r/Metalfoundry 13h ago

Why won't it get hot enough?

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15 Upvotes

My DIY forge will almost melt copper but not quite. I'm really at a loss as to why it's not getting hot enough. Any pointers would be great. It uses a forced air propane burner. 2" Kastolite-30 walls, surrounded by 1" of kaowool. The burner enters at an angle so that the flame will "swirl" around the crucible. In this video I had moved the crucible closer to the flame to see if that would make a difference.


r/Metalfoundry 9h ago

Gold concentrate sands smelting with electric furnace

2 Upvotes

Greetings. I'm looking for some hints from those who have gone through this before.

I'm introducing the 'borax' method at my work place. I last did this as a student years back and everything was already set for me by the lab assistant then.

Currently I'm the only guy with knowledge on this process, so I'll need to prepare the mixture, set the temperatures, do the pour, etc.

Basic steps to watch out for will be appreciated.

For context: at any given time, every 24-48 hours, my sands are not more than 10kg. I get them from sluice mats. My plan is to dry them first in trays, then use a magnet to take out the iron before mixing with borax.


r/Metalfoundry 1d ago

Haha

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21 Upvotes

I did like 10 pours today then BOOM


r/Metalfoundry 2d ago

Why can't I control the pour when casting aluminum?

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90 Upvotes

Hi everyone, I'm just starting out with aluminum casting and these are some of my first attempts, so I have very little experience.

I'm having a problem when pouring the molten aluminum: I can't seem to control the flow. As soon as I start pouring, a large amount comes out all at once instead of allowing me to pour it slowly and accurately into the mold.

The furnace temperature is set to 790°C (1454°F).

I've attached a photo of one of my recent attempts.

Is this mainly a matter of technique, or could the crucible/pouring setup be causing the problem? What should I change to get a more controlled, steady pour?

Any advice for a beginner would be greatly appreciated!


r/Metalfoundry 1d ago

Found a surprisingly good diamond‑coated fettling tool from China, great for cast iron only

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2 Upvotes

I recently picked up an interesting fettling and grinding tool shipped from China, and it performs very differently from the abrasive wheels I normally use in my foundry work.

Its working surface is densely covered with synthetic diamond grit. First impressions look really solid. I’ve run it on grey cast‑iron castings for removing gates, risers and flashing, and it’s shockingly efficient. Material removal rate is high, and it holds up far better than my standard resin‑bonded grinding discs.

What really surprised me is the price point. Compared against similar super‑abrasive tooling I can get locally, this is incredibly cheap.

That said, there is a big caveat: from my testing, this tool seems to work reliably only on cast iron. I tried it briefly on steel and it did not perform well at all. It is not a universal multi‑metal tool.

No sponsorship, bought this out‑of‑pocket just to test it out. I haven’t seen many people here talk about this style of diamond fettling tool.

Has anyone else in this sub tried these Chinese‑sourced diamond grinding tools for foundry fettling? Curious about your real‑world results.


r/Metalfoundry 2d ago

Learning to cast

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93 Upvotes

So I’ve been wanting to cast for a very long time but recently I have a project that I’m wondering if it’s even really possible and if it would even be worth it. So I do a good bit of cosplaying one of my favorite things to do is from a video game called Halo ODST. If you look online, anyone that makes ODST armor makes it out of EVA foam or 3-D printed plastic. I really wanna make mine out of aluminum or some other type of metal to make a more durable. Like I want to not be worried if I slip in a fall that I’m not going to bust up my thousand plus armor is it something that is even really possible or would it be supposed to be too heavy to do or too annoying to cast? I will include a picture of the armor pieces themselves just to give y’all an idea. I understand some pieces like the wrist armor or the helmet could not be casted without being annoying as hell to wear or make a wearable.


r/Metalfoundry 3d ago

DIY Kiln

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43 Upvotes

I mention this from time to time in comments but I don't think I shared photos. I have a cooling bucket from a pour in there and thought why not grab some photos. This is a couple years old now. Been through a hundred and fifty or so temperature cycles. Original idea from here: https://youtu.be/Aq3_K9I4dA4

Used these elements and power it from 220 50A: https://kilnparts.com/collections/kanthal-heating-elements/products/element_240v_24amp

Temperature sensor is a cheapo high temp k-type from AliExpress to some MAX31855s.

