Previous Edition: >>2562551Question of the thread: Why do Pakis cast metal without wearing shoes?
>>2615694>no shoeshttps://www.youtube.com/watch?v=RRgfGkLjYSM&t=508Holy shit, you weren't lieing.
Casting after first try using the sandbox. No longer aiming for tiny pouring basins makes things a lot easier. Some defects from what looks to have been green sand falling into the molds (unsurprising since I remember it doing so. I'll see if the paper method is enough to prevent it next time.
>>2616350You can get ceramic filters for inline but for just stuff falling into the molds a thin burnable film (fine tissue paper) should work. Great results none the less.
>>2615694If i have a detailed model made of resin (3d printed) is there a way to sustain the texture when making a mold of it?
How do I make my holes more straight when drilling next time? It was two pieces of bar I was drilling through using a drill press. Unfortunately I fucked up the placement of one of the holes.
>>2615694When did the /EMT/ threads get lumped into this general?
>>2617116An extremely fine first surface coat and investment casting. But that is hard work and takes a lot of time+money.>>2617246 Well, that's a hard one. What you need is a shitty starter hole and then instead of a drill you want to use one of those insert boring heads like an inverse lathe. Otherwise you need a retard stiff setup and a retard stiff drill press.>>2617306It hasn't? I just include machining since more metals-specific (alloy selection, alloy specific requirements, etc.) questions might be better answered here. I make this thread but don't usually follow /emt/. You should make the thread if there isn't!
>>2617432>An extremely fine first surface coat and investment casting. But that is hard work and takes a lot of time+money.hmm, might as well cnc a mold at that point?
Can I cut 0,5 mm (25 gauge) mild steel sheets by scoring it with a utility knife and then bending it back and forth? What about 0,75 mm (22 gauge)?
I've been practicing Lost-Plant casting
>>2617728For low temp alloys you can try certain Silicon molds made from the printed original.>>2617745Yes, but you'll need fine hard-edges (sharp edged plate of steel) to bend against or it'll fuck up the edges. >>2617974The ferns are probably not wetting with your mold material. Try spray painting them with some kind of coating that wets with the plaster or whatever you use.
>>2617996I'm planning of clamping the sheet metal between 2 flat bars.I'm only cutting 120-200mm wide pieces here and I thought I would try this method because I can't for the life of me get clean and straight edges with the tin snips, or I can get one clean edge but the other edge looks like it was chewed off and I'm trying not to waste any material.
>>2617996>For low temp alloys you can try certain Silicon molds made from the printed original.Ah, but the issue is i need a metal mould for non making non metal parts, sorry kind of opposite of this thread if i think about it
>>2618039Ooooh, I see. Yeah, you probably just need it machined. If you make positive-negative-positive molds to end up with a two-part metal cavity you will lose an surface texture and end up with bad dimensions needing to be machined anyway.
>>2617974Super cool, anon.
>>2615694Been looking into a new TIG machine. Is the Everlast 210 any good? All I see online are people shilling it on youtube.
>>2618492As with most things in life, the answer is "it depends". Beware the shills.
I'm trying to create some tin drops/slag for an art piece, so I don't need to actually cast the molten tin into shape but I do need to pour it out onto a flat sand surface. Can I use plain sand from the store or is something going to explode if I don't get a specific kind of sand to pour ~700 degree metal onto?
>>2619133If you want to be extra safe dry the surface of the sand out before casting. With a wet surface the risk is steam will form underneath, causing the liquid metal to splatter potentially onto something or someone. But just any old sand will work. If you care about surface finish you'd want a finer sand - aquarium sand > play sand > mortar sand.
>>2619133Yeah, I know with lead it's no issue but tin is significantly hotter so small steam explosions might be a real risk, which are bad news when there's molten metal aroundI'd stick a tray of sand in the oven for a bit and make 100% sure it's 100% dry, and then obviously wear the appropriate safety gear
I made this 14k gold bracelet recently
Learned how to do it just from watching youtube videos.
>>2620282cool man good job man. attachment to clasp and finish could use a bit of work
>>2620379Yeah i struggled with that a bit because I had to make the links thinner then I expected due to gold being more dense then silver. Its the first gold piece I made. Also dont have a good dremel bit for the tight space. Here is all the leftovers which I remelted. In total i lost around 2 grams somehow. I melted 30g initially, bracelet ended up being 20g and i reclaimed about 8g
Looks good for what it is. You can always acidbath it and apply a 24k gold electroplating for enhances finish.
>>2620282Good shit man. What’s up with the arms on the clasp?
>>2615694How do i remove a screw without a head without damaging the threads? I need to have it in one piece so i can get replacements made.
>>2621759Use a dremel to cut a flat slot for a flat head screwdriver. Drill it completely through and attempt to extract it with a left-handed screw inside that screw.
So I'm making a wall panel out of galvanized steel sheets.Left is galvanized sheet metal I bought 3 days ago, right is galvanized sheet metal I bought today.They are from the same supplier, made by the same manufacturer, same specs everything.The right one is noticeably darker and duller in its colour. I got suspicious if it was really galvanized so I snipped off a piece and dunked it in vinegar and it started fizzing so there is zinc on it?Excuse my shitty attempt to take a photo through a 30X jewellers magnifying glass.Can someone explain to me why they look so different? I'm not against alternating lighter and darker sheets, it might even look better but if the plates I bought today are "defective" and don't offer the same rust protection then I'll have to return them... and bring a sample to color match the next time wtf.No this is not chingchong steel, stickers say they are made in Germany.
