This has been absolutely invaluable. I've watched a ton of sandcasting vids but no one has done anything like this for really delicate parts like I'm planning on doing this summer. Jet engine vanes in particular. The unbound sand was something of considerable interest, though as my parts will be ceramic in nature, I'm trying to figure out how to multi-part mold them for wax or foam casting so I don't burn up a 20 hour resin print every time I want to do a run.
tres instructf et tres beau travail .... merci pour les videos.... je suis a la recherche du produit " céramique liquide "... puis je trouver ça en france ??
Hello and thanks for the beautiful video. What kind of glue ? and wich liquid do you use to cover foam ? and wich kind of foam . I would be very thanksfull . and regards
Nothing special. Just dry silica sand. I prefer the extra fine milled and sifted stuff used in mortar and available next to the concrete in the big box store. I use QuikCrete Fine or Extra Fine. It's nice and costs the samd as play sand, which sucks. Best, Kelly
There are so many. Any finishing compound you can by premixed in a pail is going to be non-setting. About the only setting compounds are for use with the tape. I use USG brand but only because I had a pail of it. The light weight and top coat varieties have some addatives that make them perform better as coating for the same reasons they perform well as joint finsihing compound. Just dilute with water to the desired consistency and keep in a sealed container for future use. Best, Kelly
I need a heat sink cast. Not all that ambitous in terms of thin fins. The goal is to get a preform where we don't have to do any machining of the fins to lower costs. The part is kind of big though but not particularly heavy - finished is like 3 kg. Do you know a shop that could figure this out for us? Thanks
I use a single G25 on the 5gallon bucket size molding rig and I use three G25s and two G8s on my 30 gallon size rig. The G8s are too small. Even with a a true 5 hp compressor (about 16scfm @150psig) on an 80 gallon tank I can't sustain those for long but if I charge the tank to 150psi I can pull them for a few minutes and then recharge if necessary. Best, Kelly
@@kellycoffield533 No luck so far......I was hoping that lost foam wasn't all that rare a thing but apparently it is to some degree if one doesn't want to deal with someone in China....
It definitely increases the rate/speed of metal penetration into the foam pattern but I don't think it materially affects cooling because there is very little air flow in the mold due to the film membrane barrier. Best, Kelly
@@kellycoffield533 oh yes the refractory coating I forgot about that. So I am new to all of this and have no experience but I guess I am having trouble understanding how the vacuum would help because of the coating then. That might make for a interesting video of testing light coating vs heavy and vacuum and no vacuum on a easy part to see what's really going on. Thanks for your videos you have converted me from the idea on green sand molding to lost foam for sure.
The coating isn't a barrier. It's porous and permeable. The vacuum can increase the rate at which evaporated foam gases are expelled. I almost never use vacuum on aluminum LF casting except in extreme cases like this example which was just to demonstrate the art of the possible. It can be helpful and necessary on higher melt point alloys like iron, where the foam is evaporated more rapidly and thus require more rapid removal of gas. Best, Kelly
In the bottom of the flask there is a false floor/plenum. The side that faces the flask is a perforated plate covered with 200 mesh stainless steel screen with a rubber seal around the perimeter. You can also use very fine fiberglass cloth instead of the 200 mesh stainless. There is a detailed description of the build here. forums.thehomefoundry.org/index.php?threads/my-new-lost-foam-casting-rig.516/ Best, Kelly
Mario, it's a locally sourced commercial product specifically formulated for lost foam casting, so I'm afraid not practical for you. If you have a foundry supplier, permeable mold washes are very similar. Absent that, non-setting drywall/gypsum board joint compound thinned with water will work fine for non-ferrous casting. It is inexpensive and available at home improvements stores. Best, Kelly
@@kellycoffield533 thank you very much! I read your post in the foundry forum and your comment about the topping cover of drywall. I think I'll try this option. No locals foundry suppliers around. I'm very impressed of your setup and perseverance. Best wishes!
Josh, yes but I don't recall which one, but I believe it may have been in this series. It is product called Poly Cap 600 made by REFCOTEC. Unfortunately there is a 50gal minimum buy that makes it impractical for most hobbyists. Thinned non-setting drywall joint compound is a practical alternative. Adding a (very) small amount of Dawn dishwashing soap serves as a surfactant and helps promote more complete and even coating. I'll elaborate more in my next video. Best, Kelly
Just turn the volume up. It is low but I have absolutely now problem hearing it on my phone, tablet, or with ear buds. If this doesnt do it your speaker is worse than my mic, LoL!
