If you're interested in any of the tools or equipment I use and you want to help support the channel then don't forget to check out some of the affiliate links in the video description. Thank you for the support!
I did bronze casting in college - incredibly satisfying, but a lot of work. We used the lost-wax process (cire-perdue). This 3D printing method looks fascinating.
"80 thousandths of an inch" sounds so complicated compared to 2 millimeters. It always gets me. Thinking if people can really imagine some tiny thousandths of something. Either way, super cool project. I saw this measuring cup being used by the "as seen on TV" guy. It didn't seem overly practical, at least in the way he used it. But making a bronze version is pretty awesome 👍 and the quality of your casting is superb.
I suppose thou(sandths of an inch) is a weird unit if you don't hang around US machinists, but there's a few intuits for it: a hair is a few thou, a playing card is about 10 or 12, the wire in a paper clip, something like 40 thou. While no one could feel a difference in width between 40 thou and 41, it's likely that you'd feel a burr 1 thou high on an otherwise smooth surface. Imagine a fine hair on a glass plate. 1 inch is not really long, but its long enough that 1 thousandth of an inch is tiny, but in some contexts, still very much perceptible. Just my 2c. Have a good one.
Thanks for tuning in to another installment of, “words I didn’t know before!”: 1. Sprue: A channel or funnel through which metal or plastic is poured into a mold. 2. Vitrify: To convert (something) into glass or a glasslike substance, typically by exposure to heat. 3. Lost PLA Method: The model is placed in a plaster mold and the mold is heated until the wax liquefies and flows out of a hole in the bottom (hence the “lost-wax” part of lost-wax casting). Liquid metal is then poured into the mold, which flows into the imprint of the design left in the baked plaster. Tune in next week to find out precisely where my vocabulary was lacking (or REMEDIAL for the kids following along at home!)!
You have created something that your descendants can still marvel at, with your name on it and a small inscription, they can still remember you many years later.
Was the measurement still accurate? I worked in a bronze foundry years ago and I would have been send home when wearing those shoes! We wore wooden shoes only as they can be kicked off and offer some seconds before burning through when your cast leaks and liquid metal spills out. Cool shape, thanks for sharing, stay safe.
@@edwardssistershands Well one tablespoon is 14.786788602728 ml. I don't know any recipe in the kitchen that would be measured with such a device that is ruined by 0.2132114 ml of something that inaccuracy you have with pretty much any kitchen measure anyways. Especially by volume.
I was thinking about how impractical and bulky this would be in the kitchen. Stacking measuring cups are far more practical but this looks really cool.
@@AquarianNomadic with plates, a scale and a measuring jar(idk how to call it, sorry for bad english) its more than enough for me but i get where you are coming from.
Man, I've never seen someone use a slurry like that. Definitely going to look into it when I get back into casting. I'm already stocking up on old radiators and such
While I don't think it would have worked with this project, I really like what BigstackD does with Petrobond. If you haven't seen his channel, check it out. It's awesome to me that for a channel where no one says a word, the dude is freaking hilarious! If you haven't seen the channel, check it out!😎🤙
@@TheRisskee he doesnt seem to like doing lost castings, Im not sure why. He does the odd styrofoam lost casting I guess. The petrabond seems really finicky and I feel like his castings never turn out quite this perfect. My theory being that the molds are inherently forced to be cold, so the metal doesnt cool evenly. Love that Aussie tho
looks great, i printed and used some of these myself. for the finish, i really liked how smooth you got the bottom with the large disc sander. i would do the same with each of the sides. with their rims all the same smooth, shiny metal, it would contrast quite nicely to the rest. and you could even get a more elegant look if you sand the rims until the edges are pointy
Also be an interesting contrast if the insides were highly polished, [vibratory medium polisher, perhaps ?] and the base and outer corners were left matt finish. That would be perhaps a little easier to clean if used for actual cooking measurements
Don't be so hard on your self, you did a great job on this. I have not seen anyone do it better so I think that is a great way of scaling how well you did. Thanks for the video, always fun to see what your going to work on next.
You ever thought about an acid bath, it'll clean it up and may help get rid of some lay lines and tool marks before you polish the pieces up. I love these craftsmanship channels. Keep up the good work
I'm a 3D printing and metalworking mechanical engineer and I learned stuff in this video, thanks! Great work on your casting! Great to see some professional-level technique used in a UA-cam casting vid. Personally I might have smoothed the 3D print a little first... but that would have been a PITA and you did a great job anyway. To remove the ceramic shells - I've actually re-furnaced my pieces after doing the initial cleanup. The shell can fall off in circumstances like that, due to differential expansion. Might have saved you some sandblasting time.
