Can cured photoresin parts be reliably joined like (ABS + acetone)?

General Discussion
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I’m thinking of getting a SLA printer, but the big uncertainty holding me back is whether I can build large things like propellers by printing them piecewise and fusing them together like you can with ABS and acetone (or butanone).

The resins are proprietary, so I guess that’s why I can hardly find any information on this. Here’s what I know:

  1. According to Wikipedia, photopolymers are thermoset, so that rules out melting them.

  2. Vapour polishing anyone? - “they became very brittle, almost crumbly”
    https://formlabs.com/support/finishing/solvent-compatibility/

So acetone weakened and chemically changed the plastic.

  1. JoshK claims the resin is cross-linked acrylic. Acrylic is dissolved by Dichloromethane, which can be found in paint thinners.

Any hope of dissolving the curred resins in a solvent? If not, what about joining using joints (e.g. dovetailing) and super glue. Will this get 95% of the original yield strength like you can with ABS & acetone?

2

Superglue works well. Alternatively, you can use the uncured resin plus a 405nm laser pointer to get the same strength as the curing process in the printer.

This blog post goes over some techniques for large prints.

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I’ve used 5 minute epoxy to great effect. I even tried breaking the joint after a few days, and succeeded in shattering the piece but not at the joint.

So if you need a strong bond, use epoxy.