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Kang

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About Kang

  • Rank
    Master
  • Birthday 01/17/1973

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  • Gender
    Male
  • Location
    Ottawa, Ontario, Canada
  • Interests
    My wife and kids, backyard metal casting, A Song of Ice and Fire, minis

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  1. Kang

    Boxer Rebellion: Box-Turtle Folk, WIP

    Loving the druid so far! She's gonna be super cool. Too bad about the brazing and pewter not working out like you hoped. You may not need a full burnout of the investment to cast lower temp. alloys. I'll ask a friend who does a lot of small pieces with lost wax if he's ever done anything with pewter and report back any info I can dig up. He's been really busy lately renovating his new very old house though; could take some time to hear back... Update - I heard back: Dave says for pewter, burnout is as usual for your flask size and investment type, but pour when the flask has cooled to 260C. Hope that helps, good luck! Kang
  2. Here is another bronze casting with liver of sulphur patina, alongside the belt buckle. Same bronze. Same LoS. Totally different colour! Weird. I did do one thing differently: the belt buckle was sealed with clear spray polyurethane, and the ashtray was sealed with wax, which IMO gave a much nicer finish due to not being so glossy. Maybe people will find the pic helpful as a painting reference. Most time people add a patina effect to minis, it's a blue-green verdigris type of patina. From what I have noticed anyhow. Fact is, patinas come in a wide variety of different colours, and not every dunegon lord cares so little for his art collection that he will neglect his statues until they look like they have been crying blue-green verdigris tears for a couple of centuries. :) Anyhow, there is video too. It shows what the castings looked like before and after as well as how I applied the patina. https://youtu.be/4Bw2TqCFygU Note, liver of sulphur is NOT non-toxic. I am not sure if it would work on pewter if someone wanted to try shading a mini this way, perhaps it would. For sure it is used on silver and some other copper alloys. If you try it, maybe try applying it cold, which may be slower. Pewter melts at a much lower temperarure than bronze. That said, I was aiming for about 200F with my weed burner torch which should be safe dor metal minis (I think), but I got parts of it hotter than that for sure at certain points in the process. Kang AKA Tobho son of Timmett
  3. I finally got a chance to try my hand at patination! Here is a liver of sulphur patina applied selectively using a hot process (there was a weed burner torch and a lot of sizzling involved, what fun!) to one of my silicon bronze skull belt buckles. To add shading, so to speak. For the highlights, I buffed the patina off first with a scotchbrite pad, then more selectively with a wire brush drillbit. Simple as that. Then once it has cooled, a coat of spray polyurethane to seal the piece and stabilize the patina. That came out a bit glossier than I'd hoped, but I can live with that. Wax would be the more typical choice of sealer; I used what I had handy. Let me know what you think! Kang AKA Tobho son of Timmett
  4. Kang

    Neutralizing Gloss Varnish?

    Dullcote and similar sprays can go glossy or satin if you are like me and tend to apply sprays too thick. I switched to RMS matte sealer rather than keep struggling with spray cans. Works great, thin to taste; just make sure to always mix it really well before use or the whole bottle will go bad on you eventually. Brush on primers for me as well. Kang
  5. Here is testing the sand, part 2 of 3: https://youtu.be/Ne086_NHbjQ And here is part 3 where I finally nail down a recipe that really works. You've already seen the results, the bronze skull pic in the previous post: https://youtu.be/BtRTArVb2lE That's all for now... Kang
  6. Well, the testing and tweaking of the new molding sand is complete. I have gone from crumbly sand producing bronze pieces encrusted with sand like this: To nice and sticky sand producing nice clean smooth castings like this: The mold ran out one side when the hydrostatic pressure of the molten bronze caused the top half of the mold to float. I thought the casting was lost for sure, but a moment later just before pouring ingots I remembered the whole part was molded in the bottom half... Figuring the metal that ran out would have frozen by then and blocked the gap, I resumed pouring and somehow the casting was saved! Not one bit of burned on sand. Not one little bit of flashing either. Umm, unless you count that runout. :) Video of part 1 of the sand testing follows. Have not yet edited the next part. https://youtu.be/77xeLY18Nas Kang
  7. Kang

