Custom/Hybrid Rocker Square/Shortened Hull (PICS and process)

jeepmark4x4

Backflip, weeee
Joined
Jul 13, 2006
Likes
8
Location
Marietta, GA.
#1
The goal is to build a back-flip hull off small boat wakes with stock 701/b-pipe power.

Build talking points:

- Rocker nose
- 2" setback pump
- Shortened rear by 6"
- Cut hood down and take out liner
- Add cooling lines
- Defoam and custom widened tray (U.S. Composites 4 lb. foam)
- Fancy footholds (copying the Freak)
- Move exhaust lower
- Mount the X Metal pole bracket
- Paint & turf

 
Last edited:

jeepmark4x4

Backflip, weeee
Joined
Jul 13, 2006
Likes
8
Location
Marietta, GA.
#4
So the nose I cut from that divot in front of the gas cap to under the front rail lip. The ribs are cut at 1 1/2 inches apart and I did 11 cuts (the more the easier the curve up). I used a drimmel tool to start the cuts then I used a reciprocating saw with a straight wood blade. I shimmed the cuts up carefully as to not crack the glass as it is somewhat weak at this point. After I got the nose where I wanted I glassed between the shims to hold that position. I then took at each set of shims glassing one side at a time.

xh2o.1.1.jpg xh2o.3.jpg xh2o.5.jpg xh2o.6.jpg xh2o.4.jpg xh2o.12.jpg xh2o.11.jpg xh2o.13.jpg xh2o.14.jpg xh2o.15.jpg
 
Last edited:

jeepmark4x4

Backflip, weeee
Joined
Jul 13, 2006
Likes
8
Location
Marietta, GA.
#5
IMPORTANT: After glassing the inside of the nose. I used West Systems Six10 Epoxy filler to fill the gaps in the ribs of the nose. This stuff is AWESOME. Not very expensive and just makes life so much easier. Doesn't run and is incredibly strong.

xh2o.19.jpg xh2o.20.jpg xh2o.31.jpg

Some leftover pictures from the previous post. I hit the 10 file upload limit. WHATEVER YOU DO, DO NOT CUT THE LINE DOWN THE BONDLINE LIKE I DID. DO NOT DO IT. There is a better way to do it. Cut off the lip of the bond line, the overhang needs to be cut. It will be WAY easier to curve the nose up. The fiberglass is not strong enough to curve where I cut it.

xh2o.32.jpg xh2o.33.jpg xh2o.34.jpg xh2o.35.jpg
 
Last edited:

jeepmark4x4

Backflip, weeee
Joined
Jul 13, 2006
Likes
8
Location
Marietta, GA.
#6
To close that hole in the nose I used that pink foam you can get from Home Depot and that 'foam in a can'. I used the pink foam as the platform to hold the spray foam and just shaped it to what I had imaged in my head. Honest, I had no idea what I was trying to do, just kept sanding and hoped for the best.

I used a buffer/sander I got from Harbor Freight for majority of my sanding. The reset is done by hand with a sanding block.

After the sanding, just glass 'er up! I had the ski on her tail end for this part of the process.

xh2o.18.jpg xh2o.21.jpg xh2o.22.jpg xh2o.23.jpg xh2o.24.jpg xh2o.25.jpg
 

jeepmark4x4

Backflip, weeee
Joined
Jul 13, 2006
Likes
8
Location
Marietta, GA.
#7
I cut the back end of the ski down about 6 inches I think, can't really remember. This part was relatively easy compared to the nose.

xh2o.2.jpg xh2o.1.jpg xh2o.27.jpg xh2o.28.jpg xh2o.37.jpg xh2o.38.jpg xh2o.39.jpg xh2o.40.jpg xh2o.29.jpg

I also moved the pump back 2 inches which I will get pictures of that tomorrow. I hope I can find them!
 

jeepmark4x4

Backflip, weeee
Joined
Jul 13, 2006
Likes
8
Location
Marietta, GA.
#8
I added a few cooling lines in the process.......I forget to take pictures of the progress. But I have foamed the tray and used the "cutout" of the old tray as the foam template. I got the 4 lb. foam for strength and ease of carving. My footholds will probably mimic the superfreak as I really like how those look and it will be somewhat easy to cut. I should be finished forming the tray/footholds tomorrow and glassing should commence soon.

xh2o.44.jpg xh2o.46.jpg xh2o.45.jpg xh2o.43.jpg xh2o.41.jpg xh2o.42.jpg
 
Last edited:

jeepmark4x4

Backflip, weeee
Joined
Jul 13, 2006
Likes
8
Location
Marietta, GA.
#10
Starting in on the footholds. I am going to form an extended lip to cover the foot better.

What is everybody's opinion on having the foot lower then the top of the pump housing?


foothold1.jpg foothold2.jpg
 

BruceSki

Formerly Motoman25
Joined
Nov 6, 2007
Likes
2,588
Location
Long Island
#13
Those footholds are wicked! Look like xft

You're making me want to build another one. Kinda fun taking a stock square and turning it into something more fun.
 
Last edited:
Joined
Oct 7, 2012
Likes
0
Location
south africa
#14
mate that issssss sickkkkkk I'm about to get started with a project like this but was just going to buy a rocker nose kit but i will cut the tray, seriously mate yours looks sickkkk
 

jeepmark4x4

Backflip, weeee
Joined
Jul 13, 2006
Likes
8
Location
Marietta, GA.
#15
Thanks a bunch. The entire conversion I have about $350 in resin and cloth. It has been a HUGE project so far only because I am a bit anal about cutting corners. I would have shortened up the tail but I set back the pump 2 inches and needed all the tray I could get.

The footholds were done in 2 stages.

The first stage was using the old tray as the mold for the foam, so I basically took it back to stock form. I formed the general shape I wanted as you can see in the previous pictures.

The second stage was making a cardboard mold of the fin looking parts. I will take pictures of my molds, they looked like crap, they were bulky and square.
 
Last edited:
Joined
Jun 7, 2016
Likes
3
Location
Huntsville, AL
#20
I believe I just received this Hull. Going to be my first major ski project and first freestyle ski with the goal of back flipping. Ive previously had an '88 JS550 and 2014 SJ.

Ski came with a 61x motor with Protec milled head and a 44 carb. 144 pump with driveshaft, RIVA Groovy Rideplate, Steering Cable, and 2" setback pump.

Going to begin preparing my build list, so if anyone has any ideas I would love some suggestions!
 

Attachments

Top Bottom