My experience is based on learning how to restore 1948-1954 automotive plastic colored badges/emblems.of that same time production period . Note the Korean War was ongoing and there were federal material controls which led to some manufacturers using less quality materials. Pot metal would erupt …chrome plating was marginal and I had gold plating which based on $ per ounce is now $ astronomical to find gold platers. Lastly remember that you are working with items made in the 1950s some 50 years later.
1. Go to the car restorers plastic emblem folks..google.Source current manufacturers of similar modern emblems (2-color-3 color- 4 color).Plastics have different formulation and what works for one might not work for others (paint, cleansers,..etc.) . Note often manufactuers outsourced the emblems and used different suppliers @ times.
2. Not knowing the quality of your plastic w/aging construction …hard to provide technical solutions.
3. I learned , by practice and verbal instruction. I had a plastics degreed instructor(commercial plastic based jewerly) who told me this might work, BUT said you do it because of the technical variables. So I had to waste a couple. I learned how to buff with plastic rouge , different wheels compositions and speeds (burning,hazing, etc.).
4. Research Hemmings (*Automobile) articles….Emblemagic.com…….Fiberglassics has similar questions as your OP…www.autorestorermagazine.com/car/plastic.htm
5. The learning is thru the doing. Hope this helps.
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