TOPIC: Winter stroage and more cracks!

Wanted to put the boat under cover, but because of a big oak stump in the way, could not get it in the pole barn. I am able to get it where the new expansion is going though, and plan to tarp it to protect it best I can. (If I had 300 bucks, I could put a roof over it!) I'm burning the oak stump. Takes a while, but doesn't hurt my back.

Took the motor off the boat Saturday. Cleaned up the transom and splash pan yesterday and noticed new cracks that had not been there before. I say this with some confidence, as I clean these areas a lot. One is a crack between the floor and wall on the starboard side of the custom splashpan I built. These nice smooth edge transitions I got like that with body fill. I wonder if I could "V" the crack out and fill it with something like 3M 5200 for flexibility, then overcoat it?

The other crack really has me scratching my head. It's about 1/2 way down the transom over on the starboard side. "V" it out and fill with what before I touch it up?

Man o man, it always sumpin. Especially when you consider it's mild, meek mannered Frank who hardly takes his old boat over 20 mph, and avoids jumping waves like the plaque...

frank, i think your profile pic jump is responsible. ron

Ron, I'm pretty sure that pic was photoshopped!

Frank

Break out the waders, its gettin' pretty deep.......

frank im sorry to hear that,and im no expert but i like fiberglass resin jelly,instead of bondo it works exactly like bondo,but i think its a bit stronger.john

Gee, great idea Ron, thanks! I've got some of that around here I've never opened. I'll give it a try.

Frank

thanks frank...i use it in all my boat restorations. hehe

Frank,

If it were on my boat - I'd just live with them. But, that's me & not you. My guess on the splashwell at least, is the stress crack is superficial. Bondo & paint don't flex very well. These boats can vibrate, flex, and move quite a bit. Any material at a stress point that is rigid - will crack. The longest lasting restorations avoid the use of automotive fillers, and the finish is gelcoat.

That's a good lookin' boat you've got

I'm gonna try again on the deck anyways Bruce. Not only did I get poor coverage, it turned out splotchy. I have a small crack on the starboard bow I'll do, and I'll use John's idea for both that and the crack in the splashpan. The crack on the transom is more of concern. I don't want water getting in!

I rebuilt this boat to be very stiff. The new splash pan was built in place and really tied the back end together, while the rest of the boat (except where I couldn't get way up near the point of the bow) was glassed along the inner hull/deck seam in two layers for rigidity. I put a lot of hours on this boat this past summer - it only seemed right after working on the darn thing so long! (I figure I burned 200 gallons of gas this 1st season.) It has a number of scratches and dings from docks, all on the deck, so it won't be too hard just to re-paint that.

Thanks!

Frank

Looking at where the damage is will tell you alot. For the splash well to have cracks like that can be several things. Maybe to much viberation and the glass could have been a little thicker in the radius. But with the crack in the transom showing up also something strongly suggests that there is flexing. This flexing has found the two weakest points and let you know.
I do not remember what structure you had for strenght to the transom. But could some knees be added under the splashwell to the transom and tie in with the floor and bottom of the splashwell. Somewhere you need to add more strenght.
As to fixing the damage althouht I love the resin gell. That damage area needs to be addressed as if you had a hole in the boat. Grind out the damaged area in a large v like shape going deep were the cracks are and lay several layers of glass over this then sand her down.
Its always a bummer to have a finished project and then have something like this show up. But it is very fixable and hey anybody that works on these boats has some snafu's.

D

It would be very hard to put knees in, but that is a very good point.

This boat came with one cross brace, sorta centered between the two I installed. I wanted a very solid transom for future placement of a heavier motor (i.e., 4 stroke), so I focused on building lateral strength in. Most people that restore these boats just go with one lateral member, others eliminate them and go with knees. After looking at a lot of other Power Cat projects, and given I needed to build a custom splash pan, I went with two, with the top one being the foundation for the new splash pan.

I don't have a good shot of everything that is under the splash pan, but in the starboard hull is the battery, then moving towards port is my PT&T unit, then my two 6 gallon gas tanks. With the cross braces that are currently in there, I'm not sure how I could put knees in.

Frank

Here are a couple pictures of boats that Dick Davis built. Maybe this might be of some help.

D

From looking at the pic this is what I would work toward. Setting a pair of knees on top of the tunnels and tied into the crossbraces.

herters59 wrote:

Here are a couple pictures of boats that Dick Davis built. Maybe this might be of some help.

Dick Davis gave me specific advice on doing what I did.

Frank

classicfins wrote:

From looking at the pic this is what I would work toward. Setting a pair of knees on top of the tunnels and tied into the crossbraces.

That would be the ticket if the deck was off Doug. It would be incredibly difficult for me (maybe not others) to do that with the splash pan glassing the deck and hull together in the back. I might be able to do it on the starboard tunnel, but would be relegated to only one 6 gallon gas tank if I did it on the port tunnel. I think it would be easier to fix cracks as they come up!

