BS: Watching the paint dry - it didn't

Subject: BS: Watching the paint dry - it didn't
From: ragdall
Date: 06 Aug 10 - 10:30 PM

I'm making something wooden for children to climb on/dangle under. I painted it yesterday with an oil based paint. The instructions said to let it dry overnight. It's been more than 24 hours now. Most of it is dry but a few places where I must have brushed it on a little thicker are still tacky. I want to put the next coat on, but am afraid if I put more on it will never dry.

Does anyone have experience with this? Is it okay to paint over tacky paint? Is there a way to make the tacky part dry? I'm tempted to wipe it gently with a cloth wet with paint thinner (mineral spirits) to remove the thicker part.

Thanks,
rags

Subject: RE: BS: Watching the paint dry - it didn't
From: Little Hawk
Date: 06 Aug 10 - 10:55 PM

No, don't wipe it. You'll damage the finish and make a mess. You could try putting a heat lamp on the tacky parts or putting it out in the sun for a day. (assuming the right weather) Or just wait....

Subject: RE: BS: Watching the paint dry - it didn't
From: Little Hawk
Date: 06 Aug 10 - 11:03 PM

A hair dryer on "hot" would also help...the trouble is you've got to sit there holding it. That could take awhile. Paint will always dry faster in hot dry air than it will in cool or damp air.

If you just convince yourself you don't need it in 24 hours and give it enough time to dry completely, the problem will solve itself. Is that an option?

Subject: RE: BS: Watching the paint dry - it didn't
From: GUEST
Date: 06 Aug 10 - 11:44 PM

Is your air unusually dank right now?

Subject: RE: BS: Watching the paint dry - it didn't
From: ragdall
Date: 07 Aug 10 - 12:33 AM

Little Hawk and Guest,
Thanks for the replies. I can't put it out in the sun. I'm not sure what "dank" is. Thunder showers have been passing through and it's been raining hard. It's not cold, though (20-25ºC). I'll give it another 24 hours, if it is still tacky tomorrow, I'll try the hair dryer. I'm just worried that it will never dry and I'll have to junk the entire project and start again, or give up.

rags

Subject: RE: BS: Watching the paint dry - it didn't
From: Little Hawk
Date: 07 Aug 10 - 03:05 AM

"dank" means humid. Humid air considerably slows down the evaporation of the oils in the paint, so rainy weather will retard the process some. It will definitely dry after awhile, a few days at the most. The dryer the air around it is and the more circulated dry air (and heat) it gets, the faster it will dry. In other words, it would dry more slowly inside a shut closet than it would sitting out in a large open space where the air circulates better.

Don't mess around with trying to remove the tacky paint. Just wait for it to dry.

Subject: RE: BS: Watching the paint dry - it didn't
From: ragdall
Date: 07 Aug 10 - 05:31 AM

Thanks Little Hawk. I hope you're right. I'll hope for the weather to change.

Years ago I made a big rabbit from papier mache. I painted it, then coated it with shellac. It stayed tacky (sticky) for years. Finally I threw it into the trash. I'll bet it's still tacky, wherever it is. I was worried that the same thing will happen again.

rags

Subject: RE: BS: Watching the paint dry - it didn't
From: GUEST,Mrbenggo
Date: 07 Aug 10 - 10:25 AM

On one of the Scottish Orkney islands,every July they have a paint watching competition.Each contestent has a one square yard of flat board to paint and has to stay awake until it dries,some years ago an unknown person substituted the paint for anti vandel paint,none drying,and the competition was abandoned after four days.

Subject: RE: BS: Watching the paint dry - it didn't
From: frogprince
Date: 07 Aug 10 - 11:29 AM

When I moved from Chicago to our one-or-two horse town 28 years ago, the old courthouse downtown had a gold painted dome. A few years later they put gold tone metal plating on it. Life here is really boring now. We miss the excitement of watching gold paint flake off the dome.

Subject: RE: BS: Watching the paint dry - it didn't
From: Little Hawk
Date: 07 Aug 10 - 12:37 PM

You should check out the Crazy Horse monument webcam if you want REAL excitement.

Subject: RE: BS: Watching the paint dry - it didn't
From: Q (Frank Staplin)
Date: 07 Aug 10 - 02:23 PM

Most of us here in the colder areas have small electric heaters with fans that are used when extra heat is needed somewhere.

