I'm continually disappointed with the quality of fasteners bought from Amazon. What you get from McMaster is much better. The problem, I guess is that Amazon is too low quality and McMaster is too high quality.
I also don't think they mark everything up 100%. I have built a lot of stuff out of T-slot extrusion ("80/20") and their price seems exactly the same as buying from 80/20 directly. I guess there is probably some Aliexpress vendor cheaper than the brand name, though.
I also don't think they mark everything up 100%. I have built a lot of stuff out of T-slot extrusion ("80/20") and their price seems exactly the same as buying from 80/20 directly. I guess there is probably some Aliexpress vendor cheaper than the brand name, though.