Frosty Posted January 13 Share Posted January 13 One of the guys in our club has been bringing his Mr. Volcano single burner to meetings for a few years now and it does everything we've asked of it. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
Brassa Posted January 13 Share Posted January 13 Glad to hear that Frosty! I'm excited to pound something out but taking my time getting the forge setup. Brandon Quote Link to comment Share on other sites More sharing options...
Mikey98118 Posted January 17 Author Share Posted January 17 Rotary, die grinder, or drill? It is generally better to employ a rotary tool for burner construction, and a medium power die grinder for forge construction. The Votoer 260W is an exceptional rotary tool; it has all the hoped for advantages; lots of power, smooth performance, and ergonomic design. But what makes it outstanding is its chuck. Keyed chucks are tightened gradually, by using the key in all three holes in turn: 1, 2, 3, 1, 2, 3…until the drill bit, or accessory shank is gripped much tighter than any collet chuck, or keyless chuck, can manage. Also, odd size shanks and drill bits cease to be a problem. Best of all is, a keyed chuck of this size will accept rotary tool accessories and die grinder accessories, too. This tool is small enough to do delicate burner work, and powerful enough to quickly do steel cutting on forge shells, angle iron and flat bar. So, why wasn’t a ¼” keyless chuck mounted on a rotary tool long before this? It isn’t easy to make a chuck this large, which is also light enough not to bog down a rotary motor with every startup; that will heat up the motor; shortening tool life. The answer is better machining, which is what this chuck has. This is simply a better chuck then is needed to run their Votoer 480 die grinder, which has nearly twice this tool’s power. This lighter chuck is matched to a more powerful motor than is available in any other rotary tool. This combination is good enough to do the job. The Votoer 260W is a medium-power die grinder (260-watts or 2.24 amps) stuffed into the smaller body of a rotary tool (2” diameter x 7-5/8” length); its weight is 1.84 pounds; a little heavier than most rotary tools, but lighter than some. This tool’s power presents no problem for two handed use, but 100 extra watts more than standard rotary tools is far from safe for single hand use. If you must use it one-handed for out of position work, reduce its speed. This tool has sufficient air ducts, but will still heat up, if run continually; this should not be considered a flaw, but a predictable design limit from a high amperage brushed motor crammed into a small package. My tool runs smooth as silk, with no obvious run-out. The keyed chuck closes to a minimum of 0.024” and opens to a maximum of 0.006” larger than 1/4”; its keyed chuck, greater power, and lower minimum speed combine to make this tool superior for a great variety of forge building tasks. You can use inexpensive rotary tool accessories, and also tougher die grinder accessories. ¼” mandrels are far stronger than 1/8” mandrels, which is important for faster surface cutting on equipment parts like flat bars, steel angles, and equipment shells. ¼” burrs also have far stronger shanks than 1/8” burrs; they can extend further beyond the spindle, without bending at high speed; that’s handy for grinding and sanding inside of tubes and pipes; understand that we are not speaking about extension in numbers of inches, but in added fractions of an inch, at full speed. Speed adjustment is from 5,000 to 31,000 RPM. Among rotary tools, die grinders, and micro-drills, few have this low a minimum speed rating, for micro drilling in mild and stainless steel. You will not find this product’s quality control equal to top of the line tools, which go for three times its price; but you will not see one of them featuring a keyed chuck, either. You should be prepared to deal with possible loose electrical connections; if you want guaranteed turn-key performance, look elsewhere. If you are willing to put up with possible inconveniences to get a tool with advanced design, this is it. Quote Link to comment Share on other sites More sharing options...