    Boxer Rebellion: Box-Turtle Folk, WIP

    Too bad the bronze you got isn't cooperating so well for making the armatures. Have you tried annealing them to soften the bronze so it is easier to work? I know it works for copper... Kang
  8. Kang

    Sculpting and casting

    Awesome! So did you print the zodiac stuff with wax filament, or do lost PLA casting, or did you print them then make a silicone mold to cast the waxes in? However you did it, the castings look great! Kang
  9. Love the pony, great job! Kang
  10. I'm more angry at myself for pulling a dumb move out of nothing more than just laziness (not wanting to have to melt more bronze after pouring) than I am in pain. No signs of infection so far thank goodness, I'm keeping a close eye on it. I was taking to my friend Martin from Australia (aka Olfoundryman on YT) and he told me he'd gotten a teaspoon of cast aluminum down his shoe once which took 6 weeks to heal. Mine happened about a month ago now and the wounds are smaller than they started out, but still very much holes in my foot. The short video of the spill I linked above is unlisted, I just uploaded it to show friends who are into this stuff in the hopes it might keep them from making the same mistake. I've since edited a longer video about the accident with a lot more fire and molten metal. Same message, but maybe more entertainment... https://youtu.be/Fq9i9WRuIrA How do I like the Everdur? I love it. Even though every sand casting I've tried to use it for has been a failure, it's amazing stuff. I went to skim the dross of the first pot I melted before pouring, and there just wasn't any... The surface of the melt looked like an orange-yellow hot mirror already! One of those molds actually was an attempt to cast a silicon bronze axe... I know a guy who really wants one shaped like mine who asked me if I could make one for him in everdur. He wants some kind of bronze cap to go on the other end of the handle too, something with skulls on it. Pretty sure it's just going to be a wall hanger, so holding an edge well would be nice, but not really necessary in this case. I haven't designed that cap yet, so I've got some work to do there... So while those were all test castings, if that one had worked it would have been really nice... Since then I've made some adjustments to my molding sand. The new recipe is 2% calcium bentonite clay, 2% sodium bentonite clay, 1% dextrin, 1/2% "sea coal" (actually finely ground bituminous coal dust, should be similar), balance fine dry screened silica sand. The addition of the dextrin made a huge improvement in my sand's green strength. I haven't had a chance to try casting anymore of the bronze to see if the seal coal works to stop the sand from sticking to it. Even the dextrin may help with that. My old sand from the foundry supplier doesn't do that, so I know it can be fixed... Here are a couple of test castings in aluminum from the sand after I tweaked the recipe: (Other side says "drink beer" if you hadn't guessed, lol.) They look a bit rough but some of that is from the rough patterns I used to make the molds (cheap imported cast iron from the hardware store once again, like a lot of my test patterns. They work, but cast aluminum might not be the best choice for bottle opener metal). However the silica sand I used to make the new greensand is a bit more coarse than my old sand, so that may also be a factor. I'm planning to cast one of my really smooth patterns next to see how smooth of a casting the new sand is capable of. I also learned I had been mulling my sand in the wrong order (mixed all dry ingredients, them mulled in the water). Should have been mixing the sand and water THEN mulling in the binders and other additives. Anyhow, just need one or two more tests to check how the sand works for bronze now, and for smoothness.
  11. Was pouring more castings just to test my sand, big dummy that I am sometimes, I chose to fill my crucible right to the top with bronze because I did not want to have to take the time to melt a second pot of bronze. A #12 crucible brim-full of anything hot is too dangeous, but full of bronze it's also heavy enough to be hard to control. Splash! Hello 3rd degree burns on my right foot. Luckily I had my leather steel toes on or I'd be an even bigger dummy with it 1 foot. Shoes took no damage, the worst 2 of the 3 burns happened right through the leather in the amount of time it took for 2 small molten BB's to bounce off my shoe. Video shows my crispy feet, don't click if you're squeamish about feet or seeing fresh burns. Talespinner, please take note and learn this painful lesson the easy way! https://youtu.be/D2gZ__5kIBQ I did pour all 3 molds in bronze then melted a pot of aluminum for the last test casting of the day before I went in for bandaids and beer. All the sand castings were failures, but I got some good data about the new sand. Namely, it does stick to castings more than my old sand does, and it does not have the same green strength (ie. stickiness). Now researching sand additives I can use to correct these... Such as sea coal (bought a bag of bituminous coal dust - a rough equivalent - from a local blacksmith whose existence I just discovered) and dextrin (baked cornstarch, made some but stank the house up because our oven is hotter than it says it is) and a different type of bentonite clay (calcium bentonite) than what I had used as a binder in the sand I made (sodium bentonite). The clay is for the strength and the others are to stop the sand burning onto castings. This was 2 weeks ago. Foot is healing well but slow. I'm back in socks and shoes now, no more wearing my slippers to the office like last week! :) Kang
  12. Kang