>>2622532The one on the right looks like it was thicker. Usually galvanized steel shows those very thin flat crystals of the zinc. The one on the right looks more like a layer of molten zinc solidified on the surface. Probably different parts of the dipping process the sheet came from, maybe the beginning before they diled in the line. Theoretically the right is better if my assumption is correct?
Crystallographer here. Ask me anything about metals and alloys.
Anybody messed around with casting 3d prints?
>>2622639How do I get grain relief contrast etches on low carbon steel? The Ferric Chloride + water method just seems to attack trace diamond scratches or edges more than generate grain relief.>>2622641Some guy in earlier threads, yes.
>>2622593Sounds plausible. The one on the right also feels a lot more grippy when you run your fingers over it.For now I will consider it a feature and not a bug and try to create some nice patterns with the different colored sheets.
>>2622641I'm getting into it. Had some fairly interesting results pouring aluminum into a 3D print of my own head. I used 1 wall, no bottom layers.
>>2622639I vacuum cast jewelry and small items typically out of base metals; what causes the visible "grain" in copper dominant alloys? It's a very striking difference when it appears but I want to be able to select for that or not. Any reading materials or resources you can recommend for a self-taught grug?
>>2615694what kind of stoves are you guys using, is a table top electric stove enough for a beginner, capacity isnt very large i guesspic related
>>2622886I use a model similar to this, works quite well, just don't be a retard and check your boiling points when alloying; I wrecked my crucible that way.
>>2622825Oh hell yeah man would love to see pics sometime what did you end up making?
>>2622863Copper alloys almost always for various Alpha/Beta structures. You see how the different orientations of crystals contract as they cool or you reveal the contrast after polishing and/or chemically treating it with acids or bases. Any base metallography book shoukd generally explain this. >>2622886I made my own firebrick NiFe wire box but it is still just a 120/240V system.
>>2615908How do you get it hot enough to melt iron? Does this work for steel too?
>>2618025That's just how tin snips are. You can get somewhat clean edges. If you want clean cuts, you need an angle grinder or a bandsaw
>>2622532If it's going outside, make sure you use cold galvinazation on all of the edges after you cut them
Burning out my molds has been a bottleneck in the casting process (and also my electric bill has been raping me) so threw together a "pizza oven" to burn them out. I cover the open part with a piece of sheet metal when not loading. In retrospect I should have built it into the side of the hill to retain the heat better (which I'll do at some point) but I've been able to maintain 400-450C so far pretty easily based on TC measurements. Big day of casting tomorrow and we'll see how the molds held up.
>>2623088>Any base metallography book shoukd generally explain this.Hm I'm not sure that trying to go from atomic theory -> crystalline structure -> practical casting is the best use of time in the general domain of cast-metal jewelry. I was hoping for a practical guide, unless that's closely guarded tradecraft, in which case very well, suppose I'll have to pay my dues in effort like everyone else.
Pains me to recycle my stack of aluminum cans for someone else to make a buck. What's the easiest way of smelting them down?
>>2623057Here's one of the happy accidents
Rate my burner
>>2623436Looks good anon. If you have problems with too much airflow, adding a gate valve between the tee and the blower may help (unless blower has a variable speed?)
>>2623487It has 3 speeds - doesn't make much of a difference in the burner output given the restriction of the 1" iron pipe. I do plan to put a valve in there but I haven't dug one up yet. Here's a pic of it turning a leaf spring orange.
>>2623159Nice. Very comfy.>>2623427Not worth it. Too much plastic, too little metal. Otherwise just use charcoal made from random wood you find and natural clay (or mud) furnaces or it will be a waste of money.>>2623436Switch that out for an "e-duster". 1/10 the size and twice the airflow. >>2623435It has become art. Mount it on a nice base.
Does that rust remover liquid work the way Youtubers show it working? What chemical reaction is it?
Evapo Rust worked pretty good. But I'm the kinda guy that just oils his rust as a good oul holding surface.
Okay, so I got 27 oz. of gold jewelry for $70.00. My friend has a crucible and smelter for metal smelting, I'm going to buy about 80 oz. of silver scrap, $250.00 in nitric acid, hydrochloric acid, sulfuric acid, and sodium metabisulfite. All of that will be used to refine it to maximum purity.At the end of this process, I hope to recover at least 11 Troy oz. of gold which I can make into a small bar.That's about $21,000. I know I'm not gonna be able to sell that for that much, how ever I can cut it down to like $4000 or $5000.Am I being delusional and is this worth it?
>>2625951Assuming your gold jewelery isn't copper and you bought 27oz of, say, 10k junk for $40? Yes. For $40 + reagents you would hit even if your gold is even, like, 2oz.
>>2625951Thats absolutely worth it but I feel like you're not going to recover that much pure gold simply because you got it so cheap
>>2626131Looks like it, pretty good quality.
>>2626131Yessir, but with none of those damn minarets.
Anyone got a good thermocouple temperature gauge setup recommendations for a propane furnace? looking for something under 100 dollars and amazon is looking like a straight grab bag.