[Katherine Swift]

This question comes through email by Lucy:

Im using  Special water clear casting resin (arts etc) and catalyst to make my resin and so far have had a few problems I thought you might be able to help me with? This resin isnt like any Ive used before, it has a vile smell, but Ive been assured its for jewellery and Im using one of the right resins.

Firstly, as the resin cures it comes away from the mould like it shrinks slightly, and then on the front it leaves marks where the resin isnt completely cured..can this be sanded on the front of the piece?

Secondly, Its very sticky even after 3 or 4 days days, and then theres fingerprints on the front, do I need to leave it even longer? Is it possible it could take longer then a couple of days, or would the Novus remove this?

Thanks a lot

[Katherine Swift]

Hi Lucy,

What kind of resin are you using?  Since you said it has a vile smell, Im guessing its a polyester resin.  Assuming thats the case, its normal for polyester to cure with a tacky surface.  You will need to sand it off with a coarse grit sandpaper to remove the sticky part.  After the sticky surface is gone, use subsequent finer grits of sandpaper to get it smooth and glossy again.

[T]

That is an intended property of casting resin. Its purpose is to adhere to any addition layers.

There are several things that can be done. One is to add the surfacing wax. This eliminates the exposure to oxygen which causes the tacky surface.

Another is to sand and polish the surface after 24 hours.

You can also seal with a clear coating, i.e. Krylon.

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