Repair screw holes on transom

[Picflight]

Repair screw holes on transom (PICS)

I am looking for steps, materials to use to fill holes on the transom left by a transducer removal.

I have done the reading, video viewing on the use of epoxy. I prefer to use polyester resin so that I can finally gelcoat over it.

If you have done such a repair with polyester resin, I would like to hear how it was done. How it is holding up.

All the instructions I have read use epoxy. I would like to stick with the material the boat was made out of, hence the desire to use polyester. It might be the more difficult route to take but I am willing to explore it.

Thanks.

Filled with Epoxy but not liking it. Top left needs rework.

 

[centerline]

lots of trouble for such small holes... I would recommend 4 countersunk bolts with nylocs, a countersink and a small amount of 3M 4200 or 5200...

carefully countersink the holes so the bolts fit flush, dab them with sealer and install... 15 minutes work and it will last a lifetime....

 

[Chris Patterson]

It's not more difficult, it is very simple with poly. Putting in the epoxy first did you no favors, but the poly will outlast everyone here by far. Yes the boat is built with it, and there is nothing in the world wrong with using it. When we stripped the teak decks off of another rotting far east boat, (If you lose sight of your teak decks, this will be you too), we used gallons of polyester resin. It would have cost a kings ransom in epoxy, and it is JUST NOT required for small repairs, tabbing bulkheads, or other "lighter duty" jobs. Yes, I keep a gallon can of epoxy in my work truck and use it commonly. But since the 'recent' hoopla about epoxy, now everyone seems to think that poly resin is going to dissolve in water or something. It's great stuff, easy to work, can cover it later, (which you'll rarely do successfully with epoxy), and cheap. It's got so damn bad with everyone running out and buying structural grade adhesives, ie: epoxies, that on the yard we're afraid to use poly too much simply because we don't know if a P.O. used epoxy on it before.

Epoxy is great stuff. I use it all the time. But folks, there's no use running out and buying a fully automatic AK47 to hunt rabbits..

 

[Picflight]

Chris, what procedure would you follow to do holes like this with polyester resin?

 

[Old Skool Neil]

Bondo. It's what the boat manufacturers used and is polyester based. Lightly countersink the holes first.

Another option that requires a little more finesse is to thicken matching gelcoat with Cabosil to make a color matched putty, add a drop or two of surfacing agent and catalyze accordingly. Sand flat, finishing with 600 grit wet and buff. Those holes will disappear.

BTW, I would never make the above recommendations if I had not done them myself several times.

 

[Captn TJ]

Bondo. It's what the boat manufacturers used and is polyester based. Lightly countersink the holes first. Another option that requires a little more finesse is to thicken matching gelcoat with Cabosil to make a color matched putty, add a drop or two of surfacing agent and catalyze accordingly. Sand flat, finishing with 600 grit wet and buff. Those holes will disappear.

Bondo - underwater??? First I've heard of that.

 

[Old Skool Neil]

Oh no - no Bondo underwater, we never used it there. Picflight's holes are above the waterline however.

 

[Chris Patterson]

There ya go man. I'd take Neil's fix to the bank.

 

[Scotty C-M]

I agree with Neil's second option. Easy to do! Use tape to make a funnel to pour the wet material into the holes. Tape the inside. (Don't try to put tape on top of any "wet" areas - it won't hold). I've (partially) filled the "funnel" and then taped it closed so that I only have a small amount to sand off. I would never use bondo - it cracks.

 

[Picflight]

Oh no - no Bondo underwater, we never used it there. Picflight's holes are above the waterline however.

Holes are under water, that part of the transom is underwater. That's the speedometer & transducer holes.

 

[Old Skool Neil]

Well then, I completely misunderstood the picture. Bondo and Cabosil are off the table, sorry.

 

[mitiempo]

I would use epoxy as it is easier to use than polyester and it's adhesion to cured polyester is better. If you want to gelcoat over the epoxy you can.
http://www.westsystem.com/ss/polyester-over-epoxy/

 

[Picflight]

I am thinking of making some room in the holes, drill sand to a depth of ~3-4mm to get just below the level of the gelcoat.

Mix some polyester resin with pieces of fiberglass mat, shredded, catalyze and stuff in the holes to just about the inner level of the gelcoat. Let cure for 24 hours.

Mix gel coat with cabosil 50/50 press into hole and spray with PVA or cover with wax paper.

Polyester all the way, how will this technique fair?

 

[Chris Patterson]

That will work great. Thing is, simply because I keep epoxy with me always, that is probably how I would handle it. For whatever reason, as many times as I have used it, that colloidal silica is a bear for me to mix. Maybe it's just impatience, but I get frustrated with it. All that aside, it's a bulletproof repair no doubt. Oh yeah when you get the epoxy stuffed in the holes like you want it, put a common piece of ductape over the hole to keep the epoxy in. The epoxy will not stick to the sticky side of the tape, and taken off in under 24 won't leave a mess of tape glue. I tried wax paper and everything I could think of, and in doing a smaller repair the idea of running out and buying formica for forming is ridiculous for me. Especially small holes.

 

[Old Skool Neil]

If these holes are below the waterline where only the fish will see them why all the fuss over cosmetics? It seems to me centerline's suggestion of filling them with machine screws and caulking would be the most expedient.

And why no bottom paint? Without it in Channel Islands you'll have growth within a matter of days.

 

[Picflight]

Neil, I like to keep things as original as possible.

 

[Old Skool Neil]

I like to keep things as original as possible.

A worthy goal indeed.