1979 Sylvan Rodmaster Bare Bones Rebuild

[79SylvanRod]

Hello everyone,

This is my first post and first aluminum boat. I picked up a gutted 1979 Sylvan 16' Rodmaster (similar to Starcraft 16' SS). The previous owner started the rebuild process by sanding the hull to bare aluminum and replacing the transom. The boat will be left in the water for one week each year and then put in the water for a few hours a couple times the rest of the year. It will be stored in my garage when not in use. I mainly bought this because I like a project and I dislike renting boats while on vacation.

Interior Build Plans:
- Gluvit interior seams. I have about 4 or 5 rivets at the bow to tighten up.
- blue/ gray foam boards from a big box
- BCX 3/4" plywood
- Old Timers Formula sealant
- Rust oleum professional oil-based enamel painted on both sides of the wood
- Stainless steel screws with Ultra Tef-Gel

Interior Unknowns:
- Goop Marine or 5200 sealant along plywood to hull seams?
- Non-skid texture paint or EVA marine foam flooring over Rust oleum painted floor. I am leaning to non-skid texture only because its easier to clean.

Exterior Plans:
- Buck some rivets back into place.
- Apply G-flex to bow and transom leaks.
- Apply Goop Marine over Gflex after its cured.
- Goop over remaining rivets and seams. I wont be flipping the boat over so gravity and Gflex will not work together in my case.

Painting:
- Gunwales will be painted with Rust oleum Professional oil based enamel in safety blue.
- Aluminum sanded with 80 grit sandpaper, washed down, dried, wiped with 50/50 water and vinegar solution, Rust oleum etching spray can primer, Rust oleum clean metal primer, and then 3 color coats.
- Rust oleum clean metal primer and color coats will have Tractor Supply hardener for enamel paints and I'll thin with mineral spirits.
- I would rather have the interior be painted a gray, but I have a whole gallon of safety blue I need to use up.

I am open to recommendations, tips, tricks, etc. This is a semi-budget build because it will not be used very often and will probably be replaced with something larger in 10 years or so. I will have some questions on trailer bunk setup coming up later on. I hope you all enjoy the progress coming. My goal is to be done by end of May... A lot of late nights are in my future.

 

[79SylvanRod]

Here are some photos of the project. I have identified and labeled all the interior peices.

 

[79SylvanRod]

I filled the boat with water to my presumed waterline. The only three areas that leaked were at the bow and both side of the transom. The transom leaks were very minor and only looked wet. The bow had a decent leak. Water would drip off at a consistent 2 to 3 second interval. I used a stainless steel wire brush and cleaned up all three areas. Now I just have to convince my wife to help me buck a few rivets.

I have Gflex and Goop marine already. My plan is to use the Gflex to seal inside the void and then cover it with Goop marine after the Gflex fully cured.

 

[Stand Up]

Welcome to the forum @79SylvanRod . This looks like a great project boat. Post pics of your progress for us to learn from.
With a nice paint scheme, it's going to be great!

 

[79SylvanRod]

Welcome to the forum @79SylvanRod . This looks like a great project boat. Post pics of your progress for us to learn from.
With a nice paint scheme, it's going to be great!

Thank you Stand Up! I'll do my best to keep up with the photos.

Do you know where most people end their 3/4" floor on the sides? Putting the plywood on the #1 lip in the photo seams like it could put added stress along those rivets.

Keeping the floor off the lip would require a good gap sealant unless people cut the edges at an angle to help close the gap.

 

[LDUBS]

I was going to suggest 1/2 ply for the floor if it had enough support. Looks like you already have 3/4. If off the lip, what supports the edge of the floor? Seems to me it should be up on the step, but unless your plywood is really sagging, that doesn't seem to be the case.

That is a great boat. I look forward to watching your rebuild.

 

[79SylvanRod]

I was going to suggest 1/2 ply for the floor if it had enough support. Looks like you already have 3/4. If off the lip, what supports the edge of the floor? Seems to me it should be up on the step, but unless your plywood is really sagging, that doesn't seem to be the case.

That is a great boat. I look forward to watching your rebuild.

I originally wanted to go with 1/2" to save on weight. When I placed my spare 3'x4' sheet of 1/2" ply I noticed the floor had some deflection. I decided on 3/4" so I didn't have to worry about my foam boards supporting my weight.

I might take the wood up to the seam above those rivets. It will look and seal better.

 

[79SylvanRod]

Rear and middle cardboard templates are made. I promise no special beverages were consumed and the cause of the angle cardboard. I figured I could give the templates more rigidity if I taped support pieces at an angle.

Once the front is done I'll be feeling better about the build.

Leaking rivets were also bucked back to being snug. Gflex will be happening next and then back to the floor template.

 

[LDUBS]

Are you going to have the floor in sections? Mine is that way. I like it because I don't have to remove the whole floor to access below.

 

[FuzzyGrub]

Some things to consider:

The cardboard templates represent the bottom of your planned 3/4" deck. The top will be wider in most cases, with the bow area usually at the most angle. Typically a 45 degree max with most saws. The better you match it, the less you have to fill the gap.

