How to fill a 1" hole through transom?

[96TL]

I tried filling in an old transducer cable hole on my friend's 2520 last week. It's straight through the transom, and about 1" wide. First I wet the hole out with neat epoxy, and then I filled it with thickened epoxy (Cabosil). It didn't come out that great. The epoxy cured with a bunch of voids in it.

Am I going about this the right way? Should I plug it with an epoxy coated wooden dowel instead? Once I get the dowel in there, and can cover it completely with thickened epoxy. Or should I attempt doing it with just epoxy again? I've never tried filling a hole this wide before.

Thanks guys.

 

[DaleH]

Above the waterline? If so and if you want to gelcoat it, I'd stuff a dowel in there that's covered with poly or vinylester resin.

* I too would wet the core with thinned epoxy and let cure.
* ROUGH up the inside of the hole or leave wood rough when you coat with the thinned epoxy, this will allow the poly/vinyl resin to mechanically bond to the epoxy.
* Take hardwood dowel somewhat smaller than the hole and make it a smooth fit WITHOUT pounding it in place, as you don't want to squeeze out all the resin.
* Add grooves and/or slots around OD of the dowel to hold/trap resin.
* Size length to leave 1/8" or less on each side
* Goop up with resin and insert - let kick/harden
* If you need filler, use Formula 27
* Gelcoat on top

Done ...

 

[96TL]

Dale, would epoxy be okay instead of poly or vinylester resin? I have no experience with either. If not, we might have to get a pro involved. Hard to come by in our area though.

And where can I get a dowel? Does it have to be a particular kind of wood?

Thanks!

 

[DaleH]

It can be tough gelcoating over epoxy, though some say it can be done. PM me your email, I have an article on 'how to' do it.

Whereas that hole isn't going to be structural, I'd go for ease of gelcoating over toughness myself.

A good wood place would have hardwood (read non raman wood) dowels.

 

[96TL]

I've gelcoated over epoxy a few times without any problems. I remove all the blush first, and then rough up the surface a bit.

Jamestown Distributors sells dowels made of ash, teak, cedar, pine, SA mahogany, Phillipine mahogany, fir, cherry, oak and spruce. Would any of those be okay?

 

[grouperjim]

Dom:

Just installed a transducer in the OtherLine's 2520. He still has the plug. Why don't PM him and glass his plug into your buddies boat.

jim

 

[tara11]

I still have the 2" one I took out of mine for my transducer install , but as I type this, it is a 2", so to big !

 

[TheOtherLine]

Dom:

Just installed a transducer in the OtherLine's 2520. He still has the plug. Why don't PM him and glass his plug into your buddies boat.

jim

96TL; Yep, I think I still have it. If you want it, just let me know and I'll go looking for it and send it to you.

 

[Porkchunker]

Now that is what I call helpful. One ParkerNation member uses a hole saw to drill out a 2" plug for a transducer, and gives the plug to another ParkerNation member to plug an old transducer hole.

What a great site.

Dave

aka

 

[96TL]

Dom:

Just installed a transducer in the OtherLine's 2520. He still has the plug. Why don't PM him and glass his plug into your buddies boat.

jim

96TL; Yep, I think I still have it. If you want it, just let me know and I'll go looking for it and send it to you.

TheOtherLine, whats the diameter of the plug? I had my friend measure the hole yesterday and its 7/8". Thanks!

Thanks for the help everyone!!! I love CP!!!

Dom 8)

 

[grouperjim]

About 2.25" by 5/8 thick if I remember correctly. You could put it in a vice and cut to size.

 

[gw204]

The epoxy cured with a bunch of voids in it. .

How did you get the thickened epoxy into the hole? If you tried just pressing it in with a mixing stick, that's your problem. You really have to inject it with a syringe.

I did the exact same thing on my Grady. Here's the process I used:

1. Rough up the edges of the hole to get to clean glass/wood.
2. Put a piece (or pieces) of blue painters tape over the outside of the hole. You can make the tape flush, bulge out or push in a little depending on how you plan to finish.
3. Paint over the everything with unthickened epoxy.
4. Using a syring, inject the thickened epoxy into the hole from inside the boat. Push the syring in until it hits the tape. As you inject the stuff, move the syring around to completely fill the width of hole and pull it out slowly as the hole fills up depth wise. This is the way to avoid voids.
5. Once it's full, put more tape over the inside.
6. Allow to cure and finish off as desired.

Gelcoating over epoxy works fine. I've done it many, many times. Just rough up the surface w/ 80 grit and wash w/ acetone.

Any time I do a repair like this, I aways inject my thickened epoxy before the unthickened cures. Thay way you get both a mechanical and chemical bond. It's much stronger than just a mechanical.

 

[TheOtherLine]

96TL: Sorry, I've been swamped. Anyway, Grouper Jim answered the question. Let me know if you want me to go look for it.

Actually, I have the piece I cut out of the helm for the 4212. You could cut just about any size plug(s) you want out of that.

 

[96TL]

I actually did it yesterday using a plug made out of a wooden dowel. I cut each side to the proper angle. We'll see how it came out today, but it looked good yesterday!

Thanks for the offer though. 8)

 

[TheOtherLine]

Well, glad you got it done. Offer still stands for anyone who needs a plug.
Give me the size and I will cut it out for you and send it out.