there was an article in r&c a while back on how to reproduce tail lights, and i need to know about the mold material it was some kind of silicone i think, does anyone have a clue as to what im talking about?
Yes, I remember the article (about a year + change ago or was that SR), but I don't remember the specs, will look for it.
i think eastwood makes a kit to repo rubber parts. i found this: http://www.eng-tips.com/viewthread.cfm?qid=117391&page=1 http://www.eastwoodco.com/shopping/...?itemID=2132&itemType=PRODUCT&iProductID=2132
look at a place called IASCO. Industrial art supply company. I have gotten mold making rubber there. I forget where else i have gotten it but ill look through some old notes. I took a few cl***es in art school in mold making and casting and might be able to help you out.
You're in luck, I build model human hearts and I make my own molds. I use RTV Urethane from Tap Plastics. Also, Smooth On is an excellent supplier. Check them out and ask any questions...make sure you get mold release too!
I swear any one that does ANY profession or hobby is on the HAMB....which is good since we can pull in all this info from different areas!!!
i saw some stuff called alumilite, or something like that. ummm... http://www.alumilite.com/ there, is that it? i want to try it. trey
Allumilite is good, but I'd go with smooth-on. If you use silicone mold material, then you usually don't need a release agent. My .02
I've been trying to get a decent casting off a parking lens with the smooth on products clear resin. To get it bubble free you need to make a pressure tank. If I can ever dig myself out of brokeness I'll do a tech on it. I already have the mold done. Im thinking plexi epoxy and my compressor should do it.
The high end cast guys use an autoclave (va***e chamber). The low tech method is pour your mold and set it on top of your frig or running cloths dryer, the vibration will help the bubbles rise to the top of the casting. If you create a sprue/riser or extra depth in the mold the excess may be trimmed off along with the bubbles. Slower kicking resins also help to get out the bubbles.
If you make a sprue for it make sure you taper the hole so that you can pull the excess out. We usually do a 1/3 taper, with the bigger end towards the part. If you are going to do a lot of molding a simple injection system is a plunger set up. If you want to do that I can go into detail, it's easy to do, with minimal machining required
The clear resin is a ***** even with a 8 hour cure time it still had bubbles through out every inch of it. My resin suplier told me to do the pressure deal.
Becarefull using the wrong RTV silicone with the wrong clear resing. There are 2 types of RTV Tin based and Platinum based. One of the types doen't work well with clear resing and will not let it cure. The other will cure like normal casring resing. Ask you plastics supllier for details on this. Silpak is about the most knowledgeable pl***tic supplier I know. http://www.silpak.com/ Some people that make their own lenses vacuum form them instead of casting them.
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