Swim Platform Transformation

[ThirdHatt]

That looks FANTASTIC Paul!!!

I got my Slane platform in last week and we fitted it up and drilled the mounting holes in the transom today. We raised it 1 1/2" from factory height mainly to make sure the extra 4" of depth would stay well clear of the wake at all times. It's now just about at the bottom of the aft spray rails.

Here's the fun part: From the factory there is a freshwater tank glassed into the transom on 58YF's which spans the three inner swim platform brackets, so there's no access to through-bolt these three brackets, only the outer two. I was told by Tom and Hatteras that 58YF's had 1/4" metal plate strips glassed in the transom to receive the three middle swim platform bracket bolts. All I had to do was drill 1/2" to 3/4" into the glass, then hit metal. Then drill 3/8" more (to get through the 1/4" plate) and then drill and tap. Simple enough. Problem is, THERE WAS NO METAL PLATES!!! I called Tom Slane back and he was about as surprised as I was. I made sure I drilled right above the original (previously glassed in) holes so if there was a metal strip there I most certainly would have hit it. I re-measured from the center of the transom outward and the holes are right on the mark. I've gotten through the outer layer of glass and into the core (balsa).

Since on the other side of the next layer of glass is my water tank, this is as far as I can go. Tom and I figured the only thing we can do is dig out as much of the balsa as possible through the 5/16" bolt holes with an alan wrench or something and mix up a super strong pot of west system and squirt it in there to fill the void behind the outher transom skin. After it kicks I'll drill and tap for 3/8" fine/machine thread and 5200 those brackets up there.

I'm certainly not thrilled with the idea of no real backing on these bolts, but what choise do I have? Any other ideas short of ripping out the water tank?

 

[Boss Lady]

I would make some stainless brackets that would span the new holes and the old lower holes. That way you would spread the stresses between the two and the old holes should be strong enough since they are factory. I don't think the new holes alone with some goo in them would last very long, especially with a larger platform.

 

[ThirdHatt]

Chris, I had actually thought of doubling the amount of bolts in the manner you suggested. I'm glad you said that. The new Slane brackets do cover the old holes as well, I've just got to drill three more holes in the brackets and then the transom.

I don't know of any other way than to dig out some core and fill the void behind the outer layer of fiberglass than with epoxy with lots of microfibers (or some filler material) to give it as much strength as possible. That will at least double the amount of threads that the bolt will be able to hold on to.

 

[yachtsmanbill]

Hey Byron--- Youll have problems iffen you kiss a dock and also when backing down with that killer marlin on Can you get an ultra sound done to locate any metal reinforcing? You can also use a thermal gun as aluminum will sink heat real quick. you'd need to scan it and lay out some kinda grid to locate the metal.
I would guess a heat gun or nice cold hose water would show the temperature delta. If not, I would consider at the very least some stainless toggle bolts.
Is the outer skin on the tank PART of the transom or is there an air space in there? Can you slip a 1/4 X 4" piece of aluminum flat stock in there? Or can you use the original brackets and make a spacer to raise it?
The pics are of HATT TRICKS brackets and the 53 in IUKA-- I dont know if my extension has metal inlaid, but the bolts were about 4" long. ws

 

[ThirdHatt]

Bill, I don't know anyone with a thermal gun or ultra sound. I do have a stud finder though! I'll try that tomorrow for the heck of it.

I was told that the tank wall was the inner wall of the transom, but at least on the sides of the tank it looks to be about 1" off the inner transom wall. It does me no good because there is hardly room for an arm on top or bottom of the tank and you could NEVER reach behind it at all.

 

[Starman]

Th,

Just saw this.

On Boss lady there is some aluminum bars glassed into the transom. Those areas were blistered really bad, and during the repair is when I saw the aluminum.

First:

I would not rely on just filling with epoxy and additive. I think this is asking for trouble down the road.

If you can determine there is a gap between the tank and the transom, as I expect there is because these boats are production made and the vast majority of add-ons are pre-built then installed.

