Soft Spot In Tub Floor

[Deb Mac]

Well it didn't work. The stuff still in the bag didn't set. It all disintegrated back into liquid form. There was a nice big ball of cured foam outside of the bag. It had continued to expand slowly, but nothing supporting the floor. I suppose it is possible that with the "blob" sealing the edge of the ziplock, there was nowhere for the foam in the bag to expand to, and then just retracted. I will do an experiment with the remaining stuff in the can and see if it can work and what the optimal volume into a ziplock bag might be

So I carefully detached and pulled out "The Blob" (turns out it didn't adhere too robustly to the floor), attached to the ziplock, and went back to the styrofoam block approach. Managed to cut a wedge of the correct size that would both fit through the gap in the wiring that I was working through, and slide in behind the vent pipe and still be large enough to support the corner. It needed to actually support the back wall and flat floor of the tub at that spot.

Floor is now nice and solid. I imagine with time and motion it may shift, but at least I know how to get at it now and exactly where I need to work. If at some point I can get the converter to shift out of the way so I'm not working through an arm sized gap between the converter and the wall, I might be able to do a more permanent fix. But until that time, I will get by fine with what's there now.

[Wavery]

I think that you would have to leave the bag open. It needs air to expand and cure. This stuff needs moisture and oxygen to expand. Normally the moisture in the air is enough but in this case, wetting the inside of the bag may be necessary.

[Deb Mac]

You’re probably right about the air. I’ll take what’s left in the can and see what the expansion volume turns out to be in an open bag. Maybe next time tuck a long bag under that corner with a much smaller volume of foam injected.

[FlyboyTR]

Originally Posted by Deb Mac

Well it didn't work. The stuff still in the bag didn't set. It all disintegrated back into liquid form. There was a nice big ball of cured foam outside of the bag. It had continued to expand slowly, but nothing supporting the floor. I suppose it is possible that with the "blob" sealing the edge of the ziplock, there was nowhere for the foam in the bag to expand to, and then just retracted. I will do an experiment with the remaining stuff in the can and see if it can work and what the optimal volume into a ziplock bag might be

So I carefully detached and pulled out "The Blob" (turns out it didn't adhere too robustly to the floor), attached to the ziplock, and went back to the styrofoam block approach. Managed to cut a wedge of the correct size that would both fit through the gap in the wiring that I was working through, and slide in behind the vent pipe and still be large enough to support the corner. It needed to actually support the back wall and flat floor of the tub at that spot.

Floor is now nice and solid. I imagine with time and motion it may shift, but at least I know how to get at it now and exactly where I need to work. If at some point I can get the converter to shift out of the way so I'm not working through an arm sized gap between the converter and the wall, I might be able to do a more permanent fix. But until that time, I will get by fine with what's there now.

Deb,
I am so sorry that it didn't work out for you. The day I did ours we were in our typical 95% humidity and I used a bag that I didn't try to close/seal...so it was open. I guess air was able to make it's way through the bag. Maybe that is why mine worked without issue. Could be that a larger bag is the answer. Glad you were able to get some support under the tub.

[Deb Mac]

Do you recall what brand of foam you used? There may be some differences in chemistry that allowed yours to work in that somewhat enclosed setting.
Plus it is dry as a bone up here. Likely a very poor combination of conditions for foam in a bag.

[FlyboyTR]

Originally Posted by Deb Mac

Do you recall what brand of foam you used? There may be some differences in chemistry that allowed yours to work in that somewhat enclosed setting.
Plus it is dry as a bone up here. Likely a very poor combination of conditions for foam in a bag.

Don't remember exactly which foam I used. It came from Home Depot. I would say try it with a large (kitchen/bathroom) type. So...you're not trying to fill the bag, but applying the foam where you need it but just inside the bag. If things are really dry, I would say to wet the bag first. The larger bag will allow air space around the foam. So maybe with the water and the air space, it may make a difference.

[Deb Mac]

Originally Posted by FlyboyTR

Don't remember exactly which foam I used. It came from Home Depot. I would say try it with a large (kitchen/bathroom) type. So...you're not trying to fill the bag, but applying the foam where you need it but just inside the bag. If things are really dry, I would say to wet the bag first. The larger bag will allow air space around the foam. So maybe with the water and the air space, it may make a difference.

I'll give that try when I need to get at it again. Or if I get a chance before the cooler weather hits us. Labour day coming... up here we could see snow any time after that! But I don't think that's likely this year!