# Gregor 12 - Transom Repair/Replacement



## AlexB (Jun 8, 2016)

What's up, guys?

I'm getting ready to replace the transom wood in my 12 foot Gregor (1977), and I figured I'd start this thread to document the process and hopefully get some good advice along the way. 

As you may know, Gregor boats have two triangle-shaped transom braces that are welded to the floor and bolted through the transom. The transom wood is sandwiched between the braces and the aluminum hull itself, and there's an aluminum "cap" that wraps over the top of the transom wood. There is no way to replace the wood without either cutting the transom braces or severely bending the aluminum "cap". 

After speaking with some folks at the Gregor factory, I came up with a plan. I'll slice each transom brace off with a horizontal cut ~3 inches above the floor. After sliding the new wood into place, I'll repair the two braces by "sandwiching" them with plates of 0.125" 6061 T6 aluminum and secure with SS hardware. 

That brings up my first question... 

What do you suppose is the best tool to get a nice clean cut through the thin aluminum transom braces and 0.125" thick aluminum sheet? I have at my disposal (1) jig saw, (2) angle grinder, (3) circular saw, (3) hack saw, and (4) oscillating multi tool. Whichever tool I decide to use, I'll need to buy a new blade for it, so I welcome your suggestions there, too.

Thanks in advance, and stay tuned for some pictures. 

Cheers,

~Alex


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## lckstckn2smknbrls (Jun 8, 2016)

I would either bend the top cap up (which is what I did on my boat) or cut off the top cap and fabricate a new one.
Can you post some pictures?


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## DaleH (Jun 8, 2016)

Most likely that aluminum hull is 5052 alloy, so that's what I'd use. 

I bought a sheet 5052 H3 full sheet and have some left over, so depending on the size needed I could cut some and send you shapes needed - just pay fair price plus shipping.

A sawz-all with fine blade cuts through aluminum like butter, but can be tough for an accurate cut. I cut my 5052 with a new fine blade in a jigsaw and it was super.

I will add, for detail cuts, even through fiberglass, where I really needed to be "on the line" to make accurate cuts, say like on a helm dash or such, I always would buy a new (never would use a used blade ...) 'laminate' blade that cuts on the down-stroke. This gives the tool more control and leaves a extremely clean cut on the visible surface.

Oh, and insulate the SS hardware from the aluminum, even if only heatshrink on the bolts and nylon washers under the bolt hears and nylok washers/nuts.


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## AlexB (Jun 8, 2016)

Huh. How did you finagle the new wood around the two welded in corner gussets? My transom wood is the same width as the transom, so I don't see how I could lift it past the corner gussets.


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## AlexB (Jun 8, 2016)

DaleH said:


> Most likely that aluminum hull is 5052 alloy, so that's what I'd use.
> 
> I bought a sheet 5052 H3 full sheet and have some left over, so depending on the size needed I could cut some and send you shapes needed - just pay fair price plus shipping.
> 
> ...



Thanks for the advice. Are 6061 T6 and 5052 alloys dissimilar enough to cause a problem? Or was there another reason for your suggestion? I have already bought the 6061 T6, but if the 5052 is truly a better choice I'm sure I can find a use for the stuff I ordered.

I'm still hesitant to try bending or cutting the cap. I'm confident I can make a clean repair using straight cuts and bolts, but I'm not sure I'd be happy with the results of going at my boat with a rubber mallet.

Lock Stock - You mentioned the option of fabricating a new cap. How might I do this? I just have basic hand tools and I don't have much experience working with aluminum.


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## DaleH (Jun 8, 2016)

Hull makers use 5052 sheet over 6061 as it bends easier and is a work-hardened material, where the other is thermally hardened. In metals, their is toughness (ductile) and strength. Too strong and it's brittle. Looking at the formed features on most tin boats and you can easily see why a tough but bendable aluminum is used. 

Sounds like you're just using reinforcing plates to mate the cut areas ... so I'd just use what you have.

