10' 11" RIB Tiller to center console conversion. For a Yacht tender.

[Sieben]

Hi there. My 2nd post. I have a West Marine RIB 10' 11" Hypalon aluminum boat, which is the dinghy to our Tollycraft 44 CPMY. I need for my wife and 2 labrador dogs to be able to get in and out easily. I would like a nice center console RIB but they cost $8-30K. Hence this project. A plastic mini console costs about $500 plus shipping. So, I decided to make one. I traded my 2 stroke Mercury 15HP for a 4 stroke long shaft Mercury 20 HP set up for wheel steering. Bought an Ice Chest seat. The back folds forward or backwards for seating in either direction.

Then I need: Throttle cables, Shift cables, a console, wheel, running lights, battery etc. With a 15hp this boat would plane with 2 people and a 75lb dog. 4 people it would not. This dinghy will be on davits behind our Cockpit Motor Yacht. I have found lots of useful build data and information on this site. It is quite helpful and much appreciated. I'm hoping to contribute to the build section.

The build briefly:

1. I mocked up a center console out of cardboard. I cut out the console with 2 tube curved circles to be able to slide the console further to the starboard side. This gained me 3-4" in the center of the boat. Every inch gained is important in such a small boat.
2. I did a 4" cut out at the bottom for feet to be able to slide under the center console providing more feet room.
3. Used 1/2" plywood and solid oak for the framing. Sealed the wood all around with West System epoxy. All of the support "Cleats" are glued together with Epoxy and 406 thickened microballs.
4. Offset the console to the starboard side for more room for our dogs moving around.
5. I have a fixed 4" offset jack plate to mount the motor.
6. The fuel tank I found a rectangular smallest shape which will fit in the bow. 6 gallons. I need to keep the weight in the bow.
7. Next I need a bow platform for the dogs to get in and out. Likely this will be 1/2" plywood. This will go over the fuel tank. I'm open for suggestions of a different material. The support has to support 65-100lb dogs plus people to walk on it. It can be tied into the 2 aluminum lifting supports to keep it in place. It will be vented at the aft end of the supports.
8. The top of the console is about 6" wide. This will house 2 ss cup holders and a SS hand rail.
9. The 30 degree angled area is for the Steering wheel, shift lever, and a 6 panel switch set. Bilge pump, nav lights, etc.
10. The entire console will be rounded with a 1" half round on all edges. Sealed with 2 coats of epoxy. Then primed and painted with marine polyurethane.
11. The AGM battery will be housed inside of the console as well as wiring, on off master switch and circuit breakers etc.
12. The console will be thru bolted and glued with 4200 to the double floor of the dinghy.

Questions you might be able to help me with are below.

1. What is a good durable material for the top and the control wheel area. I'm considering G10, star board, or something which is not wood but would hold up well.
2. What is a good material for the bow platform for the dogs? VS wood epoxy coated and covered in indoor outdoor carpet. The labs need something to hang onto with their feet. As well we harness our dogs with lifejackets. The plan is to have 2 pad eyes on the front section of the console to attach the dog harnesses to.

Let me know if anyone is interested in watching along. Some pictures have been attached.

John

 

[thill]

You could make the front platform out of PVC board available at Home Depot or Lowes type stores, with aluminum angle as support. Woud be nice and light, and will never rot.

They make an excellent clear self-adhesive grip tape that goes well on boats. Would be perfect for dogs and people, and you can put it in various locations, as needed.

I hope it goes well! It looks good so far.

 

[flatheadsteve]

Starboard would last forever and makes for a nice surface to mount gauges or rocker switches to. I'd put down the cheap Amazon Eva foam flooring for the dogs. It's padded but won't show any claw marks unless they really dig into it.

 

[thill]

King Starboard is very dense and heavy and somewhat brittle. Not a great flooring material, IMHO.

PVC board is pretty light, but requires good support.

 

[Sieben]

Hi there. My 2nd post. I have a West Marine RIB 10' 11" Hypalon aluminum boat, which is the dinghy to our Tollycraft 44 CPMY. I need for my wife and 2 labrador dogs to be able to get in and out easily. I would like a nice center console RIB but they cost $8-30K. Hence this project. A plastic mini console costs about $500 plus shipping. So, I decided to make one. I traded my 2 stroke Mercury 15HP for a 4 stroke long shaft Mercury 20 HP set up for wheel steering. Bought an Ice Chest seat. The back folds forward or backwards for seating in either direction.

