Quick Question - Type of Wood For Transom

adamkosecki

Seaman Apprentice
Joined
Jul 1, 2004
Messages
37
Quick question- I'm going to be buying wood to rebuild my transom tomorrow afternoon. It seems like everyone on here recommends outdoor grade plywood, but I was hoping to use something I could finish with varnish. My dash, floors, and seats are all pine with about 12 coats of spar varnish. They look like they were dipped in glass. I think it would look really sharp if my transom matched.

Questions:

1. Will 3/4" pine be strong enough for the transom?
2. Will finishing it with spar varnish hold up?

Thanks!
Adam
 

Attachments

  • Boat2.jpg
    Boat2.jpg
    73.6 KB · Views: 0
  • boat6.jpg
    boat6.jpg
    48.7 KB · Views: 0

oops!

Supreme Mariner
Joined
Oct 18, 2007
Messages
12,932
Re: Quick Question - Type of Wood For Transom

uh.....nope and nope....

the resto forum guys have this down pat.......pine is a soft wood.

the goal for the varnish is not just to waterproof....but to add stregnth and to "lock" it to the hull.....

if you use clear sealing epoxy you might get the desired effect....but with out glass in there you are substituting looks for stregnth where its needed
 

5150abf

Vice Admiral
Joined
Aug 12, 2007
Messages
5,808
Re: Quick Question - Type of Wood For Transom

3/4 outdoor ply wood doubled up and glued together, I used Gorilla glue but there are alot products you can use.

Cut out your 2 peices, glue them together and then hit the whole thing with Thompsons water seal paying close attention to the edges.
 

SS MAYFLOAT

Admiral
Joined
May 17, 2001
Messages
6,372
Re: Quick Question - Type of Wood For Transom

I used good ole marine ply when I replaced my transom in 2006. It has more ply's for added strength. However, mine is a 27' and it needed to be as strong as I could get it.
 

adamkosecki

Seaman Apprentice
Joined
Jul 1, 2004
Messages
37
Re: Quick Question - Type of Wood For Transom

3/4 outdoor ply wood doubled up and glued together, I used Gorilla glue but there are alot products you can use.

Cut out your 2 peices, glue them together and then hit the whole thing with Thompsons water seal paying close attention to the edges.

ok - I actually read another post that you explained this method. The thing is, I cannot use two pieces b/c the slot is only 3/4" thick that it slides into. See attached pictures. The side mounting brackets could be moved back to accommodate for a wider transom, but the bottom/middle one cannot be adjusted.

Will I be ok with 3/4" ply? That's what it was originally set up with, but maybe I should use something stronger?

Thanks! All your help is really appreciated.
 

Attachments

  • transom-mount-1.jpg
    transom-mount-1.jpg
    71.4 KB · Views: 0
  • transom-mount-2.jpg
    transom-mount-2.jpg
    49.4 KB · Views: 0

Joe_the_boatman

Chief Petty Officer
Joined
Apr 14, 2005
Messages
482
Re: Quick Question - Type of Wood For Transom

I'd use pressure treated 3/4" plywood, coated in epoxy, then painted.

Maybe cover the plywood w/ a sheet of laminate, then varnish over? Either way, keep the pressure treated wood insulated from any aluminum. It'll eat it over time.

Helm and deck look good though.
 

oops!

Supreme Mariner
Joined
Oct 18, 2007
Messages
12,932
Re: Quick Question - Type of Wood For Transom

if you use any water seal products like thompsons....or other off the shelf product in a marine enviroment...........youll be sorry.

really.....use the search feature......there is a gazillion thredads on theis in the resto forum....pros, cons......if you want to fix it correctly....we can help you....but only if you actually use the info given here
 

adamkosecki

Seaman Apprentice
Joined
Jul 1, 2004
Messages
37
Re: Quick Question - Type of Wood For Transom

if you use any water seal products like thompsons....or other off the shelf product in a marine enviroment...........youll be sorry.

I read this in another thread and did not plan on doing that.

really.....use the search feature......there is a gazillion thredads on theis in the resto forum....pros, cons......if you want to fix it correctly....we can help you....but only if you actually use the info given here

I understand that, that's why I'm talking to you and asking for help. I did my search research before posting. Some of the questions I'm asking are more specific to my boat than the general results I have already found.

I'd use pressure treated 3/4" plywood, coated in epoxy, then painted.

Maybe cover the plywood w/ a sheet of laminate, then varnish over? Either way, keep the pressure treated wood insulated from any aluminum. It'll eat it over time.

Helm and deck look good though.

Good idea about the laminate. It's not that important to me, so I'll see how much that would cost. Otherwise I'll just go with the 3/4" pressure treated plywood.

Should I use the same thing for the motor mount block on the other side of the aluminum transom?

Last question - if I go to Home Depot and tell them I need "Epoxy resin to coat this plywood for waterproofing," will they know what that means?

