Caulk question?

[Dan Forman]

I recently made a sawbuck to be kept outdoors, and used for breaking down green wood for turning blanks. I used both Titebond 3 and some strategically placed screws (in locations not likely to meet the chainsaw blade). I used treated 2 x 6's, and would like to caulk over the screws and some of the joints to seal out water as much as possible.

The tube of "DAP Acrylic Latex Caulk Plus Silicone" says "caulk in temperatures above 40 degrees F.", and "allow to dry two or more hours before painting. Caulk applies white and dries in 7-14 days"

My question is, how long after applying the caulk do I need to wait before bringing it outside and using it? I live in Eastern Washington and we get a lot of moisture this time of year (over 60" of snow this December), and variable temps, generally below freezing at night. Thanks

Dan

[Rich Engelhardt]

Hello,
Dap "Alex" will dry overnight and can be put outside after that.
The final cure will be suspended until the temperatures warm up.
It will defiantly affect the integrity of the material though.
Figure on half to a quarter of the listed expected life of the caulk.
IIRC, Alex is a 25 year material. Off the top of my head, based on having done similar in a pinch, I'd suspect about 5 years.

Pure silicone can be applied in temperatures down to 0*F. it will take weeks for it to dry though. Again, the integrity will suffer but not as much as the Alex.

If appearance isn't a concern, you can use roofing tar or PL500 adhesive.
Either/both of those (IIRC) go down to 10*F for application temperature.
Possibly lower for the tar.

The added plus for either of these - especially the PL500 - is that they can go on unweathered pressure treated material, where the Alex really can't.
IMHO - putting it over unweathered treated is going to affect the Alex more than the temperature.

Also - Re: the screws. Make sure you used the right ones for pressure treated.

[M Toupin]

Dan, what exactly are you trying to accomplish by caulking the screw heads? Think deck here... have you ever seen a deck with all the screws caulked? Use some through bolts that you can tighten periodically as it dries out to keep it tight. It's not fine furniture, a saw buck is an expendable item that you'll need to replace every 5 years or so anyway.

Mike

[Josiah Bartlett]

I think the caulk is a bad idea. It will actually trap moisture against the screws. If you have free air you get the chance for water to evaporate out. The wood is already wicking moisture in and out of there, so I wouldn't seal the heads. The heads are the last thing to fail on a screw anyway, the shank always fails first.

If you want to cover the heads to keep standing water from forming, use doweling or a wood plug.

[Dan Forman]

Rich---Thanks for your response. The PL500 looks like the way to go. I can apply it inside, just wondering how long it would take to cure before I can bring it outside? Is it readily available at one of the Borgs?

For screws, I just used the yellow zinc square drives from McFeely's. Looks like I should replace them or just add some stainless ones eh? Thanks for bringing that to my attention, I never would have known!

Dan

[Dan Forman]

Mike and Josiah---Well, I have no experience in such things, just thought that by caulking the heads and joints I could keep water from getting in to rust the screws, and slow down the aging process.

I didn't want to use bolts on the legs as it would put them too close to the blade action, whereas screws would be buried and farther away from the action.

Here is a pic, as you can see, no pretensions to "fine furniture " here. :)

http://i98.photobucket.com/albums/l279/T-Caster/P1020182.jpg

You can see that there is a little end grain facing up at the top of the legs, where they had protruded a bit and were trimmed. Not sure why I did it that way, but it's too late to change it now. That was one area I thought it might be a good idea to seal.

Dan

[Rich Engelhardt]

Hello Dan,
I just checked PL's site and you can apply PL500 down to 10*F, so you don't have to wait at all to take them outside. - unless it's below 10*F that is.

Personally, I'd gun it out on a piece of scrap, then use a putty knife to trowel it in.

The treated itself & even the screws don't need any protection from water to prevent rotting or rusting.

What it may prevent or slow down though is water getting into the seams and freezing.
The freezing would push the joints apart, which would allow more water in, which would push the joints apart,, which would,,etc.

& yes, one of the borg should have PL500. I've seen it next to the treated bunkers.

'course, if you already have some Titebond III, you can always brush some of that on too and let it dry instead of using caulk, PL500 or tar.

[Jason Roehl]

I think you'll find PL500 skins over too quick to be easily troweled in. You'll end up with a sticky, chunky mess.

From the description you read on the Dap Alex, it sounds like you have a tube of clear. Clear acrylic-latex caulk cures much more slowly for some reason. Go with the standard white in the Siliconized Acrylic Latex. Put it on, wait a couple hours before you put it in the weather and/or service, and don't worry about it.

It's not an heirloom, so don't over-think or over-engineer it.

[Loren Hedahl]

What I have done for similar project is to thin out some oil-based polyurethane about 10 percent and coat the whole item, giving a double portion to end grain and screw heads.

Then, before this dries completely, give it another coat or more with the poly un-thinned. After doing this, my screws seem to stay tightened better and I've never seen rust or dark spots develop around the heads.

Another little trick is to dip the threaded portion of your screws in poly (either paint or varnish) and drive them in wet. Of course, we're not talking fine furniture here, are we.

[Jason White]

Dan, try a product called DAP "Sidewinder." You'll find it at Home Depot.

Totally waterproof and very, very flexible. You can apply it down to 0-degrees, and it's fully paintable. Acrylic, latex caulks just don't seem to stay flexible enough outdoors.

Jason


I recently made a sawbuck to be kept outdoors, and used for breaking down green wood for turning blanks. I used both Titebond 3 and some strategically placed screws (in locations not likely to meet the chainsaw blade). I used treated 2 x 6's, and would like to caulk over the screws and some of the joints to seal out water as much as possible.

The tube of "DAP Acrylic Latex Caulk Plus Silicone" says "caulk in temperatures above 40 degrees F.", and "allow to dry two or more hours before painting. Caulk applies white and dries in 7-14 days"

My question is, how long after applying the caulk do I need to wait before bringing it outside and using it? I live in Eastern Washington and we get a lot of moisture this time of year (over 60" of snow this December), and variable temps, generally below freezing at night. Thanks

Dan

[Dan Forman]

Thanks for all of the responses. If the DAP Sidewinder works with treated lumber, I think that's the way I'll go. The freeze - thaw - pushing apart issue was one of the things I wanted to avoid with some sort of caulk.

Dan