Making sodium silicate cores
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- Опубліковано 28 сер 2024
- Thought I'd take a minute to show how I've been making sodium silicate cores for my molded parts that need a hollow space in them. I use easy to find and purchase materials. All of it came from a home improvement store or the grocery store
Thank you yet again. Just getting in to Sodium silicate and the tip with baking soda and vinegar is a great one. going to go and try it now!
Hope it works out for you, Good luck :-D
Thank you I have learned something new for future projects..
Hola mi nombre es Christian soy de argentina y estoy muy agradecido por su video, no entiendo mucho el ingles pero he podido darme cuenta como resolvio el problema de no tener una botella de co2, tengo el mismo problema y usted me dado una excelente solución, muy agradecido por su video. Saludos seré su suscriptor nuevo ! 😊
Lamento que tengas que trabajar tan duro para los videos en inglés. Ojalá pudiera traducirlos pero es demasiado caro. Gracias por trabajar para verlos. Me alegra que la solución te haya ayudado. Puedes dejar el núcleo en el aire durante unos días y también se endurecerá. Simplemente lleva mucho tiempo.
Hi, great video, thanks!
You can also cure with a tea light candle instead. Just cover the container with a metal sheet, the candle inside will die out eventually, and you are left with co2 and water vapor, plus additional heat also should help.
Cool tip, thanks
I was born in the early 50s & I have lived a pretty full & industrious life, but I have never heard of this sodium silicate / water glass before.
I am blown away at the many ways it can be used & how to set it.
Amazing
I was born in the waning days of the 50's and still find one of life's greatest joys is learning something new. 😄 Thanks for letting me know.
This video will help me for my dissertation! Thanks, sir!
On what not to do? 😆😆 FWIW I typically put way too much sodium silicate in the cores resulting in all sorts of gas being created during the pour. At this point in my life, I won't do another sodium silicate core until I have a bottle of CO2 available to harden it.
@@swdweeb somethimes knowing what not to do gives far more insight. It will allow me to get some shit done the handymansway ;) I hope you get it done! I saw someone use breathing to create CO2 for hardening... So, chin up and thanks!
Cheers and thanks.
@@emel60 I have a project in mind that will use hardened green sand as a core. I really have had any casting ideas that required cores over teh last couple of years so I haven't invested a lot of time/money into the process.
I've heard that if you just let sodium silicate infused sand sit out in the room, it will use ambient CO2 to harden. It might take quite a while but it will harden.
@@swdweeb either way, I will soon try to cast, so I can test thst one as well. It costs me nothing but the time it takes me to remind myself about it.
Cheers,
Wow! Awesome solve on the CO2. Never would of thought of that. Nice one!
I'm a thinker, I am ;-)
I saw it some place else but don't remember where so i couldn't give credit where credit was due.
Sodium silicate is what I use to line my forge and foundry. I sprayed it over the refractory wool. They call it water glass at the pottery supply websites. I will bet you that the cement floor sealer is a good deal cheaper than what they charge for the water glass and it is the same thing in a much smaller bottle. Learn something new every day. That will be the last time I buy it from them... Thanks for the information... On the forge walls, I just let it dry and fire up the forge to cure it, seems to work so far. It will take a ton of heat and stay put... Be well...
Good to know on lining refactory wool. Thanks
Looking forward to the hammer cast! Thanks again for sharing your findings. Very useful information.
Thanks, I'm looking forward to it too. I've just got to get one that works ;-)
I might end up doing a "bonus" video in the next couple of days that shows something I learned about feeders and gates. Pretty interesting stuff.
Nice core, good job! 15 minutes on low in the toaster oven will cure sodium silicate cores too. I get mine in the form of wood stove gasket cement because I couldn't find it up here in Canada as cement floor sealer. Some car radiator patch fluilds are SS-based too, I couldn't get it to work for me but others have claimed to.