Thanks for all your help,
Adam
 

BMOLCHANY

Petty Officer 1st Class
Joined
Jul 3, 2008
Messages
224
Re: Quick Question - Type of Wood For Transom

Try particleboard and let me know how it comes out. Just kidding I would go with a hardwood oak, maple or ash.
 

SS MAYFLOAT

Admiral
Joined
May 17, 2001
Messages
6,372
Re: Quick Question - Type of Wood For Transom

No bigger of an area than your doing, why not going with solid wood? The wood you have finished looks great. If your transom is going to be exposed and be seen, it would only be fitting to put in solid wood.

There is several ways that you can cover that area in solid. Lowes and Home Depot both have prefinished table tops(cut it to size). Or get some boards of your choice. You can fasten the boards together with biscuits/dowels, or run cross planking with glue and screws.

Treated ply will not give you a good looking finish like the rest of the boat. JMHO
 

adamkosecki

Seaman Apprentice
Joined
Jul 1, 2004
Messages
37
Re: Quick Question - Type of Wood For Transom

No bigger of an area than your doing, why not going with solid wood? The wood you have finished looks great. If your transom is going to be exposed and be seen, it would only be fitting to put in solid wood.

There is several ways that you can cover that area in solid. Lowes and Home Depot both have prefinished table tops(cut it to size). Or get some boards of your choice. You can fasten the boards together with biscuits/dowels, or run cross planking with glue and screws.

Treated ply will not give you a good looking finish like the rest of the boat. JMHO

I wasn't going to do anything but paint it if I used plywood. I thought about using maple or oak as I could finish it and it would be very strong, but it would also be very expensive. Some of these decisions will be made when I see the prices at Home Depot.
 

Coors

Captain
Joined
Dec 8, 2006
Messages
3,367
Re: Quick Question - Type of Wood For Transom

I read this in another thread and did not plan on doing that.



I understand that, that's why I'm talking to you and asking for help. I did my search research before posting. Some of the questions I'm asking are more specific to my boat than the general results I have already found.



Good idea about the laminate. It's not that important to me, so I'll see how much that would cost. Otherwise I'll just go with the 3/4" pressure treated plywood.

Should I use the same thing for the motor mount block on the other side of the aluminum transom?

Last question - if I go to Home Depot and tell them I need "Epoxy resin to coat this plywood for waterproofing," will they know what that means?

Thanks for all your help,
Adam

Do you have 2 months to dry the PT?
 

77mutiny

Seaman Apprentice
Joined
Apr 21, 2008
Messages
35
Re: Quick Question - Type of Wood For Transom

i've got to replace my transom as well and it originally was 3/4''. i went to home depot here in mississippi and they've got some nice oak and birch plywood for between 30 to 50$ for a 4x8. anyone know how well those woods hold up?

they also have 4x8 pt ply for around 50 to 60
 

SS MAYFLOAT

Admiral
Joined
May 17, 2001
Messages
6,372
Re: Quick Question - Type of Wood For Transom

i've got to replace my transom as well and it originally was 3/4''. i went to home depot here in mississippi and they've got some nice oak and birch plywood for between 30 to 50$ for a 4x8. anyone know how well those woods hold up?

they also have 4x8 pt ply for around 50 to 60

I've tried the oak ply around the rear deck of the cabin of mine. The first season it looks great. But by the end of the season it started looking crappy. Then by spring (while covered during winter) it started to delaminate. Those types of ply are designed for interior use. The edges to the end grain are just to hard to get sealed up to keep the moisture out. Someone may have different results by a different method of sealing, but interior stuff is not designed for the harsh elements that outdoor weather throws at it. Also the veneer on those sheets is very thin. It is very easy to sand threw if trying to sand out a defect.
 

SS MAYFLOAT

Admiral
Joined
May 17, 2001
Messages
6,372
Re: Quick Question - Type of Wood For Transom

Thats as if you want paint to stay on it. Be careful when its drying as it has a tendency to warp.
 

Joe_the_boatman

Chief Petty Officer
Joined
Apr 14, 2005
Messages
482
Re: Quick Question - Type of Wood For Transom

Last question - if I go to Home Depot and tell them I need "Epoxy resin to coat this plywood for waterproofing," will they know what that means?

Thanks for all your help,
Adam

I doubt it. They sell poly resin (Bondo or Elmer's brand? I forgot), which is similar to epoxy - it's also used to lay up fiberglass. Epoxy is superior in many ways, and oz for oz, the stuff at Home Depot is as much as mail order epoxy.

Still, many people use poly resin and are happy with it. And it's convenient to go down the street and pick it up.

PT=Pressure Treated, usually referring to plywood here.

And yes, it needs to dry for a good while. The "MCQ" (micronized) PT that Home Depot carries (as opposed to Lowe's) was much drier than any other PT I've dealt with.
 

Coors

Captain
Joined
Dec 8, 2006
Messages
3,367
Re: Quick Question - Type of Wood For Transom

Get some exterior ply (the glue is better).
Go to local discount boat supply store, and buy epoxy, like MAS, cheap.
Remember, a lot of epoxy needs to be covered from uv rays.
 
Top