1979 Sylvan Rodmaster Bare Bones Rebuild

[79SylvanRod]

Two floor boards are cut. I have some minor trimming and sanding to do. It's not perfect but I'm happy with it. I'll have the gap sealed up with Goop Marine. I'll leave an inch or two caulk free so water can drain into the bilge area.

The third and final floor sheet is going to give me some trouble. I am using 23/32" plywood and front console supports were put it for 1/2" flooring. I'm currently not sure how I am going to make that work without cutting the supports.

 

[LDUBS]

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.

Thanks for circling back. Never dealt with it myself, but I've also heard about concerns with floor cover adhesive over epoxy coatings.

If by filling the voids you mean those along the edge laminations, I think you will be much happier with a putty than glue. I can't recall using PC11 but read it is pretty thick stuff. Taking the time to fill those voids has got to be a best practice.

 

[79SylvanRod]

I spent more time trying to get the bow template made than the other two combined. There had to be an easier way but I have it finished. I still need to add about 1' of cardboard towards the bow.

Question:
How does one get a 3/4" sheet of plywood to fit in this spot with the gunwale supports? I am thinking of cutting out just enough plywood where the red lines are. That will allow me to lower in in place. I have some 1-1/2" aluminum angle that I can cover up the hole with and then caulk the seams. The aluminum angle will cover the red hash marks. Thoughts?

 

[79SylvanRod]

Washed and baked in the sun to dry everything out. Next up is Gflex and Gluvit.

 

[LDUBS]

Question:
How does one get a 3/4" sheet of plywood to fit in this spot with the gunwale supports? I am thinking of cutting out just enough plywood where the red lines are. That will allow me to lower in in place. I have some 1-1/2" aluminum angle that I can cover up the hole with and then caulk the seams. The aluminum angle will cover the red hash marks. Thoughts?

Does the gunnel support screw into the floor? If yes, I think the process might be to slide the floor up under those bulkheads or whatever they are called. That would happen before the rear floors are installed. I understand use of 3/4 ply prevents that. I think there are two options. One is to notch the new floor like you say, then use a short piece of angle to connect the bulkhead to the new floor. The other is to cut the bulkhead back so the 3/4 ply would slide under. Then use a short piece of angle to fasten the bulkheads to the new floor. If hesitant to cut away what was original, I would go with notching the 3/4 ply. (that was on long way to say "makes sense" haha).

I'm not familiar with this model boat. Are there other consoles that will be attached? If so, is the difference in floor thickness going to cause an issue with them?

 

[79SylvanRod]

Does the gunnel support screw into the floor? If yes, I think the process might be to slide the floor up under those bulkheads or whatever they are called. That would happen before the rear floors are installed. I understand use of 3/4 ply prevents that. I think there are two options. One is to notch the new floor like you say, then use a short piece of angle to connect the bulkhead to the new floor. The other is to cut the bulkhead back so the 3/4 ply would slide under. Then use a short piece of angle to fasten the bulkheads to the new floor. If hesitant to cut away what was original, I would go with notching the 3/4 ply. (that was on long way to say "makes sense" haha).

I'm not familiar with this model boat. Are there other consoles that will be attached? If so, is the difference in floor thickness going to cause an issue with them?

I ended up notching the floor since the tunnels didn't seem to attach to the floor. Maybe they rested on it when it was built. I'll have a 1.5" aluminum angle attach the floor to the gunnel support to be safe. I have some BIG gaps between the floor and the boat to make water tight. Not sure how that will happen yet.


Gluvit prep is underway...or still underway. I initially used stainless steel wire brushes to clean the seams and rivets. I decided to follow it up with 80 grit sandpaper. The boat needs the front 2 feet and the last 4 feet to be completed.

 

[LDUBS]

I ended up notching the floor since the tunnels didn't seem to attach to the floor. Maybe they rested on it when it was built. I'll have a 1.5" aluminum angle attach the floor to the gunnel support to be safe. I have some BIG gaps between the floor and the boat to make water tight. Not sure how that will happen yet.

