Sling Shot

[adam larvenz]

Thank's Blazer Marine I Ordered a Sling Shot kit and every thing has been Awesome . hope to have a new gas rigger on the water next yr . Adam larvenz

 

[Rich Jones]

Thank's Blazer Marine I Ordered a Sling Shot kit and every thing has been Awesome . hope to have a new gas rigger on the water next yr . Adam larvenz

Good luck on the kit. Just got mine on the water in late July. Below is a pic. If you go to the Cincinnati Model Boat Club Facebook Page, you’ll find a couple videos of it running during the last couple months.

 

[Roxyflash]

Rich I will be building it for Adam going to have a Cmb27 so probably made a custom tub and a regular tub for a zenoah.Have a gallon of west system so we have plenty of epoxy.When I get the kit will order some extra wood for the custom tub.

 

[Rich Jones]

I’m sure it will be a great boat. I’m enjoying mine. Drives really nice. I use the Gizmo 29.5 and 30 plus in it both with billet cases and noticed it was dimpling the bottom of the tub and starting to crack. I just cut a 2x3 area out and added a 1/8” deep mini belly pan and that took care of it. Weight added was practically nothing. Speeds are in the upper 70s to low 80s depending on prop and chop on the water. She loves running in choppy water.

 

[Roxyflash]

Would you mind posting a picture of the reinforcement I have a idea what your talking about the warlock I put together had a horse style reinforcement in the engine bay

 

[Rich Jones]

Sure attached are some pics. It’s just more of a relief than a reinforcement. The overall size is approx 2 1/4” wide by 4” long and you can see how I angled toward the front. It’s just 1/8” square spruce and 1/16” ply. Cut your hole in the bottom then glue the spruce sticks around it to create a frame. Glue on the ply and then I put 1 spruce crossmember in the angle seam inside the well for strength. Then just coat with epoxy in and out and you’re done. Took maybe 1/2 hour. This just created about an 1/8” more room for the lowest part of the motor case, which I felt was preferable over grinding down the case. The engine well itself is just reinforced with triangle stock in the corners.

You’ll notice those screws going through the bottom. Instead of threading the aluminum bushings for the booms, I just drilled them out for 8/32” oval head screws and used the special washers you can see. These go through the booms and have a nut and washer on the inside. This way the bushings won’t break through the epoxy with the twisting required to tighten into a threaded bushing. This is something Mario recommended from his build last year. I think it works great.

 

[Roxyflash]

On my scratch built rigger I did last year I did the screws with cupped washers the cmb is so big I may do a like you did to lower the motor in the tub

 

[Rich Jones]

On my scratch built rigger I did last year I did the screws with cupped washers the cmb is so big I may do a like you did to lower the motor in the tub

Now that I think about it, I did use a little fiberglass cloth on the outside for strength. So it wasn’t just epoxy, I used cloth too. Just on the outside of the belly pan, not in the engine well.

 

[Roxyflash]

I used two oz fiberglass on the inside of fuel tank and engine bay on my builds there’s a lot of stress in that area I have on my whip builds grind the bottom of case but then when to the 1/2 inch isolators there’s not much movement plus when there’s the 1/4 inch wood backer you can epoxy the engine side rails then use spacers to gap the bottom slide the engine in and let dry