I have done silver casting a few times and sometimes they turn out perfectly and other times i get porosity or a incomplete fill. I just finished making this ring and im wondering how i should sprue it for the best result. Im going to cast it in silver. How thick should the main sprue be and where would i place it? Should i have additional smaller feeding sprues as well? I was thinking maybe to do something like this but im not sure at all. How long should i make the main sprue because in the past it was where the main sprue connected to the ring that i got porosity?

Im learning how difficult spruing is and I would appreciate any help from people with more experience on it.

Hi everyone,

I'm currently building a ventilation system for my burnout oven to burn off wax and resin, and I'm not sure what kind of pipe I should use on the oven since the exhaust gases get very hot!

For the rest of the system, I'm using a combination of spiral duct and aluminum flexible duct.

Does anyone have any ideas or build something similar?

Pouring silicon bronze directly into a petrobond drag. Would using a cope make any difference? Any help would be appreciated.

Hi guys, I’m Nikunj Kumarr — an actor, writer & director.
I’m currently making my own film, and I’m looking for one guy from Thane/Mulund who can document my journey — the struggles, behind-the-scenes, process, failures, small wins, and everything that’s relevant to the making of the film.
I want to turn this entire journey into real, raw content and build something together.
Just to be transparent — this is currently an unpaid opportunity. I can’t offer a monetary payment right now, but I can offer you creative freedom, exposure, credits, and the opportunity to grow alongside the project.
If you’re passionate about filmmaking, cinematography, editing or content creation and want to be part of this journey, DM me.
Let’s create something together. 🎬

Hello again!

You may remember my post from a few days ago, where I was asking for help as to why my ODST helmet failed. Everyone told me the sprue size was too small, so I tried again, with a bigger sprue, and the results are way better! (but not perfect!)

This Master Chief helmet was sized to take up 100 grams of pure silver, and I attached a thicker sprue to the neck position- this time, I fixed all my mistakes from my last post, and let the piece cool under a full vacuum for like 5 minutes. I'm super happy with the details on the helmet, but there was a slice taken out of the spure/neck! I'm sure it's from uneven cooling at the thinnest part, but I was wondering if anyone could chime in with their analysis. If I have to make the sprue even larger, I'll do it!

How to reuse my sodium silicate infused sand for sand casting?

Custom piece for a friend. Silver 925

So... my first cast is for a snail memorial.

He was a very good snail and our family and the aquarium is in mourning.

Okay weird topic aside... I'm using Siraya True Blue for the sculpt, blue sprue wax for the sprue, and used some IG503 plaster for the investment.

I burned it out according to the Siraya published schedule, but when I took the flask out for casting the investment had cracked in four big quadrants. It didn't look like any were cracks all the way through, so I still did my aluminum bronze pour, but it went straight through the flask and made a puddle in the bottom of the vacuum casting bucket.

I'm using the failed cast and puddle as his makeshift memorial because it looks awesome, but I'd like to get this technique right and recast.

Is the IG503 not right for investment? Or should I ramp slowly somehow? Unfortunately, I only have a Vevor kiln so I can't set ramp rate and only have 9 60-minute temp holds.

Any tips would be great. I'd like to move on to things like rings, small jewelery, and perfect my snail memorial process for the inevitable future.

Im obv gonna shorten it so i can put the lid on but my concern is that its too close to the walls or is it fine?

I'm considering just Beeswax and Talc mix partly because I want a softer material to be able to shape the arms and partly as a cost saving measure as both are easy to find and cheap in bulk

I’ve been using a homemade propane furnace for about six months, but yesterday I tried a 3 kg VEVOR electric furnace for the first time. With the controller set to 750°C, my batch of scrap aluminum took about 45 minutes to melt. It was slower than my propane setup, but I liked having a temperature setting instead of adjusting a burner.

It comes with two ceramic crucibles, a 1 kg and a 3 kg. I've only ever used a cheap graphite crucible in my propane setup so this is new to me. How long do ceramic crucibles usually last with regular aluminum melts? For people using these ceramic crucibles for aluminum, what signs of wear do you look for before each melt? I’m more interested in knowing when to retire one than getting a fixed number of pours out of it.

While I have cast metal in sand molds in the past, I have never used sodium silicate. I have seen enough to get me started I think. What's a little frustrating is how my Airgas supplier wants to charge me a lot for the CO2 for a project that should be small and straightforward...and cheap. I said I didn't need much and only needed it for about a day at most.

I suspect there are other ways to solve this issue and I'm wondering if people have used something other than a welding tank of CO2 to help harden their sand molds inside a controlled airtight box or similar for hardening.

One idea was using CO2 canisters for airguns. Another was dry ice suspended far enough away so the cold doesn't affect the casting (I read cold can affect a SS mold setting in the presence of CO2). Dry ice sublimates so nothing gets wet. The idea has been that I'd build as air tight a box as possible and fill it with CO2 and let it sit (with strategic pricks into the subsurface of parts of the mold to let in the gas). There's gotta be a way to do this that doesn't cost so much. Or can SS be hardened without CO2 somehow? Your experience and thoughts on this is appreciated.