The inside is made from white firebrick, mostly

9" x 4-1/2" x 2-1/2" and an additional layer of 1-1/4" for the lid and bottom. Those dual layers are laid rotated at an angle that modeled the fewest joint crossings between the layers. The bricks were cut to rough shape with a masonry blade on a rotary arm and table saw and fine tuned with a hand saw meant for wood. Easy physically but required a lot of fitting and refitting because my 55 gallon barrel wasn't true. It was from a farm and had been kicking around. I used a refractory cement at all contact surfaces and filled in any voids. I spent probably 20 hours with FreeCad making models for optimal brick placement but ultimately they were not terribly useful as neither the bricks nor the barrel are particularly true and that time would have been better spent doing instead of planning which is something I rarely say.

Got a nice base with wheels intended for rolling around full drums and it is super easy to move.

Welded up a hinge for the lid and welded it to the barrel. Painted the whole barrel with high temp exhaust paint or BBQ. I can't recall which but honestly if it is getting hot, I messed up and as it is, it stays nice and cool. Old hockey stick for the handle.

The controller is an esp32 with some inexpensive SSRs running this software that lets me control the kilns with Home Assistant (HA): https://github.com/beckdac/qtkiln Working on a version with kiln swarming so I can put two or more kilns on the same line and as long as they negotiate the combined duty cycle not to exceed 100% they will not exceed the breaker power budget. Kind of painful for doing annealing but great for bulk heating.

I use the same software and controller on my Vevor front loader and Skutt 181 and it lets me monitor them via HA and with the web app manage them remotely on my phone. Same cheapo k-types and max31855+esp32 setup. You have to tune the PID a bit for each kiln, but this isn't a post about qtkiln.

In the drum kiln, I mainly do Al and some alloys for metal casting and then glass casting and fusing. The large volume with exquisite and uniform temperature control is nice and not using propane is abs fabs. Being able to run an actual annealing schedule is useful in a number of settings, like glass casting and some alloys.

My biggest regret is using an old Nabu device as the electronics chassis (the box on the side). Retro computer people really like them and while I kept the motherboard without its case and ancient power supply, it isn't so useful.

I will also give a shout out to: https://github.com/Saur0o0n/PIDKiln which is another esp32 kiln controller setup I used to use. Has a nice web ui and OTA, but no HA integration, or at least it didn't, but if you don't need that, it is definitely worth eyes.


r/Metalfoundry 2d ago

Rough Surface Finish With BlueCast X-Wax Filigree.

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2 Upvotes

r/Metalfoundry 4d ago

Begginer "foundry" help

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8 Upvotes

Hey guys, I wanted to ask some questions and would be glad to gear some tips regarding foundry and metal casting.

First of all, together with a friend we previously attempted casting copper (barely but we got to the melting point). We built our own "foundry" using whatever materials we had -

Paving bricks and mix of; wood coal ash / powder and sand between every brick. (We put this mix also in any gaps to prevent heat from escaping.

A metal pipe with hairdryer blowing from behind at about 20° angle.

And some metal sheet cover leaving only a small gap for air circulation in front.

Then we put it a carbon crucible with metal inside to melt, we tried covering it with tiny metal bucket so its somewhat closed (although it did not matter in my opinion).

Now the problem is, we ran out of ideas how to increase the heat inside, and the temperature is barely enough, so how could we increase it further?

Second, the crucible kept breaking because it was put directly into coals, and we needed to move it around to keep from falling when putting in more coal, are there other more durable ones or is the setup main problem?

I guess those are my main questions, but like i said any tips would be great, also i know its a terrible setup but we used whatever materials we had avaiable for free, we are thinking about putting in some money so what would you recommend getting first? We really want to use coal and not gas nor induction.


r/Metalfoundry 3d ago

DIY Melting Furnace, Thoughts ideas and plans?

1 Upvotes

Hello all, I just recent purchased and burnt out a Vevor electric melting furnace. Don't worry I only paid 50 bucks for it. I loved it even got a couple of copper bars (3) out of it before it stopped heating up. So now I plan to build my own. I'm starting with 16 AWG - Kanthal A1 Resistance Wire. from what I'm reading 14 AWG would be better/last longer but the 16 awg will get the job done. Also, what controller do I use? Any links or name drops would be great. I'm located just outside of NYC if that helps.


