rdennett

I thought about that, but the trouble is that the drive sprocket is on the inside of the frame. When I have seen people use bicycles for this, I believe they typically remove the back tire and rig up some kind of belt to go around the hub and a pulley on the axle of the blower. I am not quite sure what I have to work with there. Thanks, Rob

I actually have a copy of Weyger's book. Will the draft on that forge really create good forging temps? Also, I am not sure where to get PVC pipe over 6 inches in diameter. Would that be enough? If so, how long would it have to be. My bellows are roughly 2' x 3' and barely adequate. What volume of air does a bellows need to displace at a stroke assuming you aren't Superman? FYI, here's a link to a pic of mine on another forum: http://texasbushcraft.forumotion.com/t475p15-homemade-forge#3796 Thanks, Rob

What kind of pipe? What sort of dimensions do you need? Also, hand saws are great, but it takes a lot of practice to cut straight lines with one. I don't know if my friend is sufficiently adept with one to produce adequate parts. Thanks, Rob

Define not much money. I don't see them for much under $100 and that's before shipping. Thanks, Rob

A dry bag (sold at REI and the like) might be the ticket. These bags are waterproof and their tops do what the two sticks would do. They are also usually cylindrical. FWIW, Rob

I am trying to help a friend who is new to blacksmithing set up a forge where he has no access to electricity. I myself have a small double lung bellows that I constructed, but I was hoping to figure out a good way to construct a centrifugal fan from easily obtainable junk using minimal tools. A Japanese-style box bellows would be good to, but without a table saw or something that can make straight cuts in plywood, it is difficult to get the piston to work correctly. They also tend to be heavy and bulky and this may need to be portable. Right now, I am trying to figure out to improvise the bearing and pulleys or sprockets and shaft collars that would be required. My friend does have access to an auto body yard. Any good blowers in there he might look for? Also, any pictures or videos of homemade hand-cranked blowers would be awesome too. Thanks, Rob

Unfortunately, I am a Costco member . Thanks, Rob

I just wanted to report my status. I have had my forge up and running for a few weekends now. I was able to forge my first pair of tongs (actually not my first pair, but the first pair that are any good) as well as a spring fuller (which I don't think is going to work out), a chisel (forged but not filed), a punch and a sort of V-shaped bottoming tool. I was also able to get it up to welding heat (accidentally, but I will take what I can get). The forge is, as I have said, an upside-down lawn mower body with a Honda brake disc set in the hole where the engine would mount and attached with one bolt. The weight of the tuyere keeps things from moving around. The tuyere is made from 1-1/2 black pipe fittings and attached to the brake disc via a flange through existing mounting holes. I placed a piece of 1 x 1/4 inch strap between the flange and the bottom of the disc to keep the coals from falling in which is pinched in place by the tuyere mounting hardware. The gap has sort of chinked itself up with ash and charcoal dust. The legs are 36" pieces of 3/4" black pipe attached to flanges which are bolted to the forge body. On each side of the fire pot, I placed a fire brick on edge which allows me to pile the coals up nicely. For the bellows, I built a double-lung bellows about 18" wide by about 2 feet long and used marine vinyl for the leather. I mounted it in a frame and attached an old shovel handle for a pump. I use lump charcoal that I get at the grocery store for the fuel. I have to do a lot of pumping, but it seems to work pretty well. I have had trouble with it consistently heating up the metal, but I think that is a matter of the pile of coals not being deep enough. I should prep the coals by breaking them a little with a tamper that I have, but putting big chunks on top and letting them fracture on their own seems to work OK. Anyway, thanks for your help in building the thing. I have been playing with this stuff off and on since I was 18 (I am 40 now) and I finally have an OK setup (well, I don't have a vise, but I am thinking about that.) Thanks again, Rob

Anybody know where to get scrap in Austin, TX? I have a fair amount of high carbon stuff, but not much in the way of mild steel. I have some rebar, but that can be all over the map. I wanted to make some pothooks out of square stock for some Cub Scouts, but I have to make all the square stock. Thanks, Rob

Not sure about that, but I don't see what you are getting at. I don't have enough wood to make my own. Thanks, Rob

I am not really allowed fires other than in barbecues. My forge is basically a barbecue, and I am going to ask forgiveness rather than permission. Making charcoal would be too obvious, and anyway, I don't have the wood. Raw coal smoke might be a little obnoxious for the neighbors, so I don't want to go there. It is also not easy to come by. That goes double for coke and I understand you need a pretty thick firepot to use it, which I don't have (mine is an old honda brake disk). So my choices are charcoal, which I am all set up for, and propane for which I would have to outlay some dough. If I find myself burning up too much charcoal, I may go that way, but for now I am curious if there is a cheaper way to buy charcoal. Thanks, Rob