The transom is two pieces of 3/4 marine mahogany plywood laminated together, glassed in with the two crosspieces that flare out towards the side of the boat and are glassed with three, four, maybe 5 layers of mat into the sides of the boat. I spent some time at it trust me!

Tell me, what would knees like that do? Eliminate the transom crack or the splashpan crack?

Frank

With the transom and crossbraces both running horizontally you still have the possibility of a "bowing" effect. I would think the knees running vertically would help to elimanate some of that bow/flex, kind of like added a post under a long, sagging beam on a shed.

And to be honest.. If it was mine... I would run it as it is and not worry about it. I think no matter how much glassing you do you're always going to have an issue with the well because the surrounding areas are glass, but the spalshwell is wood with glass over it. I would think that the two different materials are going to flex differently and not with each other. If I did anything, I would V it out a bit and use an automotive seam sealer like is used on the drip rails of older cars and trucks. It seals, fills the void, flexes, is paintable, and exterior weather and water is not a problem.

Thanks Doug. I was thinking about v'ing it out and using 3M 5200? You think seam sealer would be better? I'm pretty sure I have both those products around. I used to have an old pick up!

What would you fill the transom crack with? Same stuff? Maybe that's a good place for that resin jelly stuff. That is much more of a hairline crack then the one in the splashpan.

Frank

PC1000 wrote:

classicfins wrote:

From looking at the pic this is what I would work toward. Setting a pair of knees on top of the tunnels and tied into the crossbraces.

Tell me, what would knees like that do? Eliminate the transom crack or the splashpan crack?

Frank

Knee braces keep the transom from "rocking" caused by the thrust plane of outboards. Picture this: The motor is connected at the bracket, near the top of the transom. Thrust is generated at the prop, about two feet LOWER than the mount. Every time you hit the throttle, its like a lever effect, pushing in towards the bottom of the motor's transom bracket. Same thing happens when you trailer without a lower unit brace and hit a bumpy road (everywhere in Michigan). Think of how these forces are acting on your transom and beef up accordingly.

One other possibility I don't believe has been mentioned yet - Heat cycling. Fiberglass & wood expand and contract at different rates. If a wood panel is attached to a fiberglass panel with a thin layer of glass, the joint gets regular stress from the dissimilar materials. Also, if you bridge a gap with fiberglass, kitty hair, etc. The edges often will develop little cracks. This can be seen when large holes (instruments, through fittings, etc. have been filled but not adequately ground out prior to filling with glass. Even if it is done correctly, a "halo" of the hole can show back up. This is why a lot of restorers re glass the entire deck of some boats, to help prevent repaired areas from showing through. On mt Skagit, I cut the transom core 3/4" shy of the top edge and filled the rest with solid fiberglass. The top edge was then ground & filed perfectly flat. Then it was gelcoated. It looked like a factory new transom edge. After a couple years some tiny cracks started to appear where the outer skin meets the top edge. This is a curved transom and it is over 1 1/2" thick.

Kerry wrote:

PC1000 wrote:

classicfins wrote:

From looking at the pic this is what I would work toward. Setting a pair of knees on top of the tunnels and tied into the crossbraces.

Tell me, what would knees like that do? Eliminate the transom crack or the splashpan crack?

Frank

Knee braces keep the transom from "rocking" caused by the thrust plane of outboards. Picture this: The motor is connected at the bracket, near the top of the transom. Thrust is generated at the prop, about two feet LOWER than the mount. Every time you hit the throttle, its like a lever effect, pushing in towards the bottom of the motor's transom bracket. Same thing happens when you trailer without a lower unit brace and hit a bumpy road (everywhere in Michigan). Think of how these forces are acting on your transom and beef up accordingly.

Kerry, I have had a transom saver on it from day 1. The thrust thing could be it though. And gee, that would be a problem, because it sure is fun pushing that throttle all the way forward while trimming the motor out...

Frank

Bruce Gerard wrote:

One other possibility I don't believe has been mentioned yet - Heat cycling. Fiberglass & wood expand and contract at different rates. If a wood panel is attached to a fiberglass panel with a thin layer of glass, the joint gets regular stress from the dissimilar materials. Also, if you bridge a gap with fiberglass, kitty hair, etc. The edges often will develop little cracks. This can be seen when large holes (instruments, through fittings, etc. have been filled but not adequately ground out prior to filling with glass. Even if it is done correctly, a "halo" of the hole can show back up. This is why a lot of restorers re glass the entire deck of some boats, to help prevent repaired areas from showing through. On mt Skagit, I cut the transom core 3/4" shy of the top edge and filled the rest with solid fiberglass. The top edge was then ground & filed perfectly flat. Then it was gelcoated. It looked like a factory new transom edge. After a couple years some tiny cracks started to appear where the outer skin meets the top edge. This is a curved transom and it is over 1 1/2" thick.

I have a feeling this hits it right on the nose. I clean the splash pan fairly often because it gets a mist of fuel and oil that sits in the inner edge near the motor, particularly with the motor tilted up all the time with the transom saver. That crack wasn't there until we had a cold snap!

That doesn't make me feel any better...

Frank