Recomended Caulking

[duraleigh]

Hi, Scott,

I misled you a little on that post. I should've said "too bad they used acrylic caulk instead of polyurethane caulk" You must have a flexible seal at that point because the pool vertical wall and the coping move independently of each other...not much, but they move. If you try to grout it, it will crack before you know it and possibly fall out if your temps are extreme enough.

I suspect they used acrylic caulk on your expansion joints on the decking as well. Again my advice would be to switch to poly when you get the old cleaned out. The depth of the caulk should roughly equal the width of the gap you're filling. Masking tape on each side of the joint is mandatory.

I got that Vulkem stuff at a local (I don't think they're a chain) industrial supply house that specializes in masonry accessories. Drains, waterproofing, etc. It's called "General Materials" The Vulkem is made by a company called Tremco. I'm sure there are others just as good but this one works so well for me, I've never attempted anything else. I hope you are able to locate it but, if not, talk with some concrete pros in your area and ask them what they use to seal expansion joints.

Dave S.

[Sprint54]

Thanks Dave.. Going to Reno on Friday and have some concrete supply stores to call on. Appreciate your help.

Kind Regards,
Scott

[waterweasel]

You might want to look at Vulkem #116 instead. The same colors as the #911are available, but #116 is suitable for continual immersion. I work for a company that sells Tremco products for the concrete industry, and we sell tons of the stuff to the pool builders in my area (Oklahoma City). If you go to Tremco's website you can find a dealer in your area. Out of all the different polyurethane sealants we sell, #116 is the only one I would use in your situation. It is probably around $0.50 per tube more, but worth it. Great product.... (by the way this is not a sales pitch)

[Sprint54]

Hi Dave, couldn't find Vulkem 911 in Reno on Friday but did find an equivalent. "Sikaflex 1a" Polyurethane sealant". Has all the same properties and performance as Vulkem 911. Now for the million dollar question. Is there a trade secret for removing the old polyurethane sealant? Over the weekend I have tried using a sharp utility knife, a high speed burr, chemical softening agents, other tools that will not be named and bad language, nothing penetrates this old stuff. I have searched the Internet and found solutions that involve heating and scraping the caulk, cutting the two edges with a special diamond blade ten pulling the caulk out, and more chemicals that are suppose to soften the old caulk. What am I missing? Thanks.

Kind Regards,
Scott

[duraleigh]

Hi, Scott,

I simply do not have a good answer. I've only installed it...never removed it. I can imagine it is a real pain trying to get it out of there.

Scott you might try johnbridge.com. It's a forum much like this one but for ceramic tile. Lots of really knowledgeable guys on there and they may have a good answer. If so, I hope you'll post back and let me know, too.

[Sprint54]

Hi Dave, well after I posted my question regarding how to remove the old caulking, I went out at lunch time to my local hardware store to take a look at their inventory of hand tools thinking maybe I would see something that would help with the removal. I left there with a 1/4" wood chisel. Got home and spent about 10 minutes with the chisel and was able to remove about 2 feet of the old caulking. Initially I had troubles getting the chisel started into the old caulk. I took a 'sharp' utility knife and made a verical cut into the caulking. This allowed me to get the chisel under and into the old caulking. Once I got into it, it was just a matter of applying a slight tug on the old caulking with one hand while wiorking the chisel into the edges and under the caulking with the other. The stuff just started peeling off, but it did take considerable work and force in some spots. Tonight after about 2 hours I removed half of the old caulking. Only another 55 feet to go.....I will have to go back over the exposed joint with a wire brush and compressed air to remove the loose material and pieces of caulk that still remain, but the 1/4" wood chisel does the trick. Here's a tip, about every 5 feet I would stop and sharpen the chisel. It looses it's sharpness rather quickly against the concrete and tends to push the caulking out rather than cutting and lifting. Mayber I will post a picture to document my progress. This is step one of many before the pool is open for the season. Thanks again.

Kind Regards,
Scott

[duraleigh]

Hi, Scott,

That's cool!! I don't think I would ever have thought of that but you can bet I'll file it away for future reference.

Sounds like you're being really thorough on your pool renovation. Gives a lot of satisfaction to do good work on a difficult task, doesn't it?

Dave