PDA

View Full Version : Plywood Repairs



pdevol
10-08-2018, 07:42 PM
Have a 14í plywood sloop with a leak in the transom and possible along dagger board tunnel, see pictures (tunnel and upside transom). Need advice on how to fix. Previous owner used what looks like epoxy. Iím use to kayaks and composite hulls; plywood is all new to me. Can someone steer me in right right direction?
24238 24237

Thanks,
Phil

2dogsnight
10-08-2018, 08:44 PM
looks like may need a new transom.....
remove paint to see what is going on there

skuthorp
10-08-2018, 09:07 PM
New transom is easier than repairs, cut a little oversize unless you are a better woodworker than me, and don't presume that it's absolutely symmetrical. I am refurbishing a 1961 sailing dinghy that is from the look of that, in better nick. I'd have a careful look at the framing in the area, and get rid of the paint if you can. There might be some ugly stuff under those patchings as it's an area where water is inclined to pool. I replaced the whole transom and rear deck framing as it was easier than a repair. It's a plank bottom I see? A new transom and framing will enable you to get a good look at the plank ends as well.

I'm no expert I might add, it's just that I'm doing the same repair as you more or less.

pdevol
10-09-2018, 08:05 PM
looks like may need a new transom.....
remove paint to see what is going on there

When I remove the blue paint (assuming you mean on the lower mount for the tiller), what should I be looking for? I can see that there has been some fill work done there. If the transom needs to be replaced, do I need to remove the screws on the transom or might I suspect there is there some additional added as well? After that do I cut a new piece of plywood a bit over size, seal and attach then trim to size. Any recommendations on special type/grade of plywood and sealant?

thanks,
Phil

Woxbox
10-09-2018, 08:10 PM
As above, don't be timid. Just start chopping away at anything that's suspect. The bottom planking next to the transom needs to be examined, too. Tapping the wood with a plastic mallet and poking at it with an awl is also telling. If the mallet lands with a thud or the awl sinks in, you have wood that needs to come out.

You want marine grade plywood if you can find it. I don't know what sources are available in your area.

pdevol
10-09-2018, 08:32 PM
Wouls a picture of the inside help? I did notice a small soft spot (size of dime) in center rear of the cockpit where the transom attached to rest of hull. If the transom needs to be replaced, do I need to remove the screws on the transom or might I suspect there is there some additional added as well?

After that do I cut a new piece of plywood a bit over size, seal and attach then trim to size. Any recommendations on special type/grade of plywood an d sealant?24283

thanks,
Phil

gypsie
10-09-2018, 11:20 PM
I think one step at a time.
Everything seems hidden under paint, old varnish and goop. Start sanding/grinding/scraping that back to the wood so you can have a close look.
It's probably worth doing this in any case so you can paint/varnish it back up properly - it won't be a wasted effort.

pdevol
10-11-2018, 10:51 AM
Will be a State XC meet this weekend but will work on the transom in this area this coming week and post what I find-thank you.

pdevol
10-17-2018, 11:36 AM
Here’s a picture of the sanded transom. Wood looks good except for some delamination and a rough spot or two. Can I use CPES to penetrate then epoxy fill to fix? Or do you have further suggestions.
24672

gypsie
10-18-2018, 10:41 PM
I'm not sure that ply looks all that good. Is it delaminating?

My thoughts without seeing the inside sanded back;

Sand back the inside of the hull, to about 6 inches out from the transom.
Sand back the outside of the hull about a foot back.
Sand all transom inside and out, and anything attached to it (pic #1)
And hour or so of work.

Fill those cracks with thickened epoxy.
Create a fillet of thickened epoxy around the inside join of the transom/hull - and if you're feeling keen, glass tape over that.
Sand smooth-ish once set.

Optional - run a small sheet of fiber glass on the underside of the hull where sanded, epoxied on. Add a couple of layers of epoxy as it goes off.
Coat everything you've sanded in epoxy - twice.
(Basically make an epoxy glove for the whole aft section about 6" to 12" from the transom).

Paint.


Small touches of epoxy won't last long. The timber will expand and contract and shake the epoxy off reasonably quickly.