Have fun! Please let us know how you make out ...


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## AlexB (Jun 8, 2016)

Thanks, Dale.

You're right. The aluminum shouldn't see any bending stress in the situation, and frankly I think it will be be way overbuilt with two 1/8" sheets to repair the thin (1/16"?) piece I'll be cutting. To make the repair even more burly, I also ordered some 1/8" thick 1.5x2" aluminum angle that will wrap around around the 90* bend of the transom brace (the bend that gives a flat surface for bolting to the transom). The angle will be secured with more SS bolts and should restore all of the original rigidity/stiffness of the brace.


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## lckstckn2smknbrls (Jun 8, 2016)

AlexB said:


> Huh. How did you finagle the new wood around the two welded in corner gussets? My transom wood is the same width as the transom, so I don't see how I could lift it past the corner gussets.


I cut through the welds with a grinder, then had them welded back on.


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## lckstckn2smknbrls (Jun 8, 2016)

I will be making a new transom cap for the StarCraft Falcon I'm working on. I plan on using two pieces of 3/4" aluminum angle 1/16" thick and one piece of flat stock aluminum 1-1/2" wide 1/16" thick. 
The transom is 1-1/2" thick so the 2 pieces of angle will cover it. I will anneal the aluminum so it is bendable. When I have the angle shaped I will rivet the flat stock over the top of the angle.


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## AlexB (Jun 8, 2016)

lckstckn2smknbrls said:


> AlexB said:
> 
> 
> > Huh. How did you finagle the new wood around the two welded in corner gussets? My transom wood is the same width as the transom, so I don't see how I could lift it past the corner gussets.
> ...



Ah. I see. I'm really trying to avoid the need for welding. I still don't have a trailer (or a motor...) for the boat, so it would be tough to transport it to a welding shop. With the cut+bolt method, I should be able to get the transom fixed up quickly so I'm ready to hit the lake as soon as I score a trailer and motor. And, if the transom wood ever needs to be swapped out again (boat stores outside), I can just unbolt it.


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## AlexB (Jun 8, 2016)

lckstckn2smknbrls said:


> I will be making a new transom cap for the StarCraft Falcon I'm working on. I plan on using two pieces of 3/4" aluminum angle 1/16" thick and one piece of flat stock aluminum 1-1/2" wide 1/16" thick.
> The transom is 1-1/2" thick so the 2 pieces of angle will cover it. I will anneal the aluminum so it is bendable. When I have the angle shaped I will rivet the flat stock over the top of the angle.



Thanks for the reply. That sounds like it'll come out real nice, but also sounds quite time consuming. Fun, too, but With my limited free time I prefer to spend it fishing.


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## lckstckn2smknbrls (Jun 8, 2016)

AlexB said:


> lckstckn2smknbrls said:
> 
> 
> > I will be making a new transom cap for the StarCraft Falcon I'm working on. I plan on using two pieces of 3/4" aluminum angle 1/16" thick and one piece of flat stock aluminum 1-1/2" wide 1/16" thick.
> ...


There is another Gregor build in the conversion and mod forum that has some pictures. It shows the transom as being flat across the top, if your boat is the same there would be no need to anneal and bend the aluminum angle. Being flat would make fabricating a new transom cap very easy.


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## AlexB (Jun 9, 2016)

The transom is flat across the back, but I'd still have to grind off and re-weld the corner gussets, which I would very much like to avoid (I hate paying other people to work on my things).

Here's my plan for transom wood... Gregor told me the original transom was constructed of three *actual* 1/2" sheets of plywood glued together to create an *actual* 1-1/2" transom. Today's 1/2" plywood is 15/32", or 1/32" shy of 1/2". If I sandwich three of today's 1/2" sheets together, I'll be about 3/32" shy of 1-1/2". If I sandwich two 3/4" sheets together I'll be 2/32" shy. But, if I sandwich two 1/2" and one 5/8", I come out 1/32" OVER the desired 1-1/2" thickness, which should work great with a little light sanding. 

