Avoiding Problems when Casting Aluminum
- Thread starter GreenTwin
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Cast Iron Pour No. 15 (continued):
More bearing cap photos.
I used ceramic mold coat for the first time on this casting.
It is alcohol-based, and so you dry the mold with a light propane flaming, then spray on the mold coat, then burn the mold coat off.
The mold coat worked well, and prevented the iron from burning into and adhering to the sand mold.
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More bearing cap photos.
I used ceramic mold coat for the first time on this casting.
It is alcohol-based, and so you dry the mold with a light propane flaming, then spray on the mold coat, then burn the mold coat off.
The mold coat worked well, and prevented the iron from burning into and adhering to the sand mold.
.
Attachments
Cast Iron Pour No. 16 and Aluminum Pour No.24 - Phoenix Casting - 2020:
The Phoenix art casting was an attempt to create and cast something/anything during the COVID debacle, when all the art-iron shows had been cancelled.
The overall meaning of the Phoenix casting to represent how backyard casting would one day rise again after the COVID mess passed, and when casting shows could begin again.
The pattern was 3D printed and had a flat top surface.
I ruined the first pattern by heating and trying to bend it.
The second 3D printed pattern was printed with a curvature to its face.
The multi-color was made by cutting the filament and inserting a new color, during mid-print.
I sketched up the pattern in Solidworks after drinking a lot of coffee (no drugs were used in the creation of this pattern, unless you consider caffine a drug).
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The Phoenix art casting was an attempt to create and cast something/anything during the COVID debacle, when all the art-iron shows had been cancelled.
The overall meaning of the Phoenix casting to represent how backyard casting would one day rise again after the COVID mess passed, and when casting shows could begin again.
The pattern was 3D printed and had a flat top surface.
I ruined the first pattern by heating and trying to bend it.
The second 3D printed pattern was printed with a curvature to its face.
The multi-color was made by cutting the filament and inserting a new color, during mid-print.
I sketched up the pattern in Solidworks after drinking a lot of coffee (no drugs were used in the creation of this pattern, unless you consider caffine a drug).
.
Attachments
Aluminum Pour No.24 - Phoenix Casting - 2020 (continued):
I filled the 2nd pattern a bit to allow it to be pulled from the sand, and then painted it.
I normally use shellac on patterns, which is translucent, and dries very quickly.
I cast an aluminum permanent pattern first.
I used the ceramic mold coat again, and it gave a good surface finish.
The photo shows the raw casting with no finish work or buffing being done to it.
I used an open faced-pour.
Perhaps a bit of shrinkage on the left side lip.
.
I filled the 2nd pattern a bit to allow it to be pulled from the sand, and then painted it.
I normally use shellac on patterns, which is translucent, and dries very quickly.
I cast an aluminum permanent pattern first.
I used the ceramic mold coat again, and it gave a good surface finish.
The photo shows the raw casting with no finish work or buffing being done to it.
I used an open faced-pour.
Perhaps a bit of shrinkage on the left side lip.
.
Attachments
Cast Iron Pour No. 16 - Phoenix Casting - 2020:
The ceramic mold coat was used on the iron castings, and they came out of the mold bright and shiny, as if they had been buffed, with no sand adhesion.
Any residual sand on the casting could be brushed off with a dry paintbrush.
This was a fun experience, and gave me an opportunity to go out and melt/cast some metal.
This was also a 2nd test of the ceramic mold coat with iron.
Ceramic mold coat used on resin-bound molds with iron is also a game changer, as far as the increase in surface quality.
I was really shocked at how clean and shiny the iron castings were when I flipped them over out of the mold.
The only difference between the first and second de-mold photos is I used a dry paintbrush to lightly dust off the castings before taking the second photo. It seems like these castings were buffed, but that is how they came out of the mold (I have witnesses).
.
The ceramic mold coat was used on the iron castings, and they came out of the mold bright and shiny, as if they had been buffed, with no sand adhesion.
Any residual sand on the casting could be brushed off with a dry paintbrush.
This was a fun experience, and gave me an opportunity to go out and melt/cast some metal.
This was also a 2nd test of the ceramic mold coat with iron.
Ceramic mold coat used on resin-bound molds with iron is also a game changer, as far as the increase in surface quality.
I was really shocked at how clean and shiny the iron castings were when I flipped them over out of the mold.
The only difference between the first and second de-mold photos is I used a dry paintbrush to lightly dust off the castings before taking the second photo. It seems like these castings were buffed, but that is how they came out of the mold (I have witnesses).
.
Attachments
Casting Work - Post 2020:
The only other melt attempt I made in 2020 was an attempt to melt 1/2" diameter steel rods in my furnace.
I could get the rods red hot, but there was no way to get to the actual melting point of steel using my oil burner and diesel as a fuel.
I am probably short 200-300 F of the melting point of mild steel, and I would need more heat than that to reach some usable pour temperature.
I had to try to melt steel though, just to see if I could do it.
As I understand it, steel is tricky to cast, for a number of reasons that I don't really understand.
Casting gray iron is very easy compared with casting mild steel.
At the end of 2020, I had an avalanche of work projects hit, and I have yet to catch up with everything that was dumped on me.
These were not projects that I could decline, and so the backyard casting and engine building hobby have gone on the back burner, so to speak.
One day I will get caught up, and the Phoenix will rise again in my backyard.
.
The only other melt attempt I made in 2020 was an attempt to melt 1/2" diameter steel rods in my furnace.
I could get the rods red hot, but there was no way to get to the actual melting point of steel using my oil burner and diesel as a fuel.
I am probably short 200-300 F of the melting point of mild steel, and I would need more heat than that to reach some usable pour temperature.
I had to try to melt steel though, just to see if I could do it.
As I understand it, steel is tricky to cast, for a number of reasons that I don't really understand.
Casting gray iron is very easy compared with casting mild steel.
At the end of 2020, I had an avalanche of work projects hit, and I have yet to catch up with everything that was dumped on me.
These were not projects that I could decline, and so the backyard casting and engine building hobby have gone on the back burner, so to speak.
One day I will get caught up, and the Phoenix will rise again in my backyard.
.