I looked for the radiator patch and couldn't find it in any of the local stores. It might have been there but I didn't see it. I've put them in the toaster oven too after they've hardened enough to handle. I don't know if it matters, but I'd just as soon drive off any moisture I can before pouring metal on it.
swdweeb the rad patch I tried was called "liquid copper", on the shelf at the Canadian Tire. The package did mention SS but like I said I could not get it to cure. Anyhow, the floor sealer seems to work well and that's a big bottle, so I guess you're all set! When I make cores ahead of time, I always put them back in the oven for a bit right before making a mold just to make sure they're very dry too. Because cores do produce some gas when they heat up and are trapped inside the casting when that's happening, I also vent my cores generously with a thick wire or dowel of some kind and vent the ends of the core prints through the cope as well. Making the cores a little bit shorter than the prints ensures the cores don't block the prints' vents.
Seems like I saw that. I'll have to look again... in ten years when I run out of the industrial sized jug that I bought ;-)
Awesome, I'm getting into the art of mold making myself currently and videos like these are really helpful. Say, do you think it could also work to put a glass of sparkling water into the container? Afaik the bubbles from the carbonation are pure carbon dioxide, so it would slowly build up in there. Alternatively there are these tanks for soda machines, but no idea how easy it is to get it out without it exploding into your face.
I think the tanks are really the way to do. Any welding supply place with have them. If I ever get back into sodium silicate cores that's the way I'll go. You can harden them by just letting set out. They'll absorb carbon dioxide slowly from the air. No need to waste a good soda :-D
Great tip thanks! Love your video's. I look forward to yours, big dog, Paul's, county line, chandler, black bear and others. You seem to use the same channels I do😀 thanks again. Anthony Kent
yeah, birds of a feather they say... I just need to figure out a way to get more of their subs to sub here ;-D
swdweeb just keep the content coming along. Make a heavier weight hammer in brass or something like that. A dead blow hammer that is, and send it to Paul, saying "hey beat that bro!!" Combine the viewing for both of you. Send chandler one as his was workable only just, it will save him some time doing one as he has his hands full!! Remember that I got to you from Paul to Paul from big dog from big dog to loads of other casters and Smith's. Anyway would love to see you make for other UA-cam channels. All the best Anthony Kent
Hang in there, your wish just might come true;-)
Great video. A few observations:
1. I've been making a sand core cylinder 5" long, 1/2" in diameter. The mix is about 1/2 tsp waterglass to 1 oz sand. Mixed well, it is relatively dry. I cure the core in the core box in a toaster oven for 75 minutes at 265 degrees F.
2. I don't know whether it is the hard, rammed pack or the waterglass adhesive cured in an oven (or maybe both), but the core always sticks to the wood mold. Paint didn't help. Oil didn't help. Talc didn't help. The core often breaks when removed from the mold, sometimes at a crack, more often at a hidden weakness. To reduce stress on the core during removal, I made a four-piece wood core box held together with long screws. A 1/4" cove cutter on the router table cut the center hole, one quadrant at a time. After curing, and with the screws removed, the box opens one or two parts at a time. With less surface area to grip, the intact core can usually be "rolled" from the 4th quadrant.
3. The cured and cooled sand core is stiff and hard but very brittle. Exposed to intense heat and a stream of molten metal during casting, however, the core can flex or deform substantially, even float, inside the mold and so ruin the casting.
4. Prolonged casting heat degrades cured waterglass. It loses its binding ability. When water cools a casting, the core becomes wet sand. (On the other hand, a packed sand/waterglass mixture is the floor of my furnace, and it remains intact after many firings and direct and prolonged exposure to a propane flame.)
Ideas:
1. For wood core boxes, use a hardwood, something less likely to grip the packed sand.
2. Design the casting mold to channel the stream of hot metal around the sand core, NOT directly against the sand core. Put no unnecessary force against it.
3. Don't paint a core box used in an oven. The paint melts and makes a sticky mess.
4. I will try opening the core box and exposing the uncured pack to CO2.
I'm still getting many failures making and using this sand core.
Thank you very much. This has given me many challenging, frustrating, and interesting hours.
Sorry I've been slow to reply.
I made a waterglass core about a month ago. I used a two-piece printed pattern. Rather than making it one core, I made it two "half" cores that could simply be placed together. It cured nicely in room temperature. (Can't put printed parts in the oven, they warp all over the place) The core halves did leak some but it was livable.
I also mixed the sand to waterglass at a much drier ratio than I did in the video. I think that helped with it not being so sticky.
