Thanks for your comment Colonel. Do have a look at the last video of this series (link in the description), you'll find my final take of all this. I hope it helps.
I’m with the colonel. This video is amazing and your no nonsense, no frills straightforwards diy approach is amazing. Also your skill in executing the task at hand and ability to explain what you’re doing and why you’re doing it is next level. Thanks for this video, and the time you took to make it. It’s perfect in every way. About to order the refractory cement and wait for it in the mail like it’s Christmas. I have a knob that’s missing on a table saw from 1933, and it’s gonna be awesome replicating the twin of the missing knob to make the saw that much closer to being complete, with all original parts, down to the nuts and bolts.
Many thanks for your comment Edward. It's a pleasure to hear viewers are getting something out of my videos. I'll be posting a video in the following hours about risks and hazards in foundry. Stay tuned.
@@jessemartinez6781 The truth is, the privilege is mine, as in many cases I'm only giving back knowledge I received for free when I was young and needed a hand.
Rod, The process should be viable for simple shapes, Stone moulds were used during the middle ages for small bronze parts and way before that for things like arrowheads and spear tips. It was a fairly soft stone - soapstone or soft sand stone I suspect, something that could be easily carved. I am dubious of its applicability to larger work as the contraction of the castings will lock them into the die and while some form of ejection mechanism is entirely possible each time a casting s removed some of the relatively brittle die will rub off - the die will thus be a fairly short life affair. The aluminium dies that I occasionally use proved to be total disasters if the part being cast could shrink onto the die in anyway, The use of wood for the master has problems as even if well varnished and greased it will possibly /probably swell when it gets wet and lock into the cast block. Making it, as you found, impossible to remove without damage to one or both. Quite vicious vibration during placement of the refractory may help get rid of those bubbles - an out of balance motor under a spring mounted table, but you need to have strong mould boxes. Good luck... Martin
Wow! You can't make someone happier reading such a detailed and knowledgeable analysis of my attempts and the options. In your words you show you care for other people and for this art, and that is very valuable. Many thanks. I have been considering the possibility of creating a bronze die, to pour my aluminium into, but I hadn't thought that the cast contracts when cooling. A locked cast would be just too bad, and considering the complexity of my model that's what probably would happen. And if we add to that, that some parts of the figure might not have a perfect angle for extraction, a locked cast is the most probable situation with a metal die if I can't fine tune every angle of the figure. Maybe an impossible task. BTW, I would like to send you a virtual present in recognition of your friendship: a nice pair of good gloves. Take care of those hands.
Hello Kyril. This video is part of a series of failures in trying to make a permanent mold for a complex figure. In the final video I am able to produce a successful mold, but only workable with a simple figure: ua-cam.com/video/7U38teByJkQ/v-deo.html
I'm looking for a material for one time cast for silver, lost wax, that doesn't need to be pressurized and either doesn't need to be baked or can be done in an oven,
Hi Hex. If you refer to the mold, a mixture of plaster and silica sand can be heated in an oven for drying and getting the wax out, and although nobody forces you to use pressure (a vaccum) the surface will end up with bubbles. If you refer to silver, there is no way you can cast silver in a kitchen oven, as the temperature rarely gets above 200ºC.
If you cover the wood with gas or light motor oil. It helps the concrete from sticking. Remove when concrete is slightly hard. And for air pockets we just tap forms with a hammer. Local 528 adamant mason hope that helped some?
Attach the original copy face up to the bottom of the mould and pour the concrete on top of it. Bubbles will rise away from the Object. You may need to use Vaseline around the edges to prevent Cement from going underneath the object
Many thanks Mori for your comment and contribution. Good to know FormOil concrete releaser possibly is better than just grease, which doesn't work very well.
Rod seal your wood mold with clear coat from spray cans and then let it cure. Then use some kind of mold release agent, which can be oil or wax and then pour concrete on it. You can also use plaster of paris instead of concrete. As others have said u might wanna de-gas your pour mixture. Lastly dont forget to dry your mold completely and pre heat it before pouring. Happy casting.
