clear coat for latex?

[blackhawk]

I've have been working on a sign that is mainly painted with latex. It does have some parts that are done with One Shot paint, which is oil based. The specifications on the sign call for it to be clear coated in a matte finish. The latex paint is all Sherwin Williams and my local paint store called their technical expert and he suggested Sher-clear. http://protective.sherwin-williams.com/detail.jsp?A=sku-26019%3Aproduct-6794 They said that it would work fine over the One Shot also.

I made a sample board and painted the clear on there for a test. It is milky from the can and it dried semi-clear. In my opinion it looks awful. I am going to make a test spraying it, but I am really worried about it.

Has anyone got a suggestion for a flat clear coat that would work?

I really don't see the need for the clear coat and especially not a flat one. But I cannot talk the customer out of the idea.

[feinddj]

Provide samples and have the customer sign off on it. CYA, especially when you don't think that it helps and even detracts from the work. The end is that the customer is paying for certain things and your job is to do that for him. If they don't like the final product, show him the samples and his sign off. If that loses you a client, you might consider that you might not need them as a client if they ignore your advice.

[pappybaynes]

I've have been working on a sign that is mainly painted with latex. It does have some parts that are done with One Shot paint, which is oil based. The specifications on the sign call for it to be clear coated in a matte finish. The latex paint is all Sherwin Williams and my local paint store called their technical expert and he suggested Sher-clear. http://protective.sherwin-williams.com/detail.jsp?A=sku-26019%3Aproduct-6794 They said that it would work fine over the One Shot also.

I made a sample board and painted the clear on there for a test. It is milky from the can and it dried semi-clear. In my opinion it looks awful. I am going to make a test spraying it, but I am really worried about it.

Has anyone got a suggestion for a flat clear coat that would work?

I really don't see the need for the clear coat and especially not a flat one. But I cannot talk the customer out of the idea.

I use Rustoleum's Painters Touch Ultra Cover...used the matte and gloss over latex and one shot...get it at Home Depot. Apply several thin coats...I allow about an hour between coats and after I have 3 coats or so I leave it for 24 hours...sometimes I will do a light sand with 600 and apply one more coat...

[jTr]

Interior or exterior?

If interior:

I've had very good luck using Sherwin- Williams T77-F62 (or 63) "conversion coating" over latex paint. On occasion, I need to paint a base color, glaze to enhance distress marks and profile details, and sometimes rub through to expose a dye- stained layer depending on desired effect. All of this needs to be sealed before put into service. This is a C.A.B. acrylic, which does not shift the tone of the underlying colors nor will it yellow over time - critical for this type of situation. Though it is an acrylic, I usually cringe when putting on the first coat, as it is a solvent based product going over a waterborne paint, but I've experienced no disasters yet.

Here are some important rules I follow:
- Use flat latex paint - typically cheap, low tech (low budget)varieties
Tried a sample of satin black with clear topcoat and it had an odd look - you could see the satin paint sheen reflecting through the clear coat, whereas a flat simply blends in and looks much more natural. (see sample picture below)
- Allow minimum 24 hours dry time, more if high humidity.
- Always create a test sample

I've got samples on hand from each of those projects that are several years old and remain very durable. Have even done this for several bath cabinets with no failure.*

*I'm qualifying because the paint store employees would not likely sanction this mix of products - Its worth repeating: always test for compatibility on scraps to verify before attempting on any project.;)

[blackhawk]

Jeff - This is for an outdoor sign. I couldn't find in links for that particular product that you mentioned. Do you have a link that has a datasheet?

[pappybaynes]

Jeff - This is for an outdoor sign. I couldn't find in links for that particular product that you mentioned. Do you have a link that has a datasheet?

The product I mentioned is interior or exterior

[jTr]

Sorry, Brad - page two of spec sheet I have on hand says specifically:
"-For interior use only"

Don't have link, but code on my data sheet says "CC-F52", which I believe is the document number for the T77 series. If you're having trouble finding, they omit the dash in the data sheet. Try T77F62 as you search if you still want to read up on this product.

Jeff

[blackhawk]

Dick - I ended up using the Rustoleum Ultra Cover that you suggested. It worked out fine. I took the Sherwin Williams and got my money back on that.