There are a couple schools of thought on this. My first choice would be to not try to seal the floor to the hull. Think about where you want water to drain? Do you want it sitting on top of the ply floor or draining off into the bilge? Additionally, if it is not completely water tight (which it probably won't be), then water will be trapped and potentially cause even more damage. If you use some kind of floor covering, then wrap it around the ply edges. My boat's floor is vinyl which provides quite a bit of protection to the ply. I think the bigger downside is stuff will be falling into the gap.

If you want to close the gap, they may be too large to effectively caulk. Maybe look at things like flexible plastic or rubber T-molding. Might work, except the circular cut-outs will be dicey. .

 

[79SylvanRod]

I'm starting to think about going with EVA flooring. My biggest issue is water getting into the front of the hull and sitting there. Maybe a week ago I washed down the inside, rested the tongue of the trailer on my Ram tailgate, and still had water trapped on all the ribs. I figured water would pass between the ribs and hull but that wasn't the case...

I'm wondering if I could cut a 3 or 4" wide strip of 1/2" plywood to cover those areas and bridge the gap better. A thinner peice of flat aluminum would be the best so their is less of a lip for EVA flooring to go over. Ita all the little decisions that take adds time to these builds.

 

[LDUBS]

Just tossing out some ideas -- instead of 1/2 ply maybe some 1/16 vinyl or PVC trim could be used to cover the gap?

Somewhere is a thread with pics by @thill showing a new ply deck sealed with caulking around the edges.

This one talks about filling a gap with Eva foam

https://www.tinboats.net/threads/eva-foam-mistake.49582/post-512040

 

[79SylvanRod]

That is a great idea. I'll have to take a look the next time I am in the store. Thank you for the idea and the link.

 

[LDUBS]

In that link I posted above @airshot talks about using spray foam insulation to fill the gap, then trimming it down flush. I suppose then you would lay your floor cover on top of that right up to the edge.

 

[79SylvanRod]

Spent some time sanding last night and hopefully applying etching primer and clean metal primer on Saturday morning.

Questions:
- 120 grit good enough for rolled on Rustoleum or should I go to 80grit for more bite?
- Is it best to I wash it tonight and let it dry overnight?

Planned painting steps:
- Wipe with undiluted vinegar
- wipe with acetone
- tack cloth boat
- apply rustoleum self etching primer
- wait 30mins before applying Rustoleum clean metal primer
- wait 24 to 48hrs for primer to dry before lightly sanding with 220 grit and applying Rustoleum Professional color coat with hardener and mineral spirits mixed in.

 

[79SylvanRod]

Boat was wiped with undiluted vinegar and two wipes of acetone this morning. Rustoleum self etching primer was applied before rolling on R's professional white clean metal primer. It ended up being very windy today so the self etch primer did not go on smooth at all. The white primer after that was curing so fast that I could only work is 2' sections. I'll sand it tomorrow and hope for the best.

 

[EricMN]

Boat was wiped with undiluted vinegar and two wipes of acetone this morning. Rustoleum self etching primer was applied before rolling on R's professional white clean metal primer. It ended up being very windy today so the self etch primer did not go on smooth at all. The white primer after that was curing so fast that I could only work is 2' sections. I'll sand it tomorrow and hope for the best.

Great project going there. Brings back a lot of memories of when I did my Northwood!

Nicely done and documented!

 

[79SylvanRod]

Great project going there. Brings back a lot of memories of when I did my Northwood!

Nicely done and documented!

Thank you. I hope some information helps someone else one day. I decided to post progress to keep me accountable and moving forward on this project. A lot to do over the next month.

 

[79SylvanRod]

1st color coat is on!! Paint is tacking up a little too fast still.

16oz - Rustoleum Professional Safety Blue
2oz - Acetone
1 cap full of hardener