Preview - Lesson - Backpacker's bellows

This is one of the upcoming articles being worked on currently:

This article will be on building a small set of "backpacker's bellows" for use with a ground or bucket forge in the wilds, or souping up your bbq grill or fireplace. These little single chamber, dual valved bellows can also be scaled up for other uses including general blacksmithing (though a dual chamber bellows system is much more efficient).

Blacksmith Lessons - The Ground Forge

The Ground Forge

In previous articles, I have mentioned the ground forge, and I figured I should cover it in more detail. The original mention is here: http://ironangelforge.blogspot.com/2009/08/blacksmith-basics-forge.html.

The ground forge is really the beginning of blacksmithing as we know it, and is a hold over from the bronze age that preceded it. In many areas of the world, in the deep mists of the past, bronze and iron workers worked side by side, adapting techniques of the older metal into forming the new iron. That transitional stage is a whole other series of posts that we will cover at a later time.

As mentioned in the first post, some parts of the world continue to use ground forges to this day, though most areas developed taller “table” style forges. For the modern backyard blacksmith, historical re-enactment smith or the like, the later table forges are usually a better choice. But when you need a forge and are away from your shop, or are camping and need to make a quick tool, the ground forge is certainly a usable and very simple solution. For those who are interested in bush craft and being able to pack in to the wild very lightly, the knowledge of how to build a ground forge is an invaluable tool.

All you really need is an air source (covered below), a method of getting that air to the underside of the fire, and ground soft enough to dig a hole in. You can use any handy tool to make your hole, but its best to not use your hands, just in case there is a sharp stone or root in the area you are digging. If you find a root, move your hole. If there is a large root in the ground, it could catch fire and that could lead to an issue you don't want. You will also need forge fuel and tools, along with some stock to work.

Once you have found a suitable location that seems reasonably rock free, clear any ground debris such as leaves and sticks back a few feet and make sure there is nothing flammable over head for at least 15 or more feet.

Dig a narrow trench long enough for your air tube and a round hole about 6-8” in diameter. The trench should be a few inches deeper than your forge hole and angle upward out of the hole. The forge hole should be round bottomed, so it will be between 3 and 5 inches deep, with the dirt removed piled up around the outside at a low angle. Lay your air tube in the trench and cover it, at least at the end nearest the fire pit. The dirt covering is there to protect it from heat and keep it from moving. Pack the dirt tightly. Put in fuel, assemble your air system and light it up. You are done!

In case you don't have a set of backpackers bellows (described in an upcoming article) or another portable air source, there are a number of ways you can get air into your forge in a number of ways. The simplest is to blow into the end of the pipe. This will likely make you light headed before you reach a decent heat. You can also make a funnel shape and fan it with something handy to focus more air into the inlet, and this will work pretty well in a pinch. If there is a decent wind, building your ground forge aiming into the wind with a large funnel to catch and focus it may allow you to work in relative ease, the problem is you can not control the amount of heat. This may or may not work at all, depending on wind and location.

If you don't have a portable inlet pipe, you can build one by simply finding something to cover your inlet trench, then sealing it up with dirt. The more fireproof, the better. Bark will work, but it will eventually burn at the forge bowl and the inlet will cave in. Stones may work, but be ware of this; many stones have some water in them, and under heat may split or break, possibly with some force (another reason to make sure you remove them all from your bowl). If you can scrounge up a bit of metal in the field, such as a steel can stomped flat, it will work better than bark or stones. Just be sure to recycle or throw the can away when you are done. And when done, make sure to fill in the hole and trench as well to prevent breaking your ankle in the middle of the night in camp.

If you are in a clay area, you can “glaze” the inside of the bowl with a bit of water to smooth it and help it keep it's shape. If you are using wood or charcoal, the ash will help to harden the bowl somewhat, so if you use the ground forge for a long while it will get nearly concrete like in a clay bed.

In a ground forge, you will find there will be problems with clinker and slag build up at the air inlet, so you may have to tear down and clean your fire more often than in a cast iron pot table forge.

Now that you know how to build a ground forge, you can adapt this technology to make your own charcoal as well. Simply dig a much bigger ground forge, start the fire at the base near the inlet hole, and bury the top with the removed dirt leaving a small hole at the top for smoke to escape through. You don't want an open, flaming fire, just a slow smoldering one. Make sure if you are going to burn charcoal that you have a lot of time open; it will take a while. You can burn dry wood to make charcoal, but wet wood can also be used if you have nothing else at hand. It may not burn as easily or as well, and may even go out, so keep an eye on the smoke coming out the top. You may have to dig it out and relight it a few times with some dry kindling. We may put up a more extensive article on forging with charcoal in the future, and if we do it will have a much more extensive article on making your own charcoal with it.

