Scuffing Vinyl Sealcoat Before Glazing
Fine points of the scuffing step in a glaze finish process. July 27, 2008
Question
Does anyone have a good recommendation regarding the scuffing before glazing? I have used 220, 320, and purple Scotchbrite, but still, the scratches in the vinyl sealer base coat are heavier than I would like. I've thought of using #1 steel wool and will try that, but could anyone recommend another method of scuffing before glazing?
Forum Responses
(Finishing Forum)
From contributor A:
You may try 400 grit or a superfine 3m sanding sponge. It will also help if you allow the sealer to dry a bit longer, possibly overnight.
From contributor B:
Are you catalyzing your vinyl sealer? Also what kind of effect are you looking to achieve? There are as many types of glaze finishes as there are finishers.
From contributor C:
How long are you allowing the vinyl to dry? Is it a single component sealer? Are you laying down too heavy a coat?
From the original questioner:
I'm using ML Campbell waterwhite vinyl sealer, uncatalyzed, spraying two passes from a Kremlin gun-pump system. The vinyl sealer is drying overnight. I'm looking for very light glaze over white, a little heavy in the corners. Probably catalyzing it 1% would make it harder and less coating one pass would make a shallower scratch. I considered 400 grit paper, and the ML Campbell tech thought it might be too fine. I have glazed directly into scuff conversion varnish before, but ML Campbell recommends the vinyl sealer sandwich. Thanks for you comments! Let me know if anything else comes to mind. I'll try a few of your suggestions.
From contributor B:
If the vinyl sealer isn't catalyzed I will spray on a thinned coat of sealer, scuff sand and then spray on a smooth coat of sealer. Now you can apply your glaze without scuffing as long as it isn't a real heavy glaze coat and then spray on another coat of vinyl sealer. This way you won't have a problem with scratches and the vinyl will melt together just like lacquer would so your topcoat won't lift or have any adhesion problems. Give it a try on some samples and see what you think.
From contributor D:
Easy solution, I never scuff before glazing. I use Valspar glaze over their vinyl base coat (a colored primer) and let it dry about 4-8 hours depending on how much glaze is left on the surface. No vinyl sealer, no recoat windows, no adhesion problems.
From contributor E:
If you use the MLC Amazing Glaze, you can "scuff" it with a mineral spirits damp rag.
From contributor F:
There are a lot of different techniques posted here and it seems that everyone goes through a learning curve to find what works for them. Been there and done that. I use MLC traditional glaze thinned 3 parts glaze to 2 parts mineral spirits to avoid the vinyl sealer. I spray MagnaMax tinted base (usually white), sand with 320, scuff with purple scotchbrite, then spray or wipe on the glaze, then remove what I don't want with a rag. You can use naphtha or mineral spirits to dampen the rag to pull off more glaze or pull it out of scratches.
From contributor G:
We use MLC clawlock for the color, then a coat of CV200, scotchbrite, glaze (1 part to two mineral spirits), then topcoat with the CV200. It comes out very nice.
From contributor B:
To contributor G: Are you using the amazing glaze? If not, it seems like a mineral spirits glaze sandwiched between coats of CV could potentially cause adhesion problems.
From contributor G:
It's Campbell's conventional glaze and we leave material in corners, molding lines, etc. only. We've used this process for 3-4 years with Crystal before the CV200.
