The New Super8 Standard & Camera
Moderator: Andreas Wideroe
Why not plastic? The camera does not have to be made totally out of metal, does it? Seagull is a big maker of 35mm still cameras and lenses in china. Thier cost for a typical entry level body is $1 US dollar. I know super 8 cameras are more costly, but that just one example I have specifically experienced.
boohoo wrote:Why not plastic? The camera does not have to be made totally out of metal, does it? Seagull is a big maker of 35mm still cameras and lenses in china. Thier cost for a typical entry level body is $1 US dollar. I know super 8 cameras are more costly, but that just one example I have specifically experienced.
when i say "cutting steel", i'm referring to the molds used to create plastic parts. not a metal camera. it's a generic term which actually includes aluminum tools (aka molds - if you've ever wondered what a "Tool & Dye" maker is, it's a machine shop that usually cuts metal molds for plastic molding processes and cuts metal dyes for plastic extrusion processes).
difference between steel and aluminum is basically a) time to cut the tool and b) life of the tool.
wrt a), time is money and it can take months (usually 12 - 20 weeks depending on geometry and tool complexity) to create the tool from steel; aluminum is softer so it's faster and saves money. but steel is usually preferred because of it's longer lifespan (used for high volume/low cost stuff). injecting molten plastic into the mold requires amazingly high pressure - the machines are rated in "tons" - e.g. 40ton press. the two steel halves come together and are "locked" momentarily in place and the molten plastic is forced in. approx 35 seconds later the halves separate and the parts drop out.
wrt b), longer lifespan is critical to recoup your initial investment. the high pressures involved cause wear on the molds. sometimes steel blocks even crack. obviously aluminum wears much faster, so if you want to invest less in tooling, you need a product that is low volume/high cost first.
thing is, oddly enough, the price differential between steel and aluminum is shrinking. it used to be that making a choice was simple. not so anymore. low-cost Chinese labor (Chinese labor to make tools costs much less than American labor) has dropped both types of tooling cost (that $50K would be much higher in the U.S. - it's one reason why manufacturing went to Asia). in addition, better technology is speeding up toolmaking. some Chinese companies crank out tools in amazing time with the new tech that goes in with new R&D facilties.
add all that up, and what you get is aluminum isn't worth doing for many products - esp consumer goods.
now comes the new stuff. metal-plated epoxy molds. i'm not entirely up-to-date on these, but a while back for testing purposes you could either make rapid-prototype parts (very expensive) or if you needed... say... 100 samples, you could make an epoxy mold that would yield about 100 parts before it died. great for R&D purposes since making such a mold can be done in days. now as rapid-prototyping has gotten better, i'm unsure what's happening with these molds. "growing" parts is easier. not just to fabricate, but to design. designing for the mold process is a b*tch. with RP, you're not constrained by the geometry necessary to either get the plastic to flow or to get the part to drop out of the tool. you can essentially make anything of any shape.
RP is probably the way to go. some companies are using it for expensive stuff. Boeing and Sikorsky for complex air ducting in aircraft; medical companies for custom-fit prosthetics and devices. also the RP process used to be limited to primitive materials but that's changing fast. within ten years this is an option that will come into it's own. and it's a perfect fit for niche items and markets.... like the small gauge community. so while it might not make sense now, it will certainly make sense at some point - provided the film is available and the community is still around.
yes, you can buy the tools (to be specific, to say "design" is to imply you're only getting a bunch of 2D drawings created in 80's CAD software - or worse, which really isn't what you want).
problem is that steel doesn't just sit around for years. it's a commodity. and it's value has been steadily rising. more often than not an old tool is sold for scrap. if not it's likely sitting outside somewhere collecting rust.
problem is that steel doesn't just sit around for years. it's a commodity. and it's value has been steadily rising. more often than not an old tool is sold for scrap. if not it's likely sitting outside somewhere collecting rust.