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I just built a box bellows but I haven't had a chance to get it hooked up and try it with a fire. What I can see already is that it's capable of huge volumes of air which makes sense when you consider the smelting the Japanese smiths have done. I watched a Youtube video series where the smith started with sandy soil and finished with a samurai sword. Thomas is correct that they require more force and focus to use. He's also correct that they are quite compact. I'm looking forward to trying it out because I suspect it will reduce the cycling time to heat the steel owing to the greater draft. I'm also curious to see how that affects my coal consumption. Right now I'm trying to figure out how to mount them on a mobile forge solidly enough to make the strokes efficient.

I made a set by dividing a 4' x 8' sheet of 1/2" plywood into equal thirds. That makes the bellows 4' long by 2'-8" wide. I just proportioned the shape so it looked right and copied it to the other two pieces. I used sheet vinyl (pleather) from a craft store for the covering and I can attest that it's pretty expensive. I think I ended up spending about $70.00 on material. I stapled, glued, caulked, and duct taped all the joints. The truth is, that unless you've got a huge leak, the tuyere has less resistance than the seams so there's little getting wasted. One thing I'd do differently are to start with multiple intake valves on the bottom and middle leaves. I started out with a 3" diameter hole in the middle and bottom leaves. That was WAY too much resistance. There doesn't seem to be a penalty to having lots of air flow, however smaller openings lead to valves that are easier to seal. Since my bellows were completely assembled I enlarged the opening to 7" square. I had quite a struggle getting the middle board valve in place. The second thing is that I'd use smaller valves since the big 7" square flap gets hung up on the top board if I "short stroke". I've got a 1-1/2" pipe outlet from my bellows, At the time I thought doubling the diameter of the output pipe would suffice for the input valves, boy was I wrong. Reducing the cycling resistance is a tremendous boon. The third thing is that I'd just make the bellows rectangular instead of tapered. The added work of tapering them doesn't do much but reduce air capacity and increase the perimeter you then have to seal. Plus the traditional shape is difficult to mount to a frame. I've got mine mounted to the stringers of my workbench which is also attached to my forge. The whole thing is too big but without a more compact bellows, I'm stuck with it. I've looked into the box bellows but there are two things I don't think I'd like. #1 is the clacking and scraping noise they make. #2 is that they quit blowing immediately. I like having the top chamber flowing while I get ready to remove the metal. What I do like is that they're compact, durable, and capable of very controllable air flow. Plus you don't have to pretend to be an upholsterer like I did to make them!

I had a similar question a while back about tomahawk holes. Thus far I've learned that using one long tool seems easier than it is in practice. I find it terribly difficult to cut all the way through in a single heat mostly because the end of the chisel/slitter/drift is so much higher than the work. I thought it would prove helpful for sighting myself plumb to the head but the trade off is an errant glancing blow to the tool tips the whole danged thing. I'm going to try Brian Brazeal's tool which is somewhat like a tapered slot punch. Being able to punch from either side keeps the eye nice on either end. One thing I've noticed is that experienced smiths are punching all the way through in one heat. Whatever makes your hammer blows more accurate and forceful should be first concerns. A common thread woven throughout a lot of traditional blacksmithing techniques is that efficiency is more about getting it done with less work than getting it done with fewer tools. When I first considered this hobby I was impressed by the enormous tool collections that most of the smiths had. Now that I've spent some time with it, I can see that making several simple tools which progress the work faster is better economy than making one "super" tool which at least in my case, makes things take longer.

Although I've only stuck a single weld so far, one thing I read over and over again in books is that the mating surfaces need to be rounded and aligned so that the centers touch first. The idea is that as the weld is pushed together, anything that shouldn't be there will get pressed out. I met a smith who added iron filings to his flux. He told me the filings will burn and sparkle just before the metal is at welding temperature. I don't know if he used cast, wrought, or pig iron for the filings. I'm not even sure if that would matter. I will say that his welds looked good despite all the sparkling. Good luck!