In an extreme pinch, you can forge with just a wood fire. It will not be as hot as a coal or charcoal fire, and will pop and spit a lot more, so watch out for flying sparks. In a ground forge intended for use with only wood, you may have to dig your pit larger. The easiest way to do this is to dig a long trench with the air inlet coming in at a 90 degree angle. Lay your sections of wood in the trench and push them forward into the fire area as it burns away. You may have to wet it from time to time to keep the fire from spreading up into your fuel reserve. Be careful not to get your main fire area wet, and watch out for bursts of steam from the fire and from the inlet when you water it. Hot steam can blast out several feet, so be careful.

That about covers the ground forge for now. Keep on hammering.

Blacksmith Lessons – The Side Draft Forge Hood, part 2

Part one is here.

In our last lesson we covered laying out your pattern in cardboard. Now it is time to start building the real deal. The hood can be built from any spare sheet steel you have about, ranging from 16 gauge up to 1/4” thick plate stock. The thicker the material, the heavier it will be and the more difficult it will be to install and move your forge after it is in place, so keep that in mind. Ours is made of 1/8” plate from the scrap yard and cost us about 50 dollars US when we built it. All the steel does not need to be the same thickness either; if you have a mix of thicknesses, you can still build the hood.

If using mixed weight steels, your front, top and back take the most heat and strain, so you may want to use thicker stock for those. The base takes the least stress, so you can use lighter steel here. As the box heats up, the back wall may flex and make a heck of a bang, throwing dust and ash about and surprising you. Thicker steel or reinforcements (covered later) will help to prevent this.

Once you have your steel, take your cardboard patterns and either a marker or chalk and lay out all your parts. If needed, you can join two or more smaller pieces to make a section large enough for your use. If you do have to join plates, make sure the joint is airtight with either close set rivets, or a weld. Be aware, a single long, straight weld is likely going to warp the steel, so you will have to weld a few inches, move to another section of the joint and weld there and so on until the entire joint is welded to reduce warping. Rivets look great (very steampunk!) but a weld is easier to get airtight.

Once your pieces are laid out, cut them to shape using either a cutting torch or plasma cutter, or if in thinner steel some kind of metal cutting shear. Thinner steel will be harder to weld and may require some unusual modifications to the techniques given here to work. If needed, clean up your cuts a bit with an angle grinder or file, but be careful to not cut too much metal away. Having extra metal is far better than too little, as you can always grind or file away, but adding a bit is more tricky.

These instructions assume you are welding all the parts together. You can, however, use sections of thin 16g steel cut into long, 3 to 4 inch wide strips, folded to 90 degrees lengthwise and a LOT of rivets to rivet the entire hood together. Pop rivets are not as strong as hammer set rivets or roofing nails clipped short (which make workable make shift rivets and are less expensive by far). And this has not been tested with pop rivets either, it may well not work!

With your pieces cut out, you are ready to begin assembly. Start with the base plate and the back plate. Lay the base plate flat on a welding table or concrete, and place the back plate in place. It will need to be braced to keep the joint at 90 degrees the entire length. Tack it in a few spots on the inside and outside with 1” long tack welds. We welded ours entirely from the inside along the lower joints, you may as well, or turn the assembly over and weld from the outside. The inside welds allow the box to sit flatter on the forge table however.

With this weld complete, check the joint for square, and adjust if needed, then weld in one side piece. Again tack in a number of places before welding to help reduce any warping or shifting. You may want to tack the other side in place as well and test fit your front piece just to be sure everything fits. It will be easier to correct a problem now, with everything just tacked, than once it is welded in firmly.

Our hood has a section of light weight angle iron along each upright corner to make it look better, and add some strength to the structure. It is welded in place from the inside, tacking it in through a couple holes drilled at an angle through the corner joints. Once our corner covers were tacked in place, each corner was welded from the inside full length in one pass with enough heat to penetrate somewhat into the angle iron. You do not need to be this aggressive about it, as long as the joint is airtight. It can also be “skip welded”. That means you can weld a section, move to another and come back once the first weld has cooled, so long as the joint is clean and solid.

Next we suggest adding the extension to the face of the front. We welded this on from the inside as it looks better. With that in place, we welded the front on. Here is where it begins to get tricky, as you will have to lay the tacked assembly on its face and nearly climb into it to weld the bottom joint and the lower part of each upright joint. And you may have to support the front with bricks and connect your arc welder clamp directly to the assembly to keep the whole from rocking with the front shroud already in place.

Once you have the lower assembly together, you may want to weld in a pair of bars from the front to back plates to keep the walls from flexing. Angle iron works well here, with one section mounted on each side of the top of the intake opening. Putting a single bar across above the opening is not as effective, and heat will probably cause it to flex over time. These support struts are not critical, and are completely optional.

If you have decided to put in the angle plate that directs smoke upward, put it in and tack it in now. It does not need to be fully welded into place. Just make sure the front edge at the inlet is welded flush with the bottom so there is no gap.