CO2 seems to be the key. I haven't ever invested in a bottle or way to inject the core. If I did more cores I would probably break down and spend the money. Heck I spent $20 on four gallons of gas today, I should probably be able to buy a bottle of CO2
@@swdweeb Thank you for your comment. I probably don't have enough years left to learn 3D printing, so I make my patterns and core boxes the hard way. I tried packing a core with sand/waterglass and exposing it to the air, but the damp sand broke and crumbled every time I opened the wood box. I bought a small bike tire inflator that uses 16 oz. CO2 cartridges and applied it against the open end of the packed core box. It worked somewhat, penetrating and hardening about half the 5" long core. I could apply it to both ends, but the method gets expensive, especially with such high breakage. I tried additional waterglass, but more than 1 tsp per oz. of sand in a rammed, baked core box shows why waterglass sells as an adhesive.
With a suggestion from my wife, God bless her, I had a recent success. I made a new core box using scrap treated pine and rubbed a heavy layer of powdered graphite on the core surface to make it smooth and slippery. I lightly rammed a mixture of one scant tsp waterglass in one ounce sand into the box and baked it two hours at 250 degrees F. After it cooled, it went into the refrigerator overnight. This morning, the cold core box opened easily, and the core almost fell out, hard, intact, and strong, almost as if I knew what I was doing. It's difficult to take lessons from my experiments because they usually apply several variables, in this case, a new and undamaged core box, the graphite rub, a light ram, and the overnight chilling, but it worked. Glory, Hallelujah! We'll see if it's repeatable. Thanks again.
@@fredwild190 I think from what I've seen and minimally experienced, a light ramming is what we need. Ramming too hard just presses it tightly against the box. Lubricant is good. I might have used some parting compound in mine now that you mention it. Cold seems good too as I expect it helped the core shrink and pull away a bit.
Of course listening to your wife is probably the most important lesson. 😄
Baking soda and vinegar works great. Another way to generate CO2 would be a glowing coal put in the container with the wet core. Better use a metal container, and put the coal on something reasonably insulating (I use a piece of scrap kaowool left over from my furnace build)
Yeah, that would probably help dry it to. I've stuck these things in the oven at 200F for a short time just to help them along after they've hardened.
Thanks
Just found you because I'm having the exact same problem (don't have a co2 bottle), I previously tried a few of those mini cycling tyre inflator bottles but they were too fiddly and ran out almost immediately. I'm hoping to make a decent core with your method, for an axe I'm trying to cast (I'll put a link to this vid in my video description) I'll let you know how it goes! Thank you so much again - right i'm off to the shed to try this out! +1sub (edit - i'm a field goal kind of guy - sometimes you have to be :)
Good luck! Definitely let me know who it turns out.
I’m casting an Al Bronze hammer too this weekend. Didn’t realize I needed to bond the core but that makes sense so it doesn’t fall apart
If you can pull it off without some sort of binding agent, you'll be my hero. ;-) Good luck with it. Make sure you give it big enough feeders
Thanks, this was another great informative video. I have an idea I'm going to experiment with in making cores and will post a video if it succeeds.
Cool. I need to make some greensand cores as well. That is entirely possible and much less hassle than the sodium silicate which is tough to do without carbon dioxide floating around
@@swdweeb have you had success with greensand cores?
@@JasonSipe16 Well, how about I give a qualified yes answer to that. I've made greensand cores, they have worked well. I just haven't done very many of them. They take longer than sodium silicate cores in that I let them dry out and harden before I use them. For me just being a guy in his garage doing a really small number of castings that's not a big deal. If I were running production, I'd break down and buy a bottle of CO2.
I appreciate your replies. The older I get, the more willing I am to learn from other's trials and errors. ;)
@@JasonSipe16 I couldn't agree more. Its too bad that when we're young and know it all we miss out on learning from others. 😄
Was just on home depots site to order some sodium silicate and I was reading reviews and saw you left one just thought it was kinda funny
Yeah, I'm a giver ;-)
I've still got about .99 gallons of that stuff. I'm using it in my video this week. Maybe about 2 teaspoons worth ;-)
Bigstackd sent me. Awesome channel!!
