mixing tube that feeds the burner horizontal or vertical? If the mixing tube is horizontal there shouldn't be much of an issue as TP said. The hot air has to have somewhere to go for it to be a problem. With a blown burner there are normally a few bends and turns in the air supply line so I wouldn't expect there to be any appreciable chimney effect. Most NARBs I've seen or built have the mixing tube perpendicular to the the flame face of the burner, so again not too much likelihood of a significant chimney effect. 250 degrees F is not much though in terms of forges, so if a component can be damaged at that relatively low heat you could have issues even without any chimney effect. What component(s) concerns you?

They are pretty light. Very similar in size and weight to the disposable CO2 cartridges used in air guns. This whole thing has far more PR value than anything else. As already stated, the amount of energy required to "recycle" or repurpose these canisters into blades far exceeds the energy that would be used to recycle them at the nearest scrapyard. Kudos to the guy for finding a niche and filling it though.

We've probably just about beat this to death, but here's another relevant tidbit: Excerpt from Metallurgy of Steel for Bladesmiths & Others who Heat Treat and Forge Steel by John D. Verhoeven (Page 69 if anyone is interested) "When heat treating to form martensite, toughness is also enhanced by fine grained austenite because it results in a finer lath or plate size in the martensite. Again the same ideas apply. Rapid heating and repeated cycling produce smaller martensite microstructures. Grange [8.3] has presented a study showing the beneficial effect of small austenite grain size on the mechanical properties of 8640 steel. He achieved grain sizes in the ultrafine range of ASTM No. 13 to 15 by a 4 cycle process where the steel was austenitized in molten lead for around 10 s, cooled to room temperature, cold worked and then cycled again. A series of similar experiments was performed here on 3 steels to examine the effectiveness of thermal cycling alone, no cold working was employed. The steels were heated by immersion in a salt pot. Initially the steels were austenitized for 15 min. at 1650 oF and oil quenched in rapidly stirred oil. Then the steels were given 3 thermal cycles consisting of a 4 minute austenitization in 1450 oF salt and a quench in rapidly stirred oil. The grain sizes were measured with the same technique described by Grange [8.3] and the ASTM numbers before and after the 3 cycle treatment are given in Table 8.2. It is seen that ultrafine grain sizes were obtained."

In addition to the article I remembered, I did a little digging over at Blade Forums. The conclusion/consensus seemed to be that multiple quenches do indeed reduce grain size, but you can accomplish nearly the same reduction by normalization cycles before quenching. It didn't seem like anyone was a big proponent of the multiple quench idea when taking all factors into account.

I'll have to see if I can find this article I read a few years ago. In it they were discussing/exploring the concept of multiple quenches. They used the same stock and did single, double, and triple quenches on different pieces. After that they broke the pieces and took pictures of the resulting grain structure. There was a noticeable reduction of grain size for the multiple quenched pieces. However, I do not recall if they did multiple normalizations before the first quench or in between quenches. Personally I think that a single quench after 3 normalization cycles and then followed by at least one temper cycle of 2 hours is going to get most of the possible benefit out of a simple alloy steel. For me the added stress on the steel and increased potential risk for catastrophic failure of the piece with subsequent quenches is not worth whatever minor benefit that they might provide.

There's no way to give you a meaningful answer on the scissors. It's basically mystery steel unless you have a lot more information to supply. Most "normal" size scissors would not interest me due to the "work to useful steel" ratio to do anything with them. The big paper cutter is a different story entirely. If those are not plated it's a fairly safe bet that there's good knife steel there if it's all one solid piece. If it looks like there is an insert or different color steel on the cutting edge then that might be the only high carbon steel present. The older the cutter the more likely it is to be good forging material. If I had one of those I'd probably try to do something like an "expedient zombie killer" blade where you could still tell that it was from a paper cutter.

Just for reference's sake, the last NARB I made uses a .030 mig tip in a 3/4" Frosty T configuration. If you are using the same size tip in a 1/2" setup it's pretty much guaranteed to be running way rich. Based on the apparent size of your forge chamber the 1/2" T is probably the right size, but as Frosty said you need to drop back to a .023 mig tip to get it dialed in. If you're anything like me, once you get that NARB tuned properly you'll never go back to a single port NA burner. There are just far too many benefits and very few drawbacks imho.

The somewhat unfortunate reality is that often the handle sells the knife. Interesting shapes on the blade sometimes have that effect too, regardless of the practicality. Your average person doesn't know the difference in alloys or the proper heat treating steps. They know what looks good to them and/or feels good in their hand. Frequently those are the only criteria used when they make a purchase. It is assumed by most of these people that if a knife is hand made it is of superior quality compared to the mass produced knives, so they take that for granted. Serious collectors and enthusiasts do know the difference though.

I agree with JHCC. If you have any intention of building a power hammer in the future keep 6 to 7 feet of it intact. It's got a good amount of intrinsic weight, and if you fill a few feet of it with sand that would greatly add to the stability of the hammer in use.

So again we're all saying the same thing. The answer was designed to cover behinds, not impart accurate information. I get it. Many times on here if I answer a question it will be what or how I would do something rather than recommend a specific action for someone else to do. In that vein, if I had a Chili forge I would be comfortable using fire bricks or other objects to block off most of the front and rear openings while in use. I would have them completely open when lighting the forge, and I would always leave room for exhaust gases to escape while the forge was in use. With that criteria I would not be concerned about an explosion. Other people should do their own research and do what they think is best.

And I disagree right back Let's say your burner is already lit and you completely close off the openings which would significantly reduce or eliminate the ability of the NA burner to pull in air. In that case all available oxygen will be consumed and combined with the propane until there is no more oxygen available. At that point the forge chamber is saturated with unburned propane, which *can't* explode. All that could happen is burning of the propane any place it leaks out into the open air. Along with unburned propane, oxygen is a *requirement* for an explosion. Maybe it's possible to create that scenario in a forge with the burner still functioning, but I'm having a hard time seeing how that could happen. Regardless, I've never seen anyone on here recommend completely closing off a forge chamber while it is in use. If a door or other object that is used to block an opening has even a couple square inches of area to let out exhaust I can't see an explosion hazard forming. It may or may not be enough for optimal burner performance, but I personally would have absolutely no concern about an explosion. I'd recommend opening the ends of the forge and tossing in a burning piece of paper or something like that before turning the gas on any time a forge is to be lit, but especially once the temperature inside exceeds the combustion temperature for the fuel air mix the risk is so minimal as to not be worth discussing, in my opinion.

This doesn't really make any sense. Unburned propane simply cannot be introduced into the forge chamber just by adding doors. Propane, whether burned or unburned, is introduced by the burner, not the openings or the doors. Before a forge is lit there is certainly the possibility of trapping air and unburned propane together in the forge chamber which could result in a small explosion when ignited. However, if a burner is functioning properly it should be pretty much impossible to accumulate unburned propane and air inside the forge chamber in quantities great enough to cause an explosion after initial ignition. Even if a burner is running extremely rich the result would be flames extending from the openings and combusting in the open air, not an explosion inside the forge chamber. This strikes me as a statement designed to cover their own behinds rather than to impart correct information. Having said all that, what I said is my opinion based on my experience and understanding of propane forges. Take that for what it's worth.