Strange surface after curing

[meshmaker]

These are one of my first batches of prints. The prints themselves came out great, however after curing they have a very light discoloration on some parts of the surface. These parts were cured under water for roughly 2hr in a nail bed. Is there such a thing as over curing? This is the B9 Emerald. I gave the parts a quick wash with IPA before rinsing in tap water before curing.

I cured another piece without using water and this discoloration did not happen. Which is an easy enough solution, I can quite using water. But I have noticed others using water as well and was wondering if anyone has come across this before.

Thanks for any help anyone can provide.

[Archerm]

I have never used water with a uv light and have never had issues. I don't see the need for water using a uv lamp.

[mongerdesigns]

Alcohol and then water is a bad combination. However that shouldn't affect the casting.

[meshmaker]

Not sure why I wanted to try it under water. I guess I was hoping for a quicker curing time. And I'm still trying to figure out what works for me.

That was my next question. If the castings will be affected. I'll give it a shot and see what happens.

So alcohol rinse and then just air dry before curing?

[rkundla]

Since elemental oxygen inhibits the curing of the resin (see the CLIP printer for this fact in practical application), the principle is that by curing the resin under water or other clear UV passing medium, you get a quicker surface cure than in air.

The white coating in my experience comes from an interaction of the alcohol, resin residue and water with exposure to UV light. As mentioned in a previous thread, it is cosmetic in nature and has not been seen to have a negative impact during casting.