Wood transom

I am finally getting back to rebuilding my little boat. After a lot of thought I have decided to rebuild the transom using wood rather than the composites like Seacast or Nidabond. For one, I think wood is lighter and there is just something about working with wood that is more satisfying. The other is expense in that I can't see putting the cost of composite material into this. Anyway, as usual, I have questions.

I understand the benefits of marine plywood, however has anyone (sure you have) considered Oak or maybe Birch? Home Depot carries it, but I don't know the quality of it although is looks good. Regardless of the final product, I have a question about bedding the unit. I was thinking, before laying the transom into place, and after sealing/glassing/preparing, apply a bedding of PB along the bottom and sides and then tab. Logic tells me this should secure the edges and eliminate air space. I understand PB is made by combining cabosil and perhaps wood flour. On the other hand, cabosil is nasty stuff to be around your respiratory tract (yes, i use a mask). With that I was thinking of an alternative using a mixture of epoxy and only saw dust or sanding dust. It seems to me, since the transom is wood, a bedding of epoxy/saw dust or sanding dust or wood flour would follow suit. Then again, maybe that's just me.

Thoughts?




Thanks in advance.
Steve

Re: Wood transom

One thing to remember on your plywood is you want to have waterproof glue. Lots of guys have had excellent results with Auruco ply. I'm pretty sure it's cheaper than oak and would be comparable to birch.

Re: Wood transom

howdy idont........

a lot of us have been using the arauco plywood, including myself with great results. they have it at Lowes for around 33.00 for a 3/4" sheet and 29.00 for a 1/2" sheet or at least all the Lowes around me. if you are going to go with epoxy then wood flour is the preferred thickener. You will not have any problems with using Poly resing for your transom either and the cost is a lot less than the epoxy. i get 5 gallons of poly for 100.00 and a 2 gal kit of epoxy from us composites was around 112.00 i believe.

from my limited experience with this part of the job, completed mine at the end of last year, you want to "glue" your transom to the skin using csm or PB screeted between the skin and transom. once that is in and if you can work around your clamps or wait until they are off, then PB and fillet the edges then tab the transom in.


for some good reading about this there are several threads you can check out.

the infamous oops! hull extension
http://forums.iboats.com/showthread.php?t=234392

friscoboater
http://forums.iboats.com/showthread.php?t=454460&highlight=friscoboater

man vs. boat
http://forums.iboats.com/showthread.php?t=513763

and a ton of others out there as well.

Good luck..... I am sure others will be along shortly to lend a hand as well. will stay tuned in and offer what i can........

Re: Wood transom

Check out the link in my signature, for drawings and info for how to install your Transom, Deck and Stringers. Absolutely to NOT use the Oak or birch plywood. It is rated for Interior use only. You must use, at the very least, exterior grade plywood. The Arauco plywood is 7 ply, practically no voids and 100% waterproof glue. Good stuff. Are you truly using Epoxy or Polyester resin. If poly then the wood flour is not a good idea IMHO. Cabosil and Chopped milled fibers is a much better choice.

Re: Wood transom

Thanks for the heads up on the Oak/Birch! Looks like Arauco is the way to go. I am using epoxy resin and I was also considering the addition of some chopped fibers. Coincidentally, I was watching friscoboater's youtubes regarding his rebuild and he was preparing his transom using epoxy/cab/fiber. Good stuff and I recommend the video to any of you not having done this stuff before.

Thanks for all the suggestions!!

Re: Wood transom

I think friscoboater used all poly on his rebuild.

Re: Wood transom

boatnut74 said:

I think friscoboater used all poly on his rebuild.

Click to expand...

I believe you are correct and I don't believe he used wood flour, but he did use cabosil and filler. It was late at night when I watched it...one of those where sleep does not come easy.

Re: Wood transom

i have a few minor questions if ya don't mind?

first....your choice of materials seems to be health related.
If so ...why the epoxy?...Epoxy Is far more of a health risk than cabosil, especially where the respiratory tract is concerned.

(I don't want to start an argument here...just wondering why....that's all, its your boat bud.....you can use what ever you want on it ! )

as fas as the choice of wood....the ply you have selected is just fine and preferred...but remember.....even Interior grade, wrapped in glass will last 10 years. (However, I would not suggest to use it).

as for your procedure to install the transom.....may I suggest a little more reading before the install.

It sounds like you are good on the basics....but I think you are a little vague on the specifics.

we are all here to help.....and want to.....
dont be afraid to ask questions here....we want your build to be a very successful one.

cheers
oops

Re: Wood transom

no argument here oops! nor offense taken. i am learning as i go along. good question however regarding the epoxy. point taken. overall this rebuild stuff is not rocket science and for the most part, one just needs to follow the instructions and advice from the folks here. there is some really great stuff to learn. i grew up on the water and around boats, working with my hands in wood, concrete, building/remodeling houses, computers, antique cars (street rods), and other things so this stuff follows suit and if there are pictures and instructions it's not so bad.

i ask a lot of questions (and ponder) about everything.

Re: Wood transom

Bow deck

How strong is just fiberglass with epoxy applied? I know is hard as rock and impermeable, but what kind of weight (compared to thickness) will it support without a plywood core? The reason I ask is that cutting out the bow deck area I noted their was no support under the original fiberglass deck and just a quarter inch layer side to side. You can see it in the photo. I was thinking, in order to keep the area beneath open for storage, replace the deck with a build up of a quarter to half of glass/epoxy an not use wood cross members. Or would you suggest using quarter inch plywood, glassed heavy/epoxy, or... I like to experiment, but this stuff get expensive and the experts are here with all the "been there, done that" advice.

Thanks in advance!!

Steve

Re: Wood transom

I was thinking overnight about a solution and my thought is 1/4 inch plywood covered with 1/4 inch glass/epoxy with a center support beneath should work fine. We're only talking about a 4 foot span so I can't imagine it flexing.

Re: Wood transom

hello? anyone?

cricket
cricket
cricket

Re: Wood transom

Do you realize how many layers of glass and resin are required to obtain 1/4" thickness of glass? Very expensive and unless you know what you are doing the heat from the laminations can make it go bad very quickly. You should prolly stay with 3/8" ply and a couple of layers of 17 oz Biax. But...I would recommend some kind of support. You can cut carboard tubes in half and laminate over them. The cloth and the glass is what gives it the strength.

http://forums.iboats.com/showthread.php?t=364284

Check out post#18

Re: Wood transom

Thanks...great thread. That guy should compile all the info he posted and write a book on restoration.

The information was exactly what I was looking for...no need to reinvent the wheel.