"Glue sizing" for me is a result of hammer veneering with (hot) hide glue both as adhesive and lubricant; however, varnish seems not to be very compatible with it probably since it penetrates so much - shellac might work better. I bet that if you wet-sanded with hot water, the glue-size would fill the pores right up (but I'm a scraper kind of guy). Neat-o. Clark
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