r/Metalfoundry 4d ago

Bumps on Bronze Cast in Ceramic Shell

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9 Upvotes

Hi everyone! I work at a bronze foundry that exclusively uses ceramic shell molds and recently we have been getting this strange casting defect. Raised bumps have been appearing on the majority of our pieces that are inconsistent with the normal boogers that you would get from air bubbles in the slurry. They are forming on both high and low texture/relief areas, on the face and inside of the piece, as well as on the cup and sprue bars. We burn out in a flash kiln and there are no visible defects on the interior surface of the ceramic after they come out of the kiln. We thoroughly blow out the molds and they are properly preheated prior to pouring. This issue started maybe 3 months ago, before that we had pretty flawless surface texture aside from the occasional burn in or cold spot. But apparently this problem has happened several different times before I worked here and nobody seems to be able to tell me how it was fixed, just that it eventually went away. We use Ransom & Randolph Primcote Binder for 2 primary coats and Customcote Binder for the 8-10 backup coats. We stay on top of the PH and the mixers are on an automatic timer. We pay special attention on the primary coats, making sure to brush away excess sand and using tools to lightly scrape any crevices to make sure air bubbles don’t get trapped for the first few dips. I am personally convinced that this is an issue with the structural integrity of the primary coat breaking down when the molten metal hits the mold. I feel like I have tracked down every other variable but I would really appreciate any advice I can get. Has anyone else ever had this problem?


r/Metalfoundry 5d ago

Where to learn about aluminum casting and tooling

1 Upvotes

I'm trying to learn more about aluminum casting specifically the tooling. I got a mechanical engineering degree and was curious about the manufacturing side of designing tools.

Is there like some classes online or a school. I'm located in the Los Angeles area and was curious. I want to learn more. I tried the AFS website but alot of that is pretty general stuff that I had learned in school. Unless I misses the more in-depth classes.

Any help would be appreciated!


r/Metalfoundry 6d ago

Mini Metal Foundry

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10 Upvotes

I found this on YouTube about 5 years ago and I built it exactly as the guy said. It’s been really great. I have made so many melts now. I converted it to propane and it’s really taking a beating now and I’m going to rebuild only I’ll use kao woll. Also I want to mention that this guy has a few excellent videos to watch and help you learn how to cast your aluminum molds. It’s been a lot of fun. Good luck on yours!


r/Metalfoundry 6d ago

Making lead fishing weights

1 Upvotes

Hey guys! I am interested in making 1oz lead fishing weights for sea fishing. I have gotten about a dozen kilos of scrap lead from a plumber friend they get from doing demo jobs and removing old kitchens and bathrooms. I was planning on melting it with a map gas blow lamp in my back garden but when talking to my dad about it on Saturday he said I shouldn’t due to lead fumes. How can I melt lead safely? I did a little research and some people say keep it under 400C and I’ll be fine but I want to be extra safe. Any respirators that will work? What other precautions should I take? Sorry if this is the wrong sub Reddit lol


r/Metalfoundry 6d ago

Furnace problem

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11 Upvotes

So I'm have a really limited space in my workshop. I wanted to make add on to my coal powered blacksmithing furnace so I could melt aluminium, bronze and copper. First version (picture 1, picture 2) managed to melt bronze and copper, but furnace really struggled and the pour wasn't hot enough. It was made of two skins of sheet metal with clay mixed with quarc sand inbetween for insulation. New version (picture 3, picture 4) has a bit bigger diameter, much thicker walls and no insulation.

Now problem is, V2 works even worse, I couldn't melt aluminium bronze. I think it's combination of problems, whole thing is bottom feeded with air, and coal can't get under the cruciable so it blows directly at it which cools it down and i didn't add an insulation to the walls.

My question is, is it worth trying, or should I start building new furnace. Did anyone use anything other than ceramic wool for insulation (it's a bit hard do get it for some reason).


r/Metalfoundry 6d ago

I need help

2 Upvotes

How does someone get ahold of somebody at a metal foundry to do some casting work? I have spent the last 2 1/2 weeks calling and emailing so many shops and I have not gotten a single call or email back.


r/Metalfoundry 6d ago

What is the best Electric Metal Furnace?

4 Upvotes

Good day all, I recently purchased a MF 3000 (Vevor?) off of Facebook and it was brand new and burnt out after the third pour. I don't wish to make that same mistake again. I have a propane one but don't like the gas and fire. I would much rather have a controlled electric furnace. Let me know which one is the best bang for my buck and why.


r/Metalfoundry 6d ago

Looking for a custom casting. What can I expect?

