One solution for adding a ski pylon

[oldmanram]

Hi Guys, I own a 2007 205 sport and like a lot of you I was unhappy using the center tow hook or the transom tow hooks for tubing and water skiing. They are both positioned too low, and when tubing the line will hit the wake causing a spray for the tubers. (and swimming eye goggles don't look cool enough)
This is the solution I came up with, using an EDDIE Marine ski pylon kit: It is installed in the swim step of my boat and works great. I cut over a foot off the pole after these photos were taken, to minimize deflection, and it just didn't need to be that tall. I can say I MAY take a little more off but at this length deflection is less than 1/2" when pulling a tube. edit: The distance from the swim step to the top of the pole ended up being 24" . This proved to be MORE than enough extra height to keep tubing rope out of the water. I may even go down to 18" or 20" above the deck. Also I have submerged a tube at low speed with no permanent pole deflection.
The black panels you see are 1/4" carbon graphite reinforced composite panel's that are epoxied to the fiberglass to spread the load out. In addition, on the vertical part, where the old ski hook was,I also added a 1/4" Stainless Steel flat bar to further strengthen that area.

Tubes have a lot more load than a skier (load about 600-800lbs) , I saw one post that said a tube can have as much as, or over 2,000lbs of force if it submerges. So couple that with the leverage advantage of this application and you are looking at some serious numbers. Somewhere in the 4,000 to 6,000 lb of momentary force. These forces will rip the average tower to shreds.
It's pretty straightforward the worst part is the prep of the glass, all gelcoat MUST be ground off for a good bond, that took a good 4 hours. I used carbon graphite reinforced composite panels 1/4" thick Use the best stainless hardware you can get when bolting the parts together. And don't forget a little 5200,or silicone on all bolts going thru the glass.
Also I had little room for a drill , so I positioned my plate then used a small Milwaukee right angle drill adapter , photo ,
This setup has one season on it and the pole is still straight up. Grip it and Rip it guys

 

[alldodge]

Nice job on the install
Assuming the top plate is 1/4 steel plate
If you have any issue with cracking it will be the bolt holes.The straight back pulling it should do fine, but the lateral pulling is where mainly the bolt holes are holding the load. I would think about using a 3/4 piece of plywood or coosa board and epoxy.

 

[ahicks]

Nothing but opinion to back my thought, but if that were my install, that pole would be much shorter (1/2?) - to reduce the leverage on the hull and the load on the tube itself. That's me though....

Question being, how high is high enough?

 

[JASinIL2006]

I would not be comfortable using a pylon to pull a tube... a booster ball is pretty good at keeping the tow line out of the water. There’s just too much leverage applied to the pylon mounting point when pulling a tube. Your install is nice and clean, but I’d still be concerned about everything holding up over the long haul. I do hope it works for you, though.

 

[oldmanram]

Thanks for feedback guys,
EDIT: The backing plate is 1/8" Stainless Steel flat bar, not 1/4" as I stated earlier.
Some of us are getting old, just don't remember things as well as we used too.
Here are a couple of UPDATED photo's:.

As you can see the pole has been cut off significantly from the first photo's
It now projects about 24" above the deck

I may cut off an additional 4-6 inches , last year I did notice that when going INTO the wind the tube would get pretty light. And I tow some kids that enjoy going FAST. I remember one time I got it so light it was "sponson walking" (google hydroplane sponson walking video)
And I tow a 3 person tube. Pretty big surface area.
The point is it still may be too high , and lowering it will also reduce the mechanical advantage thus reducing the force on the bolts.
The last photo shows the Forward Lean of the pole , just a touch.