Whoa, this looks sooo cool 🥰 I got a 3D - printer for architecture model printing and that model itself had been on my list for a while as well . I didn't even know one could use it along with ceramic slurry to make metal castings, that's so cool to see!
Having the ceramic shell helps a lot. Not only in allowing the original PLA template to melt out and leave a perfect negative void, but also with the pouring of the cast as it's perfectly able to withstand the heat/pressure of the molten alloy at the temperature required for it to remain liquid long enough to fill every space. The results speak for themselves.
@@Flederratte yeah.... pretty easily missed but that's life when looking at someone else doing something on a sidenote, trying to learn smithing from an old-fashioned smith sucks for this very reason.
I really enjoy that you talk through every step. I watch other similar channels, but they're always just gestures at most. This reminds me of this old tony, but with metal! (and less jawbreaker references)
You know you have to get this thing up on Ebay and make another one since it needed to be 2-3% bigger. Let me know when the auction starts! Cool project.
No, there's definite improved utility from having it cast in bronze. PLA isn't food safe, so you shouldn't use it for utensils like this, and his bronze measuring cube can go in the dishwasher! Plus of course it looks way more stylish
i have no idea how safe PLA is, but i suppose there are other printable materials which are food safe. but you are absolutely right to love it. it's awesome. @@HaralHeisto
Great video. Makes me want to build another furnace and start casting again! Just curious, did you print the measuring cup slightly oversized to compensate for shrinkage?
@@NeonThoughtBox hahaha that’s hilarious! I was just curious, but going back and reading my comment now makes me feel like such a casting snob haha. Totally didn’t mean it that way. Sorry Seth! Good luck with your brownies…
What % of shrinkage is there when the metal cools off, and how come the ceramic shell doesn’t come off more easily if it’s actually a different size to the casting?
I'd think a vibratory tumbler would be better as the polishing media would be in contact with the entire part constantly, unlike a rotary tumbler. I don't think a rotary tumbler could even get media into the deep crevices to polish them at all.
@@supergiantbubbles If you used only large media you would be correct but rotary tumblers work with anything from pebble-sized media to talc sized and paste type media. Second, you can mix media size in a rotary but not a vib, the small particles just fall to the bottom in a vib, but not in a rotary. A mix of large and small media would have done the sandblasting and polishing steps in one process but only in a tumbler. 👍
You have a sandblaster so maybe give walnut shell a try for polishing. My understanding is that it's aggressive enough to polish, but not so aggressive as to damage the part. It's something I've been looking into for my own sandblaster.
Every time I watch one of these lost PLA videos, my dumb ass hears "cake furnace" and then a few seconds later I see the furnace and remember it's a keg.
I really wish you had a webshop? I’m sure your puzzles etc could be a nice little business. I would certainly buy some of your work. I love it. Thanks for the videos.
Great video and loved the idea of using that slurry. Cube turned out pretty cool. In fact, am ordering one from Amazon to get rid of my crappy collection of measuring spoons and 1 cup to 1/4 cup measurements. Keeping my Pyrex 2, 4 and 8 cup sizes. Thank you.
Extraordinary job. A vibe finisher might be the answer to polishing it. I have one where we use little triangular stones in it about 1/4 inch in size. These were chosen to have sharp points and corners to get into inside corners. We use it for all sorts of polishing and deburring. All operations take a few hours. If you want to send me a sample I would be glad to try it for you no charge of course. I don't do casting but enjoy your excellent videos. JY
I am a plant supervisor for a investment casting fan as well as my father is the owner. This is exactly what we do, except we focus more of cost savings and cheaper materials.
Hey Seth i love watching your videos i can see you put time and effort into your videos Thanks. I sure hope UA-cam appreciate your effort, like me and others youtubes, youtube was not worth or TIME and effort even with millions of views. Fortunately there is other platforms withs appreciate the work we put into videos. ;) and i sure hope you not only upload on youtube. AlumiTube
Hello! Good to hear from you! I’ve started really trying. I’m starting to finally see results on this platform thankfully. What platforms do you find better?
