Absolutely love your videos. Straight forward no crappy music, great camera angles and simple script describing the process. A big thank you from Australia
I work in a steel foundry where we make green sand and no bake sand molds much bigger. To prevent minute defects in your casting sift a layer of sand over your pattern to get a more fine sand , it will result in a higher quality casting
Hi Davys' you are right I have watched myford boy for 3 years now and I am up to scratch with my casting. I do boat cleats mostly. My father was a brass moulder making propellers near bulldale street yoker. I am up to scratch with my Blacksmithing too thanks to Black Bear Forge.. One can never learn enough, And I am 76 and still working.... ta ta to all.
Forming the ingate is an art; many of my attempts result in poorly filled areas, particularly where the part is thin, or contains fine details. These videos are excellent guides for sorting this all out. Thanks!
5 things will help. add zircon flour to your sand mix, it will take the roughness out of the definition, the other this is dust you molds first this will help with release and definition cut a slag trap in your feeder gate. add a riser this will help to pressure the casting from two sides, it will also feed it when cooling if you want super fine then use a zircon spray coating for your mold, you should be able to achieve close to mirror finish Great work!
Love your videos. A good source for bentonite is natural bentonite cat litter, it's nearly 100% bentonite. I'm using an old espresso grinder to grind it into a fine powder before mixing it together with sand.
It's been over 30 years since I taught foundry practice in high school and you did a great job, especially with the sand mix. Clarify your clay type though. Over all...you comunicated well. Thank you for the reintroduction to a past love.
Very instructive for those of us on a budget . There is a great wide mouth funnel that is used in canning. I'm sure Wamart sells them as many other stores do. Be a great addition to your shop and save a lot of cleanup ..... and replacing your scale.
If you go to a masonry supply place they will have bags of 120u sand for about 14 bucks/100lbs. Makes for very nice casting sand. Not too fine, not too course. It wont leave grain texture in your casting. Pottery houses sell the powdered bentonite for 2 bucks a pound. {8-10lbs per 100lbs and bag}. Way easier than sifting play sand! and it comes dry :) play sand is usually wet which is why the bags are so small {water is heavy, its packed by weight}
you make this look easy, I've been trying to get a good mold for weeks it either doesn't part off the piece clean, or mold doesn't part clean. Poured one yesterday, mold looked good, still didn't part like yours but thought it would work. Then when I poured it blew out the side. So here I go again. I do however find your work inspiring so will keep watching till I get it right... Thank you for your video's, they've been very helpful....
+Bill Richardson It could be your moisture content is wrong or the bentinite % if you have made your own sand. It takes a bit of practice to get it right
Thank you, I read where 10% clay to sand mix was what you want but that didn't work at all, so I went to adding more clay. Seems to be a lot better I am at about 18% now, most likely pushing the limits. Your videos are so helpful, trying to watch all of them, guess that makes me a fan.... Thanks very much for the reply....
I later used losalt as I feel it gave a better result but I now have some aluminium drossing flux. I haven't noticed the castings are particularly brittle but maybe softer than the doner metal.
I usualy use a commercial sand. I made up this batch just to see how it worked out. Most people would mix dry and add the water later but I found it easier to do it this way. Its not sufficient to just mix it in a concrete mixer it needs to bepushed together. Adding a steel ball to mixer might work.
The extended feeder gives the metal "head". As the metal cools it shrinks and the risers feed the casting. The extension is more important with aluminium than other metals.
@Shannariano The sand I have and made is water bonded so its either a natural clay bearing sand or sand with clay added. Greensand is water bonded. Oil bonded is an alternative.
After looking into it, it's "Sodium Bentonite Ash Clay" that you want, and the sand that I see seems to work best with the mulling (and resolution of cast) is the tamping sand you find at Home Depot or Ace that will work best. I noticed when I got my Play Sand, that it looked too sharp in comparison to myfordboy's sand pick. having more powdered look was the easier choice. I intend to Ball-Mill all of my stuff, including my sand first to get it a little finer. Thank you for inspiring me Ford!
