Re:Ask HN: Resources for “Learning” Manufacturing?
by vt240 on Wednesday January 05, 2022 @02:52PM
(#29814006)
We had very good luck using BJB two part polyurethane for low production (<1000 year) large parts. There's quite a bit of process engineering required, but you can get fantastic results, and relatively fast die cycle times, without breaking the bank.
Re:Ask HN: Resources for “Learning” Manufacturing?
by andi999 on Wednesday January 05, 2022 @03:33PM
(#29814544)
Does BJB have some additives so the PU is non flamable? (ul 94 v2 comes into mind)
Re:Ask HN: Resources for “Learning” Manufacturing?
by vt240 on Wednesday January 05, 2022 @08:53PM
(#29818109)
I believe they do, although it's not a something I have used personally.
They have a pretty comprehensive catalog [1], but like most things with adhesives and resins I would just talk to an application engineer about requirements. Haha, I wish they'd had such a comprehensive catalog when we started working on our parts, because we were left to figure out a lot of it for ourselves.
[1] : https://indd.adobe.com/view/5103906b-5e7b-4b52-9fea-09900d1a...
First, if you'd like to take another step forward, I recommend silicone molding your 3D printed part. You'll need to spend a lot of time sanding/prepping, but you can achieve a surface quality similar to injection molding if done right. Your tooling investment will be well under 15k and you can do small batch runs to test the idea. I've seen some product runs under 1k parts that came out looking flawless and were 100% commercially viable.
You can experiment with the type of silicone you use and the type of polyurethane you pour into the mold. You should be working out all of the question marks here. Things like, strength, durability, weight, feel, aesthetic, and more.
BJB plastics has some great silicone products, awesome customer service, and a number of videos up on Youtube to guide you along. They aren't the only ones, but they sure are a great resource for asking questions.
Hope this helps. Good luck!