Swim platform awash while underway.

[Don Cardinal]

I wonder how much extra cantilevered weight is in the swim step if it is saturated inside with water? Of course once it is awash it becomes more or less neutralized. Just a thought.
Don

 

[mrrlc]

It would be of interest on this issue to see some, at dock, measurements of the swim platform and compare between R25 owners. Possibly these:
Distance from top, center, farthest aft, point of swim platform to water.
Distance from top, center, next to hull, point of swim platform to top of rub rail.

 

[baz]

Mike:

It should alarm RT that many owners here are having this unwanted swim platform awash issue. Just what is the cause I wonder ?

I realize that, but assuming all of the boats are built the same in each model, I am just thinking that there may be excessive weight in the stern area and perhaps not enough trim tab. I do not have a generator and I keep the cockpit relatively clear with weight distributed evenly so I eliminate ant listing. I am sure that adding a genset, full holding tank and a dingy on the platform will make a difference.

On my previous 2010 R-25 (Classic) I had a Portland Pudgy (~150 lbs), Two large Red buoys and 300' of 1/2" line coiled onto a water hose reel on the swim platform. Add to this a ton of gear stuffed into the transom seat's locker and the two side cockpit lockers. The 30 gallon holding tank is also wedged up close to the transom so when this is full this 30 gallons quite likely adds another 250 lbs to the stern of the boat.

With all the above my R-25's swim platform never was seen to be awash.... yes it got wet at times but never was submerged as indicated by the OP's photo image.

 

[BB marine]

On my previous 2010 R-25 (Classic) I had a Portland Pudgy (~150 lbs), Two large Red buoys and 300' of 1/2" line coiled onto a water hose reel on the swim platform. Add to this a ton of gear stuffed into the transom seat's locker and the two side cockpit lockers. The 30 gallon holding tank is also wedged up close to the transom so when this is full this 30 gallons quite likely adds another 250 lbs to the stern of the boat.

With all the above my R-25's swim platform never was seen to be awash.... yes it got wet at times but never was submerged as indicated by the OP's photo image.

The older Ranger Tugs had a flat Starboard Platform with no lip. The newer Ranger and Cutwaters have a molded fiberglass platform with a lip. On my Cutwater what I have noticed, as I go above Hull speed the water starts to trap under the platform. The prop wash gets caught under the platform causing a slight drag and turbulence . Most of the water coming over my platform is thru the air cutouts between the transom and the platform.This happens between 1850 and 2800 Rpm. I watch rpm more then speed because the speed doesn't change much in this RPM range I just push more water. The trim tabs on my boat don't react or start to correct this until 2850 but then the rooster tail ( if you want to call it that) starts hitting in the lip of the platform and makes a very dirty wake. Any rpm above this the wake cleans up and the platform is out of the water. Any thing under 1850 there are no issues either. My best fuel economy cruise is 1875 to 1950rpm 7.50 mph there is a lot of turbulence from the platform at this speed. There is water running over the platform. I have looked at this many times and feel it is causing drag. If the bottom of the platform was flat with no lip it would help or if the platform were higher it would help.
I agree it is not a safety issue. Just a characteristic of the design.
Brian Brown
Cutwater 26
PORT-A-GEE

 

[stwendl]

Are you noticing the his wash in fresh or saltwater? In saltwater you get more buoyancy and the boat will be higher up.

 

[LAKERtoo]

.. is the lip a feature to give strength or stiffness to the platform ? if so, would removing it and putting a stainless stiffener on the topside help with the turbulence ? .. just a thought .. Rob

 

[baz]

Then of course we should add the weight of the person standing at the transom looking at the swim step be awash. :lol:

 

[knotflying]

I did see that at 7.8 KTS the trim tabs were not deployed. Once I am at that speed I am using trim tabs to lower the bow. This may be a matter of trim tab use. My bow would be way too high at 7.8 KTS and no tabs.

 

[snydzy]

Just to weigh in,...I own an R25sc, and I can get the swim platform to go awash with a bow up attitude, no trim tabs activated. If you think about it, the diesel R27 and R25sc are identical aft the cabin, and that being said, it is a given, due to the longer length of the R27, that it would have a more forward center of gravity. I would think that the shorter R25sc can achieve a higher bow up attitude, making trim tab use more essential. Add a generator in the cockpit, even more so.
I actually use the swim platform “wash” to quick check the boats bow attitude. I can’t speak for the R25 classic as motor placement and center of gravity are different.
As to salt water, it’s about 2.5% more buoyant than fresh, so a 10,000 lb boat in fresh water would be about 250 lbs “heavier”.

 

[Boatagain]

The first ride I ever had on a Ranger Tug was the sea trial of the brand new ‘14 R25SC I eventually bought. There were three of us onboard and perhaps half a tank of fuel. The water tank was empty and there was nothing else aboard except for the factory supplied items. With the salesman at the helm, we headed out into Chesapeake Bay (brackish water), my wife in the cabin and me sitting in the cockpit transom seat. As we picked up speed, I looked over my shoulder and was shocked to see the swim platform completely submerged and creating its own distinct wake. I asked the salesman about this...he just shrugged.

You don’t have to be a naval architect or even an experienced boater to understand that the extra drag created is significant. IMO It’s a design flaw that should be corrected.

 

[William Thomas]

All the above chatter has been directed at Tugs.........as myself and another owner mentioned earlier in this thread , happens on CW 28's as well. I just live with it.