Thanks Super Saiyan, these are very good ideas, in particular sealing the wood before oiling it (the wood absorbes oil too easy and isn't a good release agent for a silicone mold.
@@RODsDIY Try Enamel paint for sealing the wood and then clear coat or spray paint over it. Then the cheapest but the best release agent i have used over clear coat is Vaseline, keep it a secret hahaha.
@@iamtoxic1 Thanks for your contribution. Now we have an extensive list of options: Oils, wax, motor oil, vaseline, spirits, varnish, paint. I think I'll try the spirits, Irish spirits. :)
You could try to put the mixture in a vacuum pot which should remove the air bubbles. Are you worried about the mixture exploding when the molten metal contacts water in the concrete (spalling)?
Hi Mark, thanks for commenting. Yeah, it would be a great advantage to have a vacuum chamber, in fact I've seen some DIY in youtube that wouldn't be too difficult to make if you have the proper materials. No, I'm not worried about the concrete withholding water bubbles. Concrete by principle is porous so if you give it enough time to dry, all water will leave. Removing air bubbles has more to do with the fact they occupy space, and after they dry out they leave a hole. That hole will be part of the mold and if it's on the surface it will produce a bump on the cast, which you'll have to carve out afterwards. I don't have a Dremmel or other micro carving tools, so I have to try and get the produce as perfect as possible with the cast.
Where I have had problems with molten metal exploding is when throwing recycled/waste metals into my crucible. If one is not careful some bits of waste metals can have water or other substances in them, which when contacting molten metal explode. And, yes, I've had my dose of that. Learned the lesson quickly.
@@RODsDIY there are also some small affordable vacuum chambers available online if you just want to do a small sample/test. I got a 1-2 quart sized vacuum chamber off Amazon for about 35$ if i recall right. They had larger sizes but i forgot how much they cost.
Hi @@TheGrandShadow_DERPTASTIC , thanks for your comment. Yes, that's a bit small for this mold. For the time being I'm focused on doing all I can to find a cheap permanent mold and the quality of the produce is secondary. When I get into vacuuming the solutions I think I'll try the DIY option because I'm not very wealthy, alhough I'm sure it's not an easy project in terms of safety. A glass bell under pressure can be an accident waiting to happen.
@@RODsDIY And thank you for the idea of refractory cement and silica sand. Ive been working on building the necessary tools and resources to start a small jewelry business to help me on the side with school. Its been a slow buildup over the past few years, and the only details i haven't fully worked out yet are the foundry and mould material. Im planning on going for a DIY induction foundry, and when i was looking up alternatives to plaster, i found your video. I had some ideas of my own on how to solve it, but they would be more difficult and time consuming to attempt.
As far as the bubbles are concerned, if you had placed the pattern at the bottom of the flask then any air or gas bubbles would rise away from the pattern with the help of tapping and vibration. Apart from that I defer to Martin for his expertise.
I see all the comments saying coat the wood I think they are wrong the wood absorbed some moisture from the concrete but I believe if you had put this in a preheated 350f degree oven for a brief period the wood would tighten up and release from the concrete easily
Thanks for your comment Dean. You are right, wet wood shrinks when drying. Probably I shouldn't have wetted it before blowing the torch over it, or I didn't give it enough torch time. Maybe, as you say, an oven would have released it.
Definitely if you had covered the mold with wax It should have come out rather easy. and the use of a vibrator when pouring the cement , may have lifted all the gas bubbles up and out, or create a vacuum chamber to suck all the gasses out. like they do when making a carbon fiber object or taking the air out of castings done with resins.
How about if you make a silicone rubber mold first, peel it off the master copy, pour wax into the rubber mold, let it set, lift the wax master out of the rubber mold, Use the wax master to produce a cement/plaster mold. Melt wax out of mold. Might be a long way round but you wouldn't have to break your mold to release your master.