Here's my plan for the wood:

1)Trace the old transom board, and cut out the three new pieces using circular saw and jig saw as needed.

2)Wipe them clean and glue together with Tight Bond III (other suggestions?). I figure I'll place them on my basement floor and pile a few bags of cement on top to keep them flat and situated while the glue dries.

3)Touch up the edges with a sanding block, Surform, or whatever works.

4)Slide the wood into place, clamp it securely, and drill each hole.

5)Remove the wood and "overdrill" each hole with a ~1/2" bit.

6)Cover/seal each hole with tape on one side, fill each hole with Marine Tex epoxy, and allow to set.

7)remove the tape and clean up a little with a sanding block.

8 ) After a quick swipe with some fine sandpaper, thoroughly seal the transom wood with the "old timer" blend of boiled linseed oil, spar urethane, and mineral spirits until no more will soak into the wood. For applying the old timer blend, do you just keep applying it heavily in one sitting until it puddles then let it dry and call it good, or do you apply it in coats like you would with paint?

9)Possibly paint with some oil based paint? Is it necessary (or recommended) after applying the old timer blend?

10)Slide the wood back in place, clamp securely, re-drill holes through the cured epoxy, and reinstall new SS hardware. I'm still looking at different options for an insulating layer/substance between the SS and the aluminum. Duralac seems to be a decent choice, but I don't know about it's waterproofing capabilities. Any recommendations for a good bolt hole sealer/insulator that won't form a permanent bond in case transom ever needs work again?

I welcome any tips or suggestions. 

Thanks in advance,

~Alex


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## AlexB (Jun 9, 2016)

Here's a picture of the transom. Should I plan to replace the little piece of sheet metal that's screwed to the wood? I could see it protecting the wood, but it also adds four screw holes that water could possibly enter.

Do you guys bolt your outboards straight in contact with the transom wood, or add a little sheet metal? I'll be storing the boat in the yard with the motor removed, if that makes any difference.








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## AlexB (Jun 9, 2016)

This is (approximately) where I plan to cut the transom braces.





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## BigTerp (Jun 9, 2016)

A few suggestions from my experience replacing the transom in my 1648:

1. Rough cut your wood, glue and THEN cut to size. Much easier to cut the final piece to size than trying to cut 2 seperate pieces exactly the same size. This also allows you to screw around the perimeter to "clamp" the wood while drying without putting holes in your final piece. It doesn't have to be perfect (mine certainly wasn't) but you want to try and get it as close to the original as possible.

2. I'd suggest sealing the wood, once you have it glued and ready to go (titebond III is what i used), with some epoxy resin. I replaced my transom almost 4 years ago and it's as good as new. It does stay covered outside, but gets put through the ringer year round hunting and fishing. I'd imagine my transom will outlast me.

3. Do not drill your new transom holes from the old wood, use the actually transom as a template. What I did was had my wife hold the new wood up to the transom while I drilled the top 2 mounting holes. I then bolted them into place and then, using the existing holes in the hull itself, I drilled out the remainder of the holes. Everything then lined up really well. I did this after my second coat of epoxy. This allowed for the last coat of epoxy and the coats of urethane to seal up the holes a bit.

4. If you go the epoxy resin route, get some good spar urethane that is UV resistant to protect your transom from the sun.

5. Take a few pictures of the original transom and bracing before you remove it. I couldn't remember how a few pieces lined up but luckly I had taken pictures of the boat when I first brought her home. Was nice having that reference.


I didn't have to cut any bracing out to replace my transom. My knee braces were secured to the hull with solid rivets. But I did do a LOT of aluminum work putting in a floor, deck and hatches. I used an angle grinder with these blades from Home Depot for all of my aluminum cuts. The wheels are thinner than standard grinder wheels and cut quicker through aluminum, but they do wear out faster than standard blades. Worked great for me. https://www.homedepot.com/p/Diablo-4-1-2-in-x-0-040-in-x-7-8-in-Thin-Kerf-Metal-Cut-Off-Disc-DBD045040101F/202830995

Here is the start of the transom work in my build thread. Hope it helps.......https://forum.tinboats.net/viewtopic.php?f=83&t=26774&start=30


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## AlexB (Jun 9, 2016)

Great advice! Thank you!