Thanks for letting me know.. He's a good man, despite the clown mask :-D
First u ve to use talc or any micro powder&coat d box b4 to apply d wet sand2avoid stick, u can use concentrated water sugar, little heat can replace co2 n both
Tnx sir
You're welcome
That cool, I did'nt know their was an OTC chem that had Sodium Silicate in it. That saves me time and money making it from silica gel and Sodium hydroxide drain cleaner.
I just recently talked to luckgen1001 and he uses fiberglass resin and sand for his cores. He tells me that the resin decomposes during casting better than the sodium silicate and is much easier to remove from the part. I'm going to have to give that a try as well.
What I use sand/sodium silicate for is to make refractory material to line a furnace, its not the best but its cheap and holds up much better than plaster and sand. Also use the left over to make bricks that are great for putting bullion molds and melting dishes on.
Then resin isnt for you. ;-) I had only recently heard of people using sodium silicate to line a furnace.
I got into an argument with someone just last night that said plaster and sand works just fine. Mind you they've never build a furnace, run a furnace or cast anything but they were expert on the lining of a furnace. I just shook my head and walked away
Plaster and sand is doable, but it breaks down pretty quickly. I just have a simple paint can furnace, but its lined with the sand/ sodium silicate, stuff works pretty good. You think that guy was a know it all, try joining the MPSM (monoprice select mini 3D printer) owners FB group. LOL! I got into it on that bc some guy was moving his bed back and forth quickly and the screen was briefly lighting up bc the motors act like generators. Tons of ppl saying he's gonna fry his board. I may only have an associates in EET, but no way is that gonna fry anything.
Yeah there are people like that everywhere. I'm old enough to realize that unless I've actually got experience in something I'm not going to get dogmatic about it. One of the reasons I stay off FB. Way too many opinions expressed as fact.
I will definitely use this method if I need to make a core, but I would wonder if suspending dry ice over the core would be effective. I am to understand that dry ice is solid Co2 and as it sublimates, it should create a co2 bath. Keep up the good work!
If you have dry ice, I expect that should work just fine. In terms of what dry ice is, your understanding is the same as mine. I have ready access to the vinegar and baking soda so that's what I used.
I read somewhere that you can use Sodium Silicate to "glue" or seal kaowool for building a foundry. Any thoughts on this?
That, I knoweth not. I know that the core gets really hard when it cooks with the metal around it. So, it doesn't appear to break down under that sort of heat but I have no idea how it reacts to a direct flame
It's likely doable but probably not the best. When it hardens by absorbing CO2 from the air it turns into a mix of silicon dioxide and sodium carbonate, which is essentially soda glass. That would likely begin to melt around the melting point of copper. A short exposure to high heat like in a core for casting is OK, but I wouldn't guarantee it can take heat for a prolonged time. I would recommend a refractory compound like satanite instead. Satanite works great in my furnace.
The idea behind using sodium silicate is that it is hard enough to form a core but it then breaks down during the pour from the heat transfer from the metal. Once your pour is completed you can then break out the core often with the help of a water soaking. So for your intended use it would not make for a permanent solution due to the breakdown under high and repeated heatings.
subscribed
im enjoying your vids
thanks
Thanks for both of those :-D
Loved this! My only question is how strong is the resulting casting of sand? Is it strong enough that it wouldn't break easily? Thank you so much!
Are you asking how strong is the core? It's pretty hard, you'd have to hit pretty hard to break it. Normal handling wouldn't do anything to it.
@@swdweeb thanks for the quick reponse :) that’s great to know! I just did an experiment very similar to yours but the core is set in a silicone mold - would that deter the curing of the core? My core is also a little slimier, is that a bad thing? Thanks so much!
@@gerickking1020 Ok, let me get this out there right now... I'm far from being an expert in cores 😄
I can tell you what I've heard from people that are more expert than me. Your core should dry hard and not have "slime" on it. hat may be because of the silicone not allowing the sodium silicate to dry. It could be because you used too much sodium silicate as well. I used way too much in this video. I say that and I cant be of much help with the proper ratio of sand to sodium silicate. It's probably out there on the web somewhere.
The problem with too much sodium silicate in the core is that it releases gas when the metal hits it. If you don't properly vent the core it will cause deformities in the casting. I've seen that happen. More sodium silicate = more gas.
When I need to do another core I'll be looking for a CO2 bottle so that I can inject the core with that to harden it. What I did in the vide works, but it takes a long time. From what I've seen this stuff hardens almost immediately when hit with pure CO2.
