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AZ_Calling
07-18-2006, 07:01 PM
Has anyone ever pulled a skier from the tower. I am to scared to do it. I took a friend out the other night and they wanted to slalom behind the tower. They say they have done it behind other people's boat and it is really easy for them to get out of the water. I just worry about the strength of the tower.

On the same note, I am starting to teach my 5 year old to ski. Do you think it would be easier for him to get up using the tower?

lowdrag
07-18-2006, 11:54 PM
I've pulled people on a wakeboard for the first time that didn't know how to get up and they've really plowed water behind the boat with no problems to the tower. I don't know that I'd have a problem pulling a skier behind it. If I were to do it though, I would make it clear to them not to swing wide and cut really hard like you see the tournament skiers do. I think that the lateral force on the tower from a hard cut would worry me. As for a 5 year old that is learning I don't think you'll have any problems. Bottom line is that it's your boat. If you're not comfortable with it, just lay down the rules. They may not be happy with it, but they're not the ones that shelled out the money on the boat.

Yellowmobius
07-19-2006, 09:53 AM
I would not recommend pulling ANY adult skier off the tower, if they want to tell them to get their own boat.

Pulling a kid is a different story, I think it would be fine off the tower.

Smrtz
07-19-2006, 11:54 AM
Ive done it.. No big deal. there is less resistance from the skier. Or at most you would compare it to edging hard toward the wake on a wakeboard.

TN_Boarder
07-19-2006, 02:32 PM
I was thinking the same thing. I've done it. Are there any manufactures' recommendations not to?

qb12
07-19-2006, 03:08 PM
If you read your manual, it states "do not tow skiers, barefooters" and by doing so it can void your warranty.

Smrtz
07-19-2006, 03:19 PM
I wonder if its the kind of thing where they didnt test the towers with skiers so there is no data as to if it is good or not, so to be on the safe side they just say dont do it... Either way if it can void your warranty then I wont be doing it again!!

Thanks qb!!

JoeTechie
07-19-2006, 07:43 PM
No big deal. there is less resistance from the skier.

HOW ?

Wakeboard = 139cm x 30cm = 4170 cm^2
Ski = 170cm x 10cm = 1700 cm^2

That is 2.5 times the surface area! It is not just the problems of the torque arm while cutting hard that can tilt the boat or put strain on one side, but both the pull against the boat getting from bouy to bouy which is MUCH harder than any wakeboarder can pull, and the real problem is getting the mass out of the water with MUCH less surface area. It is that strain I woud worry about most. MAYBE if they got up on two, then dropped, - but the reason they want to use it is to aid in getting up on one.

I have no tower, but would never let someone test my gel coat because they suck at deep water starts!

-Joe

BensonWdby
07-19-2006, 08:58 PM
I would be willing to guarantee I apply more force to the attachment point of the rope using my 68in ski at 220lb at 32 off / 34mph than any wakeboarder does.

My manual says don't do it - so I don't.

I don't see any benefit to it. I would think it would tend to stand you up to early.

If you are thinking that it might help keep rope from draging while teaching new skiers, you would be better off to start them at 15 off and use the pylon.

My 2 cts
Dave

tarkus70
07-20-2006, 09:44 AM
I am looking for pics of a person I know who towed a skier from a tower. it was not a good thing. A few things it was a factory installed tower and the boat was several hours out of break in service. The skier was about 200 lbs. Oh and the boat Co. did not warranty it. I would never do it. I will post the pics if I can find them.

zabooda
07-20-2006, 10:27 PM
I don't think there is any benefit to skiing or teaching someone to ski from the tower. Skiing your looking for pull while wakeboarding your looking for more lift. I know I could mess up a tower the way I ski. I have to replace ropes each year because of the wear of the rope on the pylon and it's not from abrasion. I pull a couple tubes at times from the tower but there isn't that much lateral pull and most of the shock is from waves. If I started seeing problems with the tower or mounting points pulling tubers would stop real quick. I only do that to keep the ropes out and to match the rope lengths.

JoeTechie
07-21-2006, 01:17 AM
Zabooda - The force of tubes outweighs that of 3 skiers ! There is a reason that tube ropes are so thick. Simple physics, less planing area = more resistance. Multi person tubes amplify this. Sure, when they are skipping along at 25mph or so outside the wake - almost nothing... but when a tube+ rider gets air, then digs into the wake, wow - there is some resistance!

Food for thought,


-J

zabooda
07-22-2006, 02:25 AM
Joe

I agree with the skipping part with tubes and digging in being a problem but to me it is a really big problem as the tower takes a lot of shock that the wakeboarder wouldn't encounter. Unless my calcs are wrong, the planing area of a tube far exceeds the planing area of a ski ( approx. 5 times).

Using numbers from my desk, a ski is 69" x 8" = 552 sq in
a tube is 5' diameter = 30" radius
A= Πr2
A=(3.1416)(30")(30") = 2,827 sq in

JoeTechie
07-22-2006, 12:50 PM
Those numbers would be good for a flat disk, but tubes are not flat. Surface area that touches the water is far less, and they are not flat and do not plane. So is is a dragging force not a planing force, but even if it was, the surface area of a tube that is touching the water at speed is far less than one of a board or ski. And again since none of it is a flat, all it wants to do is remold iteslf, not plane.


-J