Door Pocket Hinge Breaking Issue

[govols!]

Hey Guys !!
In getting ready for a concours, we have encountered breaking several plastic hinges. They are so thin in the middle and are not very flexible. Does anyone have this problem ?? Any vendors have better ones than others ?? Thanks !!

[Scott A]

I would have considered using leather as my hinge....and maybe I would have considered to add a thin layer of leather sandwiched with the plastic part.

[govols!]

Good idea, Scott. Any other suggestions ??

[davep]

Hinges of that type are known as living hinges at least in my industry. When molded, the hinge is supposed to be flexed several times while still warm to better align the molecules, but I think this is rarely does in volume production. It also depends on the material. Nylon for example is a condensation polymer that converts the raw materials to long molecules of polymer and water. Think of it as spaghetti with sauce. When molding, the nylon has to be thoroughly dried before melting to prevent bubbles. Right after molding the part must be rehydrated to regain their toughness. One trick may be to soak them in hot water overnight on an annual basis to help keep the plastic stronger. I find that all plastics tend to degrade over time, and 50 years is a very long time for these pieces. If the breaking parts are new, then they are likely poorly molded.

[govols!]

Very good observations, Dave !! Actually, these are new and actually only opened twice, gently, as these have broken before. As I recall, once they spontaneously broke and when we opened the door, dragged over the rubber seal. I wonder if there is just one supplier to all the usual vendors ??

[edmayo]

Might consider harvesting hinges from otherwise bad pockets, at least they would be good old original hinges.