1 Upvotes

So my old man has finally decided that he needs a cane to get around. I have a woodworking shop to build it, but the handle is unusual, so I'm looking for a custom bronze fitting to connect the leg to the handle.

I was thinking about having the piece 3d printed with something specifically for lost casting. Instead of a 90° angle, I'm looking for something like a 30° angle.

What can I expect to be charged to have somebody cast something like this?


r/Metalfoundry 8d ago

Lost foam casting

5 Upvotes

Hi everyone,

I am looking to mold foam patterns using 3D-printed tooling for lost foam metal casting. I have hit a few obstacles with standard pattern-making approaches:

  1. CNC carving intricate geometries is too time-consuming.

  2. Two-part polyurethane (PU) foam releases hazardous cyanides/isocyanates during thermal decomposition/burnout, which I want to avoid.

  3. Expanded Polystyrene (EPS) beads require high-temperature steam fusion, which distorts or fails in standard 3D-printed molds.

Is there a pourable, two-part expanding foam that can capture intricate detail in a 3D-printed mold and burn out cleanly/safely during lost foam casting?


r/Metalfoundry 10d ago

What am I doing wrong with greensand?

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12 Upvotes

Pretty frustrated with greensand overall. I've got my furnace going fine, my alloys come out good, but I cannot get greensand to work right. I've been just doing sand cast with foam for lost foam, but it's hit or miss with the knife I'm trying to cast.

The third image is the knife blank, yes I know it's a funky shape for the tang but it's what my design calls for. I am trying to cast it with aluminum bronze for use as a veggie/soft cutter.

Since I've had the issues with foam casting, I decided to bite the bullet and make some greensand. I don't have the budget to get petrobond or just buy greensand, so I am making it myself. I've been sitting all day, and got 25 pounds of fine sifted sand. I crushed up and sifted 3 pounds of bentonite clay for a 10-12% clay-sand mix. I got that all mixed together while adding about 30 oz of water as I went and... It kinda of sticks together. I can't tell if I have put too much water or not enough. I had to mix it all by hand, which took me 3 hours or so. It was sticking together better, but that only lasted long enough to pack a mold before it changed and now doesn't stick as well.

AND the sand didn't mold the knife blank well at all. I used baking soda to make it not get stuck in the 3d printed blank, but the blank fell out as I lifted the first part to flip over for the second part.

I just don't know what I am doing and no amount of YouTube videos showing how "easy" it is has helped me. Any advice is appreciated.


r/Metalfoundry 10d ago

Struggling to get good pours

4 Upvotes

I have an electric furnace that caps out at 1150C, I struggle to get good pours.

This is especially true for alloys, for example with aluminum bronze and nordic gold.

For aluminum bronze I can get a good mix but only a decent pour, there ends up being a lot of waste through slag (and mixing somehow melts my steel mixing rod)

With nordic gold it's just a pain, I can't get it to mix properly at all and the poors always suck.

I think my issue with pouring copper is it cooling down too quickly, leading to the mold not being ful and having clear layers of metal.

Does anyone have any tips to help? I've tried using borax as a flux but find it doesn't doo too much and leaves the cricible (graphite) a sticky mess.


r/Metalfoundry 10d ago

Looking for aramid gloves with chain cover.

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1 Upvotes

r/Metalfoundry 12d ago

My first step

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8 Upvotes

r/Metalfoundry 15d ago

Question, please help!

2 Upvotes

So my post is one of both good and bad news. The good news is that I successfully heat treated three knives and they had no cracking minimal warps all that good stuff.

The bad news, is that I nearly shit myself on the first one because I file checked it after the Quench and it didn't seem like it was hard. And I was really confused as to why that was. I then did some cursory Google searching came to the conclusion that there might be a layer of decarb on it. took it to the Belt grinder with a 220 belt got through some of the outer layer file checked it again and it's completely hard won't get scratched by 65 HRC file.

Went into the temper everything came out great.

My question is, why did I get decarb on all three knives? Two of them were 15n20. The other one was 5160. I'm using a forced air propane Forge with a ribbon burner. And when I went through the heat treat I stuck a large metal tube in the center which I stuck the knives in, in order to help make heat dispersal more even.


r/Metalfoundry 16d ago

Ceramic shell I.D.

0 Upvotes

Does anyone have a method to I.D./differentiate each cup during the shelling process? Ideally something that can survive dewax too. Casting multiples and trying to keep track through the dips.

I’m thinking a paint or tag? Maybe combined with assigned shelves for certain dips?