Filling holes in the transom

[robmcg]

Thinking ahead, I need to change the bathing ladder on the back of our transom. It will leave 4 holes through the transom of probably 5mm diameter. Obviously, I need to make good these holes but dont want to just fill them with gelcoat filler - so how would you go about filling them, what materials would you use for a good job and where would you source these from? Just want to do a decent job not bob-a-job!!!!

 

[rob2]

I'm not going to pretend I have a definitive answer! My ladder broke too and no-one seems to make a replacement the same width - or the rung configuration I want. The main things I'm considering is water-tightness and aesthetics, I don't think strength comes into it at all.

Luckily my boat is old enough that a few repairs and scars won't look out of place and anyway the gelcoat is a sort of creamy off-white, so it is unlikely that I would succeed in matching the colour. If I'm lucky, the new mountings might overlap the old position so the repair won't show, but it's unlikely. I was considering glueing an oversize backing pad inside the transom so that it covers the old holes and take the new ones. With that as a former, I would chamfer the outside edges of the holes and simply fill them with epoxy and finish off with some gelcoat filler. I could also use a matching wooden pad on the outside to cover the blemishes, but the extra maintenance doesn't seem worth it - maybe a nylon pad would do it, though.

I'm still considering the options, luckily I feel the aesthetics are most difficult. A plugged hole in the transom isn't going to leak or weaken the boat.

Rob.

 

[maby]

If they really are just 5mm diameter, I think you just need to fill them out with an epoxy paste such as Plastic Padding, leaving a millimetre or so depth that you can finish off with gelcoat filler. Smooth it off nicely with a spatula, let it set well, then buff it in with some suitable cutting compound.

 

[CreakyDecks]

Without spending a huge amount of time and effort it will look obvious what you have done, so it might be better just putting stainless buttonhead screws in the holes!

 

[maby]

Without spending a huge amount of time and effort it will look obvious what you have done, so it might be better just putting stainless buttonhead screws in the holes!

On the transom, I'm not sure that is true -it's an area that you don't look at from very close up and the holes he describes arevery small. I would think that if he plugs the holes, then skims over with gelcoat filler, it should be unnoticeable to someone that doesn't know it's been done.

 

[VicS]

I would do ( have done) as suggested above.

Fill with some filler such as Plastic Padding or Isopon .. use the hard type I think rather than the elastic type.

As suggested leave it a mm blow the surrounding surface or drill/grind it out to a shallow depression and then finish off with gel-coat filler.

Left slightly proud and sanded back with increasingly finer grades of wet and dry then a rubbing compound and finally a wax polish should produce an almost undetectable repair. Its no big deal even if it is not totally invisible.

A layer of glass mat bonded inside first may give something solid to fill against.

 

[vyv_cox]

Without spending a huge amount of time and effort it will look obvious what you have done, so it might be better just putting stainless buttonhead screws in the holes!

I did exactly that when I removed my Windpilot. Looks far better than the small professional gelcoat repair done on the hull. Having been a colour matcher in a previous life I know how difficult it is to get a good match, even with full pigment resources and a lot of training.

 

[robmcg]

The inside of the transom has been painted in grey bilge paint. Am I right to think this needs to be abraded off if I am to use any fiberglass. I ask because I am going to fit a hydrovane and will need to glass in some backing pads to distribute the load from the brackets. Current thinking is to sikaflex some marine ply to the inside of the transom where required and glass over to bond it all in and keep the ply protected. Same applies to bonding glass mat behind the holes left by the departing boarding ladder.

 

[maby]

I think it's safe to say that you should remove the paint before attaching the backing panel - the chances of getting a good, lasting bond onto the painted surface are poor.

 

[V1701]

I removed a bathing ladder and an outboard bracket before fitting my Navik windvane and used Plastic Padding Glass Fibre Filler on the inside (which is not painted) and gelcoat filler on the outside...

 

[gjgm]

above the waterline,doesnt matter much. Below, you need to be sure there is no chance of any water getting in especially if the transom is strengthened with ply.
Isopon is probably fine, but west systems (for example) do a mini repair kit for about £15 with resin hardener tape and filler. Chandleries usually have them.
They also do some superb guides to grp/resin work. Some might be on their web sites, but otherwise some good tips in their various guides for about £5.
Small note on epoxies.. ther mixing % is far far more critical than polyester resins.

 

[Elessar]

Thinking ahead, I need to change the bathing ladder on the back of our transom. It will leave 4 holes through the transom of probably 5mm diameter. Obviously, I need to make good these holes but dont want to just fill them with gelcoat filler - so how would you go about filling them, what materials would you use for a good job and where would you source these from? Just want to do a decent job not bob-a-job!!!!

Solvent free epoxy, thickened with a thickening agent. These filler balls are widely available in chandleries, add the right amount to the epoxy like making porridge. Note gjgm's sound advice on mixing the epoxy itself.

If you're worried about the aesthetics, leave the filler a mm below the surface, and add gelcoat. Sellotape over the gelcoat so you exclude the air to make it cure. Sand it fair with a sanding block, then use increasingly fine sandpaper, then cut, then wax.

Getting the colour match right is hard, but get it close and small holes won't be terrible.

If you go the bolt route, bed them in polyurethane sealant, NOT silicone.