Making a Measuring Cube - EXTREME MEASURES - bronze metal casting at home - 3d Printing Lost PLA

welcome to robinson foundry my name's seth robinson and in this video i'll be turning this clever 3d printed measuring cube into solid bronze using the lost pla method i found this cool measuring cube model online and i thought it would make for a really great casting however i knew it would be a challenge take a look at this cross section the thinnest sections are only 80 thousandths of an inch thick or 2 millimeters thin sections can be difficult to cast because the thinner the part is the less heat the molten metal can retain causing it to solidify before the mold is completely filled i started this project by 3d printing the measuring cube using a plastic called pla pla works great for this casting process because of its relatively low melting point and ability to be burned away without leaving any ash behind i also printed this sprue which will act as a funnel helping me to pour the metal into the mold i glued the sprue and measuring cube together using hot glue and then glued on some pieces of pla filament to act as events this stuff is called suspend a slurry it's essentially a liquid ceramic that is used to create strong ceramic shell molds for metal casting after filling in the text with a brush i carefully dip the model into the slurry doing my best to avoid trapping air bubbles on the surface of the model the first few coats are the most important as this is where the fine detail is captured my goal was to slowly build up a thick shell by coating the model with slurry about 10 times after the first two coats i sprinkled each subsequent coat with silica sand and allowed it to dry before adding another normally after the fourth coat i wrap the entire shell with thin wire which helps reinforce the shell preventing it from cracking however i didn't do that this time because the measuring cube is a very odd shape making it very difficult to properly wrap i allowed the shell to fully dry for a few days and then placed it in my kiln to burn away the plastic and turn the shell into ceramic i turned on the kiln and over the next few hours i slowly brought up the temperature to about 500 degrees fahrenheit which is the temperature at which the pla plastic starts to melt out of the shell at this point i was able to remove the vast majority of the plastic instead of just burning it away then i cranked up the temperature to around 1 500 degrees fahrenheit this evitrified the shell turning it into a ceramic that can withstand the temperature of molten bronze with the shells ready to be filled with metal it was time to fire up my homemade cake furnace and melt some bronze for this casting i used some bronze that i had left over from previous projects this bronze alloy contains roughly 90 copper and ten percent tin it took about thirty minutes to melt this amount by the way if you're interested in checking out any of the products used in this video i'll include affiliate links to most of them in the description once the metal was melted i added a small piece of aluminum to add strength and improve the corrosion resistance of the bronze alloy i let the bronze heat up to about 2200 degrees fahrenheit to make sure that it was liquid enough to fill the thin walls of the mold then i removed the shell from the kiln and poured in the metal as quickly as possible i couldn't resist throwing a couple ice cubes on the metal to watch them disappear then i carefully submerged the mold in water for a while to cool it down unfortunately this does nothing to soften the shell but it does help cut down on the amount of dust produced when the shell is broken off then i started to chip off the shell with a hammer but because of the shape of the casting i hardly got any of it off removing these shells can be really difficult especially if there are a lot of indentations on castings like this one [Music] fortunately i have a sandblaster which made the job a lot easier but it still took about two hours to remove all of it after removing the shell i was happy to see that the mold filled out properly and the casting looked good next i snipped off the vents and used a hacksaw to remove the sprue [Music] then using my large disc sander i carefully sanded the bottom smooth i actually had a hard time polishing this measuring cube as the little pockets made it very difficult to use anything other than wire brushes and even then i still had a hard time reaching certain areas well here it is i'm really happy with how this turned out i was a little apprehensive to try and cast this cube because of the thin walls i mentioned but i'm glad i tried because it ended up looking great i love using ceramic slurry to cast objects like this look at how much detail was captured you can see all the individual layer lines from the printing process the castings not without its flaws you can see that the surface finish is poor in some areas which i believe is from adding the small amount of aluminum to the bronze but i still think it turned out great and i'm glad i tried i hope you enjoyed watching this video and if you did please give it a thumbs up tell me what you think in the comments subscribe for future projects and take a look at some of my other videos thanks for watching

Channel: Robinson Foundry

Views: 892,489

Keywords: lost pla casting, lost pla, lost pla casting aluminum, lost pla casting from 3d prints, lost wax, lost pla 3d print to metal casting, pla, lost, lost wax casting, lost pla metal casting, lost pla casting brass, lost pla casting process, how to lost pla cast aluminum, lost pla casting home foundry, lost pla method, lost pla process, metal casting lost pla, lost pla casting bronze, lost pla casting a benchy, lost foam, lost pla casting an eagle, lost pla casting tutorial

Id: zGWNJxqSd-A

Length: 9min 26sec (566 seconds)

Published: Sun Aug 22 2021