I was doing some forging this weekend and I used a lot of charcoal, approximately six or seven pounds in about 4 hours. I got it for 58 cents a pound from my local grocery store (it is lump charcoal, btw, not briquettes). I can't burn coal because of HOA rules and I don't have a good source for coke. I also don't have the wood to make my own and it would be a violation of HOA rules again, not to mention city ordinances. That said, can I do better than 58 cents/pound for lump charcoal? BTW, there is such a thing as natural briquettes which use starch to bind the charcoal dust rather than inert clays and such which lower the heat output in common briquettes. These are supposed to burn hotter for that reason. Does anyone have experience with them? Do they beat my price? I live in Austin, Texas, btw. Thanks, Rob

Richard Finch mentions this process in his books on welding, and relates a story of cutting some exotic alloy used in some aspect of building the space shuttle. He stated that it took an hour to cut this with a band saw and expended a $100 blade. He felt that the job could have been done in five minutes with a $5 Cronatron rod. I was unable to find any mention of this on the web and the only arc-cutting process people seem to know about when I mention this is air-arc gouging. Have any of you heard of magnesium arc cutting? Thanks, Rob

Deleted. Duplicate post.

Well, the pile was about 3" deep, the bellows are about 18"x24" double lung bellows connected to a 3" dryer duct connected to 1-1/2" (nominal) pipe fittings which are attached to the bottom of the brake disc with a piece of 1"x1/4" strap acting as an air grate, so say about 1 in^2 worth of air hole. I can't really tell where the hotspot was, but I put the tip of the stock I was trying to heat about halfway down into the pot. Assuming adequate air flow, what would the effect of a higher pile of charcoal be? Will it increase the heat significantly or will I just burn up more fuel? Thanks, Rob

I got to have some fun last weekend in the forge, but it doesn't seem to get quite hot enough. The fire pot is an old brake disk about two inches deep and I use lump charcoal, NOT briquettes. I stuck a piece of scrap steel about 3/8" in diameter into what appeared to be the hot part of the forge and pumped the bellows for a while, but I never did get it up to welding heat. I got it up to about orange (although it was a little hard to judge), but it seemed to stay there. Is this a matter of my fire not being deep enough (it wasn't much deeper than the fire pot), not enough airflow or not enough patience. My experience is mostly with coal forges, so I am basing what to do on that. Thanks for your help, Rob

How long did it take you to complete the first exercise? Thanks, Rob

Has anyone here ever practiced the flat-filing et al. exercises such as those listed in Weyger's Complete Modern Blacksmith? I understand that at one time, a metal worker coming out of a trade or engineering school had to be able to fashion a square hole in the exact middle of a square plate and produce a square bar that could slide through the hole with no light showing (and apparently, this was a test for employment for certain Ford Motor Company employees). A co-worker of mine who got her E.E. degree in India says that this is still a part of the curriculum there. I am sure you professional smiths have better things to do with your time, but has anyone else tried to do this? Thanks, Rob

I am using some lump charcoal I got in the grocery store for forging. At the end of a session, I can't just spread it around like coal because it will continue to burn and leave me with nothing but ash. I tried sprinkling a little water on it, but the next time I used it it sounded like the Fourth of July inside the fire pot. My most recent test was to put the hot coals into an old popcorn tin I have and put the lid on it. When it cooled, there was charcoal in there, but a bit of ash too. Is there a better way of conserving charcoal? I do have a smaller tin which should have less air for the coals to use. Is there a better way? Thanks, Rob

I just noticed that there is a separate forum for heat treating, so this post should probably go there if the mods want to move it. Thanks, Rob

I read (in The Complete Blacksmith if memory serves) about a method of quenching water-hardening steels using a squash or melon cut to approximate the edge profile by simply sink the hot edge of the steel into the fruit. Has anyone ever tried or had any luck with this method? Thanks, Rob

Because then I have to buy the wood and canvas. I don't do this professionally and I try to avoid spending money if I can. If I were going to spend money, I would search for a Champion blower or something like it. I already have a pair of double lung bellows, but I think they are too small. Anyway, whether I am making a double lung bellows, a Japanese bellows, a water bellows or whatever, I am curious about how much air the chambers are expected to displace in a single stroke. I calculated that for a 350 cfm bellows, I would have to displace 35 cf of air per stroke assuming 10 strokes a minute which isn't particularly achievable with 5 gallon buckets which hold less than a cubic foot. However, the water bellows pictured in the link aren't much larger than a 5 gallon bucket and yet they work, so I don't think I am doing the math correctly. Any thoughts? Thanks, Rob

Can I do a bump? Thanks, Rob

Or put another way, what should the displacement be for each chamber? Thanks, Rob

Yeah, I had seen the water bellows before, but I am not sure where I could scrounge the big barrels, nor do I have the space for them. My valve idea for the double-chambered version was more complicated. The squash ball is a neat idea. Thanks, Rob