Looks sick! Do you turn the mold to the sides after your pour in the molten metal? Or did it nicely go in by itself and covered all the corners and details? I'm surprised by the high definition of the models in this video and some of your previous ones as well. I always thought that keeping such fine details is incredibly difficult, but you make it look easy!
red liquid metal is just mesmerizing to look at try adding phosphorus for less oxidation during casting and 1 - 1,5% lead for better castability (+ food safe clear coat finish) let the casting cool on its own, it reduces stress and prevents cracking and get some propper shoes :D
Would be curious to know just how much plastic you melt out vs burn out, would be easy to calculate by weight. Glad you're conscious enough to do it this way.
By no means am I qualified to say anything because I've ever done anything like this but my first thought about that shell being difficult to remove was if perhaps you sanded down some of the 3D printing layers to reduce surface area and thus making it easier to remove from the metal. Just a thought, could be wrong though.
If you're interested in any of the tools or equipment I use and you want to help support the channel then don't forget to check out some of the affiliate links in the video description. Thank you for the support!
You should buy a rock tumbler/ polisher. That would work great.
Very good idea
But it takes so long to get polished rocks :(
Or build one!
@@maximeduchalet4662 ok but I'm expecting him to alloy gear metal forge it, then hob the gears.
a brass tumbler/clearer for reloading would probably work well too.
I did bronze casting in college - incredibly satisfying, but a lot of work. We used the lost-wax process (cire-perdue). This 3D printing method looks fascinating.
I went to college so long ago I think bronze hadn't been invented yet. :)
"80 thousandths of an inch" sounds so complicated compared to 2 millimeters.
It always gets me. Thinking if people can really imagine some tiny thousandths of something.
Either way, super cool project. I saw this measuring cup being used by the "as seen on TV" guy.
It didn't seem overly practical, at least in the way he used it.
But making a bronze version is pretty awesome 👍 and the quality of your casting is superb.
or just 8% of an inch. Do basic conversions escape your capacity? Lol
@@THESLlCK Or maybe just 2 mm. Do basic units escape your capacity?
@@JuanCLeal complain more
I suppose thou(sandths of an inch) is a weird unit if you don't hang around US machinists, but there's a few intuits for it: a hair is a few thou, a playing card is about 10 or 12, the wire in a paper clip, something like 40 thou. While no one could feel a difference in width between 40 thou and 41, it's likely that you'd feel a burr 1 thou high on an otherwise smooth surface. Imagine a fine hair on a glass plate. 1 inch is not really long, but its long enough that 1 thousandth of an inch is tiny, but in some contexts, still very much perceptible. Just my 2c. Have a good one.
@@THESLlCK I prepared this bucket of ice cold water for you 🪣 That burn has to sting pretty bad.
Thanks for tuning in to another installment of, “words I didn’t know before!”:
1. Sprue: A channel or funnel through which metal or plastic is poured into a mold.
2. Vitrify: To convert (something) into glass or a glasslike substance, typically by exposure to heat.
3. Lost PLA Method: The model is placed in a plaster mold and the mold is heated until the wax liquefies and flows out of a hole in the bottom (hence the “lost-wax” part of lost-wax casting). Liquid metal is then poured into the mold, which flows into the imprint of the design left in the baked plaster.
Tune in next week to find out precisely where my vocabulary was lacking (or REMEDIAL for the kids following along at home!)!
Nice I also never know this word
youll learn a lot more if you stay in these spaces.
I did know vitrify, not sure why, but the other 2 were new to me, as well.
ok
...as a Kitchen gadget groupie, I am thunderstruck!!! Thank you for this
You have created something that your descendants can still marvel at, with your name on it and a small inscription, they can still remember you many years later.
Was the measurement still accurate?
I worked in a bronze foundry years ago and I would have been send home when wearing those shoes!
We wore wooden shoes only as they can be kicked off and offer some seconds before burning through when your cast leaks and liquid metal spills out.
Cool shape, thanks for sharing, stay safe.
Never heard of using wooden shoes.
What was your favorite part of working there? Sounds interesting :)
Which measurement would it be accurate to? Tablespoon to ml isn't accurate in the first place.
@@edwardssistershands Well one tablespoon is 14.786788602728 ml. I don't know any recipe in the kitchen that would be measured with such a device that is ruined by 0.2132114 ml of something that inaccuracy you have with pretty much any kitchen measure anyways. Especially by volume.