Hi Jim Yes, I tried that (ua-cam.com/users/edit?o=U&video_id=UHKFJQHiCok&feature=vm) but used a mixture of refractory cement + silica sand which proved to delicate for the job. The silica sand makes it crumble too easily. I could have tried another attempt just with refractory cement as a final mold (which probably would work fine for a few copies), but I decided to go for a bigger target: trying to make a bronze mold in which I could pour aluminum. If it works out right I should be able to produce many more copies in that. I'm ready to pour the bronze in so I should have a video coming up soon on this topic. Please come around again.
Thank you for allowing me space to stand upon your shoulders.
Hopefully I'll learn something myself worthy of passing on.
Thanks for your comment Colonel. Do have a look at the last video of this series (link in the description), you'll find my final take of all this. I hope it helps.
I’m with the colonel. This video is amazing and your no nonsense, no frills straightforwards diy approach is amazing. Also your skill in executing the task at hand and ability to explain what you’re doing and why you’re doing it is next level. Thanks for this video, and the time you took to make it. It’s perfect in every way. About to order the refractory cement and wait for it in the mail like it’s Christmas. I have a knob that’s missing on a table saw from 1933, and it’s gonna be awesome replicating the twin of the missing knob to make the saw that much closer to being complete, with all original parts, down to the nuts and bolts.
Love from New Zealand pal, appreciate a diy hack so will try with glass casting
Beautiful work that with glass, but utterly delicate.
Very nice video I'm going to try this method this week
Thanks for your comment Zachary. Good luck.
Wonderful work by the elegant gentleman. It really helped me thank you very much. I appreciate.
Thanks for your comment Vishva, I'm happy to have been useful.
Rod, thanks so much! I’ve been searching for a video like this all day!
Many thanks for your comment Edward. It's a pleasure to hear viewers are getting something out of my videos. I'll be posting a video in the following hours about risks and hazards in foundry. Stay tuned.
Thank you for the idea
And thanks to you for commenting.
Very useful Sr. Another subscriber 😎 🍻
Thanks, gracias Rene. :)
What a great idea, thank you, Rod!
Many thanks for your comment Enigma.
Thank You for sharing with us older fellows. Birthday Boy I am!
Well. Happy Birthday then.
Vidéo intéressante ! C’est du ciment réfractaire mélanger à quoi ?
Merci samedi pour votre commentaire. Il est mélangé avec du sable siliceux de type sucre, mais il s'est avéré très cassant.
Thank you good sir. I have subscribed and look forward to seeing more from you.
Thanks for your comment and sub Jesse. In the near future I'm going to offer a special privilege for those who are subscribed.
@@RODsDIY oh I believe I can speek for everyone, its privelage enough just to get years long secrets, tips and tricks 😀
@@jessemartinez6781 The truth is, the privilege is mine, as in many cases I'm only giving back knowledge I received for free when I was young and needed a hand.
thank you .. this method helped solve some issues i was having
Great, happy to hear that. Comes to think, someone's failure can become someone else's success. Great.
been looking for a permanent mold solution .. i am watching your 2nd video about this now @@RODsDIY
Really good job!
Thanks for your comment Ted.
Rod, The process should be viable for simple shapes, Stone moulds were used during the middle ages for small bronze parts and way before that for things like arrowheads and spear tips. It was a fairly soft stone - soapstone or soft sand stone I suspect, something that could be easily carved. I am dubious of its applicability to larger work as the contraction of the castings will lock them into the die and while some form of ejection mechanism is entirely possible each time a casting s removed some of the relatively brittle die will rub off - the die will thus be a fairly short life affair. The aluminium dies that I occasionally use proved to be total disasters if the part being cast could shrink onto the die in anyway, The use of wood for the master has problems as even if well varnished and greased it will possibly /probably swell when it gets wet and lock into the cast block. Making it, as you found, impossible to remove without damage to one or both. Quite vicious vibration during placement of the refractory may help get rid of those bubbles - an out of balance motor under a spring mounted table, but you need to have strong mould boxes. Good luck... Martin
Wow! You can't make someone happier reading such a detailed and knowledgeable analysis of my attempts and the options. In your words you show you care for other people and for this art, and that is very valuable. Many thanks. I have been considering the possibility of creating a bronze die, to pour my aluminium into, but I hadn't thought that the cast contracts when cooling. A locked cast would be just too bad, and considering the complexity of my model that's what probably would happen. And if we add to that, that some parts of the figure might not have a perfect angle for extraction, a locked cast is the most probable situation with a metal die if I can't fine tune every angle of the figure. Maybe an impossible task. BTW, I would like to send you a virtual present in recognition of your friendship: a nice pair of good gloves. Take care of those hands.