Mikey98118 Posted January 19 Author Share Posted January 19 Exhaust openings One thing backyard casters and blacksmiths both worry over is how large to make the exhaust opening(s) on their equipment. Too small and you have high back pressure killing burner performance; too large and you cannot retain enough heat to do your work. Of course, the closer to the "right" opening size your equipment is the stronger the forge or furnace can be built. Just don't confuse the right size for a “perfect” size. As long as burner output can by varied (turn-down range), there cannot be any such thing as a perfect exhaust opening size. The right size is what is needed to accommodate the burner's highest output (the highest you are willing to take it to). Variable is the optimal opening size; all other dimensions can be outright wrong, but are seldom just right, with a burner flame that can be varied. This is one of the many reasons for controlling exhaust flow with an external baffle wall beyond a large exhaust opening; thus, allowing the least heat loss through radiation, while maintaining optimal atmospheric pressure in the forge. Note: Include a protruding ring of hard cast refractory around the exhaust opening, to divert hot exhaust gasses away from the shell, where it will super-heat the metal. If you decide on a movable brick baffle wall in front of the forge, keep the bricks at a small distance from the exhaust opening, to allow hot gases to move up and out, between the opening and brick, while bouncing most radiated heat off of a re-emission (heat reflective) coating on the near side of the bricks, and back into your forge. Keep the stock entrance only as large as is needed to move parts through. This arrangement helps to slow the flow of expended gas in the forge interior to what is needed, and no more; as it gets close to the exhaust opening, the gas speeds up and through the opening; another desirable trade off. So, you are gaining hang time for the heated gas in the forge, and recuperative savings from bounce-back of radiant energy; a win-win situation. A baffle wall also minimizes infrared and white light from impacting your eyes and skin, improving your health and comfort. Quote Link to comment Share on other sites More sharing options...
Mikey98118 Posted January 20 Author Share Posted January 20 Doors: Maximum part clearance can be provided two different ways: One is with a hinged and latched forge door (stainless-steel toggle latches are your best choice); it should contain built-in interchangeable baffle plates (high alumina kiln shelves are perfect for this). A door makes building the refractory structures inside of equipment much easier, and permits larger parts to be heated than would pass through a narrowed exhaust opening. Best of all, it allows closely contoured movable internal baffles to be employed, which would not pass through a narrowed exhaust opening; this promotes the use of single burners for small pieces, saving money in tunnel, oval, and “D” forges, which are run by two or more burners; on these forge shapes, the door is a big step up from an exterior brick baffle wall; it should include a parts entrance that can be varied in size; for instance, with several round (or hexagonal) kiln shelves with different openings cut into them (for passing stock through); these can be exchanged, and held within a pocket structure on the door. These improvements do not all need to be seen to at once, so long as a hinged and latched door is included in the forge shell. On forge/furnaces, the door can be left as is, or can be attached to a singe pin hinge, and revolved out of the way. Sliding doors: Some people prefer vertical or horizontal sliding doors, instead of hinges. People usually employ the new insulating bricks as horizontal sliding doors. High alumina kiln shelves are seven times more insulating than clay fire brick, but not as insulating as the new semi-insulating fire brick now being used for pizza ovens and home fireplaces; but high-alumina kiln shelves are tougher at incandescent temperatures then the new bricks; this is a consideration for something you will end up shoving parts back and forth through. Exchangeable kiln shelves, with different part openings drilled and cut into them are fine, but building an elaborate system of moving kiln shelf parts to ape the ability of bricks to infinitely vary their openings comes under the heading of "gilding the Lilly." The additional energy savings it provides, probably is not worth the effort. Make up new openings in kiln shelves sparingly. Diamond coated and carbide coated rotary burrs (and diamond or carbide coated hole saws) are the preferred way to drill holes in kiln shelves. Friction cutoff blades (safest) and diamond coated blades (only of small diameter) are the best ways to cut out straight lines between those holes. A hinged and latched door, can also work on a box forge. Yet, movable bricks, trapped in an angle iron, or structural channel frame, will work out better than the hinged door. Furthermore, the channel frame works best, for sliding solid parts up and down on woven wire, and running through pulleys, and counter balanced. You want to coat the hot-face side of either kind of door with one of the re-emission coatings. You can use a formula of 95% zirconia silicate powder (crushed zircon) and 5% Veegum (or 5% bentonite as an alternate); this mixture makes a tough heat reflection coating for wear surfaces. The ingredients should be available in ceramic supply stores. Zirconium silicate can also be mixed with fumed silica to make a tuff and heat reflective coating on hard refractories, or on ceramic fiber products. There are other choices, Like Plistix 900F, but none of them are easily purchased in other countries. Zirconium silicate and bentonite clay should be readily available in pottery supply stores, in many places. Quote Link to comment Share on other sites More sharing options...