My fordby i was watching a program where in the olden days they would mix only molasses and sand interesting..Passed down through generation in some 3rd world country..Always look forward to you months.
@Shannariano Greensand is water bonded. Its a natural clay bearing sand or sand with added clay. If oil is used instead of water it is Oil bonded like Petrobond which is technicaly not greensand.
@TheT2eL The sand I usual use is not Petrobond just a commercial greensand. home I broke down the sand after use ,charred bits and all looks fine. I think just the colour will darken after a few casts.
myfordboy's greensand ratio, Metric to Imperial: 1kg = 2.21# (sand) to 120g = 0.27# (bentonite) I recommend watching the entire video though....now you just don't have to convert it
Any fine sand should be fine. The finer the sand the better detail it will mould. Not sure about marble dust. If looked at under magnification It should have irregular grains rather than round smooth ones so the clay can bond to it.
Dear mr good job..but i have a small suggestion.intead of using small knife for creating ingate(way) you can use some other shapes to do the same some thing like 5mm pipe before creating mold..
The finer the sand the better the finish. Try and get as fine a sand as possible. The water content cannot really be specified as it depends on the moisture content of the sand to start with. You need to add water until it holds together as shown
@dramey03 This is the first time I have used home made stuff but the results were pretty. good. Maybe a slightly coarser finish than the commersial sand. Down side is its hard work mixing by hand.
You get best results from using aluminium that has been cast before, eg car parts. You can melt aluminium in a stainless container if you have a big enough blowtorch but it wastes a lot of gas.
Do you mean "what are the castings for ?" They are for model engines. They can be seen at my Model engine videos playlist, on my channel page. I still have all the engines show in my collection.
The patterns are not made as one and cut in half for the reason you mention. Basically the main pieces are stuck together with newspaper between, then after machining or shaping they are split apart. I have videos on pattern making making showing the process.
Baking SODA is pure sodium bicarbonate, a mild alkalai. Washing soda is sodium carbonate, a stronger alkalai. Baking POWDER is baking soda with tartaric acid. When wet, baking powder releases gas and neutralizes itself. That's probably a bad thing.
Hi. I found elsewhere a very similar recipe. There they recommended blasting sand (finer than playground sand) and also said that cat litter (the stuff you fill cats' boxes with) is typically 100% betonite. So if someone cannot find betonite, cat litter might be worth giving a shot. Haven't tried that, though, so that is just a second-hand knowledge. Thanks for your videos, David.
I'm surprised the bentonite worked so well for you, since it's primary factor is its extreme swelling with water. Most I have seen recommend some form of fire clay instead. In ceramics, bentonite clay is on the "never touch the stuff" list, as it's wet-swelling properties make it shrink & crack horribly upon drying.
Here's a link to a page I read that recommends using fire clay: www.backyardmetalcasting.com/buy_fireclay.html However; I just did some more searching & a few sites specifically recommend against using fire clay, and recommend bentonite instead, so I think I'll give your mixture a go ;)
This is amazing the level of detail. I wonder just how precise one can get, though, into the hundredth's, the thousandth's, maybe? (if it's the latter, dang I can think of so many uses for that)
A lot of people machine their castings afterwards. I'm studying to be an engineer, I check these things out. One local machinist told me that his cnc equipment is accurate to the millionth. (English system of measurement)... I'm a 20 year old nobody and I have access to some pretty cool machine shops. So your answer here depends on how much thought and effort you put into the process.
Brandon Morlock I knew CNC stuff could get precise, but DAMN. That's like being able to CNC the optics for a telescope. I should clarify, I'd meant 'precision right out of the casting process' but I'd imagine you'd have to CNC the thing at least a little to bring it into tolerance, no matter how good your casting was.