Then I need: Throttle cables, Shift cables, a console, wheel, running lights, battery etc. With a 15hp this boat would plane with 2 people and a 75lb dog. 4 people it would not. This dinghy will be on davits behind our Cockpit Motor Yacht. I have found lots of useful build data and information on this site. It is quite helpful and much appreciated. I'm hoping to contribute to the build section.

The build briefly:

1. I mocked up a center console out of cardboard. I cut out the console with 2 tube curved circles to be able to slide the console further to the starboard side. This gained me 3-4" in the center of the boat. Every inch gained is important in such a small boat.
2. I did a 4" cut out at the bottom for feet to be able to slide under the center console providing more feet room.
3. Used 1/2" plywood and solid oak for the framing. Sealed the wood all around with West System epoxy. All of the support "Cleats" are glued together with Epoxy and 406 thickened microballs.
4. Offset the console to the starboard side for more room for our dogs moving around.
5. I have a fixed 4" offset jack plate to mount the motor.
6. The fuel tank I found a rectangular smallest shape which will fit in the bow. 6 gallons. I need to keep the weight in the bow.
7. Next I need a bow platform for the dogs to get in and out. Likely this will be 1/2" plywood. This will go over the fuel tank. I'm open for suggestions of a different material. The support has to support 65-100lb dogs plus people to walk on it. It can be tied into the 2 aluminum lifting supports to keep it in place. It will be vented at the aft end of the supports.
8. The top of the console is about 6" wide. This will house 2 ss cup holders and a SS hand rail.
9. The 30 degree angled area is for the Steering wheel, shift lever, and a 6 panel switch set. Bilge pump, nav lights, etc.
10. The entire console will be rounded with a 1" half round on all edges. Sealed with 2 coats of epoxy. Then primed and painted with marine polyurethane.
11. The AGM battery will be housed inside of the console as well as wiring, on off master switch and circuit breakers etc.
12. The console will be thru bolted and glued with 4200 to the double floor of the dinghy.

Questions you might be able to help me with are below.

1. What is a good durable material for the top and the control wheel area. I'm considering G10, star board, or something which is not wood but would hold up well.
2. What is a good material for the bow platform for the dogs? VS wood epoxy coated and covered in indoor outdoor carpet. The labs need something to hang onto with their feet. As well we harness our dogs with lifejackets. The plan is to have 2 pad eyes on the front section of the console to attach the dog harnesses to.

Let me know if anyone is interested in watching along. Some pictures have been attached.

John

Update
Console progress and fwd fuel tank cover mock-up. This area one will be able to sit or stand on. There will be a hinged vented door to access the fuel tank. Purchased a Suzuki 20 hp with trim and tilt. Some progress.

 

[Sieben]

Hi there. My 2nd post. I have a West Marine RIB 10' 11" Hypalon aluminum boat, which is the dinghy to our Tollycraft 44 CPMY. I need for my wife and 2 labrador dogs to be able to get in and out easily. I would like a nice center console RIB but they cost $8-30K. Hence this project. A plastic mini console costs about $500 plus shipping. So, I decided to make one. I traded my 2 stroke Mercury 15HP for a 4 stroke long shaft Mercury 20 HP set up for wheel steering. Bought an Ice Chest seat. The back folds forward or backwards for seating in either direction.

Then I need: Throttle cables, Shift cables, a console, wheel, running lights, battery etc. With a 15hp this boat would plane with 2 people and a 75lb dog. 4 people it would not. This dinghy will be on davits behind our Cockpit Motor Yacht. I have found lots of useful build data and information on this site. It is quite helpful and much appreciated. I'm hoping to contribute to the build section.

Update: fuel tank dog platform.

 

[Sieben]

Update: Pre-fitting the console and seat placement while aligning with the 4" 1/4" thick aluminum davits. Davits to be painted. Hoping to get the steering, lights and electrical installed this weekend. More painting to go on the console before final assembly. I'll use SS rivet nuts to thru bolt and glue it with 4200 to the floor.

 

[Sieben]

More progress.

 

[Sieben]

More progress.

Just about complete. Took her out for a test spin. I’m getting a bit too much now rise on takeoff with just myself in it. About 3 of 6 gallons of gas in the bow. Powered by a 4 stroke Suzuki. Battery is behind the seat on the port side offsetting most of the console weight.

I’ve been told by friends with a commercial built tender such as mind to add a whale tail to the cavitation plate. Anyone who HAS done so and what was your experience? Not too keen on drilling 4-6 holes in my brand new motor.

John

 

[Sieben]

More progress.

