Installing a swim platform?

[fourwinnsdook]

Ok, i have an 86 four winns that i just had repainted. Now i need to put a swim platform on it. It didn't have one before. I bought the platform, and the brackets. it's a large one so it's crucial that it's level when the boat is in the water. How do i know where to put it? Ther's no water line on the boat cause it just got painted, and i don't know how to non-permenantly mark the hull while it's in the water without the marks washing off before i wash them off. The transom is not 90*. it has a pitch. Please help. I was thinking about leveling the floor, but i don't even know if it's level when it's in the water. What do you guys think?

 

[Molaker]

Re: Installing a swim platform?

I can't help you with the platform position, but I might be able to help with marking the waterline. Go to Wally World sewing dept. or some other sewing shop and look for fabric marking grease or wax pencils. You might even find grease pens at an office supply. Most grease pen marks will wipe off, but won't just wash off without an effort.

 

[Zetman]

Re: Installing a swim platform?

I did the same project you are trying to do. Getting the water line is important and using the grease pencil is the best way to mark it. First is your boat an I/O or inboard? You are going to want the deck atleast a couple of inches above the water line. It can go higher, but, you might need someone to stand on the back to bring it closer to the water. If you have an outdrive be sure to check in the highest postion before installing the deck(moving parts,steering,gas hoses,etc.) My transom was not 90 degrees also. I had to take my boat down to a metal fab shop(look in yellow pages) this guy came out with some measuring tools and made plans for brackets for my deck. It cost me $150, but I had them made in stainless 2" boxed tubes so it would support my fat but when out of the water.** If you use stainless have the shop drill the mounting holes in the brackets for you.** If you can take some pictures. Hope this helps get you started.
Zet

 

[fourwinnsdook]

Re: Installing a swim platform?

Yea, thanks. i'm going to get the measurements this weekend. It's an I/O, but the platform has the cut out for it so it should clear ok. i know where it needs to sit hight wise, my only problem was getting it dead level with the water line.

 

[Zetman]

Re: Installing a swim platform?

You don't need it level with the water line. Make it equal on the boat itself. Boats in water are not level anyways. Measure down from a fixed area on the boat, and keep it equal on both sides..does this make sense?

 

[salty87]

Re: Installing a swim platform?

yep, the waterline will change depending on weight and where the weight is. if everyone is at the back getting in or out, it will change a good bit.

 

[WaterWitch2]

Re: Installing a swim platform?

You don't need it level with the water line. Make it equal on the boat itself. Boats in water are not level anyways. Measure down from a fixed area on the boat, and keep it equal on both sides..does this make sense?

That's what I was going to say.

 

[fourwinnsdook]

Re: Installing a swim platform?

Yea, i'm not worried about mounting it level on the boat, i'm talking about making the platform level with the water I.E. i don't want the back of the platform pointing downward while the part attatched to the transom is not. Ya know?

 

[OhWellcraft]

Re: Installing a swim platform?

One thing you might want to try if you want it "level" is to take a framing square and hold it onto the transom. Then have a helper hold a 2' level on the leg of the square not against the transom then pick the level up until level and measure how much you need to add to make it level. Use the longer leg to set level on it will be marked so you can come out however deep you platform is and that is where you take the measurement. On most I have seen they are a bit lower at the water edge to help get the water off. But if it is a wood one with the slots in it you would be fine to mount level. Use a GOOD sealant when going through transom with brackets/bolts also might not be a bad idea to use backing plates on any mounts that will pull out. Ones that push in ie bottom brackets are fine without backers. One other thing you might try is to use a piece of ridgid foam or cardboard taped on at your desired height and step back and look at it from all angles. Make sure you like the looks of it and that it flows with the boat lines before you hard mount it. Stainless is very hard to deal with as far as cutting drilling etc. Around here most metal shops aren't open on Sat. so if it is a weekend project might want to check into that as well. good luck.

 

[Zetman]

Re: Installing a swim platform?

Now I know what you mean. With a 90* transom the swimdeck would point towards the water. You are going to have to make yourself some wedges to offset the transom angle. The guy at the fab shop had a protractor to get my precise angle to make the brackets. If you don't want to go this route hand making a wedge would be my next step.

 

[fourwinnsdook]

Re: Installing a swim platform?

The transom is not 90*, and the swim platform has to be level when the boat is in the water. So what i'm asking is how do i know (with the boat on the trailer) where to mount the platform without putting it in the water first and making marks of where the water level is on the side of the boat. theoretically shouldn't the floor of the boat be level when the boat is in the water? So all i should have to do is make the floor level and put the platform accordingly. I know the angles will change with the weight in the boat, i just want to do it right.

 

[OhWellcraft]

Re: Installing a swim platform?

On the trailer it is kind of a guessing game. I think the only way to know for sure would be to put it in the water. Take the framing square with you like I mentioned and see where it (the water) comes on it and measure from there. By using the square you will have a set point from which you can base everything off of, you could also get your exact water line at that time. If you want it perfect this seems to be the most exacting way that I can think of. I dont think your floor is exactly level while in the water otherwise any surface water that got in there from swimmers etc would just sit and not drain back to where it should. Might be worth a try if you want it perfect. Or you could take the grease pencil and mark the water line at the bow, midship, and stern. Then once it is on the trailer you could run a string so that it touches all three marks and extends past the transom to give you a reference point for the water edge of the swim deck. Don't know if any of this will help, but sometimes the more thoughts the better.

 

[salty87]

Re: Installing a swim platform?

The transom is not 90*, and the swim platform has to be level when the boat is in the water.

i understand you want it done right. but, the boat won't be level on the water very often. you'll roll back n forth and pitch like always. more people sitting on the platform will change the pitch of the boat. more people on one side...you get it. i'd get it close where you can be happy and get it done. my biggest concern would be too high and requiring a ladder.

 

[Zetman]

Re: Installing a swim platform?

put the swimdeck at 90 degrees with the back of the boat. If your transom is 80 degrees make the brackets so your swim deck sits at 90 degrees to the back of the boat. It will look good and work fine.. Zet

 

[Sorrento 25]

Re: Installing a swim platform?

2 waterline marks 2' apart on the side of the hull near the transom will allow you to tape on a yardstick and create a (greater than 90 degree) template of the angle between the transom and the waterline. Then use that to mount your swim platform.

It will look like it is angled up in the back when sitting on the trailer though. Mine is fairly parallel with the chine/rubrail, and thus angled down slightly in the back compared to the waterline in the water but it is not a problem at all and encourages some drainage.

 

[fourwinnsdook]

Re: Installing a swim platform?

Ok, i put it on yesterday, looks pretty good.The platform came off of a chapparal, and i put it on a Four winns. I used the same brackets. It may need to come up a hair in the back. but i can adjust the angle brackets atleast an inch without having to move the main brackets. I haven't put it in the water yet, so i guees we'll see this weekend if it's good or not. I know on my OMC the logo on the outtdrive sticks out of the water so i know the platform is going to be atleast 3" out of the water when not moving. that should be pretty good. A friend of mine has a Malibu and his is actually under water about 1" when he's idling. I saw an old Baja last weekdn that had the swim platform like 1' out of the water with no ladder... Looked pretty dumb to me.I think he had to raise it up for his thru hull.

 

[Zetman]

Re: Installing a swim platform?

Cool..take some pictures let us see..Zet