Brandon Morlock The mathematical calculations might work out to millionths - but machines such as lathes and milling machines will get nowhere close. As an example, the cutter in a lathe flexes slightly. 1/1000th is generally very precise. You also cannot make a good mirror for a Newtonian using CNC - I have made my own and learnt enough to know why (figuring/testing is more of an art than a science)
I myself have never used a machine that claimed such a tolerance. It was a machinist who makes manufacturing equipment who told me this. He may have been full of it, I don't know. I was just enthused that he took me seriously enough to show me around his shop.
Brandon Morlock Todays EDM machines can actually provide accuracy in the range of under a micrometer (which is 1ppm in a meter) and are usually used for finishing precise plastic injection moulds as well as some other obscure manufacturing equipment. Most CNC mills have an accuracy of about +/- 0.01mm while the electronics does its calculations down to 1ppm in mm. There is a big difference between a tools resolution and its accuracy.
I'm no chemist but the baking powder is a different substance to washing soda, maybe this is making your metal rough. The degas should be plunged to the bottom of the metal and bubbles should rise through the metal.
Excellent video in that your comments helped me understand what, & why, you were doing at every stage. I'm just intigued that you didn't create ventholes for the air to escape. The finished result proved they weren't needed in this case, but why?
I learned how to sand cast from a gentleman who preferred to use the commercial oil based sand and he told me that a batch of sand (about 3-4 cups worth, he only did small item) was good for about 200 castings, his preferred metal was pewter, before it started breaking down to a point where you would notice unless you were using something like brass which actually burns the sand while you pour it. How long will it take for this mixture starts to break down and become useless?
The darker sand you have seen me use is a commercial one not home made. The orange coloured sand in my later videos is a natural clay bound sand. The colour of the home made stuff just depends on the colour of the sand used.
When you are mixing compounds together mix in equal parts. if the smallest amount is an ounce get an equal amout an ounce of the larger amount. mix the two equal amounts together. now you have two ounces. mix two ounces of the larger amount with the two ounces you have. mix well. now you have 4 ounces. this method will even well dispersed mixtures. you can use color dies to see the mix taking place.
koby Edwards If you try to cast a metal that hot, the sand in contact with the metal will probably also melt - platinum melts at 1768°C and in fact most rocks and concrete do melt or soften at temperatures >1250°C (check out my video of melting concrete). It will probably work anyway since the metal will cool down and solidify before the sand melts enough to deform the casting significantly - the problem is if molten sand get stuck in the metal and destroy the surface. If you use sand intended for casting it probably works better - play sand has lower melting point then "real" casting sand Although - that's probably the least of your concerns since the amount needed to make even a small casting will cost as much as a new car. It is even more expensive than gold.
All these making casting sands are overboard. For aluminum mix topsoil with lard and talc it with baby powder. Much smoother. And cost is everything.Almost all topsoils contain the proper mixture automatically in nature. Large companies who make critical automotive engine blocks designed these sands, but the backyard average joe only pours aluminum parts aren't critical.
This is really impressive. No matter how often I see casting done, I am always happy to watch more.
Absolutely love your videos. Straight forward no crappy music, great camera angles and simple script describing the process. A big thank you from Australia
Perfect demonstration.
Last time I did this was 46 years ago. Memories flooding back. Thank you.
guy comes from the country with the coolest accent when speaking english and he makes a whole long video without saying a word.
I work in a steel foundry where we make green sand and no bake sand molds much bigger. To prevent minute defects in your casting sift a layer of sand over your pattern to get a more fine sand , it will result in a higher quality casting
That is what I was going to say
I've seen him do it in other videos
You will not get a smooth as cast finish with that sand you need a facing sand
Hello there. Can I cast stainless steel parts with this mixture of play sand??
2:10 seems casting sand is without water just oil that stands high temperatures
Hi Davys' you are right I have watched myford boy for 3 years now and I am up to scratch with my casting. I do boat cleats mostly. My father was a brass moulder making propellers near bulldale street yoker.
I am up to scratch with my Blacksmithing too thanks to Black Bear Forge..
One can never learn enough, And I am 76 and still working.... ta ta to all.
