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Jim Yanik

(Chris Lewis) wrote in
:

According to Jim Yanik :
"Edwin Pawlowski" wrote in
news:TqDAi.4376$Ay3.264@trndny02:

"Brian O" wrote in message
...
I have a plastic bathtub with a small crack in the bottom of the
tub. Short
of tearing it out and shoring it up, is there a way to at least
temporarily
repair the tub that will last a year or so? Thanks in advance.

If it is truly plastic, I don't have any idea, nor do I have much
hope of a long lasting repair. We'd need to know what type of
material it is.

If it is fiberglass, it is possible to lay-up some cloth, same as
you'd do with a boat. In any case, done from the tub side it will
look like crap, but if it buys you time and works, you can put up
with it for a time.

I suppose he could glass the entire tub bottom and blend/fill in the
edges with the curve up the sides.It would take several layers of
glass cloth,and need at least two weeks to cure before putting weight
on it. And rough up the tub surface for adhesion before beginning the
fiberglassing. He would also have to use a tub epoxy paint for the
top coat;add another week for that to cure.

I don't think you need to go that far - if you can't get at the bottom
of the tub:

- Scuff sand the affected area, swab with alcohol.
- Lay down 2-3 layers of fiberglass (top layer 2oz if available)
with an inch or two overlap on the crack.

that will leave a very obvious patch visible no matter how good you are.
I suggested doing the entire tub bottom so the seam would be at the tub
sides,blending in with the curve.Plus,with all that added bond area,it
would not pop off with the tub bottom flexing under a person's weight.

- Liberally brush on good epoxy (eg: West Systems)
- Lay over top some heat shrink window film, avoid bubbles, solidly
tape the perimeter, and gently heat gun it slightly to take out any
wrinkles.. Make sure the epoxy covers the scuffed areas.
- put a small sand bag on top. Or, if you sealed the window film
really well,
put in a couple inches of water.
- let sit for 24-48 hours, then, strip the window film and gently soap
wash the epoxy.

Epoxy doesn't stick to heat shrink window film, it's easy to get, and
makes the epoxy almost glass smooth. No sanding required.

Tub should be useable in 3-4 days. If it's takes longer, you can
coax it a little faster with a hair dryer (keep the epoxy _under_
150F).

Epoxy doesn't *fully* cure in 3-4 days.
Your patch would not gain full strength for a couple of weeks.Putting a
person's body weight on it would likely break the bond or it would crack at
the original crack.

If you can find a dye match (additive to the epoxy) for the tub, and
work the film/edges properly, you can make it practically invisible.
But I wouldn't trust it for that long. Putting a big sloppy epoxy
patch on the underside would be a better/easier, and you
could just run a small bead of epoxy on the inside of the tub
crack to avoid grud buildup.

--
Jim Yanik
jyanik
at
kua.net