1972 Boston Whaler Cohasset Restoration

[reelapeelin]

Pull up Google and search "fiberglass repair"...you will get a list of different companies, books, etc...The Mas Epoxy system is generally held in good regard as being user friendly and yields a good result...fiberglassing is an involved application, too much so to be explained in a forum thread and will require an amount of study and trial/error on your part...for instance, the ambient humidity plays a part in how well it sets up, so dig in before you start...I've always wanted to work w/someone who knows what they're doing and learn from them...

One thing I've heard about spider-cracks is that if they aren't dealt with all the way down to the fiberglass (thru the gelcoat) is that they will return...

Is yours a foam-core hull?...if so, be sure the core is dry before proceeding w/your project

If the aluminum brackets you mention are so corroded to the point of being pitted, you may have to have them remade, or there may be a filler on the market to get the surface back again...sandblasting may be required...

[WMalloy382]

Not sure what the best way to work with glass is. I usually use the 2 part pumps and just keep using finer paper to get it smooth.

If you use west system, you can go to the local WM and there is usually a guide you can buy. Its actually pretty easy.

And yes, the original non skid was built into the gel coat. But you will never match the pattern. May as well get it all smooth and add you own non skid.

BTW, I just looked at the pictures again. Thats a 140 on there... Holy Rocketship Batman!! I think the HP rating for that boat is 100hp but i have seen them rigged up to a 135. Wow they fly. Years ago guys would get that exact engine that you have there and just put a 90hp cowl on it to avoid getting stopped by Johnny law...

[OReely]

As reelapeelin wrote, there are entire books written on the subject. Way to variables, situations, and solutions for a thread.

If you have specific questions I'll try to help you as much as possible. I have almost 30 years of professional boat building and repair experience so there's not too much I haven't seen or done.

For example, I bet the gelcoat on the sole is checked (small cracks all over the surface) as opposed to stress cracks (cracks radiating from a corner, edge, or impact). I've repaired many Whalers (as well as other old boats) with checks in the gelcoat. reelapeelin is right about needing to remove the gelcoat or the cracks will reappear.

Your seat supports could be sand blasted to remove corrosion then and powdercoated, painted, or maybe even anodized. Provided, of course, that they are still sound (especially around the screw holes).

Post specific questions here with as much detail as possible and any pictures also

[aimless]

Speaking of 140's, back in the day the marine police here in jersey had 17 Whalers with 135's or 140's and 90 hoods on them. Got that from one I knew at the time.

[2ndCurse]

I would take care of the cracks and add Line-X. I have pics of the bass/flats boat I had done if you're interested.

[Fishinspot]

That will be a nice project. I would definately get as much of the cracks out as possible to repair it right.

[nitz]

I am pretty sure that this is the origional color for this hull. As you can tell in the pictures http://continuouswave.com/whaler/cetacea/cetaceaPage52.html the hull color origionally is white.

As for the non-skid it looks as if it was made into the gelcoat when the mold was made. Am I correct in presuming this? All across the inside of the deck there are thousands of spider cracks around the non-skid, and on the sides. Does anyone have any reccomendations on how to fix these, or should I just sand it all down flat and go from there?

I am new to fiberglass work, so please be patient with my ignorance!

After looking at the pictures I see what you are talking about reapplying the non-skid. This looks like the best option.

Does anyone know of a good guide to fiberglass repair, such as sanding, prepping, and what grits of sand paper work best for which applications?

I can tell you from experience (I have a 1964 Nauset (sp?)) that you must remove all of the old gel coat or those cracks will reappear. I would also be willing to bet that the foam in that hull is loaded w/ water! If you don't remove the water the paint will blister in a short period of time. You can vacuum bag the whole hull and boil out the water if you have a vacuum pump, but since you have to grind the gel coat down you could just cut out the floor and replace the wet foam. Metan Marine has some good pictures on their web site of how to fix it right. If you just want to fix it cheap the linex is porbably the way to go.

[Sailor]

I used to have a '74 Cohassett - always got attention with that console. great little boat. I'll look for pictures of mine as I had a custom windshield made for it and had shorty VHF and loran antenna mounted on the front of the console. I also had the aluminum legs powdercoated and they looked great. One addition I did do was to make some blocks to fit the top of the legs and raise the seat so I could put two 12 gallon tanks under the seat. I re-powered with a 90hp v-4 and that thing would scream. I too had the spider crack problems you are having and I think you need to sand and re-gelcoat. you can get a gel coat removing tool that is basically a planner and you remove the gelcoat easily, but preparation is the key to a good restoration.

[wiley]

Any final updates?

[DJWILLIAMS]

Will update later