one_rod

Ian, I was sort of hoping that if I made the knot tight enough it would hold itself together. But it didn't. I have gas welded and TIG welded copper. I have even stick welded it (an obsolete process in copper nowadays). I was about to agree with you about forge welding the stuff, but as Johnny99 says, the mokume process is a kind of forge weld. Well it's a kind of weld, and it can be done in the forge..... one_rod.

Had to weld a piece of high-carbon steel in for the cutting edge. one_rod.

A friend of mine was suffering from mild arthritis in his elbows. Many people believe that wearing a copper bracelet helps with this condition. Now, he's very big bloke and thought that the ones that were available in the shops were a bit "dainty looking" for his taste. So I made him this. Forged from 6mm copper bar, with 1mm wire wrapping on the ends. I did hope that it would have held itself together, but I ended up having to put a couple of small spots of braze on the back of the knot, and on the ends of the wire wrap. They are not visible once its being worn. one_rod.

Without wanting to step into the middle of the "should I/shouldn't I" debate: I work at a metal treatment plant where we put zinc coatings onto metal. The process sometimes goes wrong and we have to take it back off again. So, a few practical tips for anyone wanting to strip zinc safely. Some of this information has already been mentioned in this thread, but it stands repeating. 1. Use Hydrochloric Acid. Use it fairly dilute and at room temperature. Don't use strong acid, don't heat it up. 2. Never, ever attempt to burn off zinc coatings. 3. Many zinc plated items have a laquer or varnish applied to keep the finish shiny. This will slow down or stop the acid from working. A rub with a wire brush or coarse sandpaper will break it up enough to let the acid work. 4. Work outdoors or with good ventilation. Hydrogen gas is generated, it's inflamable, explosive and besides, the whole process stinks! 5. To tell if all the zinc has gone, wipe the metal with a weak solution of Copper Sulphate on a rag. Bare steel will instantly turn reddish brown or black, remaining coated areas will not. 6. Be very carefull with pipes and tubular items. The process generates a lot of gas and this will find it's way out of the open end of tubes, taking the acid with it. I have seen foaming "acid fountains" six feet high from the end of galvanized pipes in stripping tanks. Not fun. 7. The spent residues from the process (mostly Zinc Chloride) do make exellent brazing flux. But because of the dissolved toxic metal content it would be illegal in most countries to empty it into public sewers. So don't get caught. one_rod.

I have made a few of these over the years, usually from whatever bits are laying around the shop. They do work very well, but are most use if you are welding inside confined spaces, like tanks or containers. If you want plans to make your own, there are plenty about. Here's a good one. http://www.oldwelder.com/venturi.html There is a lot less than $400 in materials here. For bench-top welding nothing beats a proper LEV type fume extractor, with the exhaust air either filtered and returned or vented out of the shop. one_rod.

Ladysmith's thread about inlaying reminded me of something. I didn't want to hijack her thread with it, as it's not really relevant to what she was asking, but I wondered if it might be of interest to someone anyway. As part of my job I have to make fairly large copper forgings, typically from 4" x 1/2" bar. Not very pretty things, but designed to carry thousands of amps of DC current into massive steel components for electro-plating. These forgings have to marked, for the particular component they should be used for. The corrosive chemicals would strip off any kind of paint or ink marking, and the mechanical handling equipment soon rubs off etched or engraved markings. However, because copper is so soft standard engineers letter punches will make a deep impression. Filled with silver-solder, and the surplus metal linished off flat it leaves an indelible, and and very resilient, mark in the copper. No photos of the work stuff. But I do have this, very bad, pic of a copper bracelet that I marked using the same process. I will get to explore the decorative possibilities one day, when I get the time.... one_rod.

I forge with good quality processed coke and, like you, never get any clinker at all. In the days when you were allowed to burn coal in this country I used to get quite a bit of it. The poor-grade anthricite that I use for heating the house produces a lot of clinker, but once it's cool it simply gets crushed up and goes out through the mechanical de-ashing system on the boiler. So yes, a lot seems to depend on the fuel being burned. With a bit of experience it's not that hard to spot clinker forming in the forge. It always forms in the same place, and shoving a cold steel poker through it will make it stick and pull out like so much toffee. one_rod.

One thing to beware of with motorcycle chain. The modern stuff has nitrile rubber O-rings built into each link, to keep road muck out of the rollers. It's impossible to remove them and the burned residues of these rings can prevent full welding and leave inclusions in the weld. It's not a problem with industrial roller chain or chainsaw chain. one_rod.

A friend asked me to make this as a christmas gift for his father. His dad likes hunting rabbits, for the table. But he has quite severe arthritis in his hands and has trouble opening the old folding knife he uses for skinning. The bulbous handle shape is designed to make it easier for him to grip. The little piece between the choil and the finger groove should stop his hand sliding forwards onto the sharpened part of the blade. It's a bit 'pointy' for a skinner but that's what he wanted, as it matches the shape of the blade he is used to. (We traced around the old blade and made a template). It's probably worn into that shape from years of sharpening. The blade is made from 52100, the handle is stabilised oak, with internal pins. It's nice to make a knife that you know is really going to be usefull to someone. one_rod.

First attempt at a Japenese-style kitchen knife. Rough forged blade from O1 steel. I love the patina that carbon steel develops after it has been used for a while. Much more interesting than stainless. The blade was annealed and then edge quenched and has a slightly concave grind, done by using a slack belt on the grinder, and working well away from the contact wheel. This way it follows the slightly uneven forged profile of the blade rather than giving a sharp grind line. The handle is stabilised oak, darkened by scorching on a on a very fine metal finishing belt. Was made as a housewarming gift for a friend. She seems to like it. one_rod.

Lucky man! I have been trying to get myself onto one of his courses for ages. Lack of time / lack of funds / other commitments always seem to conspire against it. So, from one of the small handfull of other Limeys here, welcome. This is a good place and you will learn a lot, just don't be afraid to ask. one_rod.

As you may already know, there is no "official" or defined format for RA forms. There are some common formats, which an insurer will accept without too much fuss, but outside of that it's pretty much up to the individual to just see that all relevant information is included. There is an exellent book by Peter Parkinson called "Forged Architectural Metalwork" which has some basic RA form information (to UK standards), and some sample forms which you could easily alter to suit your own situation. If you don't want to buy the book, or can't borrow it from your local library, then PM me your email addy. and I will photocopy the relevant pages and send them to you. Good luck. one_rod.

Spot the connection between these two pictures?........ ;-) one_rod.

One thing you do need to do first is check that the file you intend to use is high carbon steel. Many modern files are case-hardened mild steel and useless for making knives. Here's how I test a file. Knock the handle off. The tapered part that went into the handle is known as the "tang". Heat this part to a red heat, hold it at this heat for about a minute, then quench in cold water. Put the file in a vice with just the tang sticking out. Tap the tang smartly with a hammer. (You shoud wear eye protection when doing this). It should break off cleanly, as though it was made of glass. The broken edge should show a fine, even, crystalline grain structure. If the tang bends at all, or needs more than one strike before it snaps, then don't try to make a knife from it. It will never hold a good edge. one_rod.

I use a random mix of gearbox / engine / hydraulic oils. Machine drainings from work. The boss would have to pay to get rid of this stuff so he is happy to see me take it home. Have never had a fire in it from quenching red hot blades, provided you submerge the whole thing quickly. If you stop with half a hot item in the oil and the other half in the air then it will flare up. If you just want to blacken an item, rather than heat treat it, then it can be done at "black heat". This is just cooler than dull red and should be below the flash-point of most mineral oils. However, I always keep a dry powder fire extinguisher around the place, just in case. one_rod.