Please tell me you made the video... i need to see that following video!
Hello Kyril. This video is part of a series of failures in trying to make a permanent mold for a complex figure. In the final video I am able to produce a successful mold, but only workable with a simple figure: ua-cam.com/video/7U38teByJkQ/v-deo.html
I'm looking for a material for one time cast for silver, lost wax, that doesn't need to be pressurized and either doesn't need to be baked or can be done in an oven,
Hi Hex. If you refer to the mold, a mixture of plaster and silica sand can be heated in an oven for drying and getting the wax out, and although nobody forces you to use pressure (a vaccum) the surface will end up with bubbles. If you refer to silver, there is no way you can cast silver in a kitchen oven, as the temperature rarely gets above 200ºC.
If you cover the wood with gas or light motor oil. It helps the concrete from sticking. Remove when concrete is slightly hard. And for air pockets we just tap forms with a hammer. Local 528 adamant mason hope that helped some?
Thanks Haloforever, I'll try that. Lucky I don't have a Tesla.
Attach the original copy face up to the bottom of the mould and pour the concrete on top of it. Bubbles will rise away from the Object. You may need to use Vaseline around the edges to prevent Cement from going underneath the object
Nice video
Thanks for your comment Bradley.
Form oil on the wood from the concrete industry would help the wood release from the refractory cement.
Many thanks Mori for your comment and contribution. Good to know FormOil concrete releaser possibly is better than just grease, which doesn't work very well.
Rod seal your wood mold with clear coat from spray cans and then let it cure. Then use some kind of mold release agent, which can be oil or wax and then pour concrete on it. You can also use plaster of paris instead of concrete. As others have said u might wanna de-gas your pour mixture. Lastly dont forget to dry your mold completely and pre heat it before pouring. Happy casting.
Thanks Super Saiyan, these are very good ideas, in particular sealing the wood before oiling it (the wood absorbes oil too easy and isn't a good release agent for a silicone mold.
@@RODsDIY Try Enamel paint for sealing the wood and then clear coat or spray paint over it. Then the cheapest but the best release agent i have used over clear coat is Vaseline, keep it a secret hahaha.
@@RetrowaveUniverse Thanks, I'll try that. Don't worry, my lips are sealed.
@@RODsDIY I've found that a bit of mineral spirits with vasilone thins it out and makes it easier to spread and cover more evenly.
@@iamtoxic1 Thanks for your contribution. Now we have an extensive list of options: Oils, wax, motor oil, vaseline, spirits, varnish, paint. I think I'll try the spirits, Irish spirits. :)
This is useful
Thanks for your comment, DeadToro.
You could try to put the mixture in a vacuum pot which should remove the air bubbles. Are you worried about the mixture exploding when the molten metal contacts water in the concrete (spalling)?
Hi Mark, thanks for commenting. Yeah, it would be a great advantage to have a vacuum chamber, in fact I've seen some DIY in youtube that wouldn't be too difficult to make if you have the proper materials. No, I'm not worried about the concrete withholding water bubbles. Concrete by principle is porous so if you give it enough time to dry, all water will leave. Removing air bubbles has more to do with the fact they occupy space, and after they dry out they leave a hole. That hole will be part of the mold and if it's on the surface it will produce a bump on the cast, which you'll have to carve out afterwards. I don't have a Dremmel or other micro carving tools, so I have to try and get the produce as perfect as possible with the cast.
