Anyone ever done metal die casting?

[Rook 3]

Looking for ideas/solutions. It would be nice to do metal prop gun replicas in the "Zinc 27" metal, but I have issues with the quality of DIY sand casting.

Has anyone ever done metal die casting? Is that how the cheap all metal airsoft guns are made these days?

Thanks in advance,

Russ

 

[Rook 3]

Wow, nobody?

Okay, how about metal casting other than small parts in silicon moulds?

Russ

 

[Anakin Starkiller]

Wow, nobody?

Okay, how about metal casting other than small parts in silicon moulds?

Russ

The issue with metal die casting is the investment cost in producing a metal die, it is very expensive, and generally cost prohibitive for any low production run. Anything less than 1000 or so.

Some silicon can hold low temp metals, but not aluminum.

There are some short run epoxy mold processes that might benefit your purpose.

Also, you might think about doing a cold cast process.

Dan
Dan

 

[Commander Max]

I'll second that on the die casting, way to expensive for short run parts.

Depending on the parts machining might be cheaper.

Look up guys that do rapid prototyping, there are guys that can do that in metal. I can't help you there, your best bet is to call around. Your in the right part of the country to find somebody that can help you.

 

[Krachenvogel]

Yeah, the die itself for die casting tends to be pretty pricey, plus the setup cost can be prohibitive on short runs. The company I work for buys a few die-cast parts, and it's never cost-effective for us for less than 10,000 parts per year or so. I expect the financial considerations are different on hobby items, but still...

Atemylunch mentioned rapid-prototyping. If you have a 3D CAD model of your part that can be exported to STL or STEP, there are outfits that can make investment cast aluminum parts for you. This isn't especially cheap, either, because it is skilled-labor intensive, but your tooling cost is effectively zero. Also, depending on how they make the pattern, you often end up with that stair-step look on curved or angled surfaces. If you want, I can give you a contact in the Milwaukee area who does this sort of work, but I'm sure there are plenty of sources in Minnesota, what with Stratasys being out there and all. PM me if you're interested.

 

[Rook 3]

I'm already doing cold cast from moulds of my original item. I was considering something a bit more... substantial.

I suppose the real "cost effective" choices are Lost Wax or sand casting. Why do my desires always cost more than my wallet can afford?

Thanks everyone!

Russ

 

[INCOM]

Sand casting is the best way to go. I am assuming the issues of "quality" you have with DIY sand casting are with the finish? If so, remember to make your pattern larger to allow for a machine finished surface and also for shrinkage.

 

[dakota_in_the_sky]

I've been doing a search of my own to make some metal parts. There's a process called spin casting. A master is placed on a silicone pad. The silicone gets squashed with another half to make an upper and lower part. The rubber is then heated until vulcanized. After the master is removed, the mold is placed in a spin caster. The gate is on top. The metal is poured into the gate while the mold is spinning. The hot metal flows into all the cavities, making the part.

The types of metal can vary, but zinc and white metal can be done.

I'm trying to find a place that still does that. There aren't a whole lot of places anymore. There's one in PA that might be a good candidate. I'll let you know if it is successful. There are also places that sell the equipment to do this at home. If you are able to RTV molds, this wouldn't be that much more difficult. Hope this helps.

 

[Rook 3]

Yes, the issues I have with sand casting are exactly as stated. I can't really increase the size of the master because it's a found item.

I too have heard of the metals spincasting. "Heard" about it, but don't really know anything about it.

Do they use a liquid rubber to vulcanize and make the moulds, or a solid/semi-solid?

All my experience has been with RTV (Room Temp Vulcanizing) so baking my silicone would be a new experience.

Thanks everyone!

Russ

 

[dakota_in_the_sky]

It's a solid, probably like clay. Here's a good link that shows the process:

http://www.prototypingrapid.com/page/1427013

Yes, the issues I have with sand casting are exactly as stated. I can't really increase the size of the master because it's a found item.

I too have heard of the metals spincasting. "Heard" about it, but don't really know anything about it.

Do they use a liquid rubber to vulcanize and make the moulds, or a solid/semi-solid?

All my experience has been with RTV (Room Temp Vulcanizing) so baking my silicone would be a new experience.

Thanks everyone!

Russ