mirrorcraft northport troller tinny - need rehab guidance

[dzurinko]

Re: mirrorcraft northport troller tinny - need rehab guidance

Hey bonz, thanks for the encouragement. Now that the floor is out and its cleaned up, I can start the restoration. There is no foam under the floor. Foam only in the side boxes. I had one of these same year/size Northport Trollers from 1987 (bought new) until I sold it in 2001 to go to a bigger 26' Sea Ray. Then when I retired a couple years ago, I sold the Sea Ray. Missing my old Mirrorcraft Northport troller, I found two on craigslist. One in your neck of the woods (Wisconsin) for $2600 but I didn't want to drive that far from NJ. And one about 12 miles from me for $900 so I GRABBED it. This one has the consol with a 35hp and my old one was a tiller (9.9). But I always loved that boat as I will love this one. Thanks again for the info on the battery charger. I go to Black Lake upstate NY each year in Sep so I have a goal date in mind. Let us know how you're making out on your restoration too. Always eager to learn from others doing same type of thing.

 

[dzurinko]

Re: mirrorcraft northport troller tinny - need rehab guidance

I folks. Starting to plan what the inside of my tinny will look like. I have one issue that I need some folks to weigh in on. Here is my issue: My Mirrorcraft Northport Troller originally came with one long wooden tapered stringer bow to stern down the center. Towards the bow, the stringer about 5.5 inches high, made of oak. The boat is a deep "V" style so the ribs curve up on port and starboard in the front. Screws attach the floor to the center stringer and the edges of the floor attach up on the ribs 5.5 inches above the boat bottom. The last 3 feet towards the stern the stringer tapers down to nothing and the boat bottom is flat so there is no longer a curve to the ribs. They lay flat in the stern. Consequently, the floor in the stern is sitting atop the ribs only 3/4 " above the boat bottom. On heavy rain days, this could cause water to actually touch the bottom of the floor especially if I'm by myself and the bow rides higher, stern lower. The bow end is plenty high so there is air under the floor, unlike the stern. Over the plywood floor will be marine carpet. Is there a material other than plywood that I can carpet that I can use in the last 3 or 4 feet that could lay in water if necessary and not worry about rot. I was also thinking about raising the floor an inch or two near the stern but then I'm afraid I'll create a tripping hazard as there will be a two inch step up. This boat will have a helm installed. Should I make a raised deck in the back for storage of battery, gas, and bilge? OR...if I simply coat my plywood floor real well will it stand up to water infiltration? Not sure what to do here. Looking for some ideas.

 

[ezmobee]

Re: mirrorcraft northport troller tinny - need rehab guidance

Look up "coosa board". Warning: it ain't cheap. I think some others on here have used some sort of honeycomb like product on their glass boats but I don't know what any of that is called.

 

[dzurinko]

Re: mirrorcraft northport troller tinny - need rehab guidance

Youre right. Expensive! But awesome. I may have to use a piece near the back where my floor is right on the ribs. Thanks for the suggestion. I never heard of it before.

 

[Woodonglass]

Re: mirrorcraft northport troller tinny - need rehab guidance

The honeycomb board is Plascore - $100 bucks for a 4x7' sheet. Pretty cool stuff.

Plascore - Honeycomb Cores – Honeycomb Panels Products

 

[dzurinko]

Re: mirrorcraft northport troller tinny - need rehab guidance

Got my transom out yesterday. Lots of junk on it like whitish clear jelly. Have no clue what it was. It was also all over the inside wall of the transom sheet aluminum where the transom board touched it. Scraped it off easily with a 4" putty knife. Today it was dry and like a crusty white mold or something. Wire brushed the aluminum to get that stuff off. Anyone know what that stuff is? Finally found a supplier in Southern NJ for 3/4" Marine Ply. Took two weeks to find. $90 a sheet but regular 3/4 exterior plywood would have been $35 or $40. So for an extra hundred, I'll use marine plywood. Went to replace the bearings on the trailer while I'm gluing up and clamping the new transom and discovered the spring hangers are soooo rusted that I cant believe I got it home from the PO. On one of the hangers, there was less than 3/16 of metal around the bolt that holds the spring to the hanger. The axle is attached to the spring so if that little piece of 3/16 metal broke, the axle would have come off the trailer while towing. So now there is a delay continuing with the boat rehab until I get new hangers and springs on the trailer. Once my transom sits in clamps for 24 hours (used gorilla glue), I'll throw it on the table saw and trim it to the right dimensions. I cut it 1/2 large all around so I can trim it for a perfect fit. Next I'll have to get more marine ply for the floor and storage compartments. The boat had the original 1/2 plywood on the floor from 1987 covered with boat carpet with a rubber backing. Any suggestions on sticking with 1/2" on the replacement floor or upgrading to 3/4? Suggestions?

