General discussions - FAST RC boat

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Who is the guy that went out of radio range :LOL:

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Oh man that stinks!

I love this one:

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No idea what this truly was, but it was either a Gator or a turtle.
1st pack and initial warning, rudder was bent up, and I headed straight into the embankment, luckily very soft, but it was buried ~ 1 ft.
No damage except the plastic screw. Temp fix with a zip tie as I had no replacement.
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3rd pack of batteries, now this happened going ~ 50mph, a bump, a loud noise and utter carnage.
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and upon further inspection, the transom is split as well.
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The strut is toast as well. Now I know what to work on in the next couple of days...
 
Ugh.. that is awful..☹️.. can't believe it bent the stub like that.. was a hell of a hit.. what do you suppose ripped into the hull like that?.. by the looks of the prop on the stub it doesn't seem like it could reach the hull..🤔..

Think a gator took a chomp onto it?. Seems highly unlikely at that speed though..🤔🤔.. crappy regardless.. time to work some fiberglass..👍
 
Yes, it was the prop that chipped the gel coat. The entire strut was ripped out and with the unbalanced prop there was enough reach.

It probably skated across the ridgy back of the gator. That massive of an impact on the prop must have hit something hard.
That is 3/16 solid steel, and it's roughly a 45-degree angle. I couldn't do that with a hammer on 1 hit.



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Sorry it was late.. lol.. I wasn't paying attention to well..🤦.. I now see the strut was mated to the large opening in the hull.. I was to focused on the stub shaft being smoked.. what ever it was was solid for sure.. not an easy task to bend a 3/16" stub.. do you silver solder your own flex shafts to the stubs? Or buy them made.? I may have some stubs left over from the days of making flex shafts if you indeed solder them yourself..👍
 
Much appreciated, I do buy mine either from Offshore or AliExpress but shipping is a nightmare. I have plenty of spares though.
Speedmaster is currently the cheapest all said and done and he cuts to length as well.
Looking into the wires drives, most likely my next update. I was trying to go for +100 next week, this was a trial run with new batteries but this little 'ouch' put a damper on that attempt.
I'm sure it can be fixed, never done this type of repair, but there is always a first!.
 
How about a tugboat with an arm to corral any floating issues?
I had a tugboat set up the same exact way. But during my 'Tunnel-Hull' era, I was forced to use a raft since trim tabs (and gyros) were not around. I also ran submarines with my ex-Navy brother who set up a sub reggata in Groton Connecticut, right there at the sub base he trained on. Submarines are the elite both in the military and the R/C world. My and my brother knew of gyros made for helicopters, which were the only units available. We both designed a sub gyro using a heli gyro by flipping it on its end. It worked great and was the defacto setup until sub gyros were invented..

And I wish I had a picture of my Aeromarine catamaran, powered by am OPS .90 (that's 15cc).. Much easier to trim and although Brushless motors finally ruled there is nothing that looks like a trimmed-out Cat doing turns at unheard-of speeds while the Italian motor screams in the distance.

I am into drag racing my cars but if I do baots again, it's OPS all the way.
 
Yes, it was the prop that chipped the gel coat. The entire strut was ripped out and with the unbalanced prop there was enough reach.

It probably skated across the ridgy back of the gator. That massive of an impact on the prop must have hit something hard.
That is 3/16 solid steel, and it's roughly a 45-degree angle. I couldn't do that with a hammer on 1 hit.

Yeesh! Bad lucky lately. That was one heck of a hit!

Maybe you should throw some dynamite into the pond before you start...
 
Going to resurrect this thread with a new topic to dive into for FE boats ~ Tunnel Dams on Cats.
Knowing a high level approach about much of the science behind it, and lift, it seems like most of the tribal knowledge out there is just accepted misinformation.

Airfoils create lift by splitting the air current, routing it along a farther route above the airfoil, and creating a low-pressure area. It seems like these catamarans do the same thing, and that using a tunnel dam reverses the effect.

It is well known that a tailgate on a pickup truck keeps a relatively stagnant vortex in the bed, and the majority of airflow rides over the top of it. Tunnel dams likely do the same thing, routing the airflow under the hull along a longer path, over a (relatively) stagnant pocket behind the dam and forcing the air below the hull along a longer path, likely not to the degree of creating negative lift (downward lift) but at the very least greatly reducing the airfoil effect of the hull.

At least, that is my $0.02 about it.

Ground effect, boundary layer, etc. could throw a huge wrench into my theory, but it seem much more reasonable than "It makes turbulent (slower) air under the hull and keeps the boat from getting pushed up like a sail."
 
Going to resurrect this thread with a new topic to dive into for FE boats ~ Tunnel Dams on Cats.
Knowing a high level approach about much of the science behind it, and lift, it seems like most of the tribal knowledge out there is just accepted misinformation.

Airfoils create lift by splitting the air current, routing it along a farther route above the airfoil, and creating a low-pressure area. It seems like these catamarans do the same thing, and that using a tunnel dam reverses the effect.

It is well known that a tailgate on a pickup truck keeps a relatively stagnant vortex in the bed, and the majority of airflow rides over the top of it. Tunnel dams likely do the same thing, routing the airflow under the hull along a longer path, over a (relatively) stagnant pocket behind the dam and forcing the air below the hull along a longer path, likely not to the degree of creating negative lift (downward lift) but at the very least greatly reducing the airfoil effect of the hull.

At least, that is my $0.02 about it.

Ground effect, boundary layer, etc. could throw a huge wrench into my theory, but it seem much more reasonable than "It makes turbulent (slower) air under the hull and keeps the boat from getting pushed up like a sail."

Yep if you look closely you will see some high-speed guys do this.
I wish I had saved the picture. I know one of them was using adjustable trim tabs from a mono so he could fine-tune it.

A really interesting thing also is that guys take large extended struts and bore the holes larger to accept ball bearings. This particular cat is a world record holder at 153 mph. Notice it is a single prop?!!!

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Maybe it is the warm weather, but feeling the pull back to the water.
Planning on picking up a nicely built JAE 33 FE rigger this weekend and start going really fast.
Comes with a neu 1515 motor and several nice props. It has a flycolor 150a esc but I'll likely swap in an XLX2 :cool:
 
Maybe it is the warm weather, but feeling the pull back to the water.
Planning on picking up a nicely built JAE 33 FE rigger this weekend and start going really fast.
Comes with a neu 1515 motor and several nice props. It has a flycolor 150a esc but I'll likely swap in an XLX2 :cool:
I feeling it. I work at a marina in the summer. This is tough. I want rc boats here
 
Build one myself and yes, back to water during summer. The only issue is very low water levels in the lakes right now, but that will change soon. First tropical depression already bringing rain.

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Was checking one of these out on YT. Looks like they need a very smooth surface to run on eh? I'm definitely interested in a boat, have a lake thats 150 yards off my property. Afraid I'll bore of it quickly though..
 
Riggers are probably the best for rougher water as well.
Don't know on it getting boring, it will show you that all your lipos suck and you melt connectors a lot .:ROFLMAO:

It will be short runs, fast and furious type and you will need a retrieval method i.e. minimum is 2 boats.

Learned a lot and still enjoying it, I have 1 of each type. V-hull (actually 2), Cat (single), CAT (dual motor), Hydro and rigger plus a retriver.
 
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