1978 20' Proline Classic Rebuild

[melba toast]

This evening, I began the process of building up the exterior of the transom above the old skin. The Coosa install was a good fit, but we still had a couple of small areas to fill with resin and putty. Next, with Mike's guidance, I ground the transition line between the old skin and the new upper portion of the transom. We already had some layers on the coosa from the install. We got a matte biaxial combo, followed by three layers of matte, on tonight. It will probably take a few more layers before the exterior finish work can be done (fairing).



Exterior transition line beveled, taped and ready to glass.



Step complete.

[dirtwheelsfl]

Looking good! For future reference, something i like to do when laying up multiple layers of biax w mat, is lay the last layer on mat side out. It leaves a nice finish and has alot less pinholes to fill than using straight mat. Anything you can do to cut down on fairing is a good thing!

[melba toast]

Haven't tried it... I might try that if what I have left to fill is about the width of a matte/biaxial. You don't have any issues grinding through that one layer of matte and accidentally nicking the biaxial ?

[dirtwheelsfl]

No, you can tell when youve ground through the mat into the biax. But its not really that big of a deal. If youre looking for super flat and fair, handboard that section to the rest of the transom to find the highs in the new section and keep grinding and longboarding til youre satisfied. Your hand will tell you alot more about the surface than your eye will. Until you put a straight edge across it haha.

What are you doing in the stern? Extending the gunnels across the top or cutting motor notch or what

[melba toast]

Probably building the cap across the top, but may have to build a bit of a notch or splashwell depending on what type of bracket or jackplate I use. We are saving that for much later.. After I get floor, stringers, console, and leaning post done.

[melba toast]

Not a lot to report the last 10 days or so. I took a week vacation up to Highlands, NC to enjoy some cool weather... And, returned to over a foot of rain over the weekend. Today, I did grind off the edge of the exterior glass work in the new portion of the full transom, and re-taped for my final layers of fill. I also cut my glass for the final fill of the exterior (2 layers of matte) and the interior of the transom (2 layers of matte/biaxial combo). I also fired off some putty to fill in the edges around the interior of the new coosa transom.I do have a number of chances to work on the project the next few weeks. * As of 6/14, I am fully ready to finish all glass work on the transom Saturday and start grinding the rest of the boat.
 


Exterior glass feathered




Exterior prepped for final glasswork




Interior transom filled with putty(yellow dye added with hardener to make sure the putty was well mixed)




After putty cured, I prepped interior with 4" grinder, and glass cut to fit on 6/14 (dry fit) - (2 layers of matte/biax combo)

[melba toast]

I finished my transom core and glass work today. Mike helped with the lay up.

Next step is to beef up my flange to establish my new floor level. The flange is the old edge of the previous floor that runs along the sides of the interior. I am going up an 1 1/2" or so with the new floor to help the boat to drain better. I want the exact floor level established before I replace the stringer system.

The flange is in ok shape in places, but is delaminating in a few spots. I am grinding underneath so we can tab it back in place. Once it is tabbed in underneath, I can easily repair the cracked and delaminating areas.

Then I plan to core the upper side of the flange with divinylcell, and glass all the way up to the cap. I started to feather out all the old woven that was hidden by the liner previously. Port side is 80% done with grinding.

I also talked with Mike today about my cap. I plan to do the cap last. However, the appearance of the proline is the one thing I dont like about the overall look of the boat. It is too high, too fat, too blocky. It looks like something off an old bowrider. We have a sweet plan to change totally, the bevel on the cap, this winter. Aquasport fans will love it!



Transom ready for glass




Admiring this milestone, Exterior skin - 2 mattes applied - fairing is next




Interior glassed, perhaps another matte or two before finish work, but structurally complete




Interior sides with liner out, will feather and glass over this old woven




Significant grinding today!




Close up of flange and sides

[dburr]

Wow that is progress!!!     Any idea how many grinding hours that represents?

[melba toast]

I'd say counting the transom, probably around 8 hrs so far. I am using a high powered makita with 5" disk, very coarse pad. I'd say another 10 hours and I will have every inch of the boat. I am putting two layers of matte on the sides, and a matte/biaxial in the floor to stiffen it up. Just about all of the boat gets the grinder. It isnt too hot yet, and I hope to get a few mornings in this week.