@@carpediem5232 Compounding errors :)
As a cook, I love this so much. It's definitely functional art. I would definitely use this cube.
It measures well but is too easy to spill liquid.
I was thinking about how impractical and bulky this would be in the kitchen.
Stacking measuring cups are far more practical but this looks really cool.
@@AquarianNomadic why do you need multiples of a measuring jar or cup? one is not enough?
@@jurekmc There's 2 types of measuring cup.
Dry and wet.
@@AquarianNomadic with plates, a scale and a measuring jar(idk how to call it, sorry for bad english) its more than enough for me but i get where you are coming from.
Once metal 3D printing becomes more publicly available people are gonna go crazy with their inventions and projects
Ha, that camera magic with the gloves was great! Nice casting, too. I love functional projects.
Man, I've never seen someone use a slurry like that. Definitely going to look into it when I get back into casting. I'm already stocking up on old radiators and such
While I don't think it would have worked with this project, I really like what BigstackD does with Petrobond. If you haven't seen his channel, check it out. It's awesome to me that for a channel where no one says a word, the dude is freaking hilarious! If you haven't seen the channel, check it out!😎🤙
@@TheRisskee he doesnt seem to like doing lost castings, Im not sure why. He does the odd styrofoam lost casting I guess. The petrabond seems really finicky and I feel like his castings never turn out quite this perfect. My theory being that the molds are inherently forced to be cold, so the metal doesnt cool evenly. Love that Aussie tho
Suspendaslurry is AMAZING. But it is expensive. I just bought some but I had to hide it and the price from my wife. Shipping was about $300.
looks great, i printed and used some of these myself. for the finish, i really liked how smooth you got the bottom with the large disc sander. i would do the same with each of the sides. with their rims all the same smooth, shiny metal, it would contrast quite nicely to the rest. and you could even get a more elegant look if you sand the rims until the edges are pointy
drive.google.com/file/d/1_DNK01kUjizxYDQe_xFU9l_cgUkali9b/view
Also be an interesting contrast if the insides were highly polished, [vibratory medium polisher, perhaps ?] and the base and outer corners were left matt finish.
That would be perhaps a little easier to clean if used for actual cooking measurements
The detail you capture in your castings is amazing. Thanks for sharing.
The detail preserved by the casting is nuts! If you had told me that was bronze color filament, I'd have believed it.
That Sir is piece of art. Any top baker would be proud to have that working piece of art in their kitchen.
Beautiful. The fact that it caught even the printed lines is amazing
best chef paperweight ever!!
I love the pour the detail is so perfect you could see the over spill of glue where you joined the 2 parts
There's just something about you that's so cool. I bet you're a really neat person
Ngl that transition of putting on the gloves was really smooth
Don't be so hard on your self, you did a great job on this. I have not seen anyone do it better so I think that is a great way of scaling how well you did. Thanks for the video, always fun to see what your going to work on next.
This was a very satisfying video to watch, and I really like how the cube came out at the end. Kudos to you Mr. Robinson.
You ever thought about an acid bath, it'll clean it up and may help get rid of some lay lines and tool marks before you polish the pieces up. I love these craftsmanship channels. Keep up the good work
I'm a 3D printing and metalworking mechanical engineer and I learned stuff in this video, thanks! Great work on your casting! Great to see some professional-level technique used in a UA-cam casting vid.
Personally I might have smoothed the 3D print a little first... but that would have been a PITA and you did a great job anyway.
To remove the ceramic shells - I've actually re-furnaced my pieces after doing the initial cleanup. The shell can fall off in circumstances like that, due to differential expansion. Might have saved you some sandblasting time.
It's incredible to see how you made those. Somehow this kind of videos are very calming.
They are, aren't they.
Whoa, this looks sooo cool 🥰 I got a 3D - printer for architecture model printing and that model itself had been on my list for a while as well . I didn't even know one could use it along with ceramic slurry to make metal castings, that's so cool to see!
that imperfect surface finish to me makes it look better
Having the ceramic shell helps a lot. Not only in allowing the original PLA template to melt out and leave a perfect negative void, but also with the pouring of the cast as it's perfectly able to withstand the heat/pressure of the molten alloy at the temperature required for it to remain liquid long enough to fill every space. The results speak for themselves.
Thanks for adding the conversion of temperature in °C as text once. I would appreciate it for the burnout and melt-temperature of the PLA as well.
