What are your everyday thoughts, questions, concerns, successes, and challenges?
Well I'm kind doing the same thing that you are, designing adaptive equipment that is. I've been doing it in my spare time now for about six years. I'm close to getting to the production stage with a couple different products and I've learned that it's very important to research what materials will work best. The different characteristics of the materials that matter are their chemical properties (weight, flexibility, etc.), cost, and availability as well as others. It wasn't clear to me if you said that mounting system was made of that white plastic, but if it is that makes sense to me why he did not have any memory when you loosened the wingnut. I would suggest using a denser more rigid plastic or aluminum. Even steel would work; think about that same type of clamp that you tighten down on a bicycle to hold the seat post in place.
Hey, just throwing this out there... if the clamp on the Top Mount bracket was a two piece the removal issue would be resolved and it could be any material you want. It would just require slotted holes for mounting to the final part. I have considered designing a similar bracket for various attachments as well. I have fabrication background and I'm currently studying for a degree in Drafting Tech.
If you're really serious about doing this you should look into 3-D printing technology. People are doing amazing things with this and it will dramatically decrease your development time and your prototyping costs. I learned 3-D modeling in architecture school and I agree that it's a great tool for people who are disabled. It was the only way I could do my schoolwork and keep up with those A.B.'s. :)
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