Bond resin to resin with resin?

I would like to do a mod to a prop cast in polyurethane resin, by adding a second part of the same type of resin.

I wonder, can I put polyurethane resin in-between the two parts to bond them together?
Will it be a strong bond, or does it have strange properties when cured vs. non-cured?

Thanks.

In my experience freshly poured resin won't stick to fully cured resin well (flat faces). if you drill holes in the cured parts for the liquid to flow into and act as 'keys' that would be better.

SAS

I just use Devcon plaster welder to attach resin to resin.