Now that the lower assembly is complete, the upper half will now be assembled. This will be a little tricky, but not horrible.

First, tack the collar and check to make sure your pipe will flex and fit over it tightly. Then weld the collar into place and tack the top plate at 90 degrees to the back plate. Make sure the collar is on the outside! This plate will make lining up the rest of the plates a lot easier. Lay the assembly on its back, and fit and tack the front upper into place, then each upper side. If they are curved, you may have some fun trying to match the curves so the joint it tight and easy to weld. A heavy pipe in a heavy vice is one way to allow you to form the curve; just hold the steel over it and strike beyond the pipe with a wooden or rubber hammer. You can also put it across two bricks and stand on it, or if all else fails, drive over it with a car. Be creative but safe!

With all the parts tacked in place, weld all the uppers from the outside. There are some long welds here, so take your time and do a good job, as these will show. Once you are done with the welds, you can take an angle grinder and smooth your welds if needed.

Your side draft hood is now done! Now you (and probably a friend) will have to move it into place on your forge bed. Watch out for pinched fingers! If you like, the hood can be raised a bit with a layer of brick, and this can aid in creating a better draw, but is not critical.

Once the hood is in place, mount your riser pipe up to your stack (or straight up through a collar in your roof if in a shed or the like) making sure all is firesafe and sealed (another much larger topic!!). With that, your hood is ready to use.

We will cover making the “flip up hat” part in the next post, though you may want to make it and mount it before you install your hood. It allows you to suck up much more smoke when you first light the forge.

A few notes on using the side draft hood-

Before lighting the forge, put a ball of paper in the intake of the hood and light it to pre-warm the air and start the draft.

With the forge first lit, when the most smoke pours out, you may need to place a thick plate of steel on the forge angled up to the intake hole on the hood to get the hood warmer and suck up most of the smoke.

Once the hood is warm, the draft will be more effective. As soot and ash seal any tiny holes in your stack and hood, it will draft better. The more airtight the hood and riser pipe are, the better the draft. In fact, the draft can get quite strong. In the right situations, ours will suck up a piece of paper left on the forge table (much to our surprise). The trad off here is it will also suck any heat out of the room. You may need to make a cover for the intake for times you are not using the forge to prevent it from drawing all the heat out of your shop in the winter.

Once the hood is drawing well, you may notice the flame rising above the forge bending at a steep angle into the hood! Just because the heat is not rising directly does not mean the infrared coming from the forge is not... if your ceiling beams are low and wood, you may need some kind of heat shield still.

The forge hood will get warm in use, and in heavy use it will get hot. Be careful about brushing against it, as it can burn you. Also make sure it is well away from walls and nothing flammable is leaning on it.

A larger intake opening will still draft, though not as well. If you only have an 8” exit stack, you can still have a 12” by 14” intake with a tall chimney and good connector pipe. It will not draw as effectively, but it will still draw.

On some days, when the atmosphere is right and the hood is warm enough, you may hear a faint rumbling as air is drawn into the opening. This is normal and not a problem. If it is quite loud, something is amiss or something else in the shop is causing it. The large, flat walls of the hood may be resonating in sympathy with something else in the room. Try sticking a large magnet to the side, off center, and see if that stops the sound.

That about covers it for now, images and part three coming soon!

Quick and easy solar heater

This post is pretty far off from the normal line of this blog, as it discusses something made with very little metal in it. Many years ago, my step brother built a set of solar collectors for our high school wood shop that were still in use 20 years later. They were entirely passive and built from simple pine 1x4 and a sheet of left over paneling. These simple collectors cut the heating costs by about a quarter over the colder months, which is pretty impressive! There were fans in the shop to push the heat down, but they were part of the existing heating system.

In this day and age, any free heat is a good thing, and these may help keep your forge or garage a little warmer in the winter. With some adaption, they might even be able to help heat your living space as well at the cost of loosing light coming in the windows they sit in.

Essentially, all these systems are is a large, shallow wooden box, with a labyrinth of wood inside to make the air travel a longer path through them. The entire interior is painted flat black to absorb as much infrared heat from the sun as possible. As the inside of the box warms, the air will begin to rise through it, creating draft at the inlet hole which will draw cooler air into the box, where it warms and rises continuing the cycle. The only real problem is the heat will come out the upper vent in the box and rise to heat the ceiling of your work space, so some kind of ceiling fan or other air circulation unit will be needed (and we will cover a clever one as well in another post).

Measure your south facing windows, and subtract 1/2” from that measurement for the outer dimensions of your box. Keep in mind that these boxes completely block most of the light coming in, so you may want to only cover a few windows, depending on how your shop is lit.

