I love this stuff, guns are so restricted here in Australia, I plan on making some for fun, I'll just have to hide them ,or have them semi disassembled.
over the top for home furnace. as menttioned theres messing with it that can be avoided. i also saw you fail to point the crucible in the correct directtion prior to smelting in two videos. your seen spinning and repositioning crucible ... haste makes waste.
If you melt your scrap into ingots first, you won't have to screw around with skimming the melt the second time around. You should use cast scrap, not extrusions as they are alloyed differently. Nice furnace and nice flasks!
Why were you using the cope for the drag, and the drag for the cope? It's much easier to strike off the drag without the guide pins sticking up. Otherwise very good video.
can you use bronze or cast aluminum to create a chamber that holds a charge of around 150-200 psi for use in a paintball musket or should I use machined steel?
I want to add if anyone is concerned with metal going through clothing. Just misting lightly with water will cause any metal to be deflected. As soon as metal hits water it will form a layer of steam just like water droplets on a very hot pan. It will have almost no friction.
to do the same thing u did do i just put my pistol slide on the sand and cover one half then the other? will this work? or is it possible to make a bretta 92FS slide
+Esteban Geraldo I'm working with aluminum, a berreta slide is steel. Even if you cast a part, there will still be machining involved. to do a complex part like a slide with undercuts and everything would require investment casting.
Finally someone using the proper safety procedures! So tired of seeing guys wearing flip flops or sandals when pouring. My personal problem is my choice of crucibles. I keep blowing out the bottom. I've used cut in half blow torch and lantern propane tanks and I guess my heat is too high cause I've had to salvage two good sized loads of molten aluminum from the bottom of my foundry.
I would suggest that you use clay graphite for lift out crucibles. They are stronger at high heat than silicon carbide. One, such as you have, is more typically used in a tilt pour furnace. Silicon carbide is quite fragile compared to clay graphite. The screen face shield you have is a bad idea. Although it keeps away the heat, aluminum from a steam explosion, will go right through that. A person at Federal Mogel Corp. was blinded when he used a screen without safety glasses below it. The screen merely dispersed the metal into fine droplets. We use clear plastic shields, though you could also use a tinted one. You might also think of using a fireproof apron, such as leather or kevlar. In a steam explosion of aluminum, you could severely burn your private parts without that protection. I could not see your boots. Use a kick off boot. Sometimes aluminum can get past your spats and into the boot. A kick off boot will keep the third degree burns to a minimum, if you get it off right away. Wear wool or cotton socks only. Nylon melts and then sticks to your skin. You should consider painting your pig molds with something like Mica Wash from Springfield Coatings or bone ash, which can be bought at some garden supply houses. Mix them with water and put on with a brush. Wait till dry. Pouring the aluminum into an uncoated pig mold results in iron contamination of the aluminum. It also reduces the life of the pig molds and sometimes results in the pigs sticking in the pig molds. Be sure that the pigs are completely dry before pouring metal into them. I always pour the first metal into a pig very slowly and at the edge, to help prevent a pig from blowing. Sometimes pigs will blow just from condensation of moisture in the air. When they do blow, it sounds like someone fired a shotgun. The metal goes extremely fast and long distances. We have what looks like stars stuck to our ceiling. Ours is made of tile, so it doesn't set the building on fire. Although we try to be extremely careful, it always seems like new guys want to learn for themselves. We always stick handles from old scrap runners and gates into the top of the pigs when they are just starting to solidify, to make them easier to pull out of the pig mold. We mark our runners with the alloy number to keep alloys from getting mixed up. You are pouring way too hot. From the color, I would guess that you are close to 1600 degrees F. Typically, you should be pouring around 1300 to 1350 degrees F. At those elevated temperatures, you will end up with a lot of hydrogen porosity. Those degassing tablets you use will not help much at that temperature. The hotter the metal, the more hydrogen it will hold. The hydrogen comes from moisture in the air, or from the combustion products of your fuel, reacting with the aluminum. The aluminum is so electro negative, that it will strip oxygen from water. The hydrogen that is released, dissolves into the aluminum and comes out when the metal drops below 1250 F, producing small bubbles throughout the casting. You can help prevent hydrogen pickup by using a cover flux, such as EcoFlux 145 from HA International. Put this on top of the metal as it is melting. We degas our metal with nitrogen or argon, using a hollow graphite rod, a hose and pressure regulator. Bubble the nitrogen or argon through the metal for around 5 minutes before pouring it. We use type 1 graphite rods from Pyrotek. You should be using a drossing flux which you stir into the metal, before pouring. That will pull out a lot of the oxides that are in the metal. As you mentioned before, do not melt magnesium in this type of furnace. You most certainly will set it on fire. The 5000 degree plus, flame blowing out of the crucible will break the crucible, melt the furnace and set anything near the flame on fire. If you were using a propane tank near the furnace to fuel the burner, chances are that the propane tank will blow as well. You do not have the right protective gear for that level of heat. Magnesium needs to be melted in special furnaces and you need to have a steady flow of nitrogen across the surface to keep the air away from it. In the 1950s, several aluminum foundries in Detroit started pouring magnesium. All of them burned down by 1960.
+8MADJACK You probably will not see the porosity unless you machine the parts with a carbide or diamond cutter. I'm in the business, so my metal has to be high quality.
yea i know :) well if i make a scale it isnt really that big, but only way to know is to see it in real life :) also just had a question, you might know of somekinda crucible in wich i can melt ferrous and non-ferrous metals? because im finding crucibles that only have 1 a kind.
+Gamers House The one in the vid is clay graphite, we used it for cast iron if I remember correctly, been a while since I've done any casting. there were some good forums on casting but I lost a lot of the links with my old computer, google should help, there was a guy named lionel I think that had a good site. also look at budgetcastingsupply.com for info on their crucibles
Nice foundry, 8MADJACK! If you like homemade tools, you're always welcome on our homemade tools forum :) Our members would love to see more of your builds -- www.homemadetools.net/forum/?.com&
Have you tried making your own castings of AR15 uppers or lowers yet? I'm kicking around the thought, when my furnace is completed, possibly including one in .30.06 length.....
Kevin S I played around with atttempting a brass lower, it didn't work out, but the idea is sound. personally I like the forgings as they are stronger so I haven't messed with it otherwise.
Thought you might like this one, scratch built Cast Aluminium fully articulated T800 Endoskeleton. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-SWOwR7CS6NE.html ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-nfNtscIeYT8.html
Are you using investment castings ("lost wax") technique? If so, do you have a post with the burn out process? Your technique is often either overlooked or not aware by other hobbyists that generally spend excessive time on milling, etc. BTW: Car restorers are quickly discovering this technique, since they can make a negative image of an original part, make it in wax, then cast numerous copies.
"Home Workshop Guns" series is what I have. Never made anything out of them, but I could if I wanted to. There are very detailed spec sheets and materials lists.
Wow... I'm attending to a Mechanical Engineering College here in Brazil too... and the name of my country popped out in my sight on the very first comment... it seems you have many fans here! Cheers from South America!