A simple electric fan also will help with drying.

Subject: RE: BS: Watching the paint dry - it didn't
From: MarkS
Date: 07 Aug 10 - 05:10 PM

But don't put your second coat on over the tacky part. I have found that the tacky spot will then enlarge, and when the paint finally does dry you might well have a visible flaw in the finish there.

Subject: RE: BS: Watching the paint dry - it didn't
From: Little Hawk
Date: 07 Aug 10 - 08:39 PM

Mr Bean has a video episode where he paints an entire room white with the aid of a small amount of explosive placed directly in the open (and full) paint can. First, however, he masks off everything in the room except those parts he wants painted white. He does this to save himself work! ;-) It almost works out okay in the end.

Subject: RE: BS: Watching the paint dry - it didn't
From: Smokey.
Date: 07 Aug 10 - 09:30 PM

Sandpaper the first coat smooth before applying the second coat, it'll look a lot better and last longer.

Subject: RE: BS: Watching the paint dry - it didn't
From: JohnInKansas
Date: 08 Aug 10 - 04:15 AM

The next time you open a can of paint, or a little before, might be a good time to put on a pair of specs and RTFM.

It may not be the practice where you are, but it's been decades since I've seen a paint can that didn't include specific instructions on drying time and conditions, and fairly specific instructions on what to do if you want another coat.

Oil based paints are subject to quite a bit of variation, and some recommend that the first coat be "fully dry" before applying a second. The majority, however - and most water based paints I've seen recently - suggest that the second (and subsequent coats) should be applied after the prior coat is "tack free and firm" but before the surface is "fully cured."

Some paints, especially those that tout "washable" as a feature, form a surface film that's relatively impervious to vapors and once that film is formed additional drying of paint beneath can be prolonged. Another coat that forms a similar barrier could make curing of the entire (multiple layer) paint thickness take longer than you'd want.

For most paints, the excess of solvents in the new layer will soften the prior surface sufficently that the combined layers will "dry" just like one thick one, with the benefit that the first coat is sufficiently "stiffened" while the "runny part" in the second coat is still fluid enough to "close" the brush strokes and thin enough to "not sag."

If the can didn't include label instructions for second coats, or some sloppy painter who used it before you did allowed the slosh to obliterate them, the paint shop where you got the stuff probably has something similar that is labelled.

If you can't find advice, the most common cause of slow drying (especially with oils) is high humidity. A hair dryer blown directly on the tacky parts might harden them fairly quickly - at least enough that you could feel confident about a second coat. If the sticky spots are mostly where there are "sags" cutting the sags off with a sharp knife is sometimes effective, and the next coat will cover the "correction." Sanding or scraping usually just makes a mess of it all, unless its done after the paint is fully dry; and any use of solvents is likely to make the whole thing "unpaintable."

In the abssence of any corrective action, a "thing for kids" can incorporate "magic spots" that turn the kid a strange color when the kid finds them, and you just tell the kids it's "a prize for outstanding performance." (And then you avoid the mothers until it's forgotten.)

John

Subject: RE: BS: Watching the paint dry - it didn't
From: Doug Chadwick
Date: 08 Aug 10 - 04:31 AM

RTFM    ?

Translation please.

Subject: RE: BS: Watching the paint dry - it didn't
From: The Fooles Troupe
Date: 08 Aug 10 - 04:44 AM

Read The F****** Manual....

Subject: RE: BS: Watching the paint dry - it didn't
From: ragdall
Date: 08 Aug 10 - 07:16 AM

JohnInKansas,
Thank you for typing the detailed instructions. I did read the label before obliterating it with paint. It said to allow the paint to dry overnight. It didn't. Well, some did, some didn't, but it all seems to be dry now, at least any of the parts that I touched on the top surface are dry. I'm hoping to do a better job with the next coat.

I found the unopened paint can in a cupboard in the basement. According to the price tag, it was purchased from a department store (not a paint store) which went out of business about 25 years ago.
I think for the next coat I'll need to buy a new can of paint. This project is getting to be much more costly than I expected.