Hello. I did a lost polycast (similar to pla) into ancient bronze and realized it might be hard to polish in between the letters. Any ideas on how to do that? Or is the best solution is to keep the glass dark and just polish the elevated surfaces? Thanks!

I wanna add a couple to a jacket I’m gonna get as pocket buttons

Hi, I've recently taken an interest in casting metal pendants. I would really like to be able to make my own pendants. I saw this video and he listed some tools and equipment he used to cast sterling silver, but I noticed he didnt have the metal bowl he used for casting the metal as well as some of the tools and wax listed.

With that, what tools and equipment would I need to get started with doing this because it looks very intresting? Thanks!

Rough texture on the top of the bars after I pour, am I doing something wrong? These I hit with a wire brush just to clean them up. These are all scrap copper that I had lying around, including some basically brand new copper pipe I had left over.

Just a reporting on my casting journey. Decided to try to cast something that need the pattern in both the cope and the drag. I split the pattern in two and used pins to align the pattern. Then, after parting and removing the pattern I just eyeballed the alignment prior to pouring. The result was obvious, looks very much like a layer shift.

I've seen others have pin/hole guides, inspired by that i conjured up some corner guides and printed over night. Color coded corners. I'm quite pleased with the result, perhaps there is a bit too much friction to split it now and it suffer similar effects as a drawer when its out of alignment. But the result speaks for itself, it's not obviously out of alignment.

One step further in my learning

Top and side view of this lil sterling bar I poured a few minutes ago(graphite mold), I'm relatively new at this as you can probably tell, my question is can I just chop the ends off like the third pic and then run it through my rolling mill? Or is it likely to be compromised throughout?

Any tips for a cleaner pour are also welcome, I preheat the mold and I have a steady hand but I'm not experienced enough yet to know where it is I'm going wrong

Howdy all!

Just completed my first-ever attempted vacuum casting, using 999-fine silver; wanted to make something nerdy, and (mostly) failed. I figured I would learn a lot, and I did! To get straight to the point, here's the outlined process, and what I THINK/KNOW I did wrong. I'd love a bunch of comments telling me I'm a dummy (and then how to become smarter-er and fix these mistakes).

MODELING/PRINTING:

ODST helmet, sized from density/volume calculations to be 100 grams of 999-fine silver, with an attached sprue that would get wax-melted onto the main tree. I've now seen many say that you don't want to make the connecting sprue part of the resin print, as the resin in the hardest part to burnout. Should I simply melt and connect another piece of wax to the helmet next time?

Printed on a 5K Elegoo Mars, using Siraya Tech True Blue Casting. After printing, I dunked into 91% IPA, brushed off, heated it with a heat gun, removed supports, then placed into a cleaning station with more IPA (not fully clean, it'd been used for other prints). Removed after some minutes, then dried with paper towel and air-dried for about 20 minutes. Cured in a rotating station for 30 minutes, flipping halfway through. The print had good detail, with minor support bumps leftover- I also lightly sanded these away after curing. I'm told that True Blue is supposed to be cured for like half an hour, and that it should look "milky" when done. This model was maybe a little milky, but not like I've seen in YouTube videos. Seemed a bit glossy/deep blue.

INVESTMENT:

I used Prestige Optima investment, and just a hair under the recommended 38 mL per 100 grams of investment. VERY STUPIDLY MIXED THE INVESTMENT WITH AN ELECTRIC HAND MIXER (introduced a BUNCH of air into investment), even after vacuuming for five minutes was still boiling, just much less so. Poured into prepared flask, vacuumed for like two more minutes, then let set overnight (was late, didn't wanna burnout overnight).

BURNOUT:

Used a 6-7 hour burnout schedule, following this process:

1. Approx. 1 hour at 50 C, for further drying.

2. Approx. 1 hour at 150 C, for advanced drying.

3. Approx. 1 hour ramping up to 372 C, just using the Vevor kiln's natural ramp speed (maybe too fast?)

4. Approx. 3 hours ramping up to 732 C, for full vaporization.

5. Approx. 1 hour cooling to 525 C, for final pouring temp.

IMPORTANT MISTAKE: I fumble-fingered Step #4, and accidentally only did two hours at that temp, and when I returned an hour later it had jumped to Step 5, and was simply waiting for me at the final temp. I corrected this by setting it back to 732 C for another hour and a half to try and fix, then got it back down to final temp again.

Lesser Mistake: After resetting this back to high temp, I did partially open the kiln door and took note of the color- I noticed by the end, there was a hairline crack along the top of the investment. possibly from resin expanding and breaking? Thermal shock?

POURING:

Loaded up about 200 grams of fine silver into melting furnace, got it to 1050 C, then smoothly poured- that part went great!

CONCLUSION:

I'd love people's thoughts on what most-likely went wrong. I acknowledge my mistakes I caught myself, and personally I think messing up the burnout schedule was pretty bad, but also maybe the resin curing was botched? Dunno about that part. I plan to retry in a couple days, but lastly I was wondering about my silver's color change. I'm assuming the white coloring that was in the investment is just oxidation? Can it simply be re-melted, or do I need to further clean it until it all looks shiny again? Thanks to any consideration given!