I like the idea of gluing THEN cutting. Sounds like it'll work great.

I definitely plan to use the aluminum transom itself as a guide for drilling holes, pretty much exactly how you described. I also plan to use a drill bit guide to ensure all my holes are drilled at the proper 90* angle.

Regarding the epoxy resin seal... Are you suggesting the epoxy go on over the "old timer" seal, or instead of it? And how does the UV resistant spar varnish come into play if I'm dealing with epoxy?

Thanks again. I'll be sure to check out your thread.


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## AlexB (Jun 9, 2016)

Good point about taking photos along the way. It's always nice to have a reference to look back on

For cutting and repairing the transom braces, I plan to clamp the new aluminum sheet and aluminum angle in place and drill holes through the whole "sandwich" BEFORE I actually cut the braces. Then I'll remove the new materials and make the cuts. That way I won't have to worry about factoring in the blade kerf when I put it all back together.


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## BigTerp (Jun 9, 2016)

AlexB said:


> Great advice! Thank you!
> 
> I like the idea of gluing THEN cutting. Sounds like it'll work great.
> 
> ...



Not a problem.

Yeah, the gluing and then cutting is the way to go.

I have no idea how well that seal mixture you're planning on using will last or how protective it will be on a wood transom. I do know that exopy resin is great at sealing and protecting the wood. Unless someone else has experience with that "old timer" seal with good results, I'd go with the epoxy resin. Should last a VERY long time if done properly. The spar will go over top of the epoxy once it is cured. I think I used 2 coats of spar. It is only for UV protection since the epoxy resin does not provide any on its own.


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## lckstckn2smknbrls (Jun 9, 2016)

I glued the layers of plywood together before I cut the transom to it's final shape.
I applied the old timers all at once on one side and the edges once it would not soak up any more. I then flipped it over and applied it that side. I then stood the transom on 2 pieces of scrap 1"x2" and left to dry. 
3m 4200 is a good choice if you think the bolts might have to be removed in the future.
Wood sealed with old times will last for decades.


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## lckstckn2smknbrls (Jun 9, 2016)

Once I had my transom cut to shape I installed it in the boat and marked all the holes on both sides on the wood. The bolts are 1/4". I drilled all of the holes half way thru the wood with a 5/16" bit the flipped the transom and drill the rest of the way with a 1/4" bit, then finish drilling the hole from the first side with the 5/16" bit. My thinking was the 1/4" bit would find the 5/16" hole and follow it. Of the 26 holes thru the transom only 2 where not perfectly in line. I had to open 2 of the holes in the braces a little.
I used a drill press.


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## AlexB (Jun 9, 2016)

Good stuff. Thanks again, guys!


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## AlexB (Jun 14, 2016)

Another quick question if you don't mind...

Should I plan to clamp the motor directly against the wood transom, or cover the wood with some sheet metal (like you see in the pic above). I don't know if that sheet metal was installed by Gregor or some previous owner.


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## lckstckn2smknbrls (Jun 14, 2016)

My 14' jon had an aluminum plate. When I replaced the transom wood I reinstalled the plate.


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## AlexB (Jun 14, 2016)

Thanks. Did you just screw it in place with a wood screw at each corner? Maybe seal behind/under it with some silicone or something?


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## lckstckn2smknbrls (Jun 14, 2016)

AlexB said:


> Thanks. Did you just screw it in place with a wood screw at each corner? Maybe seal behind/under it with some silicone or something?
> 
> 
> Sent from my iPhone using Tapatalk


I just screwed it to the wood. I may have used stainless steel screws I don't remember.


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## AlexB (Jun 14, 2016)

Thanks!


