Building a Custom Removable Swim Platform?

[PitchFork]

I am thinking of building a custom removable swim platform. I work for a Metal shop and have access to Laser Cutters, Welders, Powder Paint Line, and many other machines. The reason I want it to be removable is I keep the boat in my garage during the spring/summer months and with traditional swim platforms they are not removable and just cost way too much.

My question is about the mounting the plates on the back of the boat. In the attached picture I have two rectangles of where I would put the mounting plates made from 1/4" 5052 Aluminum. The plates would be mounted with 6 screws for each plate. 3 screws per side of each plate with a rubber backing behind the plates to protect the hulls finish. Each plate would then hopefully support the weight of the swim platform and persons on it.

My question is this area of the rectangles in the picture able to support the weights up to 400 pounds on it? I am also scared to drill into this area and mess it up. Does anyone have any experience or recommendations on this project? Any different ways to attach swim platform so that it can be removable?

The swim platform size I am thinking of is length of the back of the boat from tie down ring to tie down ring and extend out 2 feet. The platform itself would be made out of 3/16" 5052 Aluminum with a rubber pad / mat installed on top of it from Overtons.

 

[mike343]

Re: Building a Custom Removable Swim Platform?

The question you are asking is whether six(?) self-tapping (maybe 1/4 or 3/8) screws into the transom would support the load. It is obvious that you can't get to the inside so you can use bolts. My guess is yes, let's see what others think.

If you decide to do it seal the holes with good stuff (5200?) or the transom will be subject to water intrusion.

 

[haulnazz15]

Re: Building a Custom Removable Swim Platform?

While I think the alluminum stock would support the weight, you may want to add two smaller ones for the outsides just to help with the flex of the platform. In either case, I think it's a neat idea, but how often/why would you find reason to remove the swim platform. You are almost building in functionality that doesn't get used.

I know the Cobalt 262/272's from the 90's used to have a swim platform that folded up into the transom, but I don't know how it worked (i would assume electronic acuators) and how often the owners used it.

 

[smartwork]

Re: Building a Custom Removable Swim Platform?

PF -

Wow, you must have been reading my mind over the last couple days. I've been staring at the back of our boat thinking about how a platform could be made and removed or folded up (for storage in a garage that doesn't accommodate the additional length to the boat). I've seen designs ranging from teak, fiberglass, mahogany, and even one I think here on the forums that used tough deck material used for homes. Like you, I've been looking at the attachment points for the deck, but would prefer to use bolts with nuts on the inside of the hull, but that leaves me estimating the angle that the supports can be at to support the deck while being positioned on the transom at a point where I can access the inside (to attach the nuts).

I'll be interested to see the feedback here.

 

[PitchFork]

Re: Building a Custom Removable Swim Platform?

While I think the alluminum stock would support the weight, you may want to add two smaller ones for the outsides just to help with the flex of the platform. In either case, I think it's a neat idea, but how often/why would you find reason to remove the swim platform. You are almost building in functionality that doesn't get used.

I use my boat in the summer almost every other day and since I live in a Subdivision I cannot keep the boat outside. So I would be removing it every time I put it back into the garage.

I really like the idea of being able to fold it up. I will have to think about that one for a few days and run be our Engineers here at work.

 

[75TowerOfPower]

Re: Building a Custom Removable Swim Platform?

How does the boat fit the outdrive being down and out there?

I would go ahead and make it hinge and then have your support poles come down and pin on to those mounts on the lower part of the transom. I think this would be your best idea. Use some SS piano hinges for the top mounting point and then have a sleeve that goes over a solid stud welded to you mounting plates on the transom and pin it there. So you don't need any tools to remove it.

 

[PitchFork]

Re: Building a Custom Removable Swim Platform?

How does the boat fit the outdrive being down and out there?

I would go ahead and make it hinge and then have your support poles come down and pin on to those mounts on the lower part of the transom. I think this would be your best idea. Use some SS piano hinges for the top mounting point and then have a sleeve that goes over a solid stud welded to you mounting plates on the transom and pin it there. So you don't need any tools to remove it.

That has me really thinking now. I might be able to put hinges on the platform and have it fold down as I can and do put the outdrive all the way down when it is in the garage. I will cut out a template out of cardboard and see if that would be clearance around it when the boat is in the garage.

Keep the ideas coming they are helping.

Many Thanks

 

[smartwork]

Re: Building a Custom Removable Swim Platform?

One hurdle resulting from hinging the transom side of the deck may surface if your transom is curved. Hinging a curved surface may cause it to bind as the deck moves upward. Maybe a 2-piece deck where there is a strip of say... maybe 5" or so that is the entire width of the platform. This strip mounts permanently to the transom and conforms to the transom's curve for a nice custom look. The other side of the strip (facing away from the boat) would have a straight edge that you can then hinge the remaining portion of the platform to. This way, the second section would flip up based on a straight hinge with no binding. Hopefully, that made sense.

 

[PitchFork]

Re: Building a Custom Removable Swim Platform?

Good point on the binding part. That having the first 5" permanent means I could attach it permanently and the final 19" of the platform could be on a hinge with bimini type poles to the transom to support the platform.

Thanks

 

[dustedwatts]

Re: Building a Custom Removable Swim Platform?

DID you finish a swim platform? I want to build one for my boat... can u post pics?

 

[Stachi]

Re: Building a Custom Removable Swim Platform?

I am thinking of building a custom removable swim platform. I work for a Metal shop and have access to Laser Cutters, Welders, Powder Paint Line, and many other machines. The reason I want it to be removable is I keep the boat in my garage during the spring/summer months and with traditional swim platforms they are not removable and just cost way too much.

My question is about the mounting the plates on the back of the boat. In the attached picture I have two rectangles of where I would put the mounting plates made from 1/4" 5052 Aluminum. The plates would be mounted with 6 screws for each plate. 3 screws per side of each plate with a rubber backing behind the plates to protect the hulls finish. Each plate would then hopefully support the weight of the swim platform and persons on it.

My question is this area of the rectangles in the picture able to support the weights up to 400 pounds on it? I am also scared to drill into this area and mess it up. Does anyone have any experience or recommendations on this project? Any different ways to attach swim platform so that it can be removable?

The swim platform size I am thinking of is length of the back of the boat from tie down ring to tie down ring and extend out 2 feet. The platform itself would be made out of 3/16" 5052 Aluminum with a rubber pad / mat installed on top of it from Overtons.

I'm wondering if you increased the size of the pads...(rectangles) by a lot ... and try some sort of double sided automobile moulding tape to secure the pads to the hull...then you won't need to go thru the hull to attach the pads. fabricate a Q-D on the pads to recieve the swim platform....just a thought...