Filler

I’m ready to start the clear on my guitar. I went over the top with Stew Macs Lawrence-McFadden Grain Filler. The last guitar I built I also used it with good results for the most part. The one problem I had on the head a cloudy spot (about 1in. diameter) appeared after a couple weeks. I have never had this happen before. I used lacquer for the finish, the filler is oil base but they say it’s compatible with lacquer. But I’m thinking ,maybe I had to much build up of filler wear the cloudy area is it might leached into the lacquer. So I’m thinking about putting coat or two of shellac on first before I start the lacquer. So any ideas of what the spot could be? I would rule out blushing I’ve had lacquer blush but always right away plus it was ideal weather. Another question do you think pr-mixed shellac would be alright to use?

I had an alder body blush to large areas of milky white a while ago it happened after 4 hours of drying. blush can appear after several days. I fixed it by lightly spraying it with a can of "no blush plus" per recomendation of friend and it completly went away. could also be from the filler or even silicone contamination. I always use a couple drops of silacheck just in case, stops the fish eyes too

I might try the no blush Looking at it with a magnifier I’m thinking filler build up is the problem. Spot is by the truss rod cover so it’s not that noticeable except to me. I’ll try the no blush first. Thanks