I would like to try sizing some papers in gelatin, then use them for Kallitype printing. The general reason is I'd like to get a smoother surface, and also try glazing.

Is there a way I can mix the sensitizer into the gelatin sizing, then be able to clear the print sufficiently?

The other option I was thinking about is, do a typical gelatin sizing with a couple layers, then add the sensitizer on top and expose as normal.

Thanks for your help as always!

Sizing the paper will not give you a smpther surface unless you mean to coat the paper with a layer of gelatin.
If you want to provide some gloss, I suggest you try your hand at albumen. It should give you more what you are looking for.

Perhaps I mean more so a gelatin coating.

I had tried various papers, including fixed photo paper, with Kallitypes to get a smoother, glossy appearance; but kept having problems with Solarization. One person suggested that the sensitizer was sitting on surface; and therefore more prone to solarization. I suspect a gelatin hand-coated paper would have same problem. Maybe applying sensiitzer before gelatin drys - just a thought.

I had nothing but problems with gelatin-sized paper (Rising Stonehenge). Maybe you should find a really smooth paper instead? Some papers meant for silk screening are quite smooth and have a slight sheen to them. Expensive, mind you.

I noticed some papers from Canson & Strathmore have a very smooth Plate surface. Perhaps I'll give these a try.

Thanks for the input so far.