Aluminium Transom repair, anybody done it?

oceanhorse

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May 19, 2009
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Have a StarCraft chieftain 18 foot and like so many others the transom is a little soft and Flexi, a fabricator offered to try and repair with aluminum so I was wondering if anybody else has had success with this? none of the marine repair companies around will repair her either! So this guy is my only option right now even though I'd like to keep her factory.
Any advice is appreciated, information and experience also. Tight lines guys from Vancouver island BC Canada
 

StarTed

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Jul 14, 2015
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It sounds like your Starcraft transom wood is rotten. Replace it and check the aluminum for pitting. Fill the pits with JB Weld and go from there.

I put a second skin over my Star Dust on the outside after doing the other work first. Looks and works great.

Have fun and good luck.
 

oceanhorse

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May 19, 2009
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Thanks guys, if I had the time and space to replace her myself I would; unfortunately I do not, so I'm going to hire it out; but none of the 8 marine yards want this job! Anyway that's my dilemma, only guy that's offered is a fabricator friend and I can't see the transom plywood being replaced with aluminum so was just looking for others solutions. Soaked on the wet coast
 

Scott Danforth

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tell your fabricator friend to do it the way you want it done (the right way) if he wants the work.
 

Watermann

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The original transom wood from the factory merely had a single coat white wash on it. New wood if sealed properly will last more than a lifetime if the boat is cared for and not let go to the elements.

If your Chief an IO or OB?
 

bob johnson

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I wouldn't dismiss the fabricator...... the ONLY reason to put wood back into an old starcraft is because its cheaper than the better fixes.... like all aluminum transom or a composite core board..... they will never rot again...... get a quote from your fabricator and ask what he plans to do EXACTLY...... to have the same or greater transom strength as the wood insert......boat owners are diverse...some stracraft transoms could last 50 years, others wont last 5 years..... details... the devil is in the details...... but a composite or all aluminum transom will last at least 50 years or more.....they will probably outlast the hull skin!
 

Candutch

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Like others have previously mentioned it sounds like the transom wood is rotten. Unless the fabricator is going to replace the plywood with another structurally sound material the repair will fail. There is no way putting an aluminum skin on the outside of the transom is going to be structurally sound. On my rebuild I, like most others, I replaced the 1 1/2" thick plywood transom sealed with spar varnish. I also skinned the outside of the transom with 3/16" aluminum back buttered with 5200 marine adhesive. The aluminum skin may have been overkill in my application but I guarantee if that is all I did, and I did not replace the wood, the motor would have fallen off while I was bouncing it down the logging roads.

So, unless your getting something to replace the structural component of the plywood like Bob mentioned, an aluminum transom or Core board etc, a skin of aluminum up to 1/4" won't cut it IMHO.
 

oceanhorse

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Well Gentlemen, first I appreciate all your experience and advice very much, you inspired me to get it done today. I didn't hear from the yard again since I called last week, I just drove right down there and asked the owner politely clear the way to my boat I'm taking it home, he was surprised said he found a fella to do it but no he has t a quote. I thanked him and hooked her up. My good karma came around as a local Starcraft owner older man, we spoke a few months ago, he offered to help me remove the old 850 merc. Two hours later she was off. I'm gonna take care of that fella and hopefully get a picture of his 21' because he's done some right nice fabricated aluminum on his. More pics of mine to follow its dark and I'm taking it to a boatbuilder tomorrow whom I hope is the real deal. I've my pressure treated plywood by the fire place drying. I'm planning on repowering with a clean '95 85hp Yamaha next. Really excited now. Can any of you fellas tell me if I can get two transom templates from on sheet of 3/4 ply??? Somebody must have done it. Otherwise I'll have to pick up another sheet enroute tomorrow. And I have some good exterior paint to slather on her to protect her befor the. We transom is installed. Any advice is appreciated th aka again for the great rebuild&repair reports.
 

GA_Boater

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Throw away the pressure treated plywood or save it for another project. PT eats aluminum for breakfast, lunch and dinner and in between snacks. PT wood should not be used in aluminum boats.

You need two sheets of ply for the transom. The boat is wider than 4 ft. so the transom is cut out along the 8 ft. length requiring 2 sheets.
 

baldwibr

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Agreed. Pressure treated wood in aluminum boats is not a good idea. Just get marine grade plywood or you can even use exterior grade plywood. Don't use interior or cabinet grade plywood since they normally have a water-soluble glue.
 

Watermann

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Yeah no CA treated plywood, the copper will destroy your Chief's transom AL in short order. AC exterior grade ply is the best option for price and strength. Then I like to seal mine up with spar, oil based primer and 2 coats of oil paint after drilling all the through holes.5200 to seal the deal on all the screws and bolts.

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oceanhorse

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So I have a sheet of exterior grade plywood, it has a treated hue to it, I'm not sure if it has copper in it or not. I assumed that exterior grade plywood was pressure treated. Was left over from my untility trailer resheet. I'll source some marine grade hopefully it's not far away. Oil based primer and paint or spar varnish-check
 

Watermann

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Exterior grade just means that the glue used to laminate the sheets is waterproof, same as marine grade which has 2 A sides and few if any small voids. It's also twice the price as say ACX fir ply which has an A side, C side and is eXterior.
 

fishrdan

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So I have a sheet of exterior grade plywood, it has a treated hue to it

Is it green colored or yellow/orange tinted?

ACQ treated is big box cheap "green" treated plywood that will eat an aluminum boat, don't use it. Easy to find and cheap.

CCA treated plywood has a yellow/orange tint and is safe for aluminum, aluminum boat manufacturers use it. Hard to find and expensive.

Plain untreated exterior plywood will work, but you need to seal it like others posted, so it doesn't rot. There are many types of "marine grade" plywood, some treated like pontoon decking. Commonly what you'll find at lumber yards is marine grade douglas fir plywood, which is high quality plywood, but untreated, so it will still rot unless sealed.
 

crankbait cowboy

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IMG_0058.JPGIMG_0066.JPGIMG_0068.JPG 2 pieces of 3/4 marine grade glued with wood glue ( use trowel to cover well) clamped and left to bond, then drop in, drill all holes (STRAIGHT THRU IS IMPORTANT) take out transom and coat with 3 coats epoxy or spar, getting all edges and voids extra, clean up aluminum and fill pitting with jb weld and sanding if you have pitting, and then drop transom back in bolting with ss bolts and lathered in 5200. is the way i went, following advice from many on this forum, and worked out real well
 

oceanhorse

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Thanks waterman, dan & cowboy, for pictures and knowledge of the repair, the proper way. I'll contact the shipbuilder fella see if i can visit for a minute check out the progress on Monday. Ill share these pics and techniques over a couple beer. Heres some pics, i know im no photographer
 

oceanhorse

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oceanhorse

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May 19, 2009
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2 pieces of 3/4 marine grade glued with wood glue ( use trowel to cover well) clamped and left to bond, then drop in, drill all holes (STRAIGHT THRU IS IMPORTANT) take out transom and coat with 3 coats epoxy or spar, getting all edges and voids extra, clean up aluminum and fill pitting with jb weld
Did you bolt thru the transom all the way around the perimiter(below the waterline aswell?) Or just above the water line? I was planning on new hardware(screws)in the C channel inboard, and bolting thru the 12"x24" outboard plywood transom support piece of course glassed and sealed with sikkaflex. The thru hull drains shouldnt be too hard to find, strong shouldered towing/tiedown eyes, its an 85hp Yammy
 

GA_Boater

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