The outer frame is made of 1x3 or 1x4 pine with the uprights cut the the length you came up with above, and the cross members cut 1 1/2” shorter than your measurement to account for the thickness of the side rails. This box is assembled with glue and screws, making sure it is square at the corners. Measure and cut your back panel and glue and screw it onto the box. With that done, cut several 1 by sections about 90% as long as your side to side measurement. These will make up your labyrinth slats.

Lay these out on the inside face of your unit, mark the positions and drill small pilot holes for the screws that will mount them. In our illustrations, the holes are large round openings, and either this shape or rectangular holes will work effectively. If you want to use rectangular holes, drill four holes in a rectangle at the top and bottom of the back corners as shown in the illustrations to cut out the intake and exit holes. The exit hole should be a bit bigger than the intake hole, perhaps as much as 50% bigger.

Once the labyrinth cross bars are in place, the entire inside should be painted with flat black paint and allowed to dry. It may take a couple coats of paint to get an even, complete coating. You may want to paint the back of the unit white to reflect any ambient light in the room back to help make up for the lack of light your covered window will have.

The purpose of the labyrinth is to make the path from the intake to exit longer. The cross laths can be mounted flat or slightly inclined upward. Both work, but in theory the slight inclines should cause the air to move through the box a bit more easily.

Once the paint is dry, place them in the windows they are made for, and secure them so the box doesn't suddenly fall out. The glass in the window frame acts as the front of the box, and a bit of foam weather stripping around the outer edge of the box should help seal the box into the window frame, hopefully incresing your amount of heat output.

That's all there is to it! These systems may not produce a lot of heat, but any free heat is still free heat. In closing, be aware that some glass restricts infrared more than others. The more infrared that gets into your collector, the more heat it will put out. These systems can be adapted for stand alone use, but that is a whole other topic. Have fun, be safe, stay warm!

Blacksmith Lessons – The Side Draft Forge Hood, part 1

In previous lessons, we covered building a few different forge beds, and more are coming soon. This lesson will help in getting the smoke and heat from your forge moved to some other place, preferably outside.

There are many types of forge hoods, including some positive pressure down draft hoods that we may cover in another lesson (uncommon, but used in some welding booths and chemistry work). This lesson is on building the side draft style forge hood we use in the shop. This project will require some fairly large sheets of steel, a fair bit of layout work and the ability to cut said steel using either a shear, saw or torch/plasma cutter. You may have to see if a friend has some of the gear needed for this build if you want to follow the plans below closely and do not have the equipment. It is intended to be electrically welded, but there are other ways to make this hood without a welder, which we will cover.

To create a pattern, we suggest cardboard boxes to build a mock up first, then use these pieces as pattern parts to layout and cut your steel with. You will need several large cardboard boxes, opened up, and tape to assemble the pieces. Of course, some method of cutting the cardboard will be needed as well.

The version of the hood we use also has a flip up “smoke hood” for the rush of heavy smoke when first starting the forge. You do not need to make this on yours, but it is quite helpful. Do not make it solidly mounted, however. It will get in your way more often than you would like to imagine.

We purposefully left out dimensions on the side draft forge hood drawings; you need to build this hood to stand on the table you have, so you will need to create a pattern based on your own system and measurements.

To start with, you will need to layout your base. The edge of the base should be very near the edge of your forge bowl. Ours is 1 1/2” from the top of the bowl, and sits against the projecting flange of the bowl. At first this may seem strange, but it needs to be close to make the draft effective. Cut a piece of cardboard that will lay on your forge table next to your firepot. Of course, make sure the forge table isn't still hot or the forge lit! Make this bottom plate as large as feasible, ours is 32” wide by 24” deep. This will allow a large expansion chamber inside the side draft and will help your smoke draw more effectively.

The next part to design is the back of the unit, which should be about twice as tall as the chamber is wide, or a bit more. In ours, and in the illustrations here, the side walls are straight for about as long as the box is wide, then have a sweeping taper to help the rising smoke gain velocity as it enters the flue pipe above. This is not critical, but it does look more graceful than flat angled upper sections. With the back made, tape that section to your base plate.

Next up come the two sides. Use measurements from the bottom and back to lay out two sheets of cardboard, cut and tape in place. Then comes the front.

Of note here; the opening in the front should not have as much volume as your riser stack pipe does. The larger the opening, the less draft the stack will have. If you have an 8” diameter stack, your front opening should be around 50 square inches or less. So an opening that is 10” by 6” may work, while an 8” x 6” opening will draw better. The problem here is that your fire pot will be larger than your intake in this case and some smoke will escape into the room. If at all possible, use 12” pipe since you get about a 112 square inch opening to work with. That is a nice 10” by 11” intake area, and is roughly what ours is. Once the hood warms and the stack begins to effectively draw, we have very little smoke in the room.