Maillemaker I started out with a heat gun that had a broken element which is close to a hair dryer. While anything moving air will work to a degree, it's important to recognize that air flow, not velocity is what's important. The hand crank blowers are much more like a pump than a blower in that they push a large volume of air with relatively slow air speed. After trying to use the heat gun and a vacuum cleaner, I came to realize that bellows were better for me. A Sheet of plywood and some second hand "pleather" coats from a thrift store are readily available wherever you live. I looked for over a year for an inexpensive hand cranked blower, the least expensive one I could find was $200.00 on e-bay. My bellows were roughly $30.00 in parts. One tremendously important thing about bellows; the cross sectional area of the valves must be large enough to allow rapid intake and evacuation. Several smaller valves grouped together are easier than one larger and hard to seal one. After building one set, I will probably move to making a smaller box shaped model for space savings. If you have the room, there are water bellows plans http://www.google.com/imgres?q=water+bellows&hl=en&client=firefox-a&hs=CkC&sa=X&rls=org.mozilla:en-US:official&biw=1920&bih=947&tbm=isch&prmd=imvns&tbnid=nEJAMG7OOMuLdM:&imgrefurl=http://www.garden-sculpture-art.co.uk/blacksmiths_forge_bellows.htm&docid=Lo-oRNmAimzUJM&imgurl=http://www.garden-sculpture-art.co.uk/Water%252520Bellows%252520Drawing%2525202%252520comp.jpg&w=600&h=487&ei=cUDJTouQF_TJiQKv5KX-Dw&zoom=1&iact=rc&dur=279&sig=117065086116668325303&page=1&tbnh=140&tbnw=172&start=0&ndsp=49&ved=1t:429,r:0,s:0&tx=105&ty=89, this seems like it's be very cheap if you can find old drums. Good luck and thanks for taking care of the scout tradition!

I started with a shop vac, went to a hair dryer, then to a furnace blower before I made bellows. Personally I detest the noise of all but the furnace blower. Along the way, I learned there's a big difference between air flow and air velocity. What seems to matter more in a forge is air flow, velocity just seems to quickly burn the fuel to make clinkers. If you look at the hand crank blowers used by blacksmiths they are more of an air pump than a fan. If you're at all electrically inclined it will serve you well to find a foot switch and a speed control for your blower. The foot switch should be set up so that the motor only runs when you're standing on it. That way you aren't wasting fuel while forging. The speed control makes a big difference getting the fire to behave itself. Building bellows with the help of IFI member input has been one of the best moves I've made. For what I spent cobbling the previous three together, I could have just built the bellows first off! Should I do it again, I think I'd skip the traditional shape and opt for a simpler square bellows box for a more compact arrangement. I like the bellows better than a blower mostly because I find the sound and the motion to be soothing. Another thing that helps a lot is a funnel shaped fire pot. I've heard of people putting clay into a brake drum to achieve that effect but I haven't tried it myself. The funnel shape helps the coke to "self consolidate" as it burns. Again, IFI has some posts about the refractory clay recipes folks have used. Good luck!

This weekend I was very fortunate to have a neighbor who welded up some plates for me to make a fire pot. My previous pot was a brake drum and the difference is impressive. My new fire pot is square around the edge tapering like a pyramid pointed down. The center has a 1-1/2" black pipe nipple that's has a pipe cap on it with a 1-1/8" hole in the middle. I laid out the pot so there would be a 6" deep bed of coals to the rim. Yesterday was my first fire in the new pot and even lighting it went better! I think the funnel shape of the pot helps tremendously because the fire "self consolidates" as the kindling burns up, the tapered sides bring the coal into the heart of the fire. With the square bottom of a brake drum, I found that my fire was more pancake shaped. Once the kindling burned up, the fire would sometimes collapse and choke itself. It took much longer to get it started and it took a lot more effort to get it shaped so I could actually get the metal hot. I will say in hindsight that cutting and welding the 1/2" plate that I had scrounged was very likely more expensive than buying a new made fire pot. Again, I'm very grateful to my neighbor for all of his help.

Once again, thank you all for your help!

Grant, The tool I made is just about a foot long so you're spot on! I find shorter tools hard to told with the heat of the blank so close to my hand. Plus being longer, I can sight it better to keep it straight up and down. I see your point that making a combination tool makes it useful for only one thing whereas if I made two tools, I'd have greater range of utility. Thanks!

Continuity testing won't tell you if a winding has shorted to itself. What works REALLY well is to smell the motor! Burnt insulation is a smell that won't fade for years.

Steve Sells is absolutely correct, I too am an electrician. A relay is the most appropriate answer to your problem.

