Mounting RIB on Swim Platform

[Bobby P.]

I have:

2017 31 CB with swim platform stanchions
2017 290 Rib (9'6", I believe)
Weaver davit grips (already attached to RIB)
4" up and out mounts with quick release brackets (Thank you Matt Murphy!)
2 Adjustable standoff brackets.

Couple quick questions for anyone who has DIY mounted these or has general info:

1. Who makes the FML (Ranger) RIBs? Is it zodiac?

2. Should I center the davits on the swim platform or offset? If I offset, it gives me a little bit more room on the side where we load on and off.

3. Can I add a weaver leaver or is there not enough space because of the stanchions?

4. Do I need more robust backing plate for the mounts or are the washers sufficient?

5. How far back from the edge of the platform should I mount the brackets?

5. Any other input before I get started would be great!

I'll probably have more questions, but this should get me going.

Thanks!
Bobby

 

[BB marine]

2. Should I center the davits on the swim platform or offset? If I offset, it gives me a little bit more room on the side where we load on and off

My opinion is center it the swim platform. The less over hang port/starboard the better. On the 8'6 wide boats there is over hang and the spray from the hull hits the rib. I did an offset on my installation only because I have a 8'10" inflatable mounted to a 8' swim platform.
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4. Do I need more robust backing plate for the mounts or are the washers sufficient?

I would make two stainless steel plates the foot print of the davit base or ‘Quick Kit’ Shoes . From what I have found the platform construction is a bit sketchy. The platform uses wood for a backing or filler. The deck of the platform is approximately 1/4 " thick fiber glass and mat, then wood and a thin layup of glass on the bottom side, painted with a rough layer of gelcoat. I would suspect that if just washers are used over a period of time it will crack the under side Gel/fiberglass and then there will be water intrusion. (As a side note to this inspect all hardware mounted to the underside of platform. On my C26 there are several places where NO SEALANT is present. When I mounted my weaver davits to the platform there was moisture in the platform all ready. I know of a C28 owner that just replaced his platform because it was water saturated and coming loose from the hull. His boat is a 2016 model. Cutwater forgot Sealant!) Ranger might have better quality control but I would still inspect.

5. How far back from the edge of the platform should I mount the brackets?

I mounted mine as close to the aft edge of the platform just enough room for the under side support plate to fit tight against the platform lip that the fenders are mounted. Look at the photos from my album. The location is as for aft as I could go and have a good mounting area underside for the support plate. I have towed the boat with the inflatable mounted 60 mph and cruised in different water conditions for three years with this installation without issue.

Note: closely measure the center point of the already mounted to rib "Davit grips" These need to be on center to the Davit mounts and will determine any slight offset side to side that you have to make. If the pads were factory installed for a Ranger Tug the factory should have exact mounting dimensions.

 

[Bobby P.]

Thanks Brian,

I mounted this up over the weekend and it worked out pretty good. It is a 9'6" rib. I should have mounted it even further from the port side, as I do catch a little spray when getting over 12 knots.

Thanks for your help.

Bobby

 

[Beautiful Grace]

Bobby P can you post some pictures. We have a Cutwater 28 and I just purchased the 4"up & 4" out Weaver Davits and I am having the same thoughts about offset of the dinghy. We also have a 9'6" dinghy and we are planning to install the Weaver Leaver system so we don't have to remove the outboard. Any advice on what you would do different, if anything would be greatly appreciated.

 

[Bobby P.]

I'll be getting back out on the boat next week. I'll take some pics and post.
Note, the original post is over a year old. In short, the mount job I did (following BB's advice, has held up nicely.
Bobby

 

[Kimberly Dawn]

I'm interested in this thread for not only installation of the davit, but also the selection of the davit system and the dinghy itself.

We have ordered a R29S due this next spring. My back says don't think about trying to transfer a motor onto/off of the dinghy. I had not considered the Weaver Leaver, but had considered the Olsson and Sea Wise davits where the motor transfer is unnecessary (Olsson) or mechanical (Sea Wise).

I'm also interested in a dinghy that incorporates a steering console with an aft bench seat for 2, yet fits behind a R29.

Does anyone have thoughts about these options?

Bob
The Doghouse 2

 

[bluestreak]

Our 2016 R-27 is equipped with the Olsson Davits.
The dinghy is a 7'10" Achilles rib with a 5 HP Honda OB.
It is slightly offset to port allowing a little more room near the transom door.
The davits are mounted close to the transom on the swim step.
Points to consider with the Olsson's.
It is a heavy duty system and does add some weight to the stern.
The side latches on the propane locker had to be moved to the front of the container to clear the davit arms.
With the davits lowered, one has to step over the tubes to access the dinghy.
I did add an elecrtric winch to hoist the boat and motor.
The boat is in charter and not knowing the physical abilities of the charterers, their safety was of concern.
Good point.
The OB stays on the dinghy since it always stays more or less horizontal.
Hope this helps.
Bill

 

[MV Toujours]

Bobby P can you post some pictures. We have a Cutwater 28 and I just purchased the 4"up & 4" out Weaver Davits and I am having the same thoughts about offset of the dinghy. We also have a 9'6" dinghy and we are planning to install the Weaver Leaver system so we don't have to remove the outboard. Any advice on what you would do different, if anything would be greatly appreciated.

I have considered the Weaver Leaver but came to the conclusion that I would have to remove the swim platform rails to make it work. I prefer to keep them.

I have a Yamaha 6HP that is easy to move by hand but I am going to install a Kato Outboard Lift as soon as they can make it so I can eventually upgrade to a 15HP, which is too heavy for me to move without a lift.

Patrick