Should a Metal or Wood Transom be used?

Thewetsnapper

Recruit
Joined
Jul 9, 2013
Messages
3
Hi everyone,

I'm currently replacing a rotten transom on a 1973 Aquarian bowrider and need to determine whether or not to replace it with a wooden or metal transom. Here is the situation...

The boat has about a 1/4 or 1/3 inch of healthy looking fibreglass that is still supporting most of the motor weight and I would like to avoid taking the entire wooden transom out of the inside of the boat. I know this sounds lazy but it is not easy to get to the transom and I would have to lay flat on my stomach and cut it out from underneath the bottom end of the boat. This would probably take me 10 hours to cut out with chisels, drummel etc. and I don't want to rush or I might harm the hull. I'll upload a picture tonight if possible.

Anyways, I'm thinking that it might just be easier to leave the wooden carcass of the transom inside the boat (because its not visible) and simply add a steel/metal plate on the outside of the boat. I would of course, cut out a space around where the bolts attach and make sure that the motor is not attached to the rotten area.

Does anyone see any problem with this?

Secondly, in terms of selecting the right size/shape for a metal plate, does anyone have advice? I've tried looking this up but for some reason it is a very hard topic to research.

*The transom will be supporting a 50hp 1973 Mercury Thunderbolt

Thanks!
 

gm280

Supreme Mariner
Joined
Jun 26, 2011
Messages
14,605
Re: Should a Metal or Wood Transom be used?

First of all welcome to iboats :welcome: always good to have another boater aboard.

Personally I would remove anything and everything impeding my effort to completely remove the entire transom and replace it all the proper way. Reason? Because it will not be as solid or safe as a new entire replacement one will. Think of it this way, do whatever it takes to do the project correct from the start and you will never regret it or worry about it from now on. Short-cutting the effort is not conducive to a quality safe boat... Safety has to come first. BUT, this is just my opinion and it is your project... There is a lot of very good help on these forums, but I don't think anybody will tell you a partial replacement is the way to go... Could be wrong, but I seriously don't think so...
 

jerryjerry05

Supreme Mariner
Joined
May 7, 2008
Messages
18,089
Re: Should a Metal or Wood Transom be used?

Just adding a metal plate won't replace the strength a wood transom gives.
Unless the plate was 1/2in al.
Then you'd have to brace it anyway.
Remove the motor and all the pieces.
Get t ewood out and replace with marine plywood,depending on the transom usually 3 pieces of 1/2" and glued together.
 

saginawbayboater

Senior Chief Petty Officer
Joined
Mar 8, 2012
Messages
677
Re: Should a Metal or Wood Transom be used?

I would not repair your boat that way!! It is not SAFE!! I do know a guy that did just that. :facepalm:

Fix it right and it will last for years to come.
 

pckeen

Commander
Joined
Jun 20, 2012
Messages
2,067
Re: Should a Metal or Wood Transom be used?

Ditto. Would you trust a rotten wood bridge with a metal plate over the top if the rot?
 

crovowen

Seaman Apprentice
Joined
Jun 1, 2012
Messages
49
Re: Should a Metal or Wood Transom be used?

here is what happens when you use a metal plate-
P6290026_zps9e868ef6.jpg
looks good, right?
P6300001_zps668c7c21.jpg
this is what you will end up with- take the plunge- FIX IT RIGHT!!!
 

Watermann

Starmada Splash of the Year 2014
Joined
Jan 12, 2013
Messages
13,822
Re: Should a Metal or Wood Transom be used?

Somebody stuffed a microphone in your drain plug :D

BTW, I need that left trim cylinder.

:laugh: I think that's a livewell pump intake with a strainer on it. You could always try humming a few bars into it tho... I can see it now, an Iboats hosted rotten transom Karaoke night!

Oh yeah sorry uhh... wetsnapper ... forgot to cast my vote on the patch job... NO, I agree with the do it right crowd.
 

matt167

Rear Admiral
Joined
Sep 27, 2012
Messages
4,180
Re: Should a Metal or Wood Transom be used?

I could not get leverage on this motor to pull it over with the recoil because the engine bounced so hard with the flexing transom. When I towed this boat home, It's a good thing it had a transom saver on it because otherwise it would have dropped that 650 on the ground.. My grandfather put that 'patch' on in the late 1990's and I don't think the boat was ever used with the patch ( good thing too ).. Fix it right or don't let your faimly and friends on-board
24v791t.jpg
[/IMG]
 

saginawbayboater

Senior Chief Petty Officer
Joined
Mar 8, 2012
Messages
677
Re: Should a Metal or Wood Transom be used?

I think that's a livewell pump intake with a strainer on it. You could always try humming a few bars into it tho... I can see it now, an Iboats hosted rotten transom Karaoke night!

Row Row Row your rotten boat gently down the stream. Throw your family overboard ad listen to them scream. Oh, Sorry!:D
 

crovowen

Seaman Apprentice
Joined
Jun 1, 2012
Messages
49
Re: Should a Metal or Wood Transom be used?

i was thinkin more along the line of 'tiny bubbles'....
 

jigngrub

Fleet Admiral
Joined
Mar 19, 2011
Messages
8,155
Re: Should a Metal or Wood Transom be used?

does anyone have advice? I've tried looking this up but for some reason it is a very hard topic to research.

It's a hard topic to reasearch because it's a very bad idea.

It's about like taking a set of bald tires off your car and putting another set of bald tires instead of new ones.
 

Thewetsnapper

Recruit
Joined
Jul 9, 2013
Messages
3
Re: Should a Metal or Wood Transom be used?

Well thanks for the timely feedback. To be clear though, I never said that I was going to patch over rotten wood. I was thinking of cutting off an area of the rotten material and inserting a metal plate.

Either way, I got the right tool for the job (a dremmel) and cut the damned thing out over the weekend. It was quiet a pain (especially in 30 degrees celcius) but it was done. I'll be putting in a wooden transom sometime soon.

So my new question is how long do you think an appropriately sealed treated plywood would last in comparison to marine grade? On the advice of a local lumber store, I am considering using a treated piece of fir plywood that is for exterior purposes. I would then be covering all edges with an epoxy to fill gaps and make sure it is solidly attached to the boat then afterwards I will be covering it with fibreglass.

Any guesses as to how long this should last in comparison to using marine grade? I know its hard to say but I'm just curious as to the extent of the difference in these conditions.

All bolts/holes will be sealed with silicone
And the boat will not be docked for extended periods. It goes out for the day/weekend then back in the yard.
 

GT1000000

Rear Admiral
Joined
Jul 13, 2011
Messages
4,916
Re: Should a Metal or Wood Transom be used?

First of all, unless the treated wood is kiln dried, don't use it...treated lumber is usually wet with chemicals that take a long while to dry out and may prevent good adhesion with the resin...
Any good quality, exterior grade plywood, properly sealed with resin and cloth can last well over two decades if the boat is properly cared for...meaning that the plug gets pulled after every outing, it is stored dry and covered from the elements...
Don't use silicone...
Use a Marine Grade sealant such as 3M 4200/5200 or its equivalent...they are formulated for the Marine Environment.
Good Luck and Have Fun!
GT1M:)
 

saginawbayboater

Senior Chief Petty Officer
Joined
Mar 8, 2012
Messages
677
Re: Should a Metal or Wood Transom be used?

Thewetsnapper we need to see some pictures. If we can see what you are working on it's easier to understand. Also there is a saying around here if we can't see it it didn't really happen! :peace:
 
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