Thank you all for your replies, I have a few questions. I thought a slitter offsets material but the slitters in Brian Brazeal's posts appear to be creating a slug. Does this mean his slitters work through both upsetting and punching? I understand that the slitter I used was oversized for the drift which is why the slit extends beyond the drifted hole. Wouldn't a drift that tapers to a slitter solve this problem? Is there a reason that this is done in two operations, slit/punch then drift? I'm curious because a drift is a very specific purpose tool which would lead me to think they're nearly always custom made. Is there a reason that it's not appealing to make a combination slitter and drift? Petere, Are you saying that a drift has to be 40% smaller than the intended dimensions of the hole? All of the books I've read have failed to provide anything like the detail in your post. I really appreciate you taking the time to explain it to me. Frosty / Grant, my drift is teardrop shaped in cross section and tapered lengthwise similar to a pickaxe. I'm trying to make it similar to this: http://www.coldsteelknivesdirect.com/riflemans-hawk Rob, I'm not sure I have the skill to upset the material on the sides only. But since it's already messed up I can certainly use it to practice! Again, thank you all for your replies.

I'm a novice with very little time or tools. I've been trying to forge small tomahawks out of a scrap digging bar. My intention is to end up with handle similar to a pickaxe where the handle enters the top of the head and doesn't require any wedges etc. So far I've been able to punch one head which I later tried to drift to the correct profile. This took me most of a day and I wasn't really happy with the results. I think my drift was entirely too cone shaped and it needed to be smaller in circumference. For my second try, I started by using a chisel to start, figuring I could drift the hole faster. I also made a smaller drift which had less taper to it. While it took me half as long, my drift failed to utilize the entire slot cut by the chisel. The handle hole is shaped like a tear drop with a line extending lengthwise on either end. At the end of the day I decided to try and use one large piece of bar stock I had on hand to make a new tool. I've shaped it exactly like a tomahawk handle, and it tapers to a chisel point. My thought is that I can use one tool to cut, drift, and finish the handle hole. I've never seen anyone else using such a tool which leads me to suspect my inexperience is keeping me from seeing some missing detail. The whole reason I thought to make the tool was to ensure that I didn't have to worry about tool sizes being incompatible like my current chisel and drift. The bar stock is from the same digging bar which I believe is medium carbon. Why drifts aren't made with cutting / punching faces on them?

Fosterrob, I believe you're thinking of one type of AC motor. DC motor torque curves are VERY vertical meaning they start with high torque at low revolutions. Locomotives are Diesel generators running a generator to power DC motors. DC motors have a few advantages and several disadvantages. The advantages are they have low rev torque, high power to weight, and precise speed control. AC motors are less expensive because with a few exceptions, they don't have commutators, brushes, or diodes to worry about. With the advent of Variable Frequency Drive, industry largely moved towards AC motors to save costs on applications previously dominated by DC motors. There is a hybrid design called a universal motor which is a combination of a DC and and AC motor. These are frequently in power tools and bench mixers. While limited in horsepower and torque, they make up for it in versatility and reasonable cost. The least expensive option is generally to use a simple AC motor of sufficient horsepower. One idea that hasn't been mentioned is to add a flywheel. This would tend to counteract bogging down without requiring greater horsepower.The down side is that it won't help you for a sustained hogging out operation. When it comes to grunt, regardless of speed, the AC motor must have higher horsepower ratings. With higher HP ratings come thicker winding's which can handle more heat. Heat breaks down the insulating varnish which leads to winding failure. If you can afford it get a TEFC which means Totally Enclosed Fan Cooled. These have sealed bodies that don't allow debris or dust to enter the housing and break down the bearings. They have cooling ribs on the exterior and a shaft mounted fan that blows along the exterior of the housing. Look for electric motor rewind shops. Often motors under 25HP are simply replaced because Chinese imports are less expensive than paying to rewind them. Since most folks don't know that, the shops end up knee deep in dead motors. Often they'll take quality motors like Baldor and rewind them for resale. Generally they price the re-winds on par with the new Chinese. Depending on the shop, they're a better deal if they've got new bearings in them.

Lead anchors will work fine. The whole point of a fireplace crane is to put a vessel at the focal point of the heat which is the center of the fire. If it reached boiling temperature at the side of your fireplace, you'd be making a hook instead of a crane. The lead in a lead anchor is only the outside, the inside is steel which is unmercifully forcing the lead into the hole you drilled. There's a certain amount of shielding done by the bolt head and bracketing which will reduce the temperature of your lead anchors to well below anything remotely worrying. If you were really worried about it, you could also buy steel expanding type anchors, same notion as the lead anchor, just no lead.

Well folks, I cut new inlets that are 8" square. The valves are flaps of vinyl that are 10" x 12" with the long side the being the side fastened down. My new problem is that the valves aren't sealing at all. I'm thinking of gluing a piece of sheet metal to the vinyl flap to stiffen and hopefully seal it better. Before I tear into it again I'd like some input. Thanks in advance.