We made our opening with an arched, rounded top in the cut, which was outlined with the smoke lip (more on that in a bit). It is set to be centered with the forge inlet, so if your bowl is not right in the middle of your forge table (front to back) you may have to adjust where your opening is. Tape this in place with the other cardboard pattern pieces.

Now you will have to make the front upper part. This is the most complex part of the side draft forge. It is very similar to the upper part of the back pattern piece, but since it leans back, it is slightly elongated. There is a lazy way to do this however. Cut your two side uppers, with a long angle cut on one edge of each along the length. The upper edge should be the diameter of your inlet pipe, while the bottom edge will be the length of your side pieces. If you cut your back piece with sweeping uppers, you will need to measure how long the curved surface is using a piece of string or a flexible tape measure to get the length of your uppers. With these pieces cut and taped into place you can lay your uncut front upper against them, reach inside and trace the correct shape onto the cardboard then cut it to shape and tape it in place.

All that is left of the basic box is the top plate. Take the measurements from the uppers, and cut a piece. We will make a mount for your flue pipe that is slightly oval, as it will be easier to mount firmly and will make the stack draw better. Cut a strip of cardboard about 2” wide that is as long as the inside of your flue stack (use string or a flexible tape to measure this). Tape it end to end to make a circle, then squash it a little bit to make an oval, and put it on the top plate to draw the cut out hole. Cut the hole, then tape the collar in place.

The main body of your pattern is done! There are a couple more pieces to make though. A few more small strips are used to outline the front of your intake opening, and this is not needed but does give the hood more strength and makes it look better. It also increases the draft, since the opening is now extended closer to the forge fire. We also added an angled plate internally to help funnel the smoke up the expansion chamber and increase the draft. This is a piece as wide as your base, and several inches longer than it is deep (ie, in our, the base is 24” by 32”, so our plate is 32” square, and made of lighter steel than the main body of the hood). This is not a critical part however.

Now your pattern is complete! In our next installment we will cover the actual construction and discuss theory further.

(note, pictures are still in the works - they should be up soon)

Coming soon

The studio is in order, everything is set up and preliminary tests sound like the quality will be just a bit better than before. As usual, we are dumping the MXL SP-1 mic into a peavy board, into the sound card then into Reaper for recording. There may be a post on this in the near future, for those interested in pod-casting and the like. Our gear is pretty old school, but we may add some info on simpler set ups that some of our associates use.

In forge news, we (being Nic and myself) have done some fun new Damascus lately, and pics will be forth coming along with a bit of writing on that. Other projects are being photographed, and lessons on making some of those will appear here eventually. As long time readers know, it can be a fair amount of time between posts, depending on show and life schedules. Now that it is getting colder, posting will be more common. A few future articles will include some non-metal based projects including a solar heater for the shop that you can easily adapt to your work space (now up here, quick boxes for storing items (such as hammers and tongs) and more lessons.

Life has thrown a few curves, so how much gets posted will depend some on that. I hope all of you are having a great fall, get out and enjoy the colors and the crisp air.

Until then, stay tuned, keep the fires burning!

Is it Octoburrrrr already?

The summer past every too quickly, and now as the air begins to chill we will have more time to post and work on lessons. There are new drawings on the way for the bellows projects, as we noticed a lot of people are looking at that information. Also in the works are a whole new string of lessons, now in a slightly modified studio format (the sound quality will change slightly, whether it is for the better or worse is still to be determined).

Stay warm, keep your fires lit!

A hard time of it

Just a quick post.

I'm having a hard time of it right now, lots are in the works at least. It was many years ago today my grandmother went to be with my grandfather beyond this world. It has now been nearly half my life without her guidance, and more without his and I dearly miss them both.

The house I grew up in through my teenage years burned last week, my bedroom there suffering the most damage (as in it's completely gone) and Ive been thinking of that past a lot. It was both a happy and severely unhappy time, but knowing my little place in the history of the Reek Mansion is now gone does make me sad. All the quartersawn oak trim I knew so well is no more. Granted, I have not lived there in half my life, but it does sadden to know it is no more.

It is not just my day either; one friend had his car stolen today, another had a near miss with a tornado in Tennessee. It seems the last day of February is being rough on many.

So good readers, take this away from here: Enjoy those around you and your environment, live life to its fullest. There will be some actual blacksmith posts in the near future.

Snow and fire

Hello all!

Now that we are on the other side of "Snowmageddon 2011", let's talk a little about fire and snow. Ok, this will cover a bit more than that, but its an easy title.

In the past, I have done a number of demonstrations outdoors in winter weather and for a time I even worked outdoors without a proper building. This educated me on a number of interesting things I have not seen addressed in many other posts on blacksmithing online, and have not heard a lot of guys talk about at hammer-ins or around the table.