Forming the ingate is an art; many of my attempts result in poorly filled areas, particularly where the part is thin, or contains fine details. These videos are excellent guides for sorting this all out. Thanks!
5 things will help.
add zircon flour to your sand mix, it will take the roughness out of the definition, the other this is dust you molds first this will help with release and definition
cut a slag trap in your feeder gate.
add a riser this will help to pressure the casting from two sides, it will also feed it when cooling
if you want super fine then use a zircon spray coating for your mold, you should be able to achieve close to mirror finish
Great work!
Hello there. Can I cast stainless steel parts with this mixture of play sand??
@@umbeatable2770 yes
Hello there lathe machinist over here can i melt and cast carbon steelcand stainless steel in a propane melter ( melt and pour into a mold ) ty
@@marcwire9332 wow lol u responded after 6 years
Xin bạn cho tôi hỏi cát pha với loại gì nữa để tạo ra hỗn hợp để có thể đúc được xin cảm ơn rất mong được nhận được câu trả lời từ bạn
I have seen a lot of professional videos, but your video, sir, showed me more than all of them together. Well done!
Love your videos. A good source for bentonite is natural bentonite cat litter, it's nearly 100% bentonite. I'm using an old espresso grinder to grind it into a fine powder before mixing it together with sand.
A riser is not needed for small castings like this. You can add vents if you wish but the porosity of the sand will expel the air.
Please go to myfordboy.blogspot.com and look at the TIPS and FAQ page.
There is a list of recommended books
Absolutely loved watching the whole casting series
It's been over 30 years since I taught foundry practice in high school and you did a great job, especially with the sand mix. Clarify your clay type though. Over all...you comunicated well. Thank you for the reintroduction to a past love.
Hello sir
I have details at myfordboy.blogspot.com
@bladder1010 The air escapes through the porous sand. if it were a larger casting I would have added a riser at the oposite side to the feeder.
Thank you for taking the time and documenting your Blacksmithing, it's very much appreciated
Very good video. I highly recommend this one for anyone wishing to learn the sand casting process.
Very instructive for those of us on a budget . There is a great wide mouth funnel that is used in canning. I'm sure Wamart sells them as many other stores do. Be a great addition to your shop and save a lot of cleanup ..... and replacing your scale.
@joycicles I used 12 % bentonite. More details at myfordboy.blogspot.com
If you go to a masonry supply place they will have bags of 120u sand for about 14 bucks/100lbs. Makes for very nice casting sand. Not too fine, not too course. It wont leave grain texture in your casting. Pottery houses sell the powdered bentonite for 2 bucks a pound. {8-10lbs per 100lbs and bag}. Way easier than sifting play sand! and it comes dry :) play sand is usually wet which is why the bags are so small {water is heavy, its packed by weight}
you make this look easy, I've been trying to get a good mold for weeks it either doesn't part off the piece clean, or mold doesn't part clean. Poured one yesterday, mold looked good, still didn't part like yours but thought it would work. Then when I poured it blew out the side. So here I go again. I do however find your work inspiring so will keep watching till I get it right... Thank you for your video's, they've been very helpful....
+Bill Richardson It could be your moisture content is wrong or the bentinite % if you have made your own sand. It takes a bit of practice to get it right
Thank you, I read where 10% clay to sand mix was what you want but that didn't work at all, so I went to adding more clay. Seems to be a lot better I am at about 18% now, most likely pushing the limits. Your videos are so helpful, trying to watch all of them, guess that makes me a fan.... Thanks very much for the reply....
You can get material to rejuvinuate the sand. I haven't noticed any change in my commesial sand after years of use.
I later used losalt as I feel it gave a better result but I now have some aluminium drossing flux.
I haven't noticed the castings are particularly brittle but maybe softer than the doner metal.
I usualy use a commercial sand. I made up this batch just to see how it worked out. Most people would mix dry and add the water later but I found it easier to do it this way. Its not sufficient to just mix it in a concrete mixer it needs to bepushed together. Adding a steel ball to mixer might work.
