FC Cheetah Twin

[bill34207]

Before totally comitting to that location and doing aluminum you may want to make it from 1/8" lite ply and try the motor fit. Even with the short 4068 sized motors in mine it's a pretty tight aqueeze. The bottom of the cooling jacket is about 1/16" from the bottom of the sponson and the top side is pretty close to the top of the hull. If you were doing shorter can motors and moving the mounts forward a little, Dave already has the cnc program done for cutting them.

[RCKong]

Thanks Bill. I knew Dave was making those mounts, but with my motor location farther a stern I knew the mounts would not fit because of the shape of the hull. I actually fit the motor to the cardboard mount to check for clearance and it seems ok, just gonna be a PITA getting motor bolts in and out. The tear drop motor bolt holes Dave has in those mounts will be next to impossible to duplicate by hand. I might get a set from him and grind them down to fit closer to the transom.

[bill34207]

You got that right about being a PITA for the engine mounting bolts, even with the motors as far forward as mine are. Mine is actually a bit tail heavy with them where they are, too. (You didn't see it but there's a 6 oz packet of lead at the front of the tunnel to get a 32% CG on it) I wish there was a little more room between the tunnel floor and the top and I would have mounted the motors on the tunnel floor and run struts instead of stingers. A single fits nice under the hatch but the canopy isn't quite wide enough to accomodate 2 motors side by side. That would have solved a lot of issues like the cramped quarters for the motor mounting bolts, the ability to slip in a pair of 5000ma 6s packs, finding a stinger that works without some kind of mods, etc.
Speemaster stingers will fit the sponsons too, but you can't get to the adjustment screw for changing the angle without taking them off the boat or drilling an access hole to get to it. I think that's what Scott is going to do to his when he finally gets around to building it. That and add a tube around the hole the comes out the top of the hull to keep water out of the boat.

[LOVE6S]

Question about mounting the motors on the floor. I want to do one of these in the future, I was thinking about all the stuff you where talking about, and would rather use struts, what if you mounted the motors on the outside part of the floor and angled the front part of the motor, the part towards the bow in towards one and other, and had a little bend in the stuffing tube. The high part of the motors the front of it would be in the middle of the hatch, what do you think, Shawn?

[bill34207]

Not wanting to get Brian's thread too far off the build he's doing Shawn. (my aplogies in advance Kong). You might get a pair of 36 mm motors on top of the tunnel but with the added diameter of the cooling jackets on a 40 mm can there is no way. At least not that I could come up with. About the only thng I didn't try was staggering the motors (one ahead of the other).

[RCKong]

Bill if you have Daves ph # send me a PM. It's not listed on the club list I have.

[LOVE6S]

Thanks, sorry to distract the thread, just been thinking of the whole stinger vs struts thing.

[bill34207]

Bill if you have Daves ph # send me a PM. It's not listed on the club list I have.

You should have it now.

[RCKong]

thx

[RCKong]

I made some progress with the mounts for this. It was a bit of work but it was worth it. They turned out nice.
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[srislash]

Nice Brian,very nice.How are you going to make sure of a good bond?

[bill34207]

Maybe it's just the camera angle but it looks like you have the mount only about 2" from the transom in the photo. Are you planning to add some ply doublers to the sponsons for stinger support?

[RCKong]

Nice Brian,very nice.How are you going to make sure of a good bond?

I might drill a few holes around the mount for epoxy to run thru.

Bill it is the camera angle 4 sure - nearly 4". should be enough we'll see.

[srislash]

I might drill a few holes around the mount for epoxy to run thru.

That is what I do with my CF stuff and nothing has let go yet.And I have had a few 70+ blowovers.

[RCKong]

I managed to spend some time on this today, trying to get the drives sorted out. It was going ok until the drill broke a nice size chunk of gel coat out of the port transom. nothing a little glass won't fix.
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I sand then tack things in place with CA. I think I will build up the transoms, its a lot thinner than I thought.