He shows celsius on the thermometer in the other cases
@@angrydragonslayer I did not see it when I watched the video. Could be more obvious but yes it is there.
@@Flederratte yeah.... pretty easily missed but that's life when looking at someone else doing something
on a sidenote, trying to learn smithing from an old-fashioned smith sucks for this very reason.
Wow, huge improvement to the typical lost pla castings I've seen.
I really enjoy that you talk through every step. I watch other similar channels, but they're always just gestures at most. This reminds me of this old tony, but with metal! (and less jawbreaker references)
You know you have to get this thing up on Ebay and make another one since it needed to be 2-3% bigger. Let me know when the auction starts! Cool project.
That's a beautiful thing you did, regardless of the fact that for the task of measuring, the printed cube was already perfect as is.
No, there's definite improved utility from having it cast in bronze. PLA isn't food safe, so you shouldn't use it for utensils like this, and his bronze measuring cube can go in the dishwasher! Plus of course it looks way more stylish
i have no idea how safe PLA is, but i suppose there are other printable materials which are food safe.
but you are absolutely right to love it. it's awesome.
@@HaralHeisto
the ceramic stuff when liquid seems delicious ngl
Great video. Makes me want to build another furnace and start casting again! Just curious, did you print the measuring cup slightly oversized to compensate for shrinkage?
Forever cursed to make slightly fewer brownies!
@@NeonThoughtBox hahaha that’s hilarious! I was just curious, but going back and reading my comment now makes me feel like such a casting snob haha. Totally didn’t mean it that way. Sorry Seth! Good luck with your brownies…
What % of shrinkage is there when the metal cools off, and how come the ceramic shell doesn’t come off more easily if it’s actually a different size to the casting?
@@thechumpsbeendumped.7797 ceramic shell shrinks as well and even more during firing. It is basically sintering
@@thechumpsbeendumped.7797 Guess it depends on the specific alloy used.
I'm glad you tried too bc it's a pretty cool measuring device.
That's a job for a rotary tumbler if ever I saw one, great job.
I'd think a vibratory tumbler would be better as the polishing media would be in contact with the entire part constantly, unlike a rotary tumbler. I don't think a rotary tumbler could even get media into the deep crevices to polish them at all.
@@supergiantbubbles If you used only large media you would be correct but rotary tumblers work with anything from pebble-sized media to talc sized and paste type media.
Second, you can mix media size in a rotary but not a vib, the small particles just fall to the bottom in a vib, but not in a rotary.
A mix of large and small media would have done the sandblasting and polishing steps in one process but only in a tumbler. 👍
You have a sandblaster so maybe give walnut shell a try for polishing. My understanding is that it's aggressive enough to polish, but not so aggressive as to damage the part. It's something I've been looking into for my own sandblaster.
I just loved this casting method! Thank you for sharing!!!
The glove trick was sweet.
Love it! i guess lost pla could be done. but this is the first time I watch it being done.
2:52 forbidden tempura
Maaaan that C U B E turned out beautifull
you are no joke, the cast master
Always had a fascination for casting
Every time I watch one of these lost PLA videos, my dumb ass hears "cake furnace" and then a few seconds later I see the furnace and remember it's a keg.
I heard that too, and I didn't question it. I don't know the jargon. Thanks for setting me straight.
That's impressive. Surprised how well the letters showed up
Looks great. Makes me miss metal pouring and metal works I did in college.
A very professional finish!
As a cook, you get 2 thumbs up form me!
Also, your lost PLA & Suspendaslurry videos are most awesome!
I'd recommend sanding away the printing finish from the 3D print first next time to get a smooth effect on your bronze, well done!!
Thank you. You're a Master craftsman. Keep up the good work!
That was absolutely totally awesome!
What a lovely object.
Vato, eres un artista, uno bueno
Another beautiful casting well done! Thank you for clearly explaining the process
I really wish you had a webshop? I’m sure your puzzles etc could be a nice little business. I would certainly buy some of your work. I love it. Thanks for the videos.
Truly exceptional work your PLA casting is becoming more exquisite every video you know what they say practice makes perfect 👍🏻👍🏻👍🏻👍🏻😊😊😊😊
Seeing you use your 3D printer makes me want to play some Astroneer!!! Thanks!!! 😄
Great video and loved the idea of using that slurry. Cube turned out pretty cool. In fact, am ordering one from Amazon to get rid of my crappy collection of measuring spoons and 1 cup to 1/4 cup measurements. Keeping my Pyrex 2, 4 and 8 cup sizes. Thank you.