Hah! Oh yes, I'm quite aware. I have friends that are life long foundrymen that like to poke fun at my lost foam casting so I did this to show the art of the possible as far as thickness and to stick it in their ear, because it takes no molding skill whatsoever! They have their Saucer Cup & Spoon and now I have mine :-0 Best, Kelly
@@kellycoffield533 each form of patternmaking has its advantages. For one off part lost, as you do it, may end up being the fastest. If you get an acceptable part first time every time. I built some aluminum molds for expanded styrene patterns for high production. I believe some auto manufacturers are using that for engine blocks. So now in lost foam production it's not feasible for short run casting. I have the patterns for a small steam engine, about 15", high. It less than 14 hrs to build the most complex part, no cad involved. I screwed it up machining. I go grab the pattern off the shelf and can have another that day. It would take my little cnc about 8 hours or more to cut another. That's why patternmakers tease you. That's why I learned cad-cam I can when I can get up again try your way. Keep up the good work.
@@roscoepatternworks3471 The design freedom of evaporative pattern casting is great. I used to think in terms of parting lines, core prints, core boxes, draft/back draft but no longer do so. I just reduce the pattern to easily made pieces, assemble them and vibrate sand around them to mold. The I dump it all on the ground, pluck out my casting, and grin. I also need to condition the sand other can keeping it dry. Mold material cost is almost nil.....Best, Kelly
This has been absolutely invaluable. I've watched a ton of sandcasting vids but no one has done anything like this for really delicate parts like I'm planning on doing this summer. Jet engine vanes in particular. The unbound sand was something of considerable interest, though as my parts will be ceramic in nature, I'm trying to figure out how to multi-part mold them for wax or foam casting so I don't burn up a 20 hour resin print every time I want to do a run.
Glad you found it useful. Good luck on your project. I'll look forward to your video! Best, K
I need to cast some Intake runners for a Hemi intake project...
tres instructf et tres beau travail .... merci pour les videos.... je suis a la recherche du produit " céramique liquide "... puis je trouver ça en france ??
Thanks for the info..very impressive setup.
Hello and thanks for the beautiful video. What kind of glue ? and wich liquid do you use to cover foam ? and wich kind of foam . I would be very thanksfull . and regards
There are videos on my channel on materials, pattern making, and coatings that discuss each one of those subjects. Have a look at those. Best, Kelly
I want to know the materials for making the lost foam
Then I suggest you view the other videos available on my channel on that subject.
13:50 What kind of sand is that?
Nothing special. Just dry silica sand. I prefer the extra fine milled and sifted stuff used in mortar and available next to the concrete in the big box store. I use QuikCrete Fine or Extra Fine. It's nice and costs the samd as play sand, which sucks. Best, Kelly
Hi Kelly, Can you please provide a link to the Non-setting drywall mud that you referred to? I've tried googling this and nothing comes up.
There are so many. Any finishing compound you can by premixed in a pail is going to be non-setting. About the only setting compounds are for use with the tape. I use USG brand but only because I had a pail of it. The light weight and top coat varieties have some addatives that make them perform better as coating for the same reasons they perform well as joint finsihing compound. Just dilute with water to the desired consistency and keep in a sealed container for future use. Best, Kelly
I need a heat sink cast. Not all that ambitous in terms of thin fins. The goal is to get a preform where we don't have to do any machining of the fins to lower costs. The part is kind of big though but not particularly heavy - finished is like 3 kg. Do you know a shop that could figure this out for us? Thanks
I use a single G25 on the 5gallon bucket size molding rig and I use three G25s and two G8s on my 30 gallon size rig. The G8s are too small. Even with a a true 5 hp compressor (about 16scfm @150psig) on an 80 gallon tank I can't sustain those for long but if I charge the tank to 150psi I can pull them for a few minutes and then recharge if necessary. Best, Kelly
Sorry wrong reply, but I too stacked up with my own projects at the moment. Good luck with the search. Best, Kelly
@@kellycoffield533 No luck so far......I was hoping that lost foam wasn't all that rare a thing but apparently it is to some degree if one doesn't want to deal with someone in China....
Is it possible that the vacuuming will add to the metals rate of cooling making it cool faster?
