Sealing cement

[addy1]

Flash mate is clear, water proof, seals flashing. Is it fish safe, don't know, but it works great. I have used it for our gutters and flashing. ingredients, hydrocarbon, thermoplastic rubber, hydrocarbon resins.

 

[WolfStock]

Hmmm - maybe. The thing with the Sika is - it's actually generally clear on most surfaces, even when exposed to water in rain and such. It only turns milky in the areas that have constant running water.

Here's a pic showing what I mean - the whole rock is actually covered with the stuff (and exposed to rain), but it's only milky on the parts where water constantly runs. I wonder if the same thing might happen to FlashMate.

 

[WolfStock]

After looking around and thinking some more, I'm going to try something different - silicone caulk. At least for the water "run" areas that are underwater, seems like it'd work OK to do a thin layer - in essence just a really thick layer of sealer. I figure if it doesn't work for some reason I can always peel/scrape it off. I'm hoping that'll also help in terms of cracking - i.e. any thermal or movement cracks that happen in the mortar will still be sealed by having the somewhat-flexible layer of caulk on top.

I'll hand-apply it with my finger. Since the runs are narrow (2-4 inches wide) it shouldn't be too tough. (I've done plenty of caulking before - just never for something like this)

Before I start - anyone want to talk me down from the ledge? I'll at least just start with a couple of smaller areas, and not do the whole thing until I see if it works.

I was hoping to do it this past weekend but didn't get to it. Will post results afterwards.

 

[addy1]

Did you look into the pl roofing sealant? It is black, you could make it look like cracks in the rock.

 

[lifeworthliving]

I bought my last one from Foster and Sons. The price of a EPDM was cheaper than Ebay and shipping was 8.99 for a 300 lb liner.

 

[WolfStock]

Problem is I really don't want to use black if I can avoid it - I want more of a natural look. EPDM seems great (e.g. Pond Pro 2000 looks just like what I'm looking for actually), except I only see it anywhere in black.

I'll see how the silicone caulk works - hopefully it'll work out; if not then I may resort to using the Pond Shield (epoxy) thing, which does come in clear though is pricey ($80/qt plus $16 shipping).

(P.S. life... I assume you meant "Foster and Smith" right?)

 

[DrDave]

Most urethane is a medium grey and blends in with most rocks. ten times better that RTV and perhaps more durable than epoxy.

 

[WolfStock]

Tried the silicone caulk thing the other day - so far so good actually. It held well, and looks pretty decent. Will have to see how it holds up over time though.

Pics in this other thread:

https://www.gardenpondforum.com/my-mini-pond-pics-and-stories-t5444p6.html

 

[WolfStock]

Well... caulking as a sealer FAIL. It turned milky white after a few days as well. On to the "nuclear option" of the Pond Shield (need to call them to get confirmation for sure that it won't turn milky, first).

In the upper bin and runway, the areas can be seen where the water was touching (white) vs. the areas not touching (dark grey - concrete), with quite a stark line dividing them. Also there's my rock runway where it's fairly milky where the water ran.

Oh well.

 

[WolfStock]

Or heck - I might even try the spar urethane that's worked well on the water wheel and trough. It's made for wood of course, but it's held in place and doesn't turn milky from extended water exposure.

 

[DrDave]

Use the urethane where you need to bond the liner and Thoroseal where you need to bond rocks or repair cracks in concrete. I used this combination 5 years ago and it is still holding today on my large waterfall.