 

[pleeson]

I brought this up shortly after buying our C28. I was ignored. While never submerged, the spray, wash, and drag, created by this design speakers poorly to the designers attention to detail. Boats in this class should not have sore points after several years of consumer testing! I think the platform should be raised until almost flush with the cockpit door sill, with more/larger cut-outs along the hull to ensure the cockpit doesn't flood. If necessary the cockpit door sill should be raised. The lower lip and stainless support brackets should also be eliminated and exchanged for a sealed flotation style platform with the front side thicker and tapering smoothly to a thinner aft end. This triangular cross section and smooth sealed underside would offer little drag, and act as flotation and a wake deflector to assist the trim tabs, and resist the tendency of the swim platform to sink and grab the wake coming past the stern of the boat. It is ridiculous that there are so many portions of the RPM curve that we have to avoid for drag, spray, and performance issues, and the corrosion of the support bars and associated nuts and bolts protruding beneath the existing platform design is a hassle I don't need. Treat the thing like a hull extension pod for an outboard, and deal with this sore point once and for all.

 

[NorthernFocus]

Yet another aspect of the "classic" model that is superior to newer versions 😀

 

[BB marine]

Yet another aspect of the "classic" model that is superior to newer versions 😀

Normally when a manufacturer makes changes to production models the changes are for the better. I would say that the platform is an improvement to the original 25 classic if you spend most of your time at the dock or at anchor. It is a very nice design and looks great. The down side to this very nice looking platform is it affects cruising performance at about 25% of my rpm range. Above or below that range it doesn't cause issues other than some spray at higher speeds in certain sea conditions. It hasn't stopped me from using the boat and I have learned what adjustments need to be made according to sea condition and speed. My biggest concern is the moisture presence in the wood core after one season of use. Last spring I installed weaver mounts on the platform. When I drilled the mounting holes I noticed quite a bit of moisture in the wood filings. I inspected the wood thru the holes drilled and it wasn't rotten at all just wet. I resealed all the factory installed fasteners most were sealed good a couple not so good but they were a distance away from where I had drilled the holes. I'm not sure how this moisture is getting in there. I do believe there is a lot of water pressure under the platform when it is dragging in the water. Has any one else noticed moisture in the wood core of their platforms and if so figured out where it is coming from ?
Brian Brown
Cutwater 26
PORT-A-GEE

 

[NorthernFocus]

Normally when a manufacturer makes changes to production models the changes are for the better...

One would hope. However economics likely play a role as well. The original swim step design was manufactured out of Starboard material(expensive) and involved a lot of cutting, routing, fastening(i.e. expensive labor). The newer steps are made out of much less expensive material and (once the molds are made) a lot less labor. Faster, easier, esthetically more pleasing (IMO) and, oh yes, cheaper.

Unfortunately is seems to be a slightly flawed design. Ironically since it is cored construction, the lip that is causing all of this discussion is likely overkill from a structural standpoint.

PS, my previous post was made tongue in cheek 😉

 

[William Thomas]

So what's the fix...at least for the CW's?

Just go faster all the time???

 

[NorthernFocus]

So what's the fix...?

A side grinder is faster but a sawzall or jigsaw makes a lot less mess 😉

 

[captstu]

My 2010 R25 had trim concerns for the first few years I owned (adopted) her. Last week I need to replace an aging thruster battery and installed the new battery forward under the buhk and above the thruster compartment.

The results were outstanding. The boat planes (as much as a Ranger planes) smoother and I no longer have to stand up to see over the raised bow! I estimate about a 2" improvement in the bow lift.

Better still, the minimum planing speed dropped substantially and the maximum WOT speed rose over a knot.

The RPM required to maintain my comfortable hi cruise of 13.5 knots dropped a few hundred RPM.

I plan to continue to move load from the stern to the bow - obviously lifting the swim platform and the dinghy I carry on Weaver davits on the platform.

I also relocated the two house batteries to the side opposite the generator to further balance the trim.

Seemed better and cheaper than getting trim tab extensions, I run at just over 1/2 tab when we are lightly loaded.

 

[cracker39]

It’s hard for me to understand why you need 200 plus horsepower to push a 29’ semi-displacement hull to 7 knots when I could cruise all day long in my 29’ Prairie trawler at 7 knots using a Perkins 4-236 with 84 hp. In addition, the Prairie displaced about 14,000 lbs, as it was heavily built, with an 11’-9” beam and a 2’-9” draft. The Prairie ran dead flat, with respect to trim, producing virtually no wake, while the little Perkins brought it to hull speed at about 1900 rpm. Pushing the rpm higher had little effect on speed, however it did cause the hull to start digging a hole, with the expected wake roll building behind. My thinking is that the semi-displacement Ranger hull lacks sufficient flotation aft to avoid rotating about its’ center of flotation - unless counter-balanced by weight forward, or offset by the trim tabs. Too, the somewhat aft placement of the Rangers’ larger and heavier diesel could likely use up a lot of the displacement that would otherwise aid in keeping the stern from sinking when power is applied. This is probably the penalty you pay for having a trailerable boat - but I still don’t understand the need for so many horses!

 

[Red Raven]

It’s hard for me to understand why you need 200 plus horsepower to push a 29’ semi-displacement hull to 7 knots when I could cruise all day long in my 29’ Prairie trawler at 7 knots using a Perkins 4-236 with 84 hp.

If 7 knots was the top speed for a R29 of course it wouldn’t need anywhere near 200hp. However, a top speed of 18kts does.