Stingers for 41" Sprint Cat, Buy or fabricate?

[78MaicoRider]

I plan on opening a build thread when I can get rolling on this boat build. But for now my question is on stinger adjustment. I have machine tools (lathe and mill) to fabricate my own stingers. It would greatly simplify fabrication if they were non adjustable and perpendicular to the transom. I can offset the prop shaft bore to be low as possible. Right now I was thinking of going with 3/16 prop shafts with cross drilled oil impregnated brass bushings,(but looking at "plastic" bearing material too) and using .074 wire drives which I would also fabricate. This is for twin fightercat 3730s 1600kv 2700W on 6s in a 41" sprint cat. Not sure if the 3730s are going to be enough grunt for this hull. Anyone have input on any of this? Is angle adjustment away from parallel with the bottom required? Since there is no transom overhang, how long should stingers be on this hull? Bearings vs bushings, bearings move the prop shaft higher on the transom. I welcome any input you might have.

Thank You!

[78MaicoRider]

Been a couple days and no one has looked at my post. I welcome all ideas and insight! Really could use some help with this.

[Fluid]

You will want the stingers to have some kind of adjustment for vertical angle. Without that all you can do is shift the CG to control ride attitude.
With today's power the 0.074" wire is pretty small. I'd opt for 3/16" cable or 0.098" wire.
Bushings will be just fine.
Stinger length? 3"-4"
I'm not familiar with those motors. What are your speed goals? Run time goals? Handling goals? Twin 4082/4092 inrunners are plenty.



.

[grsboats]

I have a Sprint cat 41 used to make molds for a Fe cat and what I can say is that those motors aren't enough for this size cat.You better of think of being using bigger motors like a pair of 5682 with low kv(1390) and adjustable stingers with 4"lenght or more keeping the Cg around 30-32%.4092 are a good option but from my experience I had better performance with 56"motors.teflon bushing work good with 3/16 flexcables and would be my personal preference.Gill

[iridebikes247]

http://www.tppowerusa.com/motors/inrunners

Found that link last night. I would use the 3/16" flex cables as grs boats said. The fightercat t600 style motors will be more than enough if they're just like the t600 turnigy motors. They have a lot of torque but the only thing is you need to get a motor mount to properly cool them. Williams racing aka southriver rc boats makes water cooled mounts, fightercat does too.

[78MaicoRider]

These outrunner motors are 2700 watts 4-6s. Thats in the same range as a 4074 inrunner. I was planning to fab motor mounts. All 3 designs are high water flow. Even worked out a design that would be direct fed through hull water cooled. When I was acquiring this hull, I thought it was a 36" not 41" Sprint Cat. Changing hulls is less $$$ than bigger motors. I am considering a Fighter Cat Cheetah hull. I think a Mean Machine hull is too small for the two 6s 5000mah 50c packs I have. Running a single pack, run time would be too short. I am looking for 50+ MPH and turn WOT. Fabricating parts to not go further over budget. Besides the lathe and especially the mill takes up alot of space in the garage and needs to pay their way.

[iridebikes247]

I ran t600 motors 1400kv on 6s in a 41 cat it went 65 mph and turned wot.

[78MaicoRider]

That makes me feel better about this. These motors are 1560kv actual. What 41" hull was it and what props did you run?

[twissted]

Nice find! I'm saving it in my favorites. Thanks! So what happened to your Super Daytona?

[twissted]

I have the the Hor Racing Zonda. If you look at these boats they are fast out of the box. But have some short comings that you will need to address. The stingers that come with the boat can also be found on ebay and other wed sites. I like them and they work great and at a great price.
You may want to try one and see if it is something that you could make better such as bearings instead of bushings.

[iridebikes247]

I ran them in an mhz nomad xl

http://www.youtube.com/watch?v=gAe5p-DtJvw

Thats with leopard 4082 1600kv I put the outrunners in a mono. I was running x447 prop on 6s with seaking 180. On 5s I ran the seaking 120 and had no issues. Those outrunners have some power I ran an x447 on 4s 10,000 mah t600 1400kv motor in a 41" mono. It was 100 degrees out and I didn't have water cooled mounts either lol motor came back at 135 degrees not bad at all.

They will do well in that boat and sound really cool. Below is the same boat but previous owner with t600 motors.

http://www.youtube.com/watch?v=s1xLP-B27B0

@Twisted the super daytona was sold to a member on here, in its place is now a mystic 138

[twissted]

They sell for the pair, under 100.00 and are strong. I have since painted the boat green so they even look better lol!

[twissted]

So how do you like the Mystic 138? is it as nice as they say? is it faster? is the quality as good as the central marine mystic? I want to do anther boat build and was looking at the mystic from central with the added carbon to boat the pan and the hatch.

[Eodman]

Jim from South River does exceptional work. Easy to work with and quick!

[Cooper]

I have the the Hor Racing Zonda. If you look at these boats they are fast out of the box. But have some short comings that you will need to address. The stingers that come with the boat can also be found on ebay and other wed sites. I like them and they work great and at a great price.
You may want to try one and see if it is something that you could make better such as bearings instead of bushings.

Not that strong. I wish I would have went with the click drives. But depends how much you are stressing them, fine for sporting but for punishment they are weak.