Let's start with working outdoors in snow. Visually, this can be very spectacular; thick falling snow, lit by the dancing light of a forge, a trailing flame-like ghost flame of mixed heat and steam from the snow touching hot steel... Ah! Male Romance right there my friends! But there are a few safety and technique considerations to be aware of beyond the obvious ones. First is footing; falling on slick snow or ice holding a hammer and hot bar of steel is not fun. And working on ice is even more dangerous since even if the hot bar does not hit you, it can hit ice and burn you with a jet of steam. Make sure your boots have good tread, and clear your work area as well as you are able. A thin layer of kitty litter may be in order to increase traction, or lay down a clean, dry sheet of plywood to stand on. Dropping hot steel on plywood will cause a scorch, but it will not catch fire and burn unless the steel is left on the board for a longer lenght of time, and you can grab snow and put out the fire easily.

The second consideration is frostbite. Even though you are standing next to a fire, you are outdoors in less than freezing temperatures. And you are sweating more than likely, and this can add to the possibility of frostbite. Make sure you are wearing proper, safe, warm clothing. A nylon snowmobile suit is far, far more dangerous than a pair of jeans over cotton long johns and two layers of socks. Once you have layers, your body will be more able to keep itself warm and the extra layers of natural fibers will also help to wick away sweat, keeping you safer from frostbite. If you start having numbness though, get inside and get warm! Winter is one of the few times I wear cotton jersey gloves to forge in, and I make a point of wearing a wool hat under my hearing protection.

The third consideration is less obvious; if you get your anvil wet, laying a hot bar of steel on it and strikign it with a hammer will cause a small steam explosion. This will crack like a gunshot (bad for your hearing) and throw some small amount of hot scale and steam which can burn you. Falling snow, wet gloves and other things are possible ways for your anvil to get wet. You can wipe it off, but it will take a lot of wiping. The other option is to hover the hot bar just over the anvil for a few seconds, letting the radiant heat from the bar drive the moisture away from where you are about to lay the bar. A quarter inch or so above the anvil works well, and keeps the cold anvil from rapidly pulling heat out of the bar which will happen if you lay the bar on the anvil to let it dry it.

Next we get the the heart of the title. Your forge won't like the snow. If you are running a basic coal forge, once it is lit it will keep the snow off the top of your banked fire without a problem. Unless the snow off your garage roof falls onto it, that would be bad... and you shouldn't have your forge set up that close to a building anyway! Safety first, remember! The big issue here is actually the melting water from your forge keeping itself clean of snow. This water will seek out the lowest point it can find, and that is often down in the firebowl where it will turn to steam and jet out. It could also crack a cast iron firebowl if enough water is present to suddenly change the temperature of the hot iron. If possible, keep a sheet of steel over the forge either suspended from above or on bricks to keep the snow off the top of the forge. Leave enough room above it for the heat to rise and dissipate and be careful of placing anything that could burn on top of the protective roof. A slight angle will help the steel shed water away from your forge as well, so if you can try to get it tilted and safely in place.

Another consideration to deal with is in winter the air is both heavier and colder. You are pushing this colder, heavier air into your hot forge fire. This will cause it to take just a bit longer to get to a given temperature, and if the air is wet may prevent you from being able to reach welding temps. The nice thing is the heavier air is easier for your bellows or blower to push, so depending on your system, you may not notice a huge difference. Test it with non critical projects however, just in case it comes to heat faster than you expect. Loosing a chunk of 3/8" round stock is much less frustrating than burning a five thousand layer Damascus billet.

If you are using a gas forge, there are some other special considerations. The refractory that most gas forges are cast from is much more sensitive to being wet than cast iron, so you should make every effort to prevent snow from touching the liner of the forge. Moisture can crack or spall the liner easily, depending on the type and condition of your liner. Atmospheric forges may also have problems with the colder, wetter air, and your propane tank will freeze much sooner than it does in summer. If possible, place a clamp light or other lightbulb near your tank to help keep it warm and your gas flowing. Never put your gas tank on a burner, cajun cooker or hotplate, or put a space heater directly on or aimed at your tank! All of these can end in serious trouble. If you can, a thermal bath will help to keep your tank from freezing. We use a large tub filled with heavily salted water to absorb the cold from the tank, but this bath must be kept from freezing. The expanding ice can damage a tank and make it leak. When I was working outside all the time, the thermal bath got hauled back into the mud room of the house when I wasn't working to keep it from freezing (which isn't going to be popular with a spouse, by the way). A better system may be to build a large insulated wooden box with a couple 40 watt light bulbs inside it, not touching the tank, to keep your gas from freezing quickly. Be very careful here! You will want some vent holes around the bottom, just in case you do have a slow leak in your regulator along with a door on the side facing away from you that opens easily. Keep your fire extinguisher close at hand, even with snow on hand!

Oh and of course, this is information for educational use only, you are on your own and take all responsibility if you choose to use any or all of this information. Study up on everything, ask your local propane dealer if they see any problems with your idea before hand and follow their advice.

