casting project

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casting project

Author	Message
MattN34	MattN34 posted 12 Years Ago HOT Topic Details
Group: Forum Members Posts: 6, Visits: 76	hi i have taken on an aluminium casting project for my engineering college project and possibly make a bit of money from it. my plan is to produce cast aluminium car fuel caps. (like the classic aston ones) my plan was to use RTV silicone to produce a resin copy of an existing cap i have borrowed and then use that to form sand moulds to cast with. my reason for making a resin copy is that it will need alteration (hole filling in etc.) before i can make the sand mould. what i would like to know is is rtv silicone and casting resin the best way to achieve this is there anything cheaper than RTV i can use as I'm on a tight budget and have calculated i will need 5 L of RTV to achieve this any info or advice would be much appreciated thanks
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Pembroke	Pembroke posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 5, Visits: 87	Hi Matt, Well no one else has answered so I will make an attempt although I'm no expert. First off have you contacted Aston Martin to find out how the original was made? If not don't mention you're copying it just that you're an engineering student. It may be that they were originally machined from a solid block of aluminium rather than cast as I would imagine that a casting would still need to be machined to a certain extent to make mating surfaces true. If Aston did cast the originals I'd guess the patterns were turned and carved from wood. Could you do something like that? As another thought does your college have access to a CAD system and a 3D printer? That may be a cheaper way of making your pattern. If you're forced to use the RTV and casting method then can the cap be broken down into smaller components to make casting easier. Without seeing it, the tube into the petrol tank, the cap and some sort of latch for instance. Only other thought is could you use the RTV to make a layer approx 1 cm thick over the cap, then use some other cheaper material to support the shape of the RTV while you do the castings. If you made the RTV into a regular shape around the cap then you could use say plaster of paris to support the mould while the casting was hardening and it should be possible to remove the RTV with the casting still inside from the plaster then remove the casting from the RTV mould. You can then cast another cap as you will be able to get at least 4 possibly 6 into one sand cast frame. Hope that is of some help?
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brasco	brasco posted 11 Years Ago HOT Post Details
Group: Forum Members Posts: 192, Visits: 305	well epoxy is perfect for casting. it can be drilled and tapped and machined. make SURE you get an epoxy made for this application tho. casting and silicone rubber is good for a mold, but you need a way to vac out the air bubbles in it(degassing). make a mold i am lucky this company has an outlet and warehouse near me. i love hanging out and talking with teh manager, he is a mountain of good information. but most all this applies with any product line.. i have a hockey puck sized piece of epoxy and it is solid. no cracks and no softness. they say theirs can be drilled and tapped. and machined. i think their tutorials are good as well. and a large variety of materials, from hobby to special effects and concrete casting even. scott CarbonFiberCreations
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