Mikey98118 Posted January 26 Author Share Posted January 26 Miniature angle grinders: A few years ago, 75mm (3”) angle grinders started being exported from China these were 285-watt 220V grinders, which were not only handy for light work (ex. auto mufflers and body work) but the ideal size, weight, and torque for safer surface cutting on sheet metal. Because they were 220 volts, they did not gain popularity, and stopped being offered after a few months. However, an improved version of them is making a comeback. These are still 220-volt models, but are a little more powerful (360-watts), and smaller than the original version. Some of the sellers also offer a box to plug them into, which changes 110V to 220V power, for about twenty bucks. You can find them listed on AliExpress by imputing “miniature grinder.” Up will pop the usual weak 12-vote cordless grinders, mixed with ads for these. Take your time reading through the ads; don't just jump on the lowest price, without looking at customer feedback. You will also notice that two of the ads include fittings that allow the grinder's spindle to be used as a die grinder... Quote Link to comment Share on other sites More sharing options...
Mikey98118 Posted January 26 Author Share Posted January 26 Of course, there is always the choice between types of tools for the two main jobs in forge construction. Medium power die grinders are most useful in building larger linear burners, versus rotary tools, which are a better choice for building tube burners (with their internal cuts into tubing and pipe for air openings), or small linear burners; either tool is less helpful in building forge shells, and stands than an angle grinder. However, the main job of that angle grinder is surface cutting in sheet metal, angle iron, and pipe. So, once again, enough power (285-watts to 360-watts) from a corded angle grinder versus 35-watts to 50-watts from a 12V cordless angle grinder. Finally, we might think about grinder stands, which can turn an angle grinder into a chop saw. A 3" grinder can only cut about 1/2" into a surface; no good for plunge cutting. The reason for that is that the grinder's gear head takes up a lot of room. Too bad we can't mount a 4-1/2" blade on it, right? But, maybe we can. These 3" grinders turn at 12,000 RPM, which is the right speed for a 4-1/2" cutoff disc; not the 19,500 RPM of cordless 3" grinders. To mount such a blade on them would make them nearly as dangerous for surface cutting with a standard 4-1/2" angle grinder; but mount them in a grinder stand, and the objection becomes irrelevant. Naturally, any stand you buy would have to be adjusted to work with this smaller tool, but the work would be worthwhile. Quote Link to comment Share on other sites More sharing options...
Mikey98118 Posted January 27 Author Share Posted January 27 Make sure that the stand you buy includes its own guard; some of them do, and others do not. Quote Link to comment Share on other sites More sharing options...
Mikey98118 Posted February 3 Author Share Posted February 3 Why Multiple burners? Heat management only begins with flame temperature. The reason burners are aimed on a tangent, is to cause their combustion gasses to swirl around equipment interiors; creating a longer distance from flame tip to exhaust opening. Obviously, a lengthened exhaust path increases the amount of its hang time. Thus, depositing more combustion energy on internal surfaces. What is not so clear is that the heat gained is not added by super-heated gases blowing an extra foot or two at high speed; it is due to their continuing drop in velocity over that added distance. Combustion gases begin to slow, as soon as they leave the flame envelope. The flames of two 1/2" burners will use the same amount of fuel to produce an equal amount of heat as a single 3/4” burner; but they will drop velocity much faster in a five-gallon forge or casting furnace; increasing efficiency, because their flames can burn faster/hotter without creating a wasteful tongue of fire out the equipment’s exhaust opening. Ditto for two 3/8” burners versus a single ½” burner in a two-gallon combination forge/furnace, or two ¼” versus a single 3/8” burner in a coffee-can forge or casting furnace. Because the parts and tubing these burners are built from cost less as their sizes reduce, it costs little more to make two smaller burners than a single larger burner. When heating small parts in a forge, further efficiency can be gained by placing a temporary partition in equipment interiors; separating them into twin spaces, and shutting down the rear burner. This is something that cannot be done with a single large burner, which is centrally located. Combination forge/furnaces require the forward burner to be shut down during casting operations, so that its flame is not wasted from being positioned too high up the crucible wall. Quote Link to comment Share on other sites More sharing options...