Anyway, I would say that slimey isn't a good or normal thing.
Have you tried making a mold made from sodium silicate and sand?
I’m wanting to try packing some of this around a 3D printed resin model (just the face) that has fine detail and place a plate with a tube in it to act as a pour spout/tube for the needed pressure.
I've only done cores with sodium silicate sand. From what I understand, professional foundries do what you're suggesting. They certainly do it with flourine-based resin sand.
@@swdweeb Thanks.
Settle for a field goal (settling for what you can get short of your goal). Apply that thinking to gas in the car. Pass on buying a half a tank just because you don't have the funds for a full tank? You risk running out completely before your next payday.
@swdweeb so it dose say water glass on the label I know what it is people at the big box store do not know that tho
Yeah, they're not experts in much
I don't understand why you need to use CO2 in the first place. You don't use CO2 to dry it when applying it to cement floors and those dry just fine in less than 30 minutes.
Most people have far more efficient ways of delivering CO2 to the sodium silicate than what I did. They do it so the cores harden almost instantaneously. Part of the problem with cores, or molds as well, is they are far thicker than the layer that gets spread on a floor. The sodium silicate at the center may take hours or days to harden due to the lack of carbon dioxide in the thicker sections.
@@swdweeb thank you. That was helpful info. Just started watching, and by no means watching them in order. Your videos are informative and interesting. I like to see the fails ( one reason I watch Pauls garage) so that I can see what I might expect to happen so that I won't be as surprised if it happens to me. (far future)
@@StonerSmurfin I'm glad it helped. Don't hesitate to ask if you have questions
So... I made my second NaSiO core, and it hardened up nicely in a ziploc purged with CO2. Got hot, even. And the next morning, I picked it up and it fell apart in my hand. My first core is still hard as a rock weeks later? Ideas?
Hi Eugene, sorry I missed this. I'm a terrible person to ask as I havent made a core for over a year and like you I havent been very consistent about it. I'll show your comment to a couple of others and see if they have any ideas.
Just use a CO2 extinguisher. Its cheap to buy and refill
Good idea, just mark it as partly used so that you don't try to put out an emergency fire with it.
Great method! Turned out well!
If you revisit this experiment, will you try dry-ice?
Thanx Buddy! :D
Hadn't thought of dry ice. I expect that it will work pretty well. I've been battling a core right now and I'm about ready to invest in a CO2 canister.
I was thinking soda.
Carbonated water maybe?
I actually looked at those canisters you can get to refill a carbonated drink maker type machine last night. Certainly a cheaper initial expense, but I expect more expensive long-term. We'll have to see. The core I made for this Friday's video was a pain in the butt. I"m not looking forward to do anymore of them in the near future. I need to forget how much fun this one was first ;-)
Cool! :D
Another place to check into CO2 canisters would be any place that sells paintball supplies. I know my local Army Surplus can refill them. I think it that would be cheaper (or the same price) because it doesn't have to be "food grade". You might also check your local fire department. Some fire departments can refill CO2 fire extinguishers, so that might be an option.
However, it would not really surprise me in this throw-away society that buying a new extinguisher would be the cheapest method overall...
What about kick a three points?
that is a field goal
Very fascinating I really like the stuff that you do and on a side note it's a good alternative from all the political stuff on UA-cam
Even my comment about standing up that made several people mad? Learned my lesson on that one. ;-)
Thanks for the comment, I appreciate it.
Good info. And make them stand!
Early returns on this video show I must have struck a nerve with that comment. I usually don't start with three dislikes in the first 40 views. ;-)
swdweeb that was exactly what I was thinking!
Great now I need a 3D printer. LOL
Nah... just add some stepper motors to your mill. ;-)
1:42. 3:20
??
Liked the comment about football "stand-up ". We must be of the same mold.
What, you're young, intelligent, and good looking too?? :-D
swdweeb I think I am older than you. 64.
So you are young ;-) It's all in the mind... and the sore back and knees
swdweeb some days I feel a lot older than that. Have a great Saturday.
so far so good :-)
Dude, your voice sounds like Trump. Great video by the way.
What??? I developed a New York accent and nobody told me??
Thanks!