Your videos are great, with what I learnt from you I produced my first and successful casting yesterday.
It's to give a bit of pressure and to feed the mould as the metal shrinks as it cools.Also its easier to pour into.
The plastic blocks are known as modesty blocks. If you go to myfordboy.blogspot.com there is a page all about making the flasks.
The extended feeder gives the metal "head". As the metal cools it shrinks and the risers feed the casting. The extension is more important with aluminium than other metals.
How I wish I had a country like urs were every thing is kept for people who wanna be succesful well u did a great job there
@Shannariano The sand I have and made is water bonded so its either a natural clay bearing sand or sand with clay added. Greensand is water bonded. Oil bonded is an alternative.
It feeds the casting with metal as it cools and gives pressure to fill the mould.
After looking into it, it's "Sodium Bentonite Ash Clay" that you want, and the sand that I see seems to work best with the mulling (and resolution of cast) is the tamping sand you find at Home Depot or Ace that will work best. I noticed when I got my Play Sand, that it looked too sharp in comparison to myfordboy's sand pick. having more powdered look was the easier choice. I intend to Ball-Mill all of my stuff, including my sand first to get it a little finer.
Thank you for inspiring me Ford!
My fordby i was watching a program where in the olden days they would mix only molasses and sand interesting..Passed down through generation in some 3rd world country..Always look forward to you months.
Thanks for your videos. They are very beautiful, well made, interesting and very instructive!
I really like that you take the time so I can learn a thing or 2 about lead smelting T-Y
@Shannariano Greensand is water bonded. Its a natural clay bearing sand or sand with added clay. If oil is used instead of water it is Oil bonded like Petrobond which is technicaly not greensand.
@OutDoorsMan1342 Yes it can be used over and over.
@StrongBlair The same sand is good for brass.
I really like video bcoz you explained in detail from A to Z
@TheT2eL The sand I usual use is not Petrobond just a commercial greensand. home I broke down the sand after use ,charred bits and all looks fine. I think just the colour will darken after a few casts.
Thank you very much for the vídeos! I use them in my lessons.
Greatings from Valencia, Spain.
myfordboy's greensand ratio, Metric to Imperial:
1kg = 2.21# (sand) to
120g = 0.27# (bentonite)
I recommend watching the entire video though....now you just don't have to convert it
The sand is coarser than the black stuff. I would advise using a natural greensand if you can get it.
Any fine sand should be fine. The finer the sand the better detail it will mould. Not sure about marble dust. If looked at under magnification It should have irregular grains rather than round smooth ones so the clay can bond to it.
Thank you for your response - good info - sounds like a lot, but we get out what we put in.
Dear mr good job..but i have a small suggestion.intead of using small knife for creating ingate(way) you can use some other shapes to do the same some thing like 5mm pipe before creating mold..
hi from mark thank you for sharing your casting experience --- i appreciate it
Lost wax casting is one option but you can get great detail with Petrobond sand.You would need a proper crucible for the silver.
another brilliant video. fascinating and relaxing to watch. love the ambient sounds. all very zen
Thank you for a clear and well done lesson. I never knew how casting was done.
The finer the sand the better the finish. Try and get as fine a sand as possible.
The water content cannot really be specified as it depends on the moisture content of the sand to start with. You need to add water until it holds together as shown
@ecksjay89 It came from a different place in the country. Some natural sand could be red or brown.
Always wonderful clear and instructive videos , ty
Yes I have some. It give a great finish but its more expensive and you loose a little each time as it bakes where it touches the metal.
@dramey03 This is the first time I have used home made stuff but the results were pretty. good. Maybe a slightly coarser finish than the commersial sand. Down side is its hard work mixing by hand.
Very Educat9ional , and well presented !
@Shandybrother There is a link at myfordboy.blogspot.com for a UK supplier.
You need something smaller and more controllable than a mallet to ram the sand tight against the pattern.
Love the video, love the background sound...it's so relaxing.
