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Crazing of polycrylic over shellac primer11/22
1. Walnut lacquer stain sprayed on, light wipe.
I made two samples with one having the shellac primer tinted to another color. The first time I did not get this crazing. The first sample I may have let the shellac dry longer before distressing and applying the polycrylic, but not sure on that. Also, I put the sample in front of a shop fan to speed drying of the polycrylic after it tacked up, but did this on the first sample as well, just not sure how long I let it dry before doing that.
I thought this BIN primer could go on just about anything and be topcoated with anything. I use it a lot as a primer on opaque paint jobs, and was using here because it drys fast and sands well.
Any ideas as to why I'm getting this crazing??
Ideas? Maybe because you used 6 different kinds and brands of finish on it. Likely something wasn't fully dry before coating again. Just get some conversion varnish tinted and spray one product.
Thanks for replying, but I wouldn't even consider using conversion varnish unless I was building a kitchen or bath cabinets. Nitro lacquer is about as toxic as I'll go with finishes for the mostly built ins and furniture type cabinetry I build that wouldn't get the type of use that would necessarily warrant a conversion varnish or similar finish.
I wasn't having problems with the shellac on lacquer sanding sealer so I'll take your advice and try another sample and let the primer dry for several hours or so before sanding and topcoating with the polycrylic; or can someone recommend another water clear finish that would be compatible with the BIN primer?
I guess if I had to I would try and get some white nitro lacquer tinted to the color I need and topcoat with a CAB acrylic lacquer, though if I remember from a demo can I got a while back it was pretty nasty smelling stuff too.
Stick with the nitro. Or start with the polyacrylic. Don't mix so many finishes.
I agree something in there wasn't dry.
The shellac was not dry. I would suggest switching to all water based products and those issues will disappear. General Finishes has a range of products that all work together that can give you just the look you are trying to achieve.
Why use sanding sealer if you are going over it with primer? If you are hell bent on sanding sealer. Switch to shellac based Sealcoat.
How long are you waiting between the BIN and wb?
Thanks all for the additional responses. The reason I'm using a sealer over the stain, before primer, is to create a layer of protection to avoid rubbing into the stain and lightening it or rubbing to bare wood.
You can see in this picture that I also used a heat gun on the corners and in random spots to create some lifiting/bubbling of the primer that could be scraped off for effect. I believe the lacquer sanding sealer did not bubble up with the shellac and that ended being a benefit to protect the stain while I did the rub through.
Yes, SealCoat would have made more sense before the primer as they're both shellac products but is difficult to come by in my area; I'd have to order online to get gallons and drive an hour to a Rockler store just to get expensive quarts. A lot of the products mentioned are not available locally, and I've called around quite a bit over the years looking for a knowledgeable supplier. In my area, it's mostly stains, water and oil paints and clear lacquer and polyurethanes. Good luck trying to find a store that can tint a lacquer or conversion varnish or even carries them in white, and even if I were to have them order me some, they wouldn't have the colorant system to tint them.
I finished another sample after giving the primer more time to dry and it did not craze this time; the label clearly states that the addition of UTC colorants will cause the primer to take longer to dry; I should have heeded that warning.
On another note, this crazing/alligatoring effect might be desirable for this antiqued look in some instances, except that I don't know if I could reliably reproduce it, lol.
I cannot add anything to the process, but I do like the finished look even thought it may not be consistent.....it may appeal to your client.
I found this post investigating my own issues with lacquer tenting over shellac. Wondering if the BIN was old. My shellac I made was old but it was able to be sanded in minutes so I felt it was usable. Later on another project I noticed that I could still thumbprint shellac weeks after applied.
I wanted to post a follow up to this. I used this finishing process(except I let the shellac primer dry overnight before light sanding, distressing, and topcoating) on a built in that I stored for almost a month in my shop before installing and it was holding up fine and the acrylic/urethane topcoat seemed to be pretty durable. I actually ended up using Kelly Moore's Kel Thane II instead of the polycrylic.
Here's a pic to show the lightly distressed look I was trying to achieve.
Very nice Steven, glad it worked out so well.