Extraordinary job. A vibe finisher might be the answer to polishing it. I have one where we use little triangular stones in it about 1/4 inch in size. These were chosen to have sharp points and corners to get into inside corners. We use it for all sorts of polishing and deburring. All operations take a few hours. If you want to send me a sample I would be glad to try it for you no charge of course. I don't do casting but enjoy your excellent videos. JY
A large vibratory tumbler should be on your shopping list. With the correct media you could polish then entire part inside and out in one go.
Literally great work .
Cool device and idea. Thanks for sharing.
Weekend Stuff
That really came out freakin awesome
I got a serious suggestion for your polishing issue it'll mean a media swap in your sandblaster, try crushed nut hauls/shells.
Wow!! That is an amazing device!!
That is bad ass! Would love one of them.
I am a plant supervisor for a investment casting fan as well as my father is the owner. This is exactly what we do, except we focus more of cost savings and cheaper materials.
Hey Seth i love watching your videos i can see you put time and effort into your videos Thanks. I sure hope UA-cam appreciate your effort, like me and others youtubes, youtube was not worth or TIME and effort even with millions of views. Fortunately there is other platforms withs appreciate the work we put into videos. ;) and i sure hope you not only upload on youtube. AlumiTube
Hello! Good to hear from you! I’ve started really trying. I’m starting to finally see results on this platform thankfully. What platforms do you find better?
I was just watching with the sound low, I'm going to watch again and I'm thinking how nice this would be to cast in silver.
Actually this Cube it’s difficult design you do great job 👏🏽👏🏽👏🏽
Looks sick! Do you turn the mold to the sides after your pour in the molten metal? Or did it nicely go in by itself and covered all the corners and details? I'm surprised by the high definition of the models in this video and some of your previous ones as well. I always thought that keeping such fine details is incredibly difficult, but you make it look easy!
Thank you! No, I didn't turn the mold at all. The metal was fluid enough to completely fill it. Ceramic shell is amazing stuff!
@@robinson-foundry ery noic m8
drive.google.com/file/d/1_DNK01kUjizxYDQe_xFU9l_cgUkali9b/view
That's so perfect cast.👍👍👍
I like how the furnace is a repurposed keg
Great video, you could smooth finished the 3D printed part and the finish of the bronze cube would be awesome!
Love the keg forge! #innovation
That slurry is some forbidden eggnog, I swear.
This is a fascinating object on many levels. Thanks for sharing it.
the perfect cube is the oddest shape. this dude
I don't know if it'd help in the future but if you are using cura for the 3d slicing, it has a mould mode and will produce an inverted print.
That's an impressive turnout, from what I hear and have seen it is hard to get any metal to look as good as that
red liquid metal is just mesmerizing to look at
try adding phosphorus for less oxidation during casting and 1 - 1,5% lead for better castability (+ food safe clear coat finish)
let the casting cool on its own, it reduces stress and prevents cracking
and get some propper shoes :D
What a great idea
Super cool design! Way to go!!!
👍 like it. You have the skills, foundry and a place to do that.
Very nice. But how accurate is it? Did you measure the volumes afterwards?
This is amazingly nice! Good job bro 👏
Wow! This is amazing!
멋진 영상 잘 봤습니다.
왼쪽은 요리에서 쓸 도구.
오른쪽은 장식품으로 끝나겠네요.
쇠덩이가 이쁘긴한데 무거워서 실제 요리하면서 저걸 쓰려면 힘들거에요.
Excellent job.
THAT was way cool!!
I work in a huge foundry making jet engine parts more specifically I work in wax with huge presses! I love your stuff tho :)
Would be curious to know just how much plastic you melt out vs burn out, would be easy to calculate by weight. Glad you're conscious enough to do it this way.
Nice. Thanks.🤩👍 Thailand.
Great job on that!
I would purchase this and many more of your other projects awesome job
I didnt know this was a thing, but now that i know, i wanna do it aswell!
By no means am I qualified to say anything because I've ever done anything like this but my first thought about that shell being difficult to remove was if perhaps you sanded down some of the 3D printing layers to reduce surface area and thus making it easier to remove from the metal. Just a thought, could be wrong though.
Turned out great. good job