Mikey98118 Posted February 6 Author Share Posted February 6 A few months back 18V and 20V 3" angle grinders started appearing for sale, and since Makita and Dewalt had there own versions of them, they were to be taken seriously, despite there high prices. However, these are obviously designed strictly as cutoff saws; using them as grinders would be way too awkward. There are now 18V versions of the handy little 3” angle grinders, which were only available in 12V, previously; this fills the gap between under-powered 12V angle grinders and well powered but bulkier 3” 220V corded grinders. You can find them on AliExpress, But Harbor Freight Tools now sells their own brand of them. Of course, the nice thing about choosing the HFT model, is that you can take a lemon right back to their store. At present they are selling the Bauer brand batteries for the same price as the grinder; if you buy the battery during their sell, they have a list of tools for it you can get free. The 3" grinder is on that list. Quote Link to comment Share on other sites More sharing options...
Mikey98118 Posted February 9 Author Share Posted February 9 Using an AC 110V to 220V adjustable voltage converter (4000-watts and $23 through Amazon.com, or eBay), will allow you to plug a 220V tool into a 110V power outlet, and provide speed control, without engaging the built-in speed control circuit on a power tool (which has no fuse to protect it from damage due to overheating; which these do). Quote Link to comment Share on other sites More sharing options...
Mikey98118 Posted February 14 Author Share Posted February 14 Just don't weld it! Many people form the opinion that they must be able to weld, to build a forge. I suspect this is because it is common to see commercial forges that have been welded together. So, if welding isn't the best way to attach forge parts to each other, why is it so common? Welding is common in commercial forges for the same reason it is common in small steel shops; if you already have the equipment and the know-how, it is the fastest way to stick stuff together--period. It is not the best way to assemble a forge; it is more often than not the WORST WAY! But, monkey see, monkey do... Even if you have a welding machine, do you understand what part is safe to weld, and what isn't? There is a lot more knowledge needed for proper welding technique than just how to make a pretty weld bead. If you aren't familiar with how metal moves during welded, and afterward during heating cycles, avoid welding like the plague! There are machine screws, sheet metal screws, and pop-rivets to stick those parts together with, and all of them allow a certain amount of movement, during heating cycles; welds do not. Quote Link to comment Share on other sites More sharing options...
Mikey98118 Posted February 14 Author Share Posted February 14 So, how would you know what fastener to use and how to use it? Just Google "fasteners." Then Google each fastener that you are interested in; some provider while list instructions on pop-riveting, etc. in order to encourage you to purchase their product. Quote Link to comment Share on other sites More sharing options...
Irondragon Forge ClayWorks Posted February 15 Share Posted February 15 I like the self drilling & tapping screws for the thickness of most forges metal. I can't control the wind, all I can do is adjust my sail’s. Semper Paratus Quote Link to comment Share on other sites More sharing options...
Frosty Posted February 15 Share Posted February 15 I'm a huge fan of self drilling/tapping screws, they work a treat on old propane tanks. You MAY need to predrill the holes anyway, propane tanks are NOT mild steel. I have to admit I've welded almost all my propane forges together which is why I have so many, I can't take them apart to modify or change without cutting welds. Sooooo I build another one. <sigh> Except for large work I use my bolt together brick pile forge almost exclusively anymore. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
Mikey98118 Posted February 15 Author Share Posted February 15 The temptation to "just weld it together" bugged me for several years. So, I gave away all my welding machines to friends; no more temptation...at last Okay, that's a lie. There is still some temptation left, but I can just lay down and be very still, until it passes Quote Link to comment Share on other sites More sharing options...
