So just what is pot metal??

[studiog]

Since pot metal is so prevalent in our old Vettes I did a search to see just what the stuff really is and why some people cringe at the mention of it. I'm sure some of you already know this but some of you like me may not. Seems the term pot metal comes from the fact that it can be melted in a cast iron pot used at foundaries for just this purpose. It is also called white metal. It is an alloy, usually of lead and copper but can also contain other elements such as tin and zinc. It casts at a low temperature thus having minimal shrinkage. The stuff melts at about 900°... careful with that torch! It has low structural strength, is brittle and is very porous which allows oxidation to seep in. Because of this it tends to weaken and even crack over time. Good news is that it is suppose to be easy to repair by an experienced welder and can also be repaired with allumalloy.

Hope this is helpful.

 

[Larry Shermak]

Pot Metal

Studio, The term probably came from the process which the metal was melted in a cast iron pot. I'm a moldmaker & I sure don't like the term "pot metal". It makes the quality sound poor. All die cast dies are made of steel and injected with either aluminum, zinc or magnesium. In the case of some decorative parts such as trim or mirrors, many of them were cast with zinc. Some of the processes today have improved to take the porosity (or holes) out of the part. As far as welding them, not much hope there......

 

[studiog]

Studio, The term probably came from the process which the metal was melted in a cast iron pot. I'm a moldmaker & I sure don't like the term "pot metal". It makes the quality sound poor. All die cast dies are made of steel and injected with either aluminum, zinc or magnesium. In the case of some decorative parts such as trim or mirrors, many of them were cast with zinc. Some of the processes today have improved to take the porosity (or holes) out of the part. As far as welding them, not much hope there......

Thanks Larry.

 

[bossvette]

I too have worked on my share of Die Cast Dies a long time ago. The GM plant I worked at made door handles and trim parts the alloy was monitored quite closely even back then.
I do remember that it is not easily repaired, but usually remelted and cast again.

 

[Vette66AirCoupe]

So just what is pot metal??

Metal that gives you a buzz??

 

[BarryK]

well, if it is than don't go driving in one of the vettes after working with it Terry

 

[Tempus_Fugit]

It is usually zinc, or an alloy of Zinc and Aluminum.

John

well, if it is than don't go driving in one of the vettes after working with it Terry

 

[cbernhardt]

I'm a moldmaker & I sure don't like the term "pot metal". .

Larry:
Since you are a mold maker how feasible would it be to cast new C1 door/window posts in some other material, such as aluminum?

Charles

 

[studiog]

Larry:
Since you are a mold maker how feasible would it be to cast new C1 door/window posts in some other material, such as aluminum?

Charles

Great question. Seems like there is a need for good repros of these parts, especially since the tabs are so frequently broken on the windshield posts.

 

[Larry Shermak]

Aluminum windshield post

I could make the die & I'll do some checking on what it would take to make castings - I just wonder about the quanity involved. Larry

 

[vintagecorvette]

I have spotlight brackets for 1950's cars made as well as some other parts. I looked into having windshield posts as well as some other parts made, the problem that the foundry had was the shrinkage that occurs. The guy does lost of custom work and he worried that the frames might not cast up well enough to fit the windshield because of the shrinkage. oWEN

 

[wapaugh]

Larry,

Luckily my tabs are intact, but I do have a lot of pitting on both the door and windshield posts. I am hoping these pits can be filled and the posts rechromed, but if not I could be your first customer.

 

[cbernhardt]

I could make the die & I'll do some checking on what it would take to make castings - I just wonder about the quanity involved. Larry

Larry:
I have never done any metal casting. Could you briefly describe the process and what materials are used for the molds? What would be your guess on the cost of casting some prototype (sample) door or windshield posts? What material would be best for the posts? If the posts could be cast in aluminum or some other light weight material, I would be interested in a set just for the weight savings.

Charles