I built the center and bottom board identically so the inlets line up with each other. Sadly, they are both simply a hole with a vinyl flap attached on the inside. I'm thinking that I'll make a square inlet valve that's mounted to a small frame. That way I can saw the square opening, slip the valve through at an angle and still have the frame to fasten to the board. Now that I've made this mistake I'd definitely make the valves removable the first time since it's much easier to fix mistakes when things are adjustable.

I would imagine a lightweight turbine oil like what comes in the Zoom spout type oilers would work great!

Good observations Rob Brown and Nakedanvil, I've got a 2-1/2" drill bit which is why I've used that size. Sounds like it's time to step up the size to get closer to what's being recommended. Francis, the centerboard does have a valve that's the same size as the bottom board. I made my bellows so that the centerboard is always stationary. The support's are connected to it. The top board may end up needing a weight on it to keep up with the bottom bellows once the new inlets are added. Thankfully that's easy to accommodate since I can just store hammers there until I've got the desired effect. I've very relieved to hear that the fix is so simple. Thanks again for all of your help.

Thank you all for the insights. I only have one 2-1/2" inlet on the bottom and one on the middle board. It sounds like I need to add another one to each board. I was concerned that if the hole was too large it wouldn't work properly but I can't think of a reason why. I'll add the inlets this weekend and post my results. Thank you all for your help!

I'm looking for some sage wisdom to help a new guy out. I built a set of double bellows. They are 4' long by 2' wide tapering to the spout which is 1-1/2" diameter. The intake holes are 2-1/2" diameter with a flap valve. Both the bottom board and the stationary middle board have them. There's about 12" of movement at the back of the bellows. The fire pot is an automotive brake drum piped with 1-1/2" black pipe set up with the typical flange, tee, and trap. I've connected the bellows to the pipe with a section of flexible 1-1/2" exhaust pipe which is duct taped to seal on each end. I made a clinker breaker out of a towing ball that I cut down, drilled and tapped to allow me to mount it in the tuyere just below the flange connecting the pipe to the drum. The clinker breaker has about 1/4" on all sides to allow air flow around it. I'm using coke as fuel. The issue is that I can't get sufficient air flow to get the coke lit let alone keep it going. I tied a weight to the bottom board to get allow faster recovery. The bellows are covered with vinyl and there don't appear to be any major leaks. There is definitely air flow it's just not very fast. When I've put wood in to get the fire started, it pumps plenty of air to get it going quickly, it's just the coke never seems to get lit. Just to see what would happen I pre-heated some of the coke with a MAPP gas torch while pumping. Once lit, the best I could do was a dim orange, never yellow let alone white. Needless to say it went out quickly when I stopped pumping. I tried to mimic a set of bellows I saw working at a hammer in early this summer. They were only 3' long and it was easily handling the needs of the smith who was demonstrating forge welding with a coke fire. So that's it, I'd love your insights, thank you in advance!

I've been looking into it myself. There's a blacksmith on youtube who goes by "purgatory forge" and there's a couple of videos pertaining to making your own belt grinder. The most useful thing I've seen so far was where he took plywood and laminated it into a 2" thick plate then spun it to trim it into a wheel. The cost of larger diameter wheels is prohibitive but he was able to make a 12" diameter wheel out of scrap. Speed control is a very significant feature that doesn't get much mention. Cheap motors will be faster running so it's worth thinking about pulley's or variable frequency drives.

Thomas, I kind of see your point but teepees were heated with a central fire, camp tents regularly have wood burning stove. Granted my feet aren't likely to get much heat but some would certainly get trapped by having a roof. Plus cold air would give more draft drawing the smoke and accompanying CO2 out the stack. Nakedanvil, I'll have to check those out since they sound like just the ticket. Thanks everybody for the replies.

Brian, We do get a lot of snow in Loveland but I figured the heat of the forge in a smallish space would make it more comfortable. Jake, Thanks for the information - good to know it's doable. MUCH less expensive than building a garage, plus it's portable for the summer hammer ins. Thanks for the replies!

I'm set up with a coal forge in the back yard which works fine when the weather is cooperating but the weather's turning cold. That got me to thinking about the tents I've seen blacksmiths using at hammer ins. Most of them were set up to serve as a wind break and a rain cover which I think would work pretty well but I'd like some input from folks who've used them in the winter. Thanks!