1985 Rhyancraft (Unplanned) Rebuild

[BrownDogFlies]

Hi everyone. As the title says, I am up to my neck in an uplanned rebuild. I’ve reached the point where I need to ask for a sanity check.

Before I do that, I want to thank the community at large here at Tinboats. I’ve spent hours looking through the archives and I’ve learned a ton. I think I’ve also managed to avoid a number of mistakes. Just wish I’d found this site BEFORE I made my purchase.

OK, progress to date …

-- Acquired the boat in early March. The price seemed right, and it came with a title for both the boat and the trailer (huge deal here in North Carolina).

-- I split my fishing about 50/50 spin/fly, and I chase everything from smallmouth in the mountains to carp in the piedmont to redfish in the saltmarsh. I also hope to duck hunt the Yadkin in the fall. So I want a multipurpose boat that is wide for flycasting, deep for crossing the intercoastal, has lots of deck space and plenty of room for the crew (aka my 9-year-old son). At 15 ft long, between 42" and 48” wide at the bottom and 60” wide at the gunnel, the Rhyancraft seemed to fit the bill.

-- For now, I am planning on running the boat with a 55 lb thrust bow mount trolling motor. Next year I will be getting either a 15hp or 25hp. Keep that in mind for later.

-- Got it home and got to work. Started by rebuilding the decking to add access hatches. Before mounting the new decking opened up the gunnel to run electrical. Noticed that the foam peeking out from under the aluminum floor was significantly darker than the sidewalls. Mashed a finger sized hole and watched water fill the divot. Three hours of demo I had the aluminum sheet for the floor off and 250 pounds of water logged foam in the trash. Later in the week acquired and cut to fit new XPS foam. Went out this afternoon to prep for re-installing the floor and in the process noticed there that THERE IS A HOLE IN THE TRANSOM. About 3/8”, but not drilled. Down low. Would not have noticed it had I not had the floor off and been sitting in the boat drilling out the bases of pop rivets. How it got there god knows.

-- I thought about this for a while and decided the only thing to do was the right thing, so I started to demo the transom. What I found was 1) a 1/8” aluminum plate that was mounted with stainless steel bolts, plain old washers and silicon caulk and covered all kinds of p/o drilled holes for motor mounts, 2) a crumbly wooden transom that broke into 3 pieces, 3) a piece of steel angle iron that looked good from the front but is pitted and rusted on the back, and 4) an aluminum transom that is corroded, pitted, full of holes (both drilled and corrosion) and in need of help. Sorry, I did not get a picture of the pitting today - will add tomorrow.

So, here is my plan, and tell me if I am crazy.

- First I am going to hit it with a wire brush and Goof Off to clean it and then some muriatic acid to stop the corrosion.

- Next I am going to make a new wooden transom out of two ¾” sheets of non-pressure-treated ply which I will laminate together. I will pre-drill all my holes slightly larger than the bolt and paint the thing with 4-6 coats of minwax spar varnish.

- I am going to order a sheet of 5086-H32 aluminum, 0.063” x 20” x 60” , cut it to shape ¼” to ½” narrower than the boat and, using either (1) as few as possible and even those only down low in the corners, pop rivets or (2) 1/4" SS hex bolts, mount it to the EXTERIOR of the transom, using 3M 5200 as a sealant, running a bead around the outside edges of all the holes.

- Next I will apply a heavy coat of JB Weld from the inside wherever there is pitting or a hole that doesn’t get a bolt, using the new aluminum on the outside as a back. After that is dry a good coat of paint.

That’s the plan. Thoughts?

Thanks
--Brown Dog

 

[lckstckn2smknbrls]

Nice boat you have.
Use a stainless steel wheel in a drill or angle grinder and clean it up with a 50/50 mix of vinegar and water.
Use exterior grade plywood. ABX, BCX, CDX the X means it is manufactured with waterproof glue.

 

[BrownDogFlies]

Couple of questions ...

Will a 50/50 water/vinegar solution work in place of muriatic acid? Having read the label I am suddenly less enthralled by the concept of muriatic, if I can get away with vinegar would be the preferred route.

Purchased a 7.5-amp angle grinder at the local big box as well as a carbon cup brush attachment. The brush takes off the paint and the top layer of aluminum. Should I drop back to using an electric drill+brush for the detail work?

Below are pictures after about 30 minutes of brushing. The paint looks blacker because the sprinkler was running. As you can see -- extensive pitting, lots of through holes.

Also, thus far I have avoided removing the the brackets that hold the transom to the gunnels as I don't want to break the braziers. However, there is a layer of white corrosion that I cannot brush unless I remove the brackets. Is it better to go ahead and bite the bullet?

Thanks in advance.