Smokey,
Thank you for the advice about sanding between coats. I'll do that.   The former tacky parts are now fuzzier where dust (or maybe ash? -- we had a forest fire in town during the extended drying time) attached itself.   

rags

Subject: RE: BS: Watching the paint dry - it didn't
From: The Fooles Troupe
Date: 08 Aug 10 - 08:16 AM

"According to the price tag, it was purchased from a department store (not a paint store) which went out of business about 25 years ago. "

Ah - paint sitting around that long is likely to be 'off' - and will need extensive mixing - or it may not be consistent - and develop such patches as you describe.

Subject: RE: BS: Watching the paint dry - it didn't
From: JohnInKansas
Date: 08 Aug 10 - 10:46 PM

The bigger concern than the need for extensive mixing of paint "more than 25 years old" is that the time puts it closer to when lead (and/or cadmium) was commonly used in virtually all paint products.

A lead-bearing paint should be considered unsuitable for use, especially on anything exposed to children.

Bans on lead in paints in most places probably were well prior to that time (1980s?) but some places continued selling such things for quite a while after they were technically prohibited, espeially in oil based mixes.

If sufficient parts of the label are still visible, you might be able to check for a "contents" list(?) just to be reassured.

John

Subject: RE: BS: Watching the paint dry - it didn't
From: Alice
Date: 08 Aug 10 - 10:49 PM

If it is 25 years old or older, I would be concerned about lead, as John said. - A.

Subject: RE: BS: Watching the paint dry - it didn't
From: ragdall
Date: 08 Aug 10 - 11:38 PM

Thanks for raising the concerns about lead.

I'm fairly sure that several of these cans were bought for use on children's metal toys and wooden play equipment. The cans that remain must not have been needed to complete the projects. I would have checked about them being safe for that purpose when I bought them. Hopefully the children won't be climbing these ladders with their teeth in any case.

rags

Subject: RE: BS: Watching the paint dry - it didn't
From: GUEST,CAP
Date: 09 Aug 10 - 04:21 AM

Just seen this thread & thought it was about the English-Pakistan cricket match!

Subject: RE: BS: Watching the paint dry - it didn't
From: JohnInKansas
Date: 09 Aug 10 - 05:09 AM

rags -

If your paint was originally from the 80s, it's unlikely that it was produced before the main lead restricitions were in place, at least in "civilized" places, so I suspect that no real reason for concern exists. With the shelf life of merchandise in stores, and the permissions to sell "stock on hand" some places had it for sale for quite a long time after the bans were being officially enforced, but 80s (or even late 70s) would only be seriously suspect in backward/remote areas in the US.

HUD requires inspections for lead paint in the US only for houses built pre-1950 or so^*, and although my observation was that lead paint was still available some time after that most sellers would have phased it out by ca. 1980. VA requirements are similar to HUD.

^* I'd have to look through my mortgage papers to get an exact date, but our 1955 construction was waived through without inspection. I do know of farmers using leaded paint on implements as late as at least the early 60s, but their paint may have been from a prior archaeological age by the time they used it.

John

Subject: RE: BS: Watching the paint dry - it didn't
From: ragdall
Date: 10 Aug 10 - 02:10 AM

JohnInKansas,
Thanks for the reassurance about the lead.

I went out today to several stores that sell paint and asked about the safety of the paints that looked to be suitable for my purpose. I was told that, by government decree, oil based paints will soon be a thing of the past and that any oil based paint in a spray can will contain solvents which may be harmful to widdle kiddies. I bought a litre can of a gloss latex paint that the seller swore up and down has nothing harmful to children in it and will stand up to hard use and weather.

I will sand and try to paint over the old paint which is thoroughly dry now. It's cloudy, cool and was drizzling briefly a couple of hours ago, but it's supposed to be sunny and 25ºC tomorrow, (that's more than 70ºF, which is 20ºC), I'll paint it then.

The children in question will be here on Friday. I'm hoping by then the overhead ladder will be evenly covered in the guaranteed-not-to-harm children paint and will be thoroughly dry so they will be able to use it and I will be able to focus attention on how long (wide) bracing must be to to keep it from tipping over sideways when the ladder is used improperly.

Thanks, everyone who tried to help.
rags

Subject: RE: BS: Watching the paint dry - it didn't
From: The Fooles Troupe
Date: 10 Aug 10 - 03:03 AM

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