That about covers snow and fire for now, be safe, stay warm and keep swinging that hammer.

Airsoft Claymore prototypes are done!

One of the side projects that has been on the back burner for a bit is a "claymore" mine for airsoft. This is a mechanical device that throws a handful of plastic bbs (or navy beans, or what have you) when the trip wire is pulled. They are quite safe, and not really dangerous, but instead are intended to safely simulate the effect of a trip mine in a paint ball or airsoft game.

As we play airsoft, and are fairly handy, we decided that we needed to come up with a few clever versions for our own use, and figured "heck, why not make them available to the community at large!". Yep, pretty soon we will have airsoft claymores on the main site!

These will range in size from a cigarette pack up to about the size of a small footlocker, and will all be custom made and painted. More info on these soon! Right now we are testing the prototypes and we will post a bunch of pics once we have the production run started.

Protective gear for blacksmithing.

I know a few of you out there reading may have asked yourselves “should I wear this near fire?”. Well, this post will help you decided that. Lets start at the top (of your body) and go from there.

Your brain is the most important safety tool you have. It will often warn you something bad is about to happen (like in that question above) and it can be easily upgraded (by educating yourselves on what not to do). Use it first and always! That also means no playing in fire if your brain isn't fully functioning. Be it drink, cold medicine, a lack of sleep or just feeling off, if you aren't on your game, save forge work for another time.

Eye-wear is the single most essential safety item. Period. Why? Simple, a blind blacksmith doesn't know how hot his steel is, where to hit or if he is done. So much of the craft is visual, and most education to further your craft is visual. Good quality safety glasses, furnace glasses or some kind of impact rated goggle is a bare minimum. And they don't work on top of your head – WEAR THEM.

Hearing protection is a pretty close second. Hearing damage occurs over time, and by the time you finally realize there is a problem, it is way too late. And I can tell you first hand, it sucks. Ear plugs, shooting cans or a combination work well and aren't that hard to get used to. Sure, you might not look all that cool, but damn! You have hot metal and a hammer in your hands! That offsets any non cool look right there.

The constant ringing of the anvil, sharp noises from steel being dropped and other sounds can quickly damage hearing, but other sounds over time can as well. Things like a grinder, sander or even the blower can, over time, damage your hearing. Wear cans or plugs.

Next up is your torso. Sure, working bare chested is pretty cool, but a burned nipple will definitely screw up your day. And not just hot steel burns your skin. The infrared heat coming off the forge or a large, hot bar of steel can also cause surface burns pretty easily. If you will be doing any arc welding, these also can cause surface burns. Wear either a leather apron, or a heavy shirt made from natural fibers.

Here is a big thing on clothing to remember; natural fibers ONLY. No polyester, rayon or other synthetics, as these will turn to dripping napalm if they do catch fire. Natural fibers will not melt to your skin, and extinguish fairly easily or on their own (good quality wool in particular). Cotton and linen are also good choices, and many commonly available garments are 100 percent cotton (things like denim jeans for example). Also remember, you are going to sweat. Natural fibers will wick sweat away from your skin to help cool you. Thicker clothing will insulate some heat away from you as much as it holds your heat in.

On your legs, jeans are a good way to go, see notes above on natural fibers though.

On your hands... here is where it gets interesting. We generally don't wear gloves for forging or grinding, but do for welding. Gloves can get caught in rotating machines (that's bad by the way) and may allow things you are holding to slip. Often, you get a lot of physical feedback up through a set of tongs that can warn you a hot piece of steel is about to go on its own way that gloves will prevent you from feeling. Gloves can also give you a false sense of security, and if they get hot can be hard to get off in a hurry. That said, a lot of guys do wear tight fitting gloves with great success.

Gloves are one you are going to have to decide on for yourselves.

Boots or shoes; here is one we see a lot. People forging in tennis shoes. Uh... no. We prefer leather engineer boots, as they protect the feet from falling hot scale, bounced off bits of hot metal and other minor hazards, as well as supporting the ankle. Boots or shoes made of synthetics are just asking for trouble. Remember that bit about molten, burning plastic sticking to your arms and torso? It hurts more on your ankles and arch of your foot. Wear sturdy leather here, K? And steel toes are up to you. We usually aren't moving large, heavy objects, so the worse thing that falls on our feet is a dropped hammer or tongs. Sure steel toes would prevent some loud, bad words. But you get quick about moving when hammers fall.

So that covers the basics of what to wear when forging. We might do some more detailed posts later, who knows?

Have fun, be safe. Wear your safety gear!

Bellows update

I posted a bit on building bellows a while back, and had planned to get photos up of the build process.  Well, that tanked.  Something went awry and I seem to have lost all the photos, so I am in the process of trying to make a few drawings up to better explain the process, then when we build another set I will photograph the process and reshoot (hopefully we will also do video at the same time for our upcoming DVDs).  So, keep an eye open here for new bellows images - hopefully soon!

