Tinted Primer as the Color Coat
Instead of a tinted topcoat, is it practical to tint the primer coat (shellac or tinted CV primer), and then top with clear? July 14, 2010
Question
I previously tinted white conversion varnish with universal tinting colors to yield an off white color and created a stink bomb smell on the finished product which took months to wear off. For some time I have used white shellac primer tinted to my desired color. Then I just clear coat with a couple coats of the CV. Is there any downside? Does anyone else do this?
Forum Responses
(Finishing Forum)
From contributor C:
You should not use conversion coatings over reversible coatings. You might have success in the short term.
From contributor G:
Tinting a catalyzed primer and covering it with a catalyzed clear is done by a few other finishers I know. I’ve never seen any problems because of it. It’s quick and easy and gets the job done.
From contributor F:
I don’t know about going over the shellac primer but I will frequently have a post-cat primer tinted to my final color, then topcoat with CV (MLC Krystal over MLC Clawlock). The problem with doing this is if you ever need to spray another piece to match from a different batch of primer. Apparently the primers are not considered to have any tint strength, which simply means the base white can vary from batch to batch. That being said, I have not had a problem. I will typically do this on glazed jobs. Instead of having to use primer, pigmented lacquer, clear lacquer, glaze, then clear lacquer, you eliminate the need to buy the pigmented lacquer.
From the original questioner:
Thanks for helping me make my point. It seems a waste to prime, color coat, and then clear coat when you can eliminate the color coat step.
From contributor F:
Like I said, I’m not sure about going over the shellac based primer. I have heard of issues with CV going over shellac. I’ve never done it myself, and really can’t offer anything other than "I heard it’s not good". For a lot of my pigmented stuff, I will simply just prime and then use tinted lacquer - no clear. I only use a clear over the tinted if it is glazed/distressed/etc, or if the customer specifically requests it.
From contributor A:
I know several shops that do clears over tinted primer - usually the MLC Clawlock/Krystal combo. MLC happens to have the best distribution in our area. The CV/shellac combo is unusual. I'm surprised you aren't using a catalyzed primer like Clawlock. Colored topcoats are typically opaque clears so they do not have to be clearcoated. The major idea is burying the defects in the primer color coat under a couple coats of clear.
From the original questioner:
I believe in general that clear top coats are superior to pigmented top coats. Almost any finish is stronger and more impermeable when it is not weakened by a lot of pigment particles around which it has to coalesce.
From contributor L:
Aside from the white base in the primer not being consistent, the person who mixes your primer needs to know that it is not being color-coated. When matching or remaking a topcoat color, there are checks done against a retain of the previously made color. When tinting primer, the standard is to pump in 3/4 of the topcoat color Rx, shake it and send it. No color checks performed.
