Guys,
I am trying to learn how to make plastic molded parts. My very first project was the 73 and earlier license light lens.
My process still needs a 2nd round of tweaking, but I was able to produce 3 usable lens which I don't need (I'm keeping 2 for myself). The material is a clear, UV resistant urethane plastic that has max deflection temp rating of 176F (for stability in proximity to a incandescent bulb). I thought that was sufficient but no doubt there are higher temp rated urethanes out there.
I don't know what they are worth to you guys, so offers invited.
I need a second chrome cover and am interested in trades.
John (MA)
(details)
They are the right shape and include the PN and raised Hella logo in good/sharp detail. They are all flawed in that each one has one bubble in the rear "domed" part of the lens. There are also a few micro-bubbles scattered about because I didn't leave the mixed resin in a vacuum chamber long enough to pull all of the air away from the injection nozzle. Hey, my eye sight isn't as good as it was when I was young! I LOOKED ok to me and yes I was wearing my reader glasses.
Anway, this little piece has some deep and complex contours given the thickness of the piece, and the plastic flowing into the mold is trapping one notable air bubble back there (3mm diam.). This is due to my inexperience designing the injection/vent holes. This is completely invisible with the lens installed in the chromed cover. Based on what I learned, I'm sure I can make a new mold with different venting/injection points and make a flawless part. But I'm not sure if it's worth the time and effort given that these 1st parts look perfect once installed.
Note, in the pics, I've not cleaned the mold flash off around the edges of the parts (will be done). But nevertheless they fit perfectly in the OEM housing.
Here's some pictures of a used OEM and some repro parts. If you polish up the repro with some car wax, it'll gloss up nicely. It does not have the exact same refractive index as the original lenses.
I am trying to learn how to make plastic molded parts. My very first project was the 73 and earlier license light lens.
My process still needs a 2nd round of tweaking, but I was able to produce 3 usable lens which I don't need (I'm keeping 2 for myself). The material is a clear, UV resistant urethane plastic that has max deflection temp rating of 176F (for stability in proximity to a incandescent bulb). I thought that was sufficient but no doubt there are higher temp rated urethanes out there.
I don't know what they are worth to you guys, so offers invited.
I need a second chrome cover and am interested in trades.
John (MA)
(details)
They are the right shape and include the PN and raised Hella logo in good/sharp detail. They are all flawed in that each one has one bubble in the rear "domed" part of the lens. There are also a few micro-bubbles scattered about because I didn't leave the mixed resin in a vacuum chamber long enough to pull all of the air away from the injection nozzle. Hey, my eye sight isn't as good as it was when I was young! I LOOKED ok to me and yes I was wearing my reader glasses.
Anway, this little piece has some deep and complex contours given the thickness of the piece, and the plastic flowing into the mold is trapping one notable air bubble back there (3mm diam.). This is due to my inexperience designing the injection/vent holes. This is completely invisible with the lens installed in the chromed cover. Based on what I learned, I'm sure I can make a new mold with different venting/injection points and make a flawless part. But I'm not sure if it's worth the time and effort given that these 1st parts look perfect once installed.
Note, in the pics, I've not cleaned the mold flash off around the edges of the parts (will be done). But nevertheless they fit perfectly in the OEM housing.
Here's some pictures of a used OEM and some repro parts. If you polish up the repro with some car wax, it'll gloss up nicely. It does not have the exact same refractive index as the original lenses.
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