Easy transom question

bonz_d

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As some may have seen I just acquired a 14' aluminum row boat that I believe is a mid to late 50s Crestliner. No registration and no HID so no one has a clue what this really is.

Anyways all the transom wood is already gone and from pictures I've seen it appears that a 3/4" solid pc of wood was used. There is a bracket riveted onto each side that the wood was fastened thru. Again this space is only 3/4". My thought and question is this. Which would be better just using one pc of 3/4" ply or using 3 layers of 1/4" ply. Which would be stronger?
 

Tnstratofam

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I would think the 3/4 would be stronger, but if the 1/4 pieces are glued together good enough then it should be equal in strength.
 

JASinIL2006

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If you can find a decent grade of 3/4" plywood (and remember, the actual thickness will probably be different from the nominal thickness) of something like Arauco plywood, you will probably get just as many (if not more) plies than if you try to glue up your own. If you buy a standard old piece of CDX or something like that, you'll get fewer plies, but a quality piece of plywood will have more. Also, I don't think you'll get quite as good bonding sealing 1/4" plywood sheets as the factory can get.

Marine ply would be OK, too, but it's quite a bit more pricey, and Arauco shares the best qualities of marine (lots of plies, few voids) without the cost.
 

bonz_d

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Our Menards carries both, marine and Arauco in 1/4", 1/2" and 3/4". They also have 1X12 Popular in a length that will work but I'm afraid that may warp.

Also from the pictures I've seen in the brochures there is also a board on the outside of the transom that fits under the corner end caps.
 

JASinIL2006

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I can't say anything about the transom in your boat, but I can tell you that the Arauco plywood is nifty stuff. I've started using it in many non-boating projects because it works so well.
 

bonz_d

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That is what I plan on using. The veneers look good and clean than it has more plies than the regular stuff and about 1/2 the price of marine.. Sad part is having to buy a whole sheet when I only need a 12x54" board. Then from what I can figure out the exterior pc needs to be 1/2". Going to be a lot of leftovers.
 

64osby

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Leftovers for the next project or added improvements to that boat.:joyous:

Thought you were redoing the storage compartments.
 

bonz_d

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I am. This is a second boat. Something to fish in while the Alumacraft is under renovation. Nothing fancy about this one but the old 9.5hp Johnson I've owner for many years should push it nicely.

So far only 2 responses on the plywood! Interesting.
 

gm280

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If you have the capabilities and seriously don't mind the extra work. I can see three pieces of 1/4" exterior plywood covered in polyester resin and then CSM on both sides. Then PBed the three pieces together with lots and lots of clamps, would be far superior then any this else, and 100% weatherproof as well. But that is just another option...
 

bonz_d

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Well I was going to go pick up plywood today for this but something else has come up, an outboard repair for a friend, so hopefully tomorrow.

This is an old, old tin can so I'm not going to sink a lot of money into it to make it look pretty also because this one might find it's self on the river bumbin a lot of stumps quite often. But here is a link to the other thread I have which has a few pictures of it. http://forums.iboats.com/forum/gene...gine-topics/9916031-14-row-boar-id-crestliner
This will also show the transom and what I'll be working with. Either way whether I use a single pc of 3/4" or multi layers of 1/4" I will most likely just treat it first with a wood sealer and then 5 or 6 coats of spar varnish even if that means having to recoat the varnish every couple years. After all it's not a large area so maintaining it is not a big issue.
 

dozerII

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Looking for a very strong stable ply you can't get much better than 13-15 ply Baltic Birch
 

Woodonglass

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Your thoughts on either a single pc of 3/4" or 3pcs.of laminated 1/4"

Depends on the 1/4" Ply. I've seen some pretty good 4ply Luan @ Home Depot that someday I'm gunna build a 12' boat out of when I retire. I figure if you use small modified WOG clamps and some 3/4" plywood backers you could coat that Luan with some thin coats of TB III and get a good enuf clamp on it to ensure a good bond and end up with a 3/4" piece of 12ply plywood. Would it be as good as the 7ply Arauco...??? Well that's for sure up for debate. If you laminated it with Epoxy it would be a lot stronger but a heck of a lot more Pricey!!!! For this little ole' boat Not sure it's really worth all the High Fangled Engineering!!!!:eek::D Truth be known Ifn' it were me and my boat, for a 12" x 54" transom board that was gunna be toting a 10horse motor...I'd prolly be shopping for the best straight grained Rift Sawn, Knot Free Douglas Fir 2x12 I could find and go with that. If it's Rift Sawn it won't warp and if you use the Old Timers on it, Your Grandkids Kids will be using it!!! AND you can plane it down to any thickness you want for the outside piece too!!!! A 10' 2x12 runs about $12 bucks here in Okie Land.
 
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bonz_d

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Leftovers for the next project or added improvements to that boat.:joyous:

Thought you were redoing the storage compartments.

Well I think I almost settled it. The lid panels on the other boat are 3/4" ply so now being there will be leftovers I need to decide on whether to buy the marine because I think it will take a stain finish better do I go with the Arauco and see if it will stain nicely.
 

64osby

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The Arauco I've seen at Menards has been very clean, doesn't have much grain pattern in it.
 

bonz_d

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Just finished measuring everything and I can cut all the pcs. for both boats from one sheet of 3/4", So off to Menards I go in the morning.

Again it's great to have a place like this where one can think out loud and have input from all the combined knowledge you folks provide.
 

gm280

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First of all YOU have to make any and all decisions after reading everybody else's opinions. And that is how it should be as well. One workable sheet of 3/4" would certainly be my route but that also would depend on the boat and my plans on its usage as well. You can make anything overbuilt or underbuilt. So you have to satisfy your wants and move on. But I do like all the different opinions and weigh each on their ideas to how it would work on my situation. I know whatever you decide, it will come out great... :thumb:
 
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