Metal Casting Zone

I have a homework about casting. We need to design a casting process to produce 350 outdoor signs. They all must have different numbers on it. And these numbers must be 3 digits ( like 110,111,225,....). Basically I plan to make signs 200mm x 400mm rectangular and 10mm thick. And numbers will be on it.

But I need to be given some advices about what molding type, and what kind of material I should use. I thought aluminium may be better and I can use sand casting. But I'm not sure about these. What should I use for these parts?

And I don't know how I can make 350 different molds which have different numbers on it. Should I use cores for numbers? What kind of cores should they be?

I'll be so happy if you help me about those. Thank you.

I would use MDF it would be easy to cut for the patterns. When you do your numbers
put a alignment pin at the top and bottom at the centerline of the number, then make your back plate with the locateing holes in it that way all you will have to do is change
one number at a time and remold.

Forgot, to get the numbers to look right print them out on the computer then put a thin coat of elmers glue on the MDF place the paper with the number you printed out on it on the glue and squeegee out the excess with a credit card. You can then cut out the number nice and easy. Neat trick huh?

thank you for advices. what do you suggest for the thickness? I'm not sure about it too.

That all depends on what you want your finished project to look like, but try to stay over 1/4" think at its thinnest point. Are you actually going to cast these or is this just a theesis ??

just thesis

do you think sand casting is OK for it? and aluminium as material?

bronze would be best since it is outdoors, better corrosion resistance. would last a life time. theft however may be an issue.

sandcasting would be easiest for a small production run.
Make up one back plate then 3 of each number in MDF, Coat the MDF with shellack when finished.

OK. Should numbers in drag, and back plate in cope? or should it be the opposite? and what about riser and pouring cup etc.?

I ask lots of questions, I'm sorry about that. But I'm rookie I havent thought about these before thank you for your help

OK give me a minute going to take some typing to explain this one....