One thing I never considered when doing my first restore, was mice. The boat had an open area, like yours, for the drain access and bilge pump. This opening was like leaving the hotel door open. Mice love building in the foam and chewing tunnels thru it. Getting the mice piss smell out is a job too. If they are an issue in your area, some heavy metal screen might be in order.

 

[79SylvanRod]

Are you going to have the floor in sections? Mine is that way. I like it because I don't have to remove the whole floor to access below.

Yes, the floor will be in 4' sections. I might seal the gaps between floor sections with caulking. I haven't made up my mind yet. I haven't done enough research.

 

[79SylvanRod]

Some things to consider:

The cardboard templates represent the bottom of your planned 3/4" deck. The top will be wider in most cases, with the bow area usually at the most angle. Typically a 45 degree max with most saws. The better you match it, the less you have to fill the gap.

One thing I never considered when doing my first restore, was mice. The boat had an open area, like yours, for the drain access and bilge pump. This opening was like leaving the hotel door open. Mice love building in the foam and chewing tunnels thru it. Getting the mice piss smell out is a job too. If they are an issue in your area, some heavy metal screen might be in order.

I never thought of mice... Since this will be stored in the garage I should be fine. If I ever need to store it outside I might make a plywood cover to fit over the bilge area and place two 10lb weight on it. Thank you for the heads up. It would have never crossed my mind.

 

[FuzzyGrub]

I never thought of mice... Since this will be stored in the garage I should be fine. If I ever need to store it outside I might make a plywood cover to fit over the bilge area and place two 10lb weight on it. Thank you for the heads up. It would have never crossed my mind.

Yea, only something to consider. FWIW: It never happened when boat was stored outside with a tarp. They infested it when it was in a shed, but still had the cover left on. It wasn't near the main house, though.

 

[airshot]

Yes, the floor will be in 4' sections. I might seal the gaps between floor sections with caulking. I haven't made up my mind yet. I haven't done enough research.

Caulk might be to permanent in case of a problem. Consider using a self stick vinyl trim available at most home stores. It will give a better finished appearance and easy to move/ remove I'd floor needs removed.

 

[LDUBS]

Caulk might be to permanent in case of a problem. Consider using a self stick vinyl trim available at most home stores. It will give a better finished appearance and easy to move/ remove I'd floor needs removed.

This here is a great suggestion. Caulking a butt joint like that to make it look neat usually won't work out very well.

 

[79SylvanRod]

Caulk might be to permanent in case of a problem. Consider using a self stick vinyl trim available at most home stores. It will give a better finished appearance and easy to move/ remove I'd floor needs removed.

That is a great idea. Thank you for the recommendation. I'll look into it.

 

[79SylvanRod]

Wood sealing questions:
- Should I apply the OTF before I fill the plywood voids with waterproof wood glue? If the wood doesn't swell with OTF then I think this would be better.

- How long does it take for the OTF to dry before I can screw it down?

- Do I need to keep coating it until it stops soaking in?

- I plan on using HR waterproof wood glue. Do think this this will be okay of should I look into something else to fill the plywood voids?

 

[79SylvanRod]

I still have to research more on my above questions.

I am working on cleaning up around seams and rivets inside the hull. I am hoping to Gluvit on the inside and Gflex on the outside by this weekend. Goal is to have foam and wood floor installed before May.

The stainless steel wire wheel is making quick work in a majority of the areas. I am having difficulty with two things. There is some type of waterproof coating in the bow. It's pretty tough near the bottom and is flaking off closer to the top of the application. The other area I am having a hard time with is cleaning the seams under the metal stringers running down the middle. Not a big deal.

 

[LDUBS]

Wood sealing questions:
- Should I apply the OTF before I fill the plywood voids with waterproof wood glue? If the wood doesn't swell with OTF then I think this would be better.

- How long does it take for the OTF to dry before I can screw it down?

- Do I need to keep coating it until it stops soaking in?

- I plan on using HR waterproof wood glue. Do think this this will be okay of should I look into something else to fill the plywood voids?

I wonder how the cost of OTF components compare to penetrating epoxy? I suspect the price of spar varnish makes them relatively comparable. If so, why not use penetrating epoxy. I now little about OTF other than what I read. I do know that penetrating epoxy provides excellent protection on plywood.

Just curious, what is HR waterproof glue?

 

[79SylvanRod]

I wonder how the cost of OTF components compare to penetrating epoxy? I suspect the price of spar varnish makes them relatively comparable. If so, why not use penetrating epoxy. I now little about OTF other than what I read. I do know that penetrating epoxy provides excellent protection on plywood.

Just curious, what is HR waterproof glue?

I did look at epoxy and went back and forth on it for weeks. What ultimately swayed my decision was already having a gallon of mineral spirits and others having issues with flooring adhesives sticking to the epoxy.

I meant to say HF for Harbor Frieght. I went a different direction and just bought a small thing of PC-11. I hope the OTF will play nice with it.