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## Joshyouwa (Jun 18, 2016)

I just replaced the transom on my gregor. I didn't want to cut the brackets or do any welding so I went with three pieces of ply and a sheet of aluminum. I forced the wood in and bent it until it shaped into place. Overall I replaced it and feel it is better than what I had on there. No cutting No welding. Just a rubber mallet and some force









Good luck on it.


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## AlexB (Jul 5, 2016)

All right! I made some good progress on my transom rebuild over the weekend! 

I cut the two triangle-shaped transom braces, and fabricated some aluminum plates to secure them back together. I also removed the old transom wood (wow was it sh*tty...) and laminated up a new one using ACX plywood and Titebond III glue (pics to come).

Before I reinstall the wood, I want to do a nice job patching all the extra holes (red circles in the attached photo) that have been drilled through the aluminum transom. Some holes are below the water line, and some are above. Some will be hidden under the transom wood, and others will be visible from inside the boat.

Here's how I plan to repair the holes. Please let me know what you think.

1) Remove all the old patching materials (JB Weld, I think? 5200 maybe?).

2) Lightly sand/scuff the aluminum surrounding each hole, then wipe clean with acetone.

3) Using JB Weld, glue small (approx 1" square or round) patches of ~1/32" aluminum sheet on the INSIDE of each hole to act as backing plates. Allow to set.

4) Apply JB Weld to each hole on the the outside, filling the void in the aluminum. Allow to set.

5) Sand each repair on the outside, leaving just a small circular spot of JB weld at each hole.

How does this sound? I'm leaning toward this ethos because I think it will give me a solid repair that doesn't stick out like a bolt/nut/glue patch would. Many of these repairs will be under the transom wood, so they can't stick out at all. 

Thoughts?








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## AlexB (Jul 6, 2016)

A couple pics of the new transom wood. It's 3 layers of 1/2" ACX (Aruoco brand) bonded together with Titebond III. As suggested, I rough cut the pieces, glued, screwed, piled with sacks of concrete while it cured/dried, then did the final cuts. This proved very helpful, since the outside edges pulled apart slightly as the glue cured. 

The board fits nice n' snug, so I wedged it in there and marked each bolt hole location. 6 holes for the transom braces, 4 holes for the transom mounted beach wheels, and 4 holes for the carrying handles. 

After drilling the holes (then "over drilling", filling with epoxy, and re-drilling), I'll treat the wood using the "old timer blend" of boiled linseed oil, mineral spirits, and spar urethane.










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## BigTerp (Jul 7, 2016)

Good work. Transom wood turned out very nice.

I'd stay away from JB weld, especially on your transom and below the water line. It doesn't flex and will eventually crack. I'd imagine the stress you get on your transom will be enough to crack it in short order. The best thing to do would be have those holes welded. If that's not an option, solid rivets with a bit of 5200 would be my next choice. With solid rivets you can get the shank/shaft pretty well close to flush with the inside of the aluminum so it wouldn't interfere with the transom wood. Problem though is if they ever need replaced you'd have to remove the transom wood to do so. FWIW my transom wood has a piece of aluminum on the bottom of it that's attached to the transom itself with solid rivets. I replaced them when I re did my transom 4 years ago and not a single issue with any of them. I also have my old transducer holes sealed with solid rivets, no problems there either. A third option would be to to use stainless nuts and bolts with a bit of 5200. For the holes that the transom wood would cover, you could drill through the wood and fasten the nuts/bolts just like all the others that are meant to hold your transom in place. I would think that would work out OK?


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## AlexB (Jul 7, 2016)

Thanks for the tips, BigTerp.

I think the rivet approach could work well for the holes below the transom wood, but I'm not sure about the ones behind it. The wood fits really snug, so I'm afraid anything sticking out of the aluminum behind the wood might cause the aluminum to deform when I cinch down the transom brace bolts, carry handle bolts, etc.

I might just drill out the wood and use SS bolts+5200 for a few extra holes, but there are quite a few... I think some are just going to need to be patched somehow.