Once this is determined, I would drill a small ( 1/4 ) hole and gently break through the transom. Then using a pencil or smaller rod, push inward till you feel the tank. This will give you and idea of how much, 9 probably very little ) room you have. I also expect as you go outboard, the tank will be even closer to the transom.

Lets back up just a tad.

Is the tank tabbed in with fiberglass. Like sitting on a sheet of ply ? If so, a sawzall can cut these tabs, and the tank will slide. We did this on Boss Lady with the fuel tanks to make room for the larger exhaust pipes.

Back to the other options if the tank will not move.

I would grind out the transom area and re-glass the areas where the bolts need to go. Additive alone with west system is pretty dang strong, But a few hours more labor will offer better insurance.

That transom is thick. Grind out until you reach the inner side of the fiberglass. Glass in a steel or aluminum plate and fill the area back in with fiberglass.

Now you can drill/tap/ coat with 5200 ( each bolt ) and feel safe and secure.


I hope this all made some sense, as I tried to focus here. I have been on the phone and doing emails since getting home this evening. And this is OK, cause it keeps me outta' trouble. LOL

 

[ThirdHatt]

Where are MY aluminum bars?? The tank is "tabbed" in as you said Paul and honestly as scary as cutting those tabs out and moving the tank sounds to me, the grinding large strips of glass out of the transom somehow sounds less appealing to me. Maybe I'll look to slide the tank around on the plywood shelf tomorrow. If so, I'll have to figure out some way to strap it down good when I'm done.

THANKS EVERYONE!!! Back to the yard in the morning to deal with it, so all this help is GREATLY appreciated!!

 

[SKYCHENEY]

When I made new platform brackets, I used the old holes. But, it was easy for me since I did have the metal plates in there. I don't know if a stud finder would do it. I'm pretty sure they're aluminum and I don't know if those can tell the difference between aluminum and fiberglass. Might be worth a try though. I once got the local fire dept to use there thermal imager when I was looking for some water lines in my concrete floor. You just have to talk to the right people.

 

[Starman]

TH,
the aluminum plates should be where the old holes for the brackets are.

And yes, if the tank is tabbed, 99% chance, just like our fuel tanks, it will slide. I had to use a couple 2X4's for leverage, and we did have fuel in those tanks.

Tabbing back is really easy as well. Just a bit of sanding or grinding to remove any shine/paint ect.....

Some fiberglass and west epoxy .

Once you move the tank. I would clean the interior wall of the transom( sand/gring it smooth ) and you can install a backing plate for those bolts.

 

[ThirdHatt]

Th,

Back to the other options if the tank will not move.

I would grind out the transom area and re-glass the areas where the bolts need to go. Additive alone with west system is pretty dang strong, But a few hours more labor will offer better insurance.

That transom is thick. Grind out until you reach the inner side of the fiberglass. Glass in a steel or aluminum plate and fill the area back in with fiberglass.

Now you can drill/tap/ coat with 5200 ( each bolt ) and feel safe and secure.


I hope this all made some sense, as I tried to focus here. I have been on the phone and doing emails since getting home this evening. And this is OK, cause it keeps me outta' trouble. LOL

Well, I looked hard at the tank first thing this morning and the tank is NOT going to move easily at all. I did what you recommended Paul. I ground down the areas for the bolts and dug out the foam core. Inserted 1/4" aluminum plate (like there was SUPPOSED to be already) and glassed them in.

Tomorrow, I'll drill and tap and feel MUCH better about the job. Another day and some extra work, but it was worth it to do it right. WHEW!

THANKS Paul and others for the thoughts and ideas!

 

[Starman]

Nasty work grinding out that fiberglass , but now you will have comfort knowing that new platform is secure.

You can go ahead and glass it over, then drill and tap TH.

Add some 5200 to those bolts, and plenty around the bracket as well.

Looking forward to the pics when you get done.