It definitely increases the rate/speed of metal penetration into the foam pattern but I don't think it materially affects cooling because there is very little air flow in the mold due to the film membrane barrier. Best, Kelly
@@kellycoffield533 oh yes the refractory coating I forgot about that. So I am new to all of this and have no experience but I guess I am having trouble understanding how the vacuum would help because of the coating then. That might make for a interesting video of testing light coating vs heavy and vacuum and no vacuum on a easy part to see what's really going on. Thanks for your videos you have converted me from the idea on green sand molding to lost foam for sure.
The coating isn't a barrier. It's porous and permeable. The vacuum can increase the rate at which evaporated foam gases are expelled. I almost never use vacuum on aluminum LF casting except in extreme cases like this example which was just to demonstrate the art of the possible. It can be helpful and necessary on higher melt point alloys like iron, where the foam is evaporated more rapidly and thus require more rapid removal of gas. Best, Kelly
What is the name of the refractory lining you use?
Search my videos for "Refractory Coatings for Lost Foam Casting Patterns". Best, Kelly
how do you keep sand out of the vacuum? I keep staring at the set up and don't understand
In the bottom of the flask there is a false floor/plenum. The side that faces the flask is a perforated plate covered with 200 mesh stainless steel screen with a rubber seal around the perimeter. You can also use very fine fiberglass cloth instead of the 200 mesh stainless. There is a detailed description of the build here.
forums.thehomefoundry.org/index.php?threads/my-new-lost-foam-casting-rig.516/
Best,
Kelly
Hi! Would you please explain what that coat is, and where to get it, if not any replacement , I'm from Argentina.
Mario, it's a locally sourced commercial product specifically formulated for lost foam casting, so I'm afraid not practical for you. If you have a foundry supplier, permeable mold washes are very similar. Absent that, non-setting drywall/gypsum board joint compound thinned with water will work fine for non-ferrous casting. It is inexpensive and available at home improvements stores. Best, Kelly
@@kellycoffield533 thank you very much! I read your post in the foundry forum and your comment about the topping cover of drywall. I think I'll try this option. No locals foundry suppliers around. I'm very impressed of your setup and perseverance. Best wishes!
Have you linked the slurry you use in any of your video descriptions?
Josh, yes but I don't recall which one, but I believe it may have been in this series. It is product called Poly Cap 600 made by REFCOTEC. Unfortunately there is a 50gal minimum buy that makes it impractical for most hobbyists. Thinned non-setting drywall joint compound is a practical alternative. Adding a (very) small amount of Dawn dishwashing soap serves as a surfactant and helps promote more complete and even coating. I'll elaborate more in my next video. Best, Kelly
@@kellycoffield533 thank you sir, I will look forward to seeing it.
Wish I could hear it.....
Just turn the volume up. It is low but I have absolutely now problem hearing it on my phone, tablet, or with ear buds. If this doesnt do it your speaker is worse than my mic, LoL!
You cheated, I've watched molders do green sand molding using a real cup, spoon and saucer. In our foundry it was a test for the apprentices.
Hah! Oh yes, I'm quite aware. I have friends that are life long foundrymen that like to poke fun at my lost foam casting so I did this to show the art of the possible as far as thickness and to stick it in their ear, because it takes no molding skill whatsoever! They have their Saucer Cup & Spoon and now I have mine :-0 Best, Kelly
@@kellycoffield533 each form of patternmaking has its advantages. For one off part lost, as you do it, may end up being the fastest. If you get an acceptable part first time every time. I built some aluminum molds for expanded styrene patterns for high production. I believe some auto manufacturers are using that for engine blocks. So now in lost foam production it's not feasible for short run casting. I have the patterns for a small steam engine, about 15", high. It less than 14 hrs to build the most complex part, no cad involved. I screwed it up machining. I go grab the pattern off the shelf and can have another that day. It would take my little cnc about 8 hours or more to cut another. That's why patternmakers tease you. That's why I learned cad-cam I can when I can get up again try your way. Keep up the good work.
@@roscoepatternworks3471 The design freedom of evaporative pattern casting is great. I used to think in terms of parting lines, core prints, core boxes, draft/back draft but no longer do so. I just reduce the pattern to easily made pieces, assemble them and vibrate sand around them to mold. The I dump it all on the ground, pluck out my casting, and grin. I also need to condition the sand other can keeping it dry. Mold material cost is almost nil.....Best, Kelly
I wonder how many inches of mercury my 6 hp shop vac pulls??? Probably not enough.