I am really enjoying your videos, thank you very much!
You get best results from using aluminium that has been cast before, eg car parts. You can melt aluminium in a stainless container if you have a big enough blowtorch but it wastes a lot of gas.
Do you mean "what are the castings for ?" They are for model engines. They can be seen at my Model engine videos playlist, on my channel page. I still have all the engines show in my collection.
@marcuslb95 Worth a try I suppose. They use clay and dung in India to make bells.
Around the place where I live about 30cm deep is a layer 30 to 40cm of such sand. It can be easily pressed and holds its form.
The patterns are not made as one and cut in half for the reason you mention.
Basically the main pieces are stuck together with newspaper between, then after machining or shaping they are split apart. I have videos on pattern making making showing the process.
@stirlinguvstroj This is most people do it but I didn't find it mixed very well that way.
Baking SODA is pure sodium bicarbonate, a mild alkalai. Washing soda is sodium carbonate, a stronger alkalai. Baking POWDER is baking soda with tartaric acid. When wet, baking powder releases gas and neutralizes itself. That's probably a bad thing.
10-14% bentonite, 4-6% humidity, tons of mixing ... I have done this countless times, including lab tests 😊
Hello there. Can I cast stainless steel parts with this mixture of play sand??
@@umbeatable2770 Yes. Eventually opt for 3-4% humidity
What might work well for mixing/stirring would be a paint mixer on an electric drill - pretty sure 30 seconds would do it. Worth a try?
Hi. I found elsewhere a very similar recipe. There they recommended blasting sand (finer than playground sand) and also said that cat litter (the stuff you fill cats' boxes with) is typically 100% betonite. So if someone cannot find betonite, cat litter might be worth giving a shot. Haven't tried that, though, so that is just a second-hand knowledge. Thanks for your videos, David.
Sir, thank you for your response. I asked my question one video too soon since the newspaper trick was demonstrated in #27. thanks again
@svenp More details at myfordboy.blogspot.com
Very good video for sand casting process.
I think that graduating to a work bench is about time.
You should be able to do that ok if the fins are not too thin.
@OutDoorsMan1342 Yes over and over.
IF YOU HAVE YOUR TALC IN A SOCK YOU CAN USE IT FOR A VERY EVEN POWDER ON YOUR PARTING. JUST KEEP THE TALC SOCK IN A JAR WHEN NOT IN USE.
@Dancerpro1 Its best to feed each one seperatly.
Btw, a rubber hammer is ideal for compressing the sand!
I'm surprised the bentonite worked so well for you, since it's primary factor is its extreme swelling with water. Most I have seen recommend some form of fire clay instead. In ceramics, bentonite clay is on the "never touch the stuff" list, as it's wet-swelling properties make it shrink & crack horribly upon drying.
Robherc H I have never heard of fire clay to make greensand, are you thinking of making refractory?
Here's a link to a page I read that recommends using fire clay: www.backyardmetalcasting.com/buy_fireclay.html However; I just did some more searching & a few sites specifically recommend against using fire clay, and recommend bentonite instead, so I think I'll give your mixture a go ;)
This is amazing the level of detail. I wonder just how precise one can get, though, into the hundredth's, the thousandth's, maybe? (if it's the latter, dang I can think of so many uses for that)
A lot of people machine their castings afterwards. I'm studying to be an engineer, I check these things out. One local machinist told me that his cnc equipment is accurate to the millionth. (English system of measurement)... I'm a 20 year old nobody and I have access to some pretty cool machine shops. So your answer here depends on how much thought and effort you put into the process.
Brandon Morlock I knew CNC stuff could get precise, but DAMN. That's like being able to CNC the optics for a telescope. I should clarify, I'd meant 'precision right out of the casting process' but I'd imagine you'd have to CNC the thing at least a little to bring it into tolerance, no matter how good your casting was.