Frosty Posted February 16 Share Posted February 16 On the shop floor next to the pieces of forge? How sweet. My biggest welder is my Hobart 120 Handler wire feed. I fire up my lincoln portable so rarely I usually have to spend $100 or so at the small engine repair guys to get it running. But Boy oh BOY will it make a competent weld on heavy section when I need it. Yeah, I know I could rent a welder when I needed one for less than ONE get it running outlay. <sigh> Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
Mikey98118 Posted February 16 Author Share Posted February 16 Is there anything we can't get addicted too? My last gas weld must be thirty years in the past; I still wanna... Quote Link to comment Share on other sites More sharing options...
Frosty Posted February 16 Share Posted February 16 Probably not, I have a serious thing for wintergreen Altoids and talking to strangers. The trick to not being tempted to gas weld is buy an oxy propane torch. They get plenty hot enough but the velocity of the flame just blows the melt out of puddle. Braze, silver solder, best there is but won't gas weld steel worth spit. Aluminum yes, silicon bronze no sweat but not steel. Sometimes I am very tempted to buy the gear to tig weld, just like gas welding but oh so much better! Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
Mikey98118 Posted February 16 Author Share Posted February 16 I never enjoyed TIG welding. One of the things that was so enjoyable about oxyacetylene welding, was that it was just that little bit slower; slow enough for mirror welding. There is nothing like fixing nasty messes on the hidden side of marine pipes, to mollify a worried boss Quote Link to comment Share on other sites More sharing options...
Frosty Posted February 16 Share Posted February 16 Yeah oxy ac welding is very controllable and . . . is relaxed the right word? What I like about tig is it only heats what I need heated and can be very precise where the oxy ac flame heats quite a bit around it. But they're just the same, make a puddle fill the puddle. Size shape and depth of the puddle is the art of it all. Welding dissimilar thickness was something I really enjoyed, enough challenge to keep me on my toes. Dang it, now I'm missing an oxy acet rig! Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
Another FrankenBurner Posted February 16 Share Posted February 16 I weld metal in all the ways that I can afford and know about. I enjoy each of them for their own reasons. TIG is one of my favorites to do. Mostly for the reasons Frosty stated. It’s clean, and requires skill/practice. You can really get in the zone. The modern welders with all the settings make them very capable and controllable. AC balance/frequency, and pulse frequency/duty cycle along with remote current control (pedal, trigger, roller) have really changed the game. I use MIG a lot too. The hot glue gun for metal. Soldering/brazing also makes the list of fun to do. I like to manipulate metal. Forge it, cast it, machine it, turn it, weld it. I do weld my forges together. Tacks and stitches. No need to full length weld. Easier to rework. If I anticipate the need to access a structure, I design fastened panels in the mix. Not to oppose anything said. If you have the means/skill to build it and works for you when it’s done, it was done the right way. Whatever way that was. That goes for arc welding forgings as well. I don’t consider it cheating. (I too enjoy forge welding) I recently watched a video of a guy talking about never lowering himself to electric welding a forged piece. No real blacksmith ever would. He was using an induction forge. Good for a laugh. Forget about the angle grinder, band saw, drill press, electric lights, automobile to acquire these things, and so on. Real blacksmiths are ok to use those things, but that arc welding, no sir, that is crossing a line. Quote Link to comment Share on other sites More sharing options...
Frosty Posted February 16 Share Posted February 16 Oh yeah, no "real" blacksmith would ever use an arc welder, that old phony Mr. Hobart may have been from a family of blacksmiths going back many generations but when he invented the ark welder to save time and money on failed forge welds he surely stopped being a REAL blacksmith! Samuel Yelling either, he lost his blacksmithyness when he started buying arc welders, actually had 20 on his shop floor and spares ready. Nope, no blacksmith Samuel Yellin! Ahhhh, the myths wanna be smiths and huksters push, makes them pretty easy to have fun with. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
JHCC Posted February 16 Share Posted February 16 13 hours ago, Frosty said: silicon bronze no sweat Oh, really? <strokes chin thoughtfully> Also, don't forget how vigorously Edgar Brandt embraced the artistic possibilities of oxyfuel welding. Quote Link to comment Share on other sites More sharing options...
Frosty Posted February 17 Share Posted February 17 Yes, it welds surprisingly easily and even easier with a light sprinkle of Peterson's #1 blue flux. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.