Repairing a crack in plastic bathtub

[JoeSpareBedroom]

Is it really plastic, or is it fiberglass? If the latter, you might post this question in rec.boats.

[Brian O]

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. Brian

[dadiOH]

It is probably acrylic. If the crack is *small* and isn't spread out side to side so there is a gap you might try letting some super glue wick into it. No guarantee it will work. Takes a while to dry too...don't stress it for 24 hours.

Here are some acrylic adhesives...

[Edwin Pawlowski]

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.

[Jim Yanik]

"Edwin Pawlowski" wrote in news:TqDAi.4376$Ay3.264@trndny02:

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.

[Chris Lewis]

According to Jim Yanik :

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.

- 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).

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]

[e-mail] (Chris Lewis) wrote in news: [e-mail]:

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.

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.

[flir67]

I had a cracked fiberglass shower stall flooring, go to homedepot or lowes and look for a fiberglass repair its in the plumbing pvc section cost about 9.00 mine was almond colored and the mix was white, really smells so make sure you have ventlation when using it.let dry 1 week. yes 1 week.

then read up on painting or staining fiberglass tubs.. there's alot of info out on it.make sure its smooth and working before you paint!!

[george]

If the split in a patched shower pan suddenly lets go, it may not be much of a problem. If a patched split in a bathtub full of water lets go wide open, you may suddenly have several thousands of dollars of damage to your abode.

[Norminn]

clipped

Makes my butt hurt to think about the crack in the tub opening up. Ouch!

[Saucer Man]

Look in the yellow pages under Tubs and Baths and possible Water. There are outfits that can repair this if the crack isn't too bad.

[Chris Lewis]

According to Jim Yanik :

With West and the aforementioned shrinkwrap, being "obvious" is almost entirely a matter of color match. If you can get a good one, it can be practically invisible. Far easier/better than trying to do the entire bottom of the tub, because trying to get _that_ faired properly, hidden edge or not, will be almost impossible.

[We term this "mexican prison wall finish"]

Concrete only fully cures after 30 days. You don't have to wait that long to use it. Epoxy is going to be at 95% or better in 3-4 days. Especially if you tickle it along with a heat gun.

[The West Systems instruction book is quite good.]

It's more important to ensure you get the proportions right. If you don't, it never cures.

There's no way epoxy will break bond off a fiberglass tub prepped as I've suggested. Yes, the original crack is a weak point. Depends on why it cracked. And is why I suggested a thick/sloppy patch on the backside too if you can get at it.

[Jim Yanik]

[e-mail] (Chris Lewis) wrote in news: [e-mail]:

Compared to a small patch in the middle of the tub bottom? THAT is going to show much more than a whole tub-bottom covering,even if you match the color and smooth it perfectly. It WILL still be a raised patch on the flat tub bottom. IMO,MORE obvious than a whole-bottom covering.

and fairing a whole-bottom covering is NOT "almost impossible".

SO WHAT? we ain't talking about concrete.

Don't bet on it.

So is System Three's Epoxy Book.

Agreed.

A backside patch is the best way,of course.