How long before cold or room temperature water damages the surface of my steel bathtub?
12 hours? 24? 96?When I bought the house I thought bathtubs were invulnerable. My tub was incredibly uncomforable as a tub, couldn't lean back, so made cushion out of 4 inch thick foam rubber, and then it was just fine.
I left about 10 inches above the edge of the tub, minus a part I carved out for my head.
I also made a skirt about 10 inches below the top edge, by cutting away the two inches nearer the wall, and by cutting horisonally at the sides so it wrapped around inside the tub.
And everything was well. Until a few months later, I moved the foam and the surface of the tub was damaged at the bottom. The water would drain out at the end of every bath, except for part of the lowest inch or less. That never drained and that's the only place the damage was.
Now I have occasion to partly fill the tub and leave it that way for maybe 24 hours and I'm afraid I'll damage the tub, and since the whole bottom of the tub is under water now, I"m afraid I'll damage a lot more than part of an inch. I know an hour won't hurt it, but how long have I got until it's damaged?
Or was there something about being between the wet foam rubber and the tub that caused the damage?
P.S. All later cushions were above the top of the tub only and were just as comfortable. Alas, I wish I had figured that out in advance.
An electric knife works well on foam rubber. A regular knife does a bad job and a razor does a mediocre job.