Having a good fan setup is the key. I have a small box fan in the bow and a hug shop fan outside the stern. I am staying semi comfortable and pulling most of the dust out the back of the shed.

[dburr]

Thanks, always nice to know the time involved.. Then again you don't really want to focus on that either
   

[melba toast]

I got an hour or two in today. Fuel tanks are here. We had them custom built. The idea is to use a smaller tank. I am expecting 5 mpg performance out of this hull when powered by a 115 or 140 4 stroke. That should be plenty of range for what I do 95% of the time. If I run to Chandeleur, then I guess I will bring an extra tank. Otherwise, that should be plenty of gas for Mobile Bay and Mississippi Sound. I don't want the wieght of extra fuel. Plus, I hate having to manage too much fuel, if the boat sits for a month or two in the winter.

Next, I got the transom exterior cleaned up for fairing. The wax and aluminum tape really helped to contain any resin runs and spills. I also finished up most of the port side for my flange work. I may do a little more grinding in the bow tomorrow, depending on my measurements for a casting deck and anchor locker.

Finally, we finished up stringer plans. After looking here and on classic Mako, plus talking to Mike... I am going with 2-4 lb 2" foam stringer material, whatever is available. These stringers will simply be a form for a substantial biaxial/matte layup. I am using 2-3 layers of 0/90 1808, with a layer of 45/45 sandwiched in.




My tank for the proline and Mike's for the 196, 31 gallons... Plenty for of range for a 4-stroke yamaha or suzuki 115 or 140.




Top of the tank view




Lower end and fuel gauge




Transom cleaned up and ready for fairing




Port side essentially ready to build up flange




Sample of stringer foam, 2" foam...




45/45 Biaxial with be used within the stringer layup, along with the 1808 Biaxial 0/90.

[Capt. Bob]

That should be plenty of range for what I do 95% of the time. If I run to Chandeleur, then I guess I will bring an extra tank. Otherwise, that should be plenty of gas for Mobile Bay and Mississippi Sound. I don't want the wieght of extra fuel. Plus, I hate having to manage too much fuel, if the boat sits for a month or two in the winter.

Novel idea.

[melba toast]

I have most of the major grinding on the sides and the bow out of the way. My plan is to glass the underside of the flange with two mattes. We will hot tab it in a few spots and prop it up to get a level flange. Then I am putting an 1808 Biaxial matte from the flange down to the chine, and then to about 4" of overlap on the bottom.

After everything cures, I will finishing grinding the top of the very thin flange. I will core the top of the flange with a 2-3" strip of divinyl cell, probably just clamping it to a wet layer of matte or two. Once that sets, I will trim the edge of flange back to the divinyl cell core, and then glass over the whole dang thing and hopefully be done with it. I will also be glassing the sides later, once the floor is in, to hide my welds.
 


Port side complete, ready for flange glass work




Starboard side complete, ready for flange glass work

[dirtwheelsfl]

Seems like alot of work to save that flimsy flange. It sounds like you are using the divinycell to add height to the flange to raise the deck? If thats the case, i would tab the top side of that flange to the hullsides with a couple layers. When you glue the foam use temporary wood battens on top of the foam and the bottom of the flange and clamp it all together. Hopefully itll all straighten out with that. Then carry on with glassing it in. If it were me though i would just scrap that flange. By the time the deck is tabbed in, that flange isnt really doing much work. Glueing cleats to the hullsides can be done too. You could save it to lay your stringers out with though...something to think about anyway

[melba toast]

We decided to go with a matte/woven/matte to build up the underside of the flange. I glassed from the flange, down to the chine and a 4" overlap onto the bottom. We cut the glass into 12" strips and wet them out on cardboard, and then applied the wet glass and rolled it out. This made it easier to glass the underside of the flange, instead of trying to wet out long sections at a time. Both sides are done, I can now remove the delamination from at the top of the flange and get ready to putty and core the newly rebuilt flange to set a raised floor level.