 

[flatheadsteve]

The whale tale may or may not help I have limited experience with them. In my case on a 10ft tin and 9.9hp it did not help. Are you applying the throttle slowly? If so instead try a quick hit say 50% throttle seems counter productive but the extra power will help lift the stern. Adding ballast as far forward as possible can help too. 20hp on boat that size seems like a lot but I'm not very familiar with ribs.

 

[Crazyboat]

You went from a short shaft to a long shaft, did you raise the transom at all? If not you'll find handling poor at speed and maybe even dangerous.

 

[Sieben]

More progress. I went with marine grade carpet glued to the fuel tank dog platform. Hinges up to remove the tank.

You went from a short shaft to a long shaft, did you raise the transom at all? If not you'll find handling poor at speed and maybe even dangerous.

I had a long shaft Mercury shown in an early photo. It mounted up way too high. So, bought a short shaft Suzuki 20hp with a mini Transom Jack. Raising the Short shaft about 2 1/2" from the original transom height.

 

[Sieben]

The whale tale may or may not help I have limited experience with them. In my case on a 10ft tin and 9.9hp it did not help. Are you applying the throttle slowly? If so instead try a quick hit say 50% throttle seems counter productive but the extra power will help lift the stern. Adding ballast as far forward as possible can help too. 20hp on boat that size seems like a lot but I'm not very familiar with ribs.

It performed better with a slow roll on the throttle. Hammering the throttle sent the nose up. My two buddies with the same configuration and size. One has a 11" with a 25 4 stroke with 25 lb of sand in the bow locker 6 gallon fuel tank up forward and a whale tail. It is like an instant rocket to planing. My second buddy has an 11' with a 25 hp 4 stroke 3 gallon fuel tank up front with a whale tail and his goes like a rocket also. No sand on his.

First I'll fill the fuel tank to 6.5 gallons. It had 3 in it. The seat can go forward 2" which will also move the battery 2" forward which is in the port stern corner. The battery is strapped to the fiberglass seat currently. I have a bit more testing to do before I add the whale tail. I could also add the 20 lbs of sand up in the bow locker. The 4 stroke is much heavier than my old 15 hp 15 hp 2 stroke by 65 lbs. About 125 lbs just the motor, battery 45, console 40, seat 30, boat 120, fuel 20. So, about 380 lbs total. The 20 hp should be plenty.

Thank you for replying. John

 

[Sieben]

I had a long shaft Mercury shown in an early photo. It mounted up way too high. So, bought a short shaft Suzuki 20hp with a mini Transom Jack. Raising the Short shaft about 2 1/2" from the original transom height.

The Finished Davits and the Dinghy. Yet to add the seat back. Goes up and down in 10 seconds with the electric winch.

 

[Sieben]

Hello there. So the test run revealed that the 3/16” aluminum floor is not rigid enough. The console flexes the aluminum floor left to right. Or up and down. Especially towards the middle. The floor does not have bracing under it. I was going to unbolt the console from the floor. Cut a 2” w x 4” l slot across the bottom of the console.

Then bolt the console back down over the top of the aluminum tubing on top of a 2” x 4” x 36” long, the width of the floor aluminum 1/4” wall beam or tubing. This would stop just 2” inside the port and stb rigid flooring close to where the tube is. This will form a triangle with the rigid v- hull. The aluminum beam and the console will be bolted down to the floor with SS riv nuts with 1/4” bolts.

The outer edges of the 2” x4” x 1/4 wall tube will have the top ends cut back about a 30 degree angle such that the tubes don’t chafe. Ground and polished smooth.

If it tests ok, then I would likely glue the brace also with 4200 to the floor as well as the bolts. This would ensure strength and rigidity.

Any other suggestions you all might have? I have a lot into this but did not account for the floor to flex up or down which it does.


Thanks in advance. John

 

[LDUBS]

You did a nice job putting this together. Did you accomplish your original objective to make it easier for the wife and 2 labs to get in and out of the tender?

 

[Sieben]

Yes. Certainly easier. Lots of handles. And one does not have to get on your knees getting in and out from a dinghy dock.

You did a nice job putting this together. Did you accomplish your original objective to make it easier for the wife and 2 labs to get in and out of the tender?

 

[LDUBS]

Something to grab onto makes a world of difference. The frame for the canvass convertible top on my boat has to be up whether I use the canvass or not. Having that frame to grab onto getting in and out of the boat makes life a lot easier. Not much use for the pup though! Haha.

 

[waterant]

I was following your build, and it looks great. good job!
if someone is considering a similar conversion, I found this DIY central console, which seems like an easy and light build.