I was installing some doors a few days ago, anyway some of my things were in the bed of my truck and it started raining. After getting everything out of the rain, I noticed this gel substance all over the composite shims. What is this stuff? Is it anything I should be concerned about? I’ve been using composite shims just because I figured they were better than wood shims.
I’d appreciate some of your thoughts.
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Replies
Wondering if it was something else that got on the shims? Just checked mine in a bucket with some water in it and there is nothing there.
Go check them again.
I just ran some water over two of them- one of the old ones from that day, and a new bundle I just picked up. Let the water droplets sit on them for a minute- in other words don't wipe them off. Look closely at the water on the shim- the drops become gel-like in 20-30 seconds.
These are "SHIM IT" Engineered Wood Composite Shim, by SmartWood. Bought at HD.
Shid.
I just bought some of those.
Guess it'll make a good throwaway puttyknife.
be a versatile yankee
r u a feckless dastard?
I wonder how it affects the integrity of the shim...
I'm going to soak one for a few hours and see if it turns to mush or loses any of its composition...
what are these shims made of anyway? something in it reacts with water to form these gel-drops
any chemists here?
I think that this is worth checking on. I have used them in areas that could get damp.. .wonder if they will turn to gel?
I just put them in some water. I'm going to leave them in there until morning.
I'll let you know what happens.
I don't think the entire shim will turn to gel, that would be very bizarre. I'm thinking it's just a certain part of the composite material that's doing this. Still even that doesn't seem desirable.
I use Shim-it shims sometimes and thought I was doing the right thing by using them in exterior applications or situations where I thought they might get wet like shimming up against masonry/concrete. Doesn't it say either "water proof" or OK for exterior use, or something along those lines on the packaging material? I just went out to my truck and found some buried down there (no packaging material though) and put some water on one. It just appears to bead up. No jell formed in the 5 or 10 minutes it took me to type this. I also put one in water to soak over night.
BTW - when I first saw them I thought they were plastic crap, but once I used them I really liked them because of their uniform shape but more-so because of how easily they snap off.
Some trim carps like to take a shim pack and chop it up in maybe 3" pieces - these may not work for this kind of shim use method.
Perhaps the gel is the release agent that's mixed into the plastic.
"Perhaps the gel is the release agent that's mixed into the plastic."
I bet you're right, IdahoDon.
I'm glad to hear your immersion test doesn't show these shims to weaken in water. Like you, I have been favoring these shims for potentially damp locations.I use them installing base cabinets over concrete slabs. I keep an air space below all the cabinets and isolate them from concrete with the plastic composite shims.Since the composite has a higher compressive strength, I use them when granite countertops are going in. I find them annoying for door hanging--they are both heavier and smoother and have a tendency to slip out of place. Cedar shims are still my choice for door hanging.
> I find them annoying for door hanging--they are both heavier and
> smoother and have a tendency to slip out of place.Maybe you should try spitting on them a bit, so the glue softens up and helps hold them.
I don't usually spit on my work...I prefer composite shims for horizontal surfaces and cedar for vertical.Looks like we work & live in the same corner of MN.
Mine look fine this morning.. .so what is up?
You weren't anywhere near the Black Lagoon, were you?
I don't know bud... The ones I soaked overnight seem the same as when I put them in there... I'm thinking that either you got a bad pack or maybe some type of solvent got spilled on them in the back of your truck... I see no problem.
Same thing here!
I just took them out of the water and they are fine, I could not tell they had been submerged for twelve hours.
That gelly stuff must not indicate a weakness in the shim. It's just water reacting with something on/in the shim itself.
Maybe it like someone said - release compound. The things are obviously made in a mold.
I just installed a front door with them and thought they worked great. After reading the posts on this I put one in the sink with water on it. Yep, it got slimy all right, so I now have it soaking. I did like them for their evenness of size and clean easy break off in the jamb. I had just bought some more packs of them, will probably not use them in exterior work.
Mine passed the overnight test, too.
Want to be sure everyone saw that.