Turn islands or not?

[eleeski]

@ral Just like the ripples from a pebble dissipate as they move away from where you tossed it in the water, the rollers from a turning boat will fade to insignificance by the time they get to the course.

 

Wait, I've spun a powerturn at 1 ball, picked up the skier quickly and had rollers at the end of the course - how is that different? The primary differences are in the diameter of the turn, the energy imparted to the roller and the aim of that roller. The inside roller (of a turn at the end of the lake) is moving against the boat's motion in a tighter radius with a shorter time focused straight down the lake. It moves with less speed and energy. Thus it will have a longer time to dissipate from a less intense start with larger dispersion angles. The outside wake gets thrown at the shoreline and loses lots of energy and directional focus upon reflection. Nothing like a mid course spin.

 

The propwash rollers from a startup which aims at the course (needed when an island is present) and are closer to the course will be more significant. Additionally, the wakes generated by the skier have a cross course component and as straight line waves they will dissipate less so will dwarf any end of lake effects. And @MS 's kids playing and splashing might kick up a bigger roller than what comes out of a turn. We don't really notice these things - they may be there but they are insignificant.

 

Reflected boat rollers are the major component of moving water. A narrow lake will clear these faster. Care with docks and parked boats will minimize weird reflections. Attention to the slope is very important. These effects are orders of magnitude greater than spin rollers.

 

With 2000 feet, why not drop at the far end and start straight in? No rollers at all with that boat path option.

 

My lakes are under 2000 feet long. We have no problem with setdowns that give a straight in run to the course. We dogleg our pullouts a bit. As trickers too, we often spin at the ends and never see moving water in the middle of the lake coming from the ends. Slalom skiers who simulate an island path never complain about turn rollers. The reality of my experience with island less lakes is that turn rollers are not noticeable in a real world lake.

 

Eric

 

 

 

 

[ral]

@eleeski , thanks!!!

[MISkier]

@eleeski, your explanation provided examples on how rollers may dissipate on their own or how other actions in and out of the course may produce more rollers than a boat spinning at one end without an island. I agreed with those observations. But, you did not explain how islands were "useless" in dissipating rollers from a spin.

 

For the record, I don't use islands regularly and steer to the side of them in lakes that allow it. There is only one lake in Michigan with islands (and you must use them) and I haven't skied there in 8 years. However, I did want to understand how you thought an island would be ineffective at blocking the rollers created inside the turn during a spin. It just seemed to me that it would act as a barrier for that specific type of roller and I was curious why you said it wouldn't.

[MISkier]

Correction: there are 2 other lakes with islands, but those aren't clubs or sites open to the general skier community. They are very, very private.

[ral]

@MISkier, what path do you follow when not using islands?

[The_MS]

Turn islands give you more time to drain water, wipe the eyes and get set.

[MISkier]

@ral, if there are islands that are offset enough and with enough room to one side, we bypass the island on that wide side and turn behind the island to set down. Typically the right side, as you are leaving the course and the 55s and looking at the island, is the side that will be wider. In that case, you will pass the island with the passenger side of the boat facing the island and turn left behind the island when you set down with the skier pulling out to the driver's side to settle/sink into the water.

 

If there are no islands, we tend to curve the boat after the 55s and have the skier pull to the driver's side of the boat to set them down either slightly to the left of the course centerline or slightly to the right of course centerline (depending on the shape of the lake end). I think having them set down close to the turn buoy line is probably far enough off of centerline.

 

When pulling up, we angle the boat slightly to one shore or the other (away from the skier toward the opposite side of the course from where they are set down) to avoid accelerating while pointed straight downcourse. This reduces downcourse bow rollers created at acceleration and initial planing. Upon planing, we immediately re-align with the course centerline well before the 55s.

 

In all cases, we idle around the skier with the skier to the driver's side of the boat and align ourselves for the next pullup and pass.

[eleeski]

@MS Don't pee (drain water?) in my lake! No IPAs before skiing for you.

 

@ral Some prefer to simulate having an island in my island less lakes. Like @MISkier we try not to aim propwash straight down the lake at the start and try to put a little hook in the boat path to minimize the aim of the inside roller deep in the turn. With a tolerably experienced driver it works quite well.

 

You do get to like going straight in pretty quickly. No nasty distractions like surviving the spin around the island. Just focus on the course and go.

 

Eric

[Than_Bogan]

@MS If you never ski turn islands, it's more like "death grip the handle." I don't think there is a turn island in all of New England, so I find them pretty distracting.

[The_MS]

We got lots of room to maneuver. I dont mind straight set ups but some of them tend to rush the skier a bit.

[jdarwin]

If 2150 or longer, not needed. And over time, the maintenance of them becomes an issue. I'm 2150' straight in. I've had a few minor complaints over the years but considering most of the scores, it's not an issue.

[Chef23]

We ski plenty of lakes shorter than 2150 where we go straight in without islands. It can be a little quick but you get used to it.

[MISkier]

I've skied 1750' straight in. It's quick, but very doable. Most of the other lakes in Michigan are less than 2000' and go straight in. But, we are not at any significant altitude (600-900 feet).

 

On another lake, it was just over 1600' straight in. You are pulling out at the 55s at the same time you are still finishing planing. Too short. And, they run a Malibu LX that is lightning quick there.

[ral]

 

[6balls]

I'm fine either way. If my site plan determined that I had to go short on lake length, I'd put 'em in there. If enough length I'd go without the extra hassle of putting them in and any maintenance they may require.

People talk of this hole shot roller on straight in approaches...must be far pickier than me. If that makes me miss a pass anytime soon I'll just let y'all know.

[MISkier]

@6balls, I agree with you that I haven't worried about hole shot rollers for me. But, as a rated driver, I position the boat to try to eliminate them for my skiers to ensure that even a perception (by those who do care) does not diminish their concentration or related performance and enjoyment.

[buoyboy1]

I have islands on my lake and I spend 75% of my lake time trying to maintain them. Erosion and muskrats are the issues I have. You should rip rap them. The boat wakes really erode the edges no matter the extent of shoreline vegetation. Use rip rap down 3 feet minimum. Trust me the added cost of rip rap now using heavy equipment will save you hours of time placing rip rap later on using a Jon boat once the lake is full. Place the top of the island 12" maximum above the lake water level or muskrats will turn it into a hotel and cave-ins will occur. I set the top of my islands about 4 feet above full pond and there is just too much room for them to burrow above the water level. I tried to use 6' chain link fence (staked on the banks) just above and mostly below the water level but they still borrow under the fencing. I do like the islands for eliminating rollers and to give a little more set up time just wish I had set the top much closer to the water level.

[The_MS]

Our islands are constructed of 2-4 inch river stones for the base and it is now covered with larger rocks. We do have the opportunity to drive out there in Jan/Feb so maint is pretty easy. Since adding the larger rocks on top, we haven't had to do much at all.

[Marco]

I don't trust our ice to drive a heavy vehicle on, so we sled the rip rap that we put on most recently. For convenience, we used 60# bags of redi-mix concrete, and left them in the bags. It created bag shaped concrete chunks that seem to be working well over the past several years.

[thompjs]

Use Geotextile fabric under the bags or rip rap. Send a PM if you want some pics of it.