 

[classiccat]

Re: mirrorcraft northport troller tinny - need rehab guidance

Personally I'd stick with 1/2" to minimize weight and cost. You don't have much distance between the stringer & rib where the floor attaches.

 

[jigngrub]

Re: mirrorcraft northport troller tinny - need rehab guidance

Personally I'd stick with 1/2" to minimize weight and cost. You don't have much distance between the stringer & rib where the floor attaches.

Weight difference between 1/2" and 3/4" plywood is 25 lbs. per sheet so we're probably not talking about 100 lbs. here.

The difference in cost is minimal depending on what kind of plywood is chosen.

3/4" is a much stronger build, and it feels like it when you walk on it too. 3/4" also holds fasteners for accessories and hardware much better than 1/2" does, it takes barely anything to strip a screw out of 1/2" plywood.

 

[dzurinko]

Re: mirrorcraft northport troller tinny - need rehab guidance

I have access to both 3/4 and 1/2" Marine plywood only minutes from my house. The 3/4" is $90. I don't know what 1/2" is but they have it in stock. I'll need two sheets for the floor. So either is easy to get. The distance between the centerline stringer and the ribs is about 14 inches. I noticed when tearing down, the manufacturer used 1/2 on floors and the tops of the side foam compartments and 3/4 on the raised front deck/anchor storage area. It originally came with two pedestal seats. It also has a side consol that was attached to the gunnel and the floor. It looks like the 1/2 plywood was doubled where the seat plate mounts to the floor for added grip.

 

[jigngrub]

Re: mirrorcraft northport troller tinny - need rehab guidance

3/4" will be much bettter if you plan to use pedestal seats, 1/2" requires backer plates for pedestals. You can use stainless steel "T" nuts and oval head 1/4-20 machine screws to fasten your pedestals with and never have to worry about them for a permanant installation instaed of trying to use the #12 stainless sheet metal screws through the top like the rookies do.

Check and see if your lumber supplier has MDO plywood, it'll be cheaper and is a better decking material for aluminum boats IMO. It already has 1 coat of phenolic (epoxy) resin on it and it's made for use in wet applications like outdoor sign making and concrete form work.

 

[bonz_d]

Re: mirrorcraft northport troller tinny - need rehab guidance

For what it's worth, when i did the decking in my 1984 Lund, Lund was using 5/8" ply and that is what I replaced it with. The span in the Lund is also about 14" and there is no give in the decking at all. Also from what I can tell it looks as though Alumacraft also used 5/8" ply in the 1988 Classic 16 that I'll be doing as soon as the weather warms enough.

Also remember that every bit of added weight reduces the total carry capacity of the boat. Which does make a difference in these smaller boats.

 

[dzurinko]

Re: mirrorcraft northport troller tinny - need rehab guidance

Thanks Bonz. I used to have this same model boat back in the late 80's when it was new and it had 1/2 plywood and it always seemed solid to me. But there is a lot of talk on the forum to go to 3/4. I'm not so sure I want the additional weight or expense and that's why I was asking others what they thought. The old 1/2 was very solid and I never felt like it was bending or sagging. The front raised deck came with 3/4 so I bought a sheet of that. What I didn't use on the transom, I'll use for the front triangle shaped raised deck. But my next step is getting the decking and I don't want to buy 3/4 unless its necessary. Its an extra 30 or 50 pounds that I'd rather use by having a spare accessory battery. One question, I'm getting ready to Epoxy Resin my transom. Should that be done BEFORE I redrill holes or drill holes first then coat with resin? I don't want to close the holes down too much. I'm afraid if I do, I wont be able to get all the bolts back in and I'll be re-drilling again. I DO have 5200 to coat all the holes when replacing the hardware.

