Transom replacment

matridium

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Mar 12, 2005
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14
I have searched the forums for this topic and have found many posts however nothing that seems to apply to what I need to do is listed.<br />I have a 73 duracraft aluminum boat. I need to replace the transom beucase it has several rooten spots in it. I have figured out how to remove the transom however there is a bar that comes from the floor on an angle to the wood that seems to support the transom. IM not sure how to remove this part without having to remove the rivets. Also I need to know what is the best wood to use? I have access to 1" mahogeny plywood and 1" Oak plywood would either of these work? Should the trnasom be attached with rivets or Stainless bolts? Should I use a silicon sealent on the holes or somehting like JB weld? Also What is the best coating to protect the wood? would apoxy paint be a good choice? <br /><br />thank you <br />Michael Moore
 

swimmin' for shore

Chief Petty Officer
Joined
Oct 25, 2004
Messages
490
Re: Transom replacment

I can't answer all of this, but I'll answer what I can here. My aluminum boat would require you to remove the rivets if you want to remove the old transom and support bar. Your best bet on that is to take a picture of it and post here. Most people know more about those than I can help with. Depending on what size and number of holes you have, your best bet, honestly, is to take it to a welder and have them weld the holes closed. You don't lose the integrity of the aluminum that way. As for paint, do a search here for that. There are brand name suggestions that you can find, and the primers necessary to do it right. I hope that answers some of your questions, and hopefully someone will be able to answer the rest for you.<br />Oh, last thing. As far as wood goes, there are a ton of choices for that. Mahogany seems kind of expensive, but if you already have it, I can't see that it would be bad. Most people use marine grade or pressure treated plywood, and there are no end to the arguments that can invoke. Either way, you're going to want it as dry as possible, and then epoxied for water resistance. For permanant transom work, do a search online for seacast and look at the properties of that. It's expensive, but you'll only do it once. Good luck
 

Realgun

Commander
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Jul 31, 2003
Messages
2,484
Re: Transom replacment

It is easy to remove the rivits just drill them out. I would suggest you do this anyway. Oak or Mohgany plywood should be fine however is it Marine grade? I would always use marine grade for transom and stringers do to the plys not having voids. <br /><br />Coat all edges of wood with epoxy not poly. If you apply 2 coats you will get maximium protection. If you do the two coats in less than 48 hours you will not have to sand between coats.<br /><br />You will need to paint the epoxy to protect it from U.V. light. It will become brittle and turn yellow if not covered.
 

Bondo

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Apr 17, 2002
Messages
71,137
Re: Transom replacment

I have access to 1" mahogeny plywood and 1" Oak plywood would either of these work?
I'd use P/T plywood,... It'll Never Rot......Oak is a rather Fast Rotting wood...Mahogney is for Decks or Galley/Cabin walls isn't it...?? <br />
Should the trnasom be attached with rivets or Stainless bolts?
I used SSteel Screws,+ nuts.....<br />
Should I use a silicon sealent on the holes or somehting like JB weld?
Silicone has No Place below the waterline.... JB Weld is Too Hard, with No Flex when dry...<br />Use 5200.........And,.. Use as many of the exsisting holes as possible, for all the New Screws....
 

Realgun

Commander
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Jul 31, 2003
Messages
2,484
Re: Transom replacment

Don't crank down to hard on the S/S bolts they will strip out rather easily.
 

Beck

Petty Officer 2nd Class
Joined
Feb 24, 2004
Messages
165
Re: Transom replacment

Matridium, here's my .02 <br /><br />I have changed the transom in 2 alluminum boats. I had to remove the floor to transom brace, drilled out the all. rivets going thru the floor and unbolted the ones thru the transom. I would think pressure treated would be the best, but I used ext. plywood that I had already. The transom normally doesn't get wet and if it does it doesn't stay wet. As I remember I had to laminate 2 pieces as I think the old transom was a odd size like 1-1/4 thick. I had 3/4 and 1/2 and gluded them together and screwed them with s/s screws. I then primed them and top coated them concentrating on the edges. After reinserting on boat s/s bolts thru all existing holes with marine sealent 5200, it holds very well and stays plyable. I then used s/s carrage boats thru the bottom with 5200 coated on the heads. I secured them with lock washer, nut and then a nylon lock nut. All s/s of course. I say that because I learned the hard way and used galv. nuts once and electrolises started, had to redo several. I never ever had a problem with s/s.<br /><br />I have also replaced leaking rivets with s/s carrage bolts coating the heads with 5200.<br /><br />Hope this helps,<br />Beck
 

matridium

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Joined
Mar 12, 2005
Messages
14
Re: Transom replacment

I just found at my local ACE hardware they sell rivets that are for Marine Boat repair they sell two sizes 1/4 inch grip by 3/16 hole and 1/8 grip by 3/16 hole. They are close end so they will not leak, They are aluminum with steel coated mandrels. Pack of 10 is $2.99 in my town. I might use these to replace the existing rivites. Also noticed at a local hardware (MOM POP) they had very long S/S Sex bolts that can be use to put the transum back on, they range form 1/4" to 3" long and with variouse size heads. Also one more thing, I talked with a good friend of mine who builds Aquariums for a living. I asked him if he uses 5200 for saltwater aquariums? He said he has when Aquarium sealent was not available. But he also said 5200 and Aquarium sealent are one in the same. they both can be submerged under water for eternity, both can be in fresh or salt water, and both are very flexable and have high stregth ratings, He did say Aquarium sealent maybe be a little higher qulity beucase it does not react with ozone, or UV light, he was not too sure about 5200. the only difference is a tube of 5200 is about $5.99 - $6.99, and the aqurium sealten is about $3.99 - $4.99 a tube.
 

matridium

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Joined
Mar 12, 2005
Messages
14
Re: Transom replacment

By the way Beck thank you for the details. I think I will try what you say in regards to the transum. My be use the ritets in place of the s/s bolts.
 
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