Repairing a hairline crack in bathtub

Acrylic?

If it's GRP then GRP patch on the back, presumably.

I tried a resin repair with plenty of fibreglass mat. Worked great for a while then cracked off. Tried it again with much bigger mat area & more reinforcement. Same thing followed. You're screwed.

NT

In message , snipped-for-privacy@gmail.com writes

Would epoxy resin rather than the car repair type resin work? Certainly it does inside wooden boats, and to repair a crack in a fiberglass dinghy. In the outdoors, on the upturned dinghy, it has yellowed significantly, though.

cast iron?

Probably bugger up the finish on the acrylic though.

Duck tape?

Owain

Check the underside of the bath.

To give the base some strength the manufactures glue/bond a sheet of chipboard to the base of the bath. Sometimes this board is exposed and sometime this board is further covered in a layer of fibre glass/resin.

Whilst dry this board serves its purpose but as soon as it gets wet it has the strength of soggy Weetabix. Once the strength goes the base of the bath can flex a lot v v more and your crack may widen and let through more water. I have the tee shirt! As a precaution I recommend that you perhaps prop up the base using scrap wood wedged between the bath base and the floor.

Is one side of the crack at a higher surface level than the other side of the crack indicating that the underlying strengthening fibre shell may have also cracked?

With a hairline crack the filler probably needs to be very liquid for it to enter a thin crack by capillary action.

When I broke up my old acrylic bath and disposed of it in 3 rubble sacks the construction appeared to be a 1/8th inch thick one piece molding of the inner bath strengthened with layers of glass fibre/resin and with the chipboard base glued on afterwards. This inner layer was very brittle, albeit the bath was around 20 years old.

Creeping Crack Cure?

Tim

In message , snipped-for-privacy@gowanhill.com writes

Although it's not very elegant, that's a fairly good idea (although don't choose a cheap brand). If (when) it does eventually start to come adrift, it's easily renewed.

I tend to agree with those who say you are probably stuffed and looking at a new bathtub - ouch!

And I agree with those saying that if you attempt a repair (knowing the probability of long-term success is pretty low) supporting it from underneath so that it can't move or flex again is essential.

I would go for an acrylic solvent myself. Yes, I think I would drill a tiny hole at each end of the crack and then maybe dissolve the shavings in the clear solvent to boost the colour. It's never going to look perfect again but that might help.

IIRC pure ether dissolves acrylic but nowadays I think you can buy acrylic welding solutions which contain the solvent loaded with dissolved acrylic. A quick google on the subject brings up a few solutions (sorry about the pun).

Hope this helps. Do let us know what you decide to do and how it works out.

Nick

DENSO tape underneath .......should last a long time and waterproof .......

just slap it on it will stick...wear gloves ...

DUCT tape.

I bonded srap ply to te sides of mine as well using car body filler when I installed them. And kept on adding till there was no flex left.

I repaired one in a composite sink as a temp measure with fibre glass resin and Matt from Halfords.

The crack was quite large, but hairline (a hot cooking pot was dropped into the sink). It sealed fine until we replaced the sink.

Some brands are indeed called 'duck tape'!

And should be banned

next the duck sticky tape company will be imprisoned for hate speech toward ducks.

ISTR that it is chloroform which dissolves acrylic and is the solvent in acrylic glues.