Swim platform awash while underway.

Red Raven":14xaxab0 said:
cracker39":14xaxab0 said:
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.

You’re right, of course - but most respondents seemed to be talking about the problems with the wet swim platform occurring at cruising speeds around 7 knots. I can assure you that trying to make headway against a 5 knot current, with 85 hp, was something to be avoided if you had a choice! Having the mindset of an old sailor may color my opinions somewhat.
 
Perhaps adding a spacer between swim platform and brackets would solve the problem, which could raise it an inch or two. Along with perhaps relocating some weight forward.

I would also compare the platform mount height with other boats of the same brand and see if perhaps it was in fact attached too low. Even so this is a production boat, every once so often an installer may have made a mistake.
I was under the impression that all mounts and cutouts are done with templates and found it not to be true or perhaps not always applied. When I stated to disassemble some parts and panels I found some of the cutouts not as smooth as I would expect them if a template for a router was used. Pretty sure this is how all boats in the industry are build and unless you utilize expensive robotic assembly machines to handle cutouts and holes, precision won't change much.
 
cracker39":11r7ue9e said:
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!

I agree and disagree ! It doesn't take 200hp + to push a 29 hull to 7 Kts. It takes very little HP. It takes 200hp + to push that semi-displacement hull 18 Kts. The Ranger and Cutwater design is trying to fit several different boating needs. The Prairie Pocket Trawler is a comfortable slow efficient cruising Trawler. Try to go fast with your 29 Prairie it isn't going to happen. Throw the throttle down and get a couple more MPH over hull speed throw a big wake and waste a lot of fuel. The Rangers and Cutwaters would do the same thing, most likely worse then your Prairie with 84 hp. Thats why they have 200+ HP to get it past that big wake, big hole ,speed and get it up on top of the water. It takes a lot of horse power to do that.
Could their design be better? Probably, adding aft flotation hull lift in their design like some of their competitors Nordic and Helmsman, but its a trade off. This post is about the swim platform and what the performance loss is if any when the platform is dragging and submerged at slow to mid cruising speeds. Some Tug and Cutwater owners feel that it is a performance, economy , and poor design issue and other owners and the factory feel that design doesn't effect performance and economy. We can debate this subject about who is right and who is wrong and will probably never know. I'm not taking the platform off my Cutwater to see how the boat performs with out it. I don't think that Ranger /Cutwater is going to take the platform off one of their boats and do performance test and report the results its not in their best interest. I'm going to take it as this is the design and use the boat at speeds that the platform doesn't submerge and drag and when it does.....
Brian Brown
Cutwter26
PORT-A-GEE
 
Well said Port-a-Gee!
 
AS mentioned in my earlier post.....I plan on living with it. My 2017 28 CW is still a beautiful boat and is fun to drive ,with all the electronic goodies ,turns heads where ever it goes!
I just ignore the swim platform awash issue. Might cost a few dollars in extra diesel but compared to the $200,000 the boat cost, not a big concern!
 
As "Sequel", "Baz", "Ken Boyd", "Levitation" and "Knotflying" have said on this forum in other posts, "Boating is all about compromises." I fully agree with that sentiment!

Ranger Tugs have many compromises:
1. List to port on R25/R27 with the generator, but isn't that generator nice when you really need one.
2. Thrusters that are way too difficult to access for an item that breaks too frequently and too weak in a strong wind or strong current, but they are marvelous when working.
3. Glare off the bow rails with sun and/or the spotlight, but the rails are very functional and look great in profile.
4. Semi-displacement hull that needs lots of horsepower to semi-plane, but its really great to go fairly fast when you really need to with strong currents or approaching nightfall or bad weather.
5. A cabin that acts like a sail in strong wind to push the boat around, but it sure is an eye-catcher and great to get inside in bad weather or too much sun. I get great comments or thumbs-up everywhere I go on every outing.
6. etc. etc. etc.

I think the swim platform awash at times is one of those compromises, but many people love the functionality of the swim platform.

Just today, in being out for a day cruise that lasted about 3-1/2 hours, we received waves and thumbs-up from 3 different on-looking boaters, from one kayaker and from a guy sitting on a dock as we passed by. Upon docking for dinner at Doc Ford's, a deckhand on a 50' Sport Fisher ran over to comment on our R31 about how much he loved it. Then voluntarily he went to his boat and came back with a bottle of Rust Aid to clean up some rust stains from the stanchions on our R31 swim platform. He did all this because he was so excited about seeing the boat. I was a bit surprised that he was so concerned about how my boat looked with the stains. When he was done, the stains were completely gone.
 
Dale777":1n3cmgo3 said:
..."Boating is all about compromises." I fully agree with that sentiment!....
There's a difference in compromise, like a semi-displacement hull, and just poor design, like a swim step that drags in the wake. Everybody makes design faux pas. Continuing to produce hundreds of copies once a problem is identified is a bit odd. Consider how many iterations the mast/radar mount went through in a relatively short time in a diligent effort to correct a design issue. So what gives with the step? After all the original design didn't exhibit the same performance sapping characteristics.

I submit that the design is very intentional as-is and is for environmental reasons. Ranger is simply trying to force more owners to operate in the displacement regime to minimize fuel consumption/emissions. Someone in Ranger management must have interned as a capitol hill staffer.
 
The factory solved the problem (if there was a problem) with the R25SC.......discontinued production. 😉

Seriously, I’m happy with my compromise boat.
 
Any chance of retro fitting swim platform successfully used on the classic model onto an SC model? Just a thought
KH
 
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