    Boxer Rebellion: Box-Turtle Folk, WIP

    Wow, haven't checked in for several weeks, so much progress! A dragon shaped helmet sounds very cool... Really though, I'll be happy enough no matter what, as long as they actually use their weapons on their enemies, not just to cut the rope that causes the chandelier to fall and entangle Rocksteady and Bebop. :) Kang
  13. Rammed up a few test molds over the weekend and cast one of them in Everdur silicon bronze. My first time casting this alloy as well as the first casting poured in the new sand. Also made up an ingot mold with some of the new sand. Also made a couple of styrofoam skull belt buckle patterns to cast in the same bronze alloy. The new sand did not have as much "green strength" as the commercially made sand I'm used to, meaning that the molds were more crumbly. The sand casting and ingots came out of the mold with the sand stuck to the castings in a thin layer that I had to remove with a wire brush. Sand that does this is known as having poor 'peel'. Carbonaceous sand additives like powdered sea coal are known to improve peel, but is normally reserved for ferrous (iron/steel) casting. I need to level up a few times before taking a run at cast iron, cripes I almost burst into flames manupilating a crucible containing 30# of molten silicon bronze! That's closer to 1000 than 500F cooler than cast iron. Organic additives are said to improve peel, and corn flour supposed improves green strength... So I'm thinking of adding some so that it makes up maybe 1% or so of the sand's dry weight. The ingots has scabby looking marks on their undersides which I have identified as being caused by metal penetrating into the sand. Maybe I could have done a better job ramming up the I got molds, no big deal. I'm far more bothered by the peel. The sand casting did not fill, but I had not added any venting to the mold, and the same casting in aluminum had failed to fill in similar fashion when I molded it without venting in the old sand too. The bronze also has pinholes in some areas which could come from all sorts of things, but I suspect my having left the mold to sit overnight and dry out slightly was a likely culprit. I was surprised how brown the casting came out of the mold, like it had been given a patina. My aluminum bronze axes always came out looking like shiny metal, but then, non-molten aluminum bronze is resistant to oxidization and will not take a patina easily... The belt buckles... One was a great success. The other, a dismal failure. The Dreaded Sand Float strikes again! I knew it was a failure when I saw the sand on the surface of the mold get pushed upwards from below during the pour. Sand Float defects are so weird! The top part of the casting in the mold gets pushed upwards on a raft of molten metal, separating it from the bottom part. - See how one side of the belt loop stayed right against the back of the slice of skull, while the other side got floated? So bizarre... Back to the lab to see what I can do to get my sand working right... I thought building a muller would make it easy to make my own greensand. Turns out it also makes me have to do a whole bunch more research on what actually goes into good greensand. Lucky for me I enjoy this sort of thing... Here's about a 15# ingot preheating next to my dross skimmer by the exhaust vent in my furnace lid: One more craziness that happened during that session: See the turnbuckles used to support the weight of my furnace lid? I found out their tighteners are NOT made of steel when BOTH of them melted and fell apart halfway through melting the bronze! Kang PS. All pix were taken after I brushed the stuck on sand off the castings.
  14. Last post was Big Bucket Mull chewing up some old greensand to bring it back to life; here is the true test of his functionality: making new greensand! https://youtu.be/CNzKwx2Qb0s If you enjoy watching noisy machines go round and round, you might just get a kick out of it. Here's a pic of a test mold half I rammed up after making four 15kg (dry) batches: All in all, a great success. Woohoo! Next upgrades will be to attach a repurposed microwave oven timer so I can set the muller to run for so many minutes then automatically stop and beep at me to let me know, as if all that racket suddenly stopping won't be enough of a clue... And casting a wider wheel so it will roll over twice as much sand with each revolution. Kang