Where I have had problems with molten metal exploding is when throwing recycled/waste metals into my crucible. If one is not careful some bits of waste metals can have water or other substances in them, which when contacting molten metal explode. And, yes, I've had my dose of that. Learned the lesson quickly.
@@RODsDIY there are also some small affordable vacuum chambers available online if you just want to do a small sample/test. I got a 1-2 quart sized vacuum chamber off Amazon for about 35$ if i recall right.
They had larger sizes but i forgot how much they cost.
Hi @@TheGrandShadow_DERPTASTIC , thanks for your comment. Yes, that's a bit small for this mold. For the time being I'm focused on doing all I can to find a cheap permanent mold and the quality of the produce is secondary. When I get into vacuuming the solutions I think I'll try the DIY option because I'm not very wealthy, alhough I'm sure it's not an easy project in terms of safety. A glass bell under pressure can be an accident waiting to happen.
@@RODsDIY
And thank you for the idea of refractory cement and silica sand.
Ive been working on building the necessary tools and resources to start a small jewelry business to help me on the side with school.
Its been a slow buildup over the past few years, and the only details i haven't fully worked out yet are the foundry and mould material.
Im planning on going for a DIY induction foundry, and when i was looking up alternatives to plaster, i found your video.
I had some ideas of my own on how to solve it, but they would be more difficult and time consuming to attempt.
As far as the bubbles are concerned, if you had placed the pattern at the bottom of the flask then any air or gas bubbles would rise away from the pattern with the help of tapping and vibration. Apart from that I defer to Martin for his expertise.
Yes Mark you are right. Having the figure downwards probably helps to trap bubbles on the figure, and I still could have turned it around afterwards.
Genial!
Thanks for your comment HPR.
i agree with the "permanent" part to this, people throwing away moulds is not very constructive, if theres a way to keep them its worth doing!
I see all the comments saying coat the wood I think they are wrong the wood absorbed some moisture from the concrete but I believe if you had put this in a preheated 350f degree oven for a brief period the wood would tighten up and release from the concrete easily
Thanks for your comment Dean. You are right, wet wood shrinks when drying. Probably I shouldn't have wetted it before blowing the torch over it, or I didn't give it enough torch time. Maybe, as you say, an oven would have released it.
Definitely if you had covered the mold with wax
It should have come out rather easy.
and the use of a vibrator when pouring the cement , may have lifted all the gas bubbles up and out, or create a vacuum chamber to suck all the gasses out.
like they do when making a carbon fiber object or taking the air out of castings done with resins.
Thanks for your suggestions, I'm sure they'll be useful for someone.
How about if you make a silicone rubber mold first, peel it off the master copy, pour wax into the rubber mold, let it set, lift the wax master out of the rubber mold, Use the wax master to produce a cement/plaster mold. Melt wax out of mold. Might be a long way round but you wouldn't have to break your mold to release your master.
Hi Jim Yes, I tried that (ua-cam.com/users/edit?o=U&video_id=UHKFJQHiCok&feature=vm) but used a mixture of refractory cement + silica sand which proved to delicate for the job. The silica sand makes it crumble too easily. I could have tried another attempt just with refractory cement as a final mold (which probably would work fine for a few copies), but I decided to go for a bigger target: trying to make a bronze mold in which I could pour aluminum. If it works out right I should be able to produce many more copies in that. I'm ready to pour the bronze in so I should have a video coming up soon on this topic. Please come around again.
You should soak the wooden model in water for 24h. then it can be released when dried.
Thanks for your comment Timmy. Eventually that should work, but it seems the best would be to cover the wood with oils or grease avoiding it to stick.
Burn the wood
As a last resource, sure, but considering it took me days to carve the model, it's not something I'd be eager in doing. Thanks for your comment.
bla bla bla bla
Tfyc, ie. Brevity is the soul of wit (Shakespeare).
@@RODsDIY bingo.
@@johnlockesghost5592 Thanks, I'll try to create more bingo-focused videos.