Becoming Disillusioned With the Utility of Resin Printed Components

[cliffyk]

I have downloaded and scoured everyone of Siraya's data sheets and those available for most other resins (I'm a mechanical engineer so reading spec sheets of materials I might use is 2nd nature). What I've found is that any resin with an elongation at break of < 20% is not suitable for any loaded component. A block of ice would work just as well and likely have a little bit longer service life...

So, would Siraya Blu be suitable? Elongation at break is 25%.

I have not yet used it; I'm having a hard time coughing up the $$, in part because i do not like the colour (blue or clear).

I do have some Siraya Tenacious (claimed 50% EAB) on order (not wild about its colour either but I paint over 1/2 of what I print anyway).

I used a kg of SainSmart Rapid General Purpose resin rated at 28% to 35% and it was OK ("OK" in my vocabulary means "barely adequate).

A stated above, the best I have used so far was the Phrozen Functional Resin: Beige Flex that apparently has been discontinued. It was $40/kg with 50% to 60% elongation at break--based on that experience and my using resins rated 14% to 20%, i think 25% would be just barely adequate ("OK-").

In my experience--just coming up on 1-year, 3.5 LCD screens (my 4th is about 1/2 way through its service life), and 50 to 60 kg of resin--anyone's "water washable" stuff and most (probably ALL) resins touted as "ABS-like" are so brittle as to be useless for making anything but the most lightly loaded components--and then only if you up-size said component to be 10% to 15% larger than if you were machining it from a block of reinforced phenolic resin (itself not an especially robust material). I.e. pretty much useless.

I hope to mix the Tenacious with some of the "ABS-like" garbage I've amassed and come up with something useful... 

I will report back when I've used it a bit...