ed4copies
Local Chapter Manager
In this thread: Plastic?
the question was asked, how are the numerous types of plastic blanks different from each other. I gave a short (possibly terse) answer and I was surprised how much interest the thread got.
Our new librarian (and one of my good friends), Wayne suggested that we try to get answers that were "library-worthy" and incorporate this as an article. Honestly, I think that is such a good idea that I am starting a few of these threads and I will incorporate the information into an article for Exotics and make it available to the IAP Library.
Polyester Resin:
Also known as Silmar 41 and other "trade names", including "Castin Craft", and a product from US Composits---someone may have that name and add it here, please.
Polyester resin is "poured in the kitchen or garage", it is a resin that is mixed with a catalyst (usually MEpK). This causes a chemical reaction that is exothermic (gives off heat). The amount of catalyst used will effect the turning characteristics of the final product. The more catalyst, the higher the temp during curing and the more "glass-like" the final product becomes.
Polyester resin can be clear or dyed one or several colors.
When very little catalyst is used, the resulting pen blank is easy to turn and will "peel off in ribbons" with a sharp turning tool. It is very easy to sand and polish, using Micromesh or Novus or buffing.
When a great deal of catalyst is used, one such product is called "Inlace acrylester". This is extremely "chippy", and takes a fair amount of tool control to achieve the "ribbons" turning off. I consider Inlace Acylester one of the most difficult of the plastics to turn successfully, but it does polish EXTREMELY well and the available colors are striking---because the resin sets very quickly, so the colors do not blend, they remain intense.
Again, please contribute YOUR thoughts and experience with polyester resins.
the question was asked, how are the numerous types of plastic blanks different from each other. I gave a short (possibly terse) answer and I was surprised how much interest the thread got.
Our new librarian (and one of my good friends), Wayne suggested that we try to get answers that were "library-worthy" and incorporate this as an article. Honestly, I think that is such a good idea that I am starting a few of these threads and I will incorporate the information into an article for Exotics and make it available to the IAP Library.
Polyester Resin:
Also known as Silmar 41 and other "trade names", including "Castin Craft", and a product from US Composits---someone may have that name and add it here, please.
Polyester resin is "poured in the kitchen or garage", it is a resin that is mixed with a catalyst (usually MEpK). This causes a chemical reaction that is exothermic (gives off heat). The amount of catalyst used will effect the turning characteristics of the final product. The more catalyst, the higher the temp during curing and the more "glass-like" the final product becomes.
Polyester resin can be clear or dyed one or several colors.
When very little catalyst is used, the resulting pen blank is easy to turn and will "peel off in ribbons" with a sharp turning tool. It is very easy to sand and polish, using Micromesh or Novus or buffing.
When a great deal of catalyst is used, one such product is called "Inlace acrylester". This is extremely "chippy", and takes a fair amount of tool control to achieve the "ribbons" turning off. I consider Inlace Acylester one of the most difficult of the plastics to turn successfully, but it does polish EXTREMELY well and the available colors are striking---because the resin sets very quickly, so the colors do not blend, they remain intense.
Again, please contribute YOUR thoughts and experience with polyester resins.