 

[jigngrub]

Re: mirrorcraft northport troller tinny - need rehab guidance

Thanks Bonz. I used to have this same model boat back in the late 80's when it was new and it had 1/2 plywood and it always seemed solid to me. But there is a lot of talk on the forum to go to 3/4. I'm not so sure I want the additional weight or expense and that's why I was asking others what they thought. The old 1/2 was very solid and I never felt like it was bending or sagging. The front raised deck came with 3/4 so I bought a sheet of that. What I didn't use on the transom, I'll use for the front triangle shaped raised deck. But my next step is getting the decking and I don't want to buy 3/4 unless its necessary. Its an extra 30 or 50 pounds that I'd rather use by having a spare accessory battery. One question, I'm getting ready to Epoxy Resin my transom. Should that be done BEFORE I redrill holes or drill holes first then coat with resin? I don't want to close the holes down too much. I'm afraid if I do, I wont be able to get all the bolts back in and I'll be re-drilling again. I DO have 5200 to coat all the holes when replacing the hardware.

So what's going to support the flimsy 1/2" decking? Foam? That's what the manufacturers use to make the 1/2" decking feel solid, expanding foam directly underneath the 1/2" decking. This is also why the decking rots out quickly on the boats, because the deck sits on top of the foam and absorbs any moisture between the deck and foam.

 

[dzurinko]

Re: mirrorcraft northport troller tinny - need rehab guidance

Hi Jig, No actually there is no foam under the deck. The foam is in two compartments that run down both sides of the boat and are connected to the gunnels and the floor which adds to rigidity. The previous deck connected to a centerline stringer and to the ribs on the edges. The distance from the centerline stringer to where it connects is 13" and the ribs are 9" apart toward the front of the boat and 12" apart near the rear. So the most the plywood would span is only one square foot of air space. I'm no engineer, but 1/2" subfloors in houses (covered with carpet) are resting on floor joists 16" on center allowing for 14 1/2" of airspace. So there is a lot more airspace under my living room floor than my boat deck and my boat deck doesn't have to carry heavy furniture. Plus, subfloors are only cheap plywood with air pockets all over the inside and outside and I would only use solid marine plywood coated with epoxy resin. That being said, you make a great point about attaching pedestal seats to 1/2" ply. I agree, it wouldn't work well. The manufacturer doubled the plywood under the seats. The front seat sat slightly to the port side and the back seat sat slightly to the starboard side. Not only does this help with weight distribution but it allows for the doubling of plywood where there is no stringer to contend with. Great idea with the stainless "T" nuts and machine bolts. I think I'll steal your idea.

 

[jigngrub]

Re: mirrorcraft northport troller tinny - need rehab guidance

Great idea with the stainless "T" nuts and machine bolts. I think I'll steal your idea.

That's not my idea, that's OEM/factory installation on the majority of boats today and the way mine came from the factory.


BTW... residential subflooring is 3/4", roof sheathing is 5/8", and the 1/2" is used for wall sheathing... I'm a carpenter by trade.

 

[dzurinko]

Re: mirrorcraft northport troller tinny - need rehab guidance

I need to repaint the inside gunnels of this aluminum Mirrorcraft. I'm looking for recommendations. I plan to use either Majic Paint or Rustoleum on the hull after proper prep, but for the inside, I don't want the gloss paint that will blind you on a sunny lake. I need something that will hold up as well as Rustoleum but in a flat or matte finish. Looking for an off white or pale light gray. Any suggestions????

 

[bonz_d]

Re: mirrorcraft northport troller tinny - need rehab guidance

I'd still look at Rustolium. Other than the Topside paints.

 

[dzurinko]

Re: mirrorcraft northport troller tinny - need rehab guidance

Hi Bonz, do they make a semi-gloss? I don't want the shine on the interior, it'll blind me on sunny days. Seems all they have are glossy. Maybe I'm not looking on the right site.

 

[dzurinko]

Re: mirrorcraft northport troller tinny - need rehab guidance

After stripping everything out of this tinny, I made and drilled my new transom. I'm having a new splash well made so can't reinstall until my splash well is done. Got the tinny off the trailer ready to begin sanding and then zinc chromate on the scratches. I replaced the bearings on the trailer and noticed the springs and leaf spring hangers we're totally shot. There isn't even enough hanger left to hold the springs and axle on the trailer. Dangerous! Can't believe I got it home 15 miles in that shape. So got a mobile welder coming out this weekend to weld on new hangers. Once the suspension is redone on the trailer, its back to preparing the hull for paint, JBweld some thin spots on the back, reinstall the transom, then paint the exterior of the boat. Then I can begin rebuilding the new deck, and installing bilge pump, console, wiring all my toys, and rehanging the tilt unit and 35hp engine.