How to remove epoxy from inside hull.

[eddystone]

The in-hull transducer fitted to my boat leaked so after endless unsuccessful attempts to seal it up with Captain whatsits creeping crevice cure and marine sealant I finally solved the problem with Marine Epoxy filler. Problem is I now need to remove the transducer housing to replace it with a new one and I want to use that position because I know it works. I presume the inside of the hull is covered with flowcoat rather than gelcoat but I'm concerned in chipping off the epoxy I might inadvertently remove chunks of layup. The best way I can think of although very slow (and with suitable face mask) is to grind it off with a Dremel and then make good/smooth with gelcoat filler.
Better way?

 

[coopec]

I think the only way to get the epoxy off is to sand it in some way. Are you really going to damage the inside of the hull? If I thought I had I'd epoxy a few layers of glass cloth where I thought I'd done the damage.

I used flowcoat once and I would never use it again. It is expensive and I don't think it does anything that RustGuard (or Killrust) epoxy paint. The Saleswoman at Bunnings put me onto it when she said "you can buy the same paint in the Marine Section at double the cost"

 

[Poignard]

Rather than have dust everywhere and in my lungs, I would take it off with a mallet and a sharp chisel. A few moments work.

Any collateral damage to the hull lay-up can easily be made good with epoxy.

If that doesn't appeal, an oscillating multitool such as Fein, Bosch etc. sell with a saw blade fitted would be quicker and less messy than abrading it off.

https://www.toolstation.com/bauker-...MI0svlmNzp5QIVxbHtCh1bBwLOEAQYASABEgK_4fD_BwE

 

[C08]

I tried to remove epoxy from bedding in an in hull depth transducer with a sharp chisel and it came away with about 10mm of the hull layup. I then had to build up the hull thickness so I would go with sanding down with an angle or finger grinder. Glue the new one down with something less adhering than epoxy! I used a polysuphide sealant for the new transducer and it is fine.

 

[eddystone]

Like the idea of the oscillating multitool but will try with various cutting and grinding tools on the Dremel first. Yes entirely agree about the risk from airborne fibres - will make sure I'm using the right type of mask.

 

[Spirit (of Glenans)]

Like the idea of the oscillating multitool but will try with various cutting and grinding tools on the Dremel first. Yes entirely agree about the risk from airborne fibres - will make sure I'm using the right type of mask.

IMHO an angle grinder would be better as the job would be finished quicker, resulting in less lungfuls of dust.

 

[Boathook]

Like the idea of the oscillating multitool but will try with various cutting and grinding tools on the Dremel first. Yes entirely agree about the risk from airborne fibres - will make sure I'm using the right type of mask.

I try and have my garage vacuum cleaner 'running' sucking up any dust that I create. Some of the multitools have the fittings to attach vacuum clean hoses, etc. I also site, if possible, my vacuum outside the boat in case dust gets through the filter.

 

[thinwater]

Vacuum attachment. Every boater should have them, not just for you, but to reduce boatyard dust. And run a second vacuum if you like. Should only take moments.

 

[Stemar]

IMHO an angle grinder would be better as the job would be finished quicker, resulting in less lungfuls of dust.

I disagree. An angle grinder is a wonderful weapon of mass destruction, while being capable of delicate work in the right hands but, because of the speed of the disc, dust goes everywhere. The multitool doesn't project dust in the same way.

If there's any sort of finish - gelcoat, flowcoat or paint - on the inside of the hull, the very strong likelihood is that the finish will lift from the layup without a problem apart from the need to make good afterwards, but the worst case scenario is that you'll need to epoxy a bit of mat down. If it does come down to that, you'll find more than you'll ever need to know about how to do it here: https://www.westsystem.com/instruction-2/

 

[Jaguar568]

I was told by a boat builder to use a hot air gun and a scraper, tried it and it does work !

 

[Poignard]

I was told by a boat builder to use a hot air gun and a scraper, tried it and it does work !

Yes, why not?

Come to think of it, I clean dried epoxy off plastic spreaders easily with boiling water.

 

[eddystone]

I will no doubt end up using several of these approaches and give some feedback in the new year

 

[guardian]

I was told by a boat builder to use a hot air gun and a scraper, tried it and it does work !

...............but you'll die of old age, mask on, eye protection on, disposable suit on then put a 24grit flap disc on your 100mm grinder and cut it all away in seconds.............just a thought.

 

[Akestor]

A chisel like this and a mallet with light strokes will brake the epoxy eventually! if you do it gently i dont think there will be any damage except the topcoat will be removed which is not a damage... this will happen with any approach though.