(see the orginal post here:  Bellows)
Until then, these pics will probably help:

In this pic, we see all three boards hanging in space, one over the other. This is how the bellows would be arranged if the nozzle (with hinges) and lung were mounted, and both chambers were fully open (ie, full of air). The valve boards are shown in violet (without their leather hinges in place), the top and bottom are shown as edge joined boards and the center as chip board. This is only done to make the image easier to understand, please see the main post on what to make these parts from.

This image shows the rough shape and proportions of the boards from the top. Yours does not have to be exact, roughly this shape and these ratios will work just fine.

This image shows the midboard, with the notch at the front for the nozzle to be mounted in, the hanging pins and the holes for the valves. The bottom board has the same valve holes, but does not have the hanging pins or notch at the front.

The top board is the same size and has no holes.

The lung of the bellows will wrap from the front (narrow) edge all the way around the curved rear of the bellows to the opposite front edge.

I will see about getting the nozzle image up asap.

Bad math steel weight estimation

Ok, here is a quick n dirty system we use at the steel yard to estimate the weight on a given bar of steel (this works for hot or cold roll as well as carbon steels). Since we often buy by the pound, not per piece, knowing about how much you have in the truck before you hit the scale helps to keep the sticker shock down to a minimum at check out. This system is really for getting random steel for playing with or so you have various stock on hand for what ever comes up, not for a given detailed project.

For those who have not purchased steel (or coal) in large quantity, I should explain quickly; You weigh your vehicle before you go get what you want, load it up and weigh it again on the way out and pay for the difference. Yes, you could fill your back seat with sand and pour it out before you load up to get more “free” stuff, but be advised if you get caught (and you will) its a whole lot of jail time.

Most steel weighs 489 pounds per cubic foot. All you have to figure out is what part of a cubic foot your bar weighs, right? Heck no! I am way to lazy for that. So some math later, we find that a cubic inch of steel weighs .28 pounds. This is a lot handier... round up just to make the numbers easier; a cubic inch guesstimated weight is .3 pounds. Therefore every 4” section of 1/2” square is .3 pounds, so 3 of those equals just under a pound. Remember, round up. Hey, if you are 20 pounds under at the scale, that's less you have to pay on the way out the door!

So 1 foot of 1/2” square weighs a pound. Ok, a “bad math pound”.

Therefore, if you have a 1” x 1/2” x 1 foot bar, it's going to weigh 2 pounds (since there is twice as much steel there) and a 1” square bar 1 foot long should weigh under 4 pounds. (It's actually more like 3.4 pounds per foot, but round up for bad math.)

you could round down to a quarter pound per cubic inch, but I would rather not accidentally overload the truck and break an axle or some dang thing, not to mention I often hit the steel yard with a given amount of money on hand and I want to be sure I come in under budget for random steel. On a given project, I tend to buy what I need plus 10% for screw ups, but this system is for random stuff to make what ever out of.

Buying thick plate is similar. A 12” by 12” section of 1/4” plate weighs almost exactly 10 pounds, so if you can do some quick math based on this you can guesstimate the weight of a given section of plate. 1/8” thick is half as heavy, 1/2” plate is twice as heavy. Simple! Ok, simplish. You may be able to envision the bar you are looking at as a section of plate, cut into strips and laid end to end to make up a bar or vice versa. It all depends on how you happen to think about volumetric objects, as different peoples brains work in different ways.

Ok, so that works for square or rectangular stock, what about rounds? Since a circle fills about 80% of the volume of a square that is the same width, you can take your formula above to figure out what a square bar that dia/across would weigh, then multiply that by .8 or just call it close enough and have a little money left over at the check out to go grab lunch. Again, this is already rounded up a bit, so your actual weight will be under the guesstimate.

Most other shapes can be though of as made up of parts that you can already easily figure out with the above formula. Angle iron is two sections of flat bar stuck together down one edge, channel is three sections. You can think of pipe as a flat bar that has been rolled into a tube, so here take the thickness then wrap the tape measure around the pipe to figure out what a given section of pipe would be as flat stock (unless you can do circumference of a circle in your head easily – some people can, some can't).

And there you have it, a lazy, bad math way to guesstimate the weight of a given bar of steel!

Or just write down 1/2” square is a pound a foot and 1/4” plate is 10 pounds per square foot and work off that.

Either way.

New Look

Hello all, just a quick post to let you know we aren't dead and we updated the look of the blog here.

A lot of changes in the home life since the last post... I won't go into details, but suffice to say it has kept us busy!  Some new posts are in the works; updating and completing some of the previous stuff (like the bellows pages) and a number of new projects as well.  Hopefully, we will get these up in the next few days.

Until then, stay warm!