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## AlexB (Jul 7, 2016)

BigTerp said:


> Good work. Transom wood turned out very nice.
> 
> I'd stay away from JB weld, especially on your transom and below the water line. It doesn't flex and will eventually crack. I'd imagine the stress you get on your transom will be enough to crack it in short order. The best thing to do would be have those holes welded. If that's not an option, solid rivets with a bit of 5200 would be my next choice. With solid rivets you can get the shank/shaft pretty well close to flush with the inside of the aluminum so it wouldn't interfere with the transom wood. Problem though is if they ever need replaced you'd have to remove the transom wood to do so. FWIW my transom wood has a piece of aluminum on the bottom of it that's attached to the transom itself with solid rivets. I replaced them when I re did my transom 4 years ago and not a single issue with any of them. I also have my old transducer holes sealed with solid rivets, no problems there either. A third option would be to to use stainless nuts and bolts with a bit of 5200. For the holes that the transom wood would cover, you could drill through the wood and fasten the nuts/bolts just like all the others that are meant to hold your transom in place. I would think that would work out OK?



I don't have much experience with 5200... Do you think it might be a better choice than JB Weld if I opt for the method of glueing on a backing plate on the inside then filling/sanding the outside? Is 5200 even sandable, or is it too soft?


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## DaleH (Jul 7, 2016)

> The best thing to do would be have those holes welded.


Here's an option here for filling holes ... done once and permanent: https://www.tinboats.net/forum/viewtopic.php?f=3&t=40538


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## AlexB (Jul 7, 2016)

Dale: There were a couple/few different options discussed in that thread. Which one were you referring to?

EDIT: I assume you're talking about the method you suggested... It sounds like your method is for filling holes through the aluminum AND the wood. I only have holes in aluminum, since I just built a new wood transom piece and haven't drilled any holes in it yet. I'm not confident that the wood will sit 100% flush with the aluminum, and I'm also not sure the two materials won't shift slightly in relation to each other when a load is applied to the transom.

That's why I'm trying to patch the holes in the aluminum independent of the wood. 


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## DaleH (Jul 7, 2016)

AlexB said:


> It sounds like your method is for filling holes through the aluminum AND the wood. I only have holes in aluminum, since I just built a new wood transom piece and haven't drilled any holes in it yet. I'm not confident that the wood will sit 100% flush with the aluminum, and I'm also not sure the two materials won't shift slightly in relation to each other when a load is applied to the transom.
> 
> That's why I'm trying to patch the holes in the aluminum independent of the wood.


In that case, I would use a gooped rivet to patch the aluminum. Where the wood would sit against it I would use a countersink or round burr to create a 'divot' to allow the rivet head/tail to bear up against the wood proper.

The concept of an epoxy patch is good too, where there's a slight bevel on each side to create a mechanical bond to hold it in place. I would use West Systems G-Flex 650 for this, as it is flexible, vs any hard epoxy like JB Weld or Marine-tex.


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## AlexB (Jul 8, 2016)

DaleH said:


> AlexB said:
> 
> 
> > It sounds like your method is for filling holes through the aluminum AND the wood. I only have holes in aluminum, since I just built a new wood transom piece and haven't drilled any holes in it yet. I'm not confident that the wood will sit 100% flush with the aluminum, and I'm also not sure the two materials won't shift slightly in relation to each other when a load is applied to the transom.
> ...



You think the G-flex would do the job in place of JB weld using this method?







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## BigTerp (Jul 8, 2016)

AlexB said:


> I don't have much experience with 5200... Do you think it might be a better choice than JB Weld if I opt for the method of glueing on a backing plate on the inside then filling/sanding the outside? Is 5200 even sandable, or is it too soft?
> 
> 
> Sent from my iPhone using Tapatalk



Yes, it would. A lot of guys on here have patched holes in their hull bottoms with a piece of aluminum glued over the hull with 5200. But they also typically bolt or blind rivet the patch in place, in addition to the 5200. 5200 is not sandable though. If your going to glue an aluminum patch, I'd do it on the outside. Much easier to replace that way. 