  15. Oh gosh, seems like I forgot to post the video where I installed the second scraper! Well, too late now, you can find it on my YT channel if interested, but this one is gonna be way more fun to watch... which may not really say all that much. Well, maybe not, the last one did have my first attempt at blacksmithing in it, which was a lot of fun... Which you would think I would do more often, given that my youtube name is Tobho Mott... If there were any metal casters in the (ASoIaF) series, I'd have used their name instead. Drogo vs. Viserys doesn't count; there's no way you can melt gold medallions in a soup pot over an open fire like that, sorry George. Anyhow... so, we had a nice weekend, rain free for a change, at least until after dinner on Sunday... Point being, I actually got to put my Tobho Mott hat on and get some work done out in the Forges of Qohor (Northern Branch), AKA my backyard foundry! Long story short, I finally got the muller working, and chewing up some real greensand! Short story long, there is video! Ok the forum is not giving me the usual option to display that as a link instead of an embed. If a mod could fix, I'd be very grateful. It won't even let me remove it! Not quite working perfectly yet, but it is working and it is mulling sand. The one change I made to the muller before testing it with real greensand was rotating the 2nd (center) scraper a bit to improve its angle. So far I've only used it to recondition my greensand (purchased from a foundry products supplier here in Ontario), not yet for making my own greensand from the ingredients pictured earlier. I wound up putting way too much water in the first batch, and maybe a little too much (not 100% sure) in the second. Pictures! Mixing dry to see if it will break up lumps (it does this better with water added, though the big lumps take some time to make their way under the wheel either way): Way too much water: Squeeze test: far too wet but super sticky! Another batch, used less water this time: Seems to handle half a 5 gallon bucket of greensand just fine, though 3/4 of a bucket was too much for it when it had way too much water in it, it got so sticky (technical term: "stickier as frig") it just sat there in a big clump when I tried to dump it, the drum kept turning but the sand held together and let the drum just spin/slide under it and would not turn over. That part is at about the 12 minute mark if anyone wants a laugh at my expense. Still getting used to just pouring the water in I guess; I always used one of those little pump-up garden spray bottles before this, to add it as more of a mist. But with a muller, that is no longer necessary. Youtuber Olfoundryman, one of my home-foundry heroes, left a comment saying I should ease up on the spring tension because he thinks my wheel is pushing sand to the side instead of rolling over it. He does not use a muller but he REALLY knows his stuff; Youtuber Chirpy's Tinkerings (a friend and fellow metal caster) thinks I need a wider wheel, and I do not disagree; Youtuber Worldtraveler (another friend, who does lost wax casting) says I was right about moving the wheel over an inch so the whole width of the wheel is rolling over the area where the sand was sticking to the wheel as it stands now, rather than just half of it. I'll agree with basically anyone who says I'm right, so that's good too... :) I'd like a wider wheel and IMO that would accomplish the same thing as moving the one I have over a bit as well as making it harder for sand to get pushed to the side... I would cast one if I had a lathe to finish the job. Or I could buy another wheel like I have and put them side by side, though they would have a gap between them. A guy on one of the casting forums suggested I could cut off the part of the hubs that stick out past the edge of the rims, to make 2 wheels able to sit flush against each other and not leave a gap between them. It's a possibility... I think it is working pretty well, so any more changes would be just to make it work a little better, or perhaps work just as well only a bit faster. Mind you I haven't tried making new sand yet, possibly I will learn about more flaws in my build when I try that... Hope you guys are enjoying this look at my OTHER weirdo hobby... Kang
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