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Showing content with the highest reputation on 03/14/2023 in all areas

  1. Appreciate the advice, I'll let you know how the next run turns out! Yep, great color. I've seen it bring in big bass in southern ponds and big walleye in clear northern lakes. Hard to beat!
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  2. Beautifully done. I don't know how you got that mottled pattern on the sides and back but it looks great! Congrats. Barry
    1 point
  3. Tungsten fishing weights are not machined, nor are they melted and poured in a mold. Unfortunately, the method of manufacture is beyond most individuals and home-businesses. Tungsten fishing weights (and virtually all other tungsten parts, rod, or plate used in manufacturing) are made by a process called 'compression forming.' Tungsten powder is poured into a die that is the desired shape of the finished product, and then using a hydraulically-powered ram or punch, the powder is compressed under enormous weight until the powder becomes one solid piece. The solid part is then ejected from the die, and carefully set aside. What you have then, is a tungsten fishing weight that is about as hard and strong as an aspirin tablet. To make it strong enough to be used, it needs to be 'sintered.' Sintering involves heating the tungsten part in a furnace until the compressed powder just barely starts to melt, which essentially solidifies the part, and makes it strong. Now, since tungsten's melting point is so unreasonably high, the tungsten powder used for compression forming has to be mixed with another metal that will melt during sintering. This is usually a few percent of copper, nickel, or iron, but other metals like tin are sometimes used. The small amount of copper powder (or other metal) in the mix is what actually (just barely) melts, and binds all the particles together. For some applications, the compressed tungsten powder/metal mix is so strong after compession, that it doesn't need to be sintered. Also, tungsten powder is very hard, so it tends to clump together and won't flow through the machinery very well and scratches the dies, and the addition of the copper/nickel/etc makes it less abrasive. Often a tiny amount of stearate or a special wax is added so the metal powder is easier to handle, and flows into the dies easier. If the part is going to be machined after sintering, the addition of copper and nickel make it MUCH easier to machine with cutting tools-- pure or nearly pure tungsten is very hard to work. Even very large slabs or or rods of tungsten for industrial/military use are made by the compression-forming process, and sintered. Tungsten compression presses are available to individuals......... if you want to spend the money. Don't quote me exactly, but compression presses start around $7000, specialty dies run about $500+ each (you'll need more dies than you think), and you'll need all kinds of other equipment to go along with the press. Add a controlled-atmosphere furnace to the list. Tungsten/copper powder usually has to be purchased in 100lb lots to get even a half-way decent price, and even then it's still expensive. Some individuals do actually make their own compression-formed tungsten rifle bullets (usually for long-range competition) at home in their garage, but as noted, it ain't cheap. The high price of tungsten weights is simply because they're expensive to make. Tungsten can be mixed with epoxy or thermo-setting resins to form parts, but why? First, you don't get the density of tungsten, because of the addition of lightweight epoxy resin, and you don't get the 'feel' of tungsten, because the resulting metal/epoxy mix isn't hard like tungsten. The most you get from a tungsten/epoxy mix is a "lead-free" weight or lure, and you're probably better off making do with tin. Tungsten can actually be melted using an arc-furnace. If you're very clever, you could possibly make a tungsten-melting arc-furnace out of an old stick welder-- this has been done by hobbyists to melt very-high-melting-point metals. However, once you did get it melted, you really couldn't do anything with it. You'd just get a small blob of tungsten. At best, you could melt down a couple tungsten fishing weights into a shiny round blob, and then show all your fishing buddies how smart you are . Hope this helps. Good luck!
    1 point
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