Brandon Morlock
The mathematical calculations might work out to millionths - but machines such as lathes and milling machines will get nowhere close. As an example, the cutter in a lathe flexes slightly. 1/1000th is generally very precise. You also cannot make a good mirror for a Newtonian using CNC - I have made my own and learnt enough to know why (figuring/testing is more of an art than a science)
I myself have never used a machine that claimed such a tolerance. It was a machinist who makes manufacturing equipment who told me this. He may have been full of it, I don't know. I was just enthused that he took me seriously enough to show me around his shop.
Brandon Morlock
Todays EDM machines can actually provide accuracy in the range of under a micrometer (which is 1ppm in a meter) and are usually used for finishing precise plastic injection moulds as well as some other obscure manufacturing equipment. Most CNC mills have an accuracy of about +/- 0.01mm while the electronics does its calculations down to 1ppm in mm. There is a big difference between a tools resolution and its accuracy.
It gives a head of metal to feed the mould as it cools.
I'm no chemist but the baking powder is a different substance to washing soda, maybe this is making your metal rough. The degas should be plunged to the bottom of the metal and bubbles should rise through the metal.
THANK YOU. Making casting sand is as easy as a cup of TEA.
Yes thats what I use.
No, experience. Add a little at a time until it holds together like shown.
I think you are referring to the patterns, These are made of wood. i have videos on pattern making like part 22 in this series.
Now was not necessary entry and exit of molten aluminum?
What is the difference?
Thank you
Watch of Brazil. (google translator)
On a small casting a vent is not necessary. On a larger one the riser will feed the casting with metal as it cools.
myfordboy what do you class as a small cast? something the size of two fingers up to a fist?
Have a look at video 29 and 33 in this series.
At last a good video ! I would suggest a sand muller because mixing by hand is really a chore!
I don't put a riser on the small pieces.
Excellent video in that your comments helped me understand what, & why, you were doing at every stage.
I'm just intigued that you didn't create ventholes for the air to escape. The finished result proved they weren't needed in this case, but why?
The sand gives a degree of venting. Normal practice recommends venting but I have not found it necessary. It is however important to vent cores.
I learned how to sand cast from a gentleman who preferred to use the commercial oil based sand and he told me that a batch of sand (about 3-4 cups worth, he only did small item) was good for about 200 castings, his preferred metal was pewter, before it started breaking down to a point where you would notice unless you were using something like brass which actually burns the sand while you pour it. How long will it take for this mixture starts to break down and become useless?
The darker sand you have seen me use is a commercial one not home made.
The orange coloured sand in my later videos is a natural clay bound sand.
The colour of the home made stuff just depends on the colour of the sand used.
@myfordboy thanks i think i might have a go at casting soon
When you are mixing compounds together mix in equal parts. if the smallest amount is an ounce get an equal amout an ounce of the larger amount. mix the two equal amounts together. now you have two ounces. mix two ounces of the larger amount with the two ounces you have. mix well. now you have 4 ounces. this method will even well dispersed mixtures. you can use color dies to see the mix taking place.
great people do great things. thanks elliott
Two things one it's cool that you reply to everyone and also could green sand work with platinum or is that to hot of a metal
The sand would work but you may not be able to get the metal hot enough to melt at home.
koby Edwards If you try to cast a metal that hot, the sand in contact with the metal will probably also melt - platinum melts at 1768°C and in fact most rocks and concrete do melt or soften at temperatures >1250°C (check out my video of melting concrete).
It will probably work anyway since the metal will cool down and solidify before the sand melts enough to deform the casting significantly - the problem is if molten sand get stuck in the metal and destroy the surface. If you use sand intended for casting it probably works better - play sand has lower melting point then "real" casting sand
Although - that's probably the least of your concerns since the amount needed to make even a small casting will cost as much as a new car. It is even more expensive than gold.
All these making casting sands are overboard. For aluminum mix topsoil with lard and talc it with baby powder. Much smoother. And cost is everything.Almost all topsoils contain the proper mixture automatically in nature. Large companies who make critical automotive engine blocks designed these sands, but the backyard average joe only pours aluminum parts aren't critical.