I've used 5200 a bunch on my boat with good results. Hard to explain without pictures, but where the top of my gunnel is riveted to the sides of the hull there is some space between each rivet. This creates a space between the gunnel "cap" and the aluminum of the actual gunnel. When my boat is loaded down heavy with 3 guys and hunting gear, spray while underway would splash up there and get in between those spaces leading to some water in the bilge. Actually a lot of water one trip when we had to run 30+ minutes up river to our hunting spot. Probably 8+ inches of water in the bilge. I sealed it all up with 5200 and painted it once it cured. No more water in the bilge from this now and it has held up great over the last year, and I'm sure that area gets fairly stressed.

With all of that said, I wouldn't use 5200 by itself to seal any holes, especially under the water line.


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## AlexB (Jul 8, 2016)

Thanks, BigTerp. 

I keep going back and forth on this, but I'm starting to lean toward filling ALL of the holes with closed end rivets and 5200. This will require me to drill some small divots or voids in the transom wood to account for the back side of each rivet behind the wood. It also seems I'll have to drill those voids, install the transom wood, THEN install the rivets from the outside. If I rivet before installing the wood, I won't be able to slide it up into place.


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## BigTerp (Jul 8, 2016)

Not a problem.

Are you referring to blind (pop) or solid rivets? Either way, I'm not sure how well that idea will work. Both types of rivets leave material on the back side, blind rivets tend to be longer and thinner on the back side and solid rivets tend to be shorter and wider on the back end, if that makes sense? You won't be able to use solid rivets with the wood in place because you won't have access to the back side of the rivet to use a bucking bar. With blind rivets you'd have to make sure you divots are long and wide enough to account for the material left on the back side after setting. Which sounds rather difficult to me to be able to get it just right. They are also not as strong or seal as well as solid rivets.

If your thinking of solid rivets you should be able to get ones with the shaft just a bit longer than the thickness of your transom. Like 1/8" or 3/16" longer. When you set them you should be able to get the shaft on the back end to end up fairly flush with the aluminum of the transom. Is your wood super tight to get back in place? If not, I would think solid rivets would work ok. BUT, if you ever have to replace them you'll need to take the wood back out.


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## AlexB (Jul 8, 2016)

The wood isn't super tight, but it's snug. This is what I had in mind. Let me know what you think.

1) Slide the wood into place

2) Mark the location of each hole onto the wood.

3) Remove the wood.

4) Select a drill bit that matches the diameter of the squished down "back side" of a closed end aluminum pop rivet.

5) Drill ~1/2" into the wood at each rivet location (depth the rivet needs to stick in, whatever that is), and hit the rim of each hole with some sandpaper to clean it up a little.

6) Seal the wood. (I want to do all my drilling BEFORE I seal it)

7) Install the wood, and bolt into place.

8) Apply 5200 to some closed end pop rivets, slide them into place, and pop.

The only problem I see with this method is that I'll have to drill out the rivets if I ever need to remove the wood in the future. The wood won't be able to slide in or out with the rivets in place. Well, it might be able to, but not without scratching up the back side, possibly exposing raw unsealed wood.

I dunno... Each method has its pros and cons. I like the idea of trying to keep the repair flush on the inside so the wood can be removed without too much effort, but I'm not sure if my plan in that little sketch above will work (either with 5200 or JB weld).









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## BigTerp (Jul 11, 2016)

That sounds like a decent plan. Removing blind rivets is much easier then solid rivets. So if you ever have to take the wood out it won't be much of a hassle removing the rivets. Easy to reinstall as well.


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## AlexB (Jul 11, 2016)

I think I'm gonna go for this rivet approach for the holes behind the wood and use some SS bolts/washers/nuts/5200 for the holes below the wood (also below the water line).

The transom will be speckled with bolts and rivets, but as long as it doesn't leak I don't really care how it looks..


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