son_of_bluegrass

I don't know what is available in or around Norway, but here in the US, welding eye protection has to have both IR and UV to meet ANSI specs. I don't recall the specific number associated with the welding glasses but a search should yield results then you can ask for something that meets that spec. As mentioned shade 3 is considered appropriate for forging. ron

So would I. The inventor made an appearance on a woodwork forum I read and I asked about the possibility of getting filters for organic vapors. He said he wasn't interested in developing that. I bought a standard half-mask respirator and shave to use it. ron

I looked in one of these a number of years ago and found they only had filters for nuisance dust, not for vapors. If all you need is nuisance dust filters that's fine. ron

It sounds like you're just starting out. If someone hasn't suggested it yet, check the ABANA (Artist Blacksmith Assn. of N. America) site for an affiliate close to you, attend a meeting and you'll likely find someone willing to show you the basics. ron

I've heard that stirring the water every day or so will discourage mosquitoes from laying eggs. They like still, stagnate water for breeding purposes so it may work. ron

First let me state I've never tried and may not have any idea what I'm talking about. But my first thought may be putting some sort of resist over what you don't want to change. Or maybe, depending on what you're doing, adding the inlay after cold (or hot) bluing? Hopefully someone will come along with experience soon. ron

When you say "small portable forge" I think rivet forge. I've burned both coal and charcoal in such a beast. If you put lining in the pan and control the size of the fire there can be little difference by weight in coal and charcoal. if you haven't lined the pan, or don't keep your fire confined you'll likely find you use more charcoal by weight than coal. But there are a lot a variables in this particular equation so you may find results all over the place in practice. Coal is about 5 to 10 X as dense as charcoal (depending on method of making, species etc), so you expect to use 5 to 10 X the volume of charcoal as coal. ron

Terrible lay-out on the report. Yuck. That aside, I wonder how hammer head hardness, shape and weight affected the results. ron

For stuff inside, not a lot of protection should be needed. Personally I don't like polyurethane, it starts looking mass produced. If it were me I'd do a hot wax or oil finish. ron

I've heard that as well and wonder what in the slack tub relieves poison ivy. I theorize (never had a chance to test) that it has something to do with forging with coal and the impurities of the coal building up in the water rather than just dunking hot iron in the water. Does anyone have any information? (I guess this could hijack the thread - sorry) ron

Research to see if a charcoal kiln would be ok under the burn ban (enclosed fire not open)- if so, build a charcoal kiln, make charcoal, keep forging. Chase skirts (one of my favorite pastimes). Research your next project. Redesign your forge (can you make it better?). ron

I find a sharp straight razor is the best shave I can get, a dull razor is the worst. I shave every 2 or 3 days, otherwise I find the respirator I use when woodworking doesn't seal right. Even when I was in the army, I could get away with every other day with the straight but had to shave daily using a safety. ron

You may find it useful to read a basic metallurgy text (or the relevant parts). I think "Metallurgy Theory and Practice" by Dell Allen (I think that is right) is a good start and can often be found in a used bookstore for a few dollars. If you can find it, "Metallurgy of Steel for Bladesmiths & Others who Heat Treat and Forge Steel" by John D. Verhoeven is available as a free pdf for non-commercial applications. ron

It is my understanding that the lower viscosity of warm oil allows for faster convection which takes heat away faster. I believe there is a point where warming the oil further doesn't add significantly to the speed of cooling. Water is already very thin and doesn't become faster when warmed. Water tends to be such a harsh quenchant that it is sometimes warmed to reduce the speed of cooling with the idea it will also make it less harsh. Interestingly adding salt to the water will speed the quench and supposedly is less harsh than plain water. We all didn't know sometime. ron

Or you could mention it and state it is a legend and may or may not be true. ron

You spoke of not wanting to use gas due to concerns of the school and fire marshall with the fuel. Have you asked about a solid fuel forge running at 3000 F? They may think the propane is safer. I assume you have already started talking to the district and fire marshall and have approval to create a proposal with forge designs, fuel (including storage and acquisition), safety procedures, curriculum and all that? If not you may be putting the cart ahead of the horse with your question. ron

I've heard - never checked into it, so this is second hand info - that in some states it's a felony to own a running iron. Don't know if it's true or not. ron

Grinding the striking surface may have made all the difference in the world. The surface of the steel can lose carbon at forging temperatures, depending on the conditions of the forge. If the spring was recycled it may have different compositions right next to each other. Taking a moment too long getting to piece cool during the quench can make a difference. Quenchant temperature can make a difference. Even though you tried to control the variables, very small variations can make a big difference when heat treating steel. As for grain size, generally smaller is better but I hear that for flint strikers big is good. Supposedly larger grain throws sparks better. ron

As for the $/hour that depends on the cost of fuel, the specifics of the forge, how big of a fire you work in and those sorts of things. With the proper set up you can use about the same weight of charcoal per hour as coal. ron

I have a small forge that I think is similar to yours. When I picked it up it had a cotton belt that was in need of replacing (many years old). I started looking for leather but was unable to find it locally so I put cotton webbing on it with no problems. ron

I beg to differ. On an episode of "Mythbusters" some time ago they did just exactly that. And got a fair shine on it as I recall. ron

I had always heard it was a set number of nails of that size for that many pennies. I think it was 100 nails. So 100 3-penny nails would cost 3 pennies. It came to be associated with the size of the nail and lives on today as such. Pennyweight was originally the weight of a penny in silver and is equal to 1/240 pound troy, if memory serves. ron

I like Frank's suggestion but split both ends and turn one into a handle instead of a leg. ron

As was mentioned, coal, if properly coked before you stick the metal in the fire works fine. The coking process burns most of the impurities out so they aren't a problem. As for the borax, it is generally used when welding as a flux. The flux helps keep oxygen out of the weld area and helps remove the scale that would make it harder to weld. I've read of people using borax as an anti-scaling compound under the idea it keeps oxygen from the surface of the steel. ron

It sounds like there was fresh oil on the hooks. So the oil will need to cure completely before they are no longer sticky. Linseed oil cures on contact with oxygen and before it cures completely it will be sticky. You can speed the process by heating the piece. There is no need to apply the finish to hot work if you aren't going to "burn it on" like you would wax or non-curing oil. On wood, boiled oil is considered cured after 48 hours or so but on metal, it takes longer and may be sticky for weeks. (It has to do with the thickness of the coating as the oil soaks into the wood and thins the layer allowing for faster drying.) Does that clear things up or do you have more questions? ron