 

[sonny.barile]

Your a lot shorter than I though. :LOL2: Are you planning to keep the deck totally clear of obstructions or do you use a basket for your stripping?

 

[BrownDogFlies]

Sonny-
I am trying to keep the bow as clean as possible - somewhere I saw someone say put the trolling motor and mooring cleats on the right as most folks strip with their the left. I will use a stripping bucket on occasion -- nothing more than a standard big box store 5 gallon pail. Put a inch of water in the bottom and its not going anywhere. Doubles as a tote for getting gear in and out of the boat.
--BrownDog

 

[BrownDogFlies]

Update on the transom repair ...

Spent the better part of this afternoon brushing the aluminum of the transom clean inside and out. On the exterior of the stern the PO had mixed up an unholy cocktail of paint, epoxy and silicone caulk and sealed it under a thick layer of new aluminum. You can see the result below - I put an orange bucket in to boat to make the holes stand out. On the interior god knows what happened -- I am beginning to think they used some sort of PT ply for the old transom. Look at the picture below - how else do you explain the pitting the follows the outline of the old wood?

Anyway, five hours of work summarized in 100 words
- Used an angle grinder with a fine grit finishing pad (similar to a green scouring pad) to sand down to the bare metal
- Used a variety of wire brushes to get out as much of the sugar out of the pitting as I could
- Vacuumed
- Wiped down with a 50/50 mix of 4% vinegar and water
- Repeated 1-4 several times
- Painted with OSPHO and let dry

During the process I found more pitting, this time in the hull floor between two ribs (see pic below). After initial freak out, determined that the pitting is not as bad as originally thought and isolated to the rear of the boat. So, this coming Friday morning I am planning on taking it to a local carwash and powerwashing the interior, pulling it into the sun to dry before painting OSPHO over everything that even remotely resembles a pit, letting it dry for 30-45 minutes, then rinsing it clean.

Thoughts?

Thanks in advance.
--BrownDog

 

[Jake11]

Looks like an improperly maintained salt water boat to me. I bought a 14 ft alumacraft a couple years ago down in VA that had about ten layers of house paint on the bottom and when I removed it, it looked just like that. Guy had left it docked in a salt creek behind his place forever. From my experience 5200 is your friend. If you're putting a whole new sheet of alum on the transom I would slather that whole sucker with 5200 before you bolt it on. Let it cure properly and you'll never have another problem with it. I have about a 4 inch crack in the hull near a flex point of that same alumacraft that has held up with a bead of 5200 for 2.5 seasons now. Good luck and its coming along.

 

[DaleH]

Looks like an improperly maintained salt water boat to me.

Looks like it to me too ... and if you see any evidence of a white layer 'inside' that aluminum transom panel, then it should be replaced, not repaired.

See this post here for how I ran into the same thing and ended up replacing the entire transom piece. I too bought a boat believing it needed a 'little repair' that turned out to be more work than I had imagined:

https://forum.tinboats.net/viewtopic.php?f=3&t=37548

Once a saltwater chloride reaction is embedded in the crystalline structure of the aluminum, it is self-propagating, and travels internally through the inter-granular boundaries. Read this through! In my case, when looking at the existing corrosion holes, I could see 3 layers to the aluminum, like looking at your 1st 3 fingers, where the outside ones were aluminum and the inside was a white or pink colored stain.

I used a carbide burr on a Dremel tool into say an 1/8” corroded hole, cutting back until I had cut out all of the corrosion and only had what appeared to be all aluminum. Well, that 1/8” hole might now be 1/4” to 3/8” big. Like yours, it only appears to be in a few places, so I thought ‘Heck, that was ugly, but not too bad, maybe I can salvage it like you – with an extra aluminum panel and some epoxy’. Then when working the boat, scraping a spot 6” away from where any untreated wood had been, the edge of the scraper went RIGHT THRU the aluminum like it was made of paper! Rot had permeated all throughout the piece … even inches away from where any untreated/uncoated wood had been in the transom.

On a saltwater boat, any wave/water action to the stern soaks the wood transom with the saltwater, which acts as an electrolyte. Add in your aluminum hull as the less noble metal and the stainless steel fastener, and you get an IDEAL environment for galvanic corrosion. There is no cure – repeat – there is no cure! If your hull corrosion damage is THAT excessive you should really replace that panel.

That’s what I chose to do … I have no choice … as I have 2 little girls who will be my crew that will be on my boat in saltwater estuaries and I want it to be safe for them. Heck, for me too!

 

[DaleH]

FYI, on the boat I bought someone tried the extra piece of aluminum laminated to the original hull with 3M 5200 and it didn't work. As unless 100% sealed saltwater WILL get in there. Not IF, but WHEN! And when I had separated the 2 sheets during my demo ... I was removing handfulls of salt buildup. That is NOT good ...