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        Discussion Weed Eater Boat Build, Need Suggestions

#1 stompjrkz400 Jul 17, 2011 02:27 PM

Weed Eater Boat Build, Need Suggestions
Hey everyone, im working on a weed eater boat project, the motor is a clutched craftsman weed eater, it runs awesome, i took it off my weed eater rc car,

i have a few questions, since i still don't know much about drive setups on boat,

the boat is a fiberglass 46 inch hull, x 14 wide. i don't know what kit it was made from, got it used with no motor, i also got a 7.5cc outrigger, that i didn't want so i scraped it and i'm using all the hardware from it, the prop is 2 1/2 inch diameter.

i'm not looking to make a speed boat, i don't expect it from a weed eater that wont be tuned with a good pipe.

what have others used for there drive setup. i don't have a flex shaft setup, its solid, with very nice bearings. where i have the prop now just does not look right. i want a sub surface drive of some sort. right now the prop sits about 1.5 inches under the water static. the shaft come out a very good distant, and aims downward 8 degrees.

i would love to use the shaft already in the boat. but the weed eater engine cant sit that far forward.

should i trim the shaft and bring the prop closer to the hull. or just try it where it is?

im scared that in its current position the boat will not get up on plane







#2 txt killer Jul 18, 2011 09:09 AM

Dump the straight drive shaft out the back of the boat. That's way too much pitch. I see remains of the origional shaft log sticking out the bottom of the boat. That's what you should be using along with the flex cable and a telfon tube. You can get a new shaft log at Menards in the sink department. They'rs called semi rigid 3/8" sink connectors tubs? They're right next to the flexable ones. You also going to need to make new rail mounts to properly mount the motor and you need a strut with bearings for either a 1/4" or 3/16" shaft, a prop shat, a shaft drive dog, a furrel to attach the flex cable (silver solder to solder the furrel to the flex cable) a prop shaft and a rudder, a speed fin and trim tabs are optional. The motor is not much HP around 1 hp. But if it has a clutch it's ok. I use Homelite engines. More hp at 2 hp stock I find them super cheap.:D

#3 stompjrkz400 Jul 18, 2011 11:33 AM

yeah, im using the craftsman because its what i have. unfortunately the motor with the clutch is so long i cant even get it in front of the original shaft. i would have to shave so much of the top of the boat and the cg would be way off from the engine being so far forward

#4 stompjrkz400 Jul 18, 2011 11:35 AM

i have all the running hardware i need, rudder and turn fin, i dont have any trim tabs, and doubt i will need them with the setup

#5 wparsons Jul 18, 2011 12:02 PM

Are you using the rudder and turnfin from the 7.5cc outrigger? The turn fin is definitely the wrong shape, and the rudder is likely too small.

#6 Ron Olson Jul 18, 2011 12:14 PM

As far as the hull goes, it appears to be an old Radio-Active Hobbies hull from out of the Las Vegas area. They made them in 46" and (I think) a larger 52" version. RAH also made a Cat and Crackerbox.

#7 stompjrkz400 Jul 18, 2011 03:00 PM

my father brought all the boats home for me, there from nevada, so thats cool to know who made it atleast. the turn fin is from the boat. the rudder is from the rigger, its 4 inches in the water and 1.5 inchs front to back, getting that stuff figured out should be easy though, im just trying to ask how i can use the solid shaft in the boat. im not going to go buy a new shaft. unless i can find a setup cheap from a hardware store

#8 stompjrkz400 Jul 18, 2011 03:32 PM

i was thinking about a universal joint, i was also thinking about using a pivoting 3/8 ratchet u joint. but that would probably vibrate like a shizzle

#9 sleepwalker Jul 18, 2011 08:46 PM

Hull isn't a Radio Active. I have the 52" Eliminator which was later made from the molds of the Radio Active boats.It's a Prather hull they used for their Commander and 46' Offshore models.Some of the hulls are sold by Hyperformance Products http://hyperprod.bizhosting.com/commander_12.html

#10 carprigger38 Jul 19, 2011 12:43 AM

Do you still have the rest of the parts form the weedeater? If so use the flex cable from that for your drive.You can get a shaft from Zippkits.com for like 15 bucks,heck you can get the whole set up for less than 30 bucks if you shop around.itll save you a bunch of haste if yer serious about getting a boat goin. Theres nothin like the felling of driving something you put together!=)

See that drive in my avatar? I made that with a drill press and a TABLE saw!!! I thought I seen a drill press there in your garage,...LOL

Keep up the good work try what you can,if it doesn't work try again!!

#11 txt killer Jul 19, 2011 09:36 AM


Originally Posted by stompjrkz400 (Post 18793457)
yeah, im using the craftsman because its what i have. unfortunately the motor with the clutch is so long i cant even get it in front of the original shaft. i would have to shave so much of the top of the boat and the cg would be way off from the engine being so far forward

Fine a Homelite engine cheap around $20-30. The exhaust is out the side and would give you more room to move the motor back.;)

#12 stompjrkz400 Jul 19, 2011 11:23 AM

i have an hpi 1/5 buggy exhaust that im going to use, so i should be able to move it up alot closer, someone i know has a homelite engine that im going to ask him about, hes saving the motor to make a gas power blender... but ok ill give teh weed eater flex shaft a look, also, is this an ok setup?


i was thinking about just ordering that, but i work in a sheetmetal shop next to my house, so i might mess around with making my own flex setup first, only thing is i cant weld aluminum, so i have to either uses brass or steel.

#13 txt killer Jul 19, 2011 04:32 PM

I can't weld aluminum to so??? I tried those so-called aluminum rod kits that require mapp and they do work but over time the weld turns dark gray. I can mig weld and braze weld. If I need a aluminum part I machine it. That look like what you need. Im not totally convinced on composite? You might try Ebay for all Aluminum kits. The flex shaft you can use the one from a trimmer. All you need is the square end and cut it to length. Silver solder (Stay Brite) the brass furrel on the end and away you go. The shaft log you can get at Menards as I stated before and you can find the teflon tube liner online. Most important thing get a resistor spark plug or you'll have noting but headaches trying to fix the problem.:D A Homelite 25 cc engine is going to be far better than that craftsman. I recommend the st135 Bandit. No clutch but you really don't need one. It's nice but the clutch shoes are really crappy.

#14 stompjrkz400 Jul 19, 2011 10:26 PM

the motor pushed my rc car to 40 mph, so im just going to use it, like i said, its a budget build, just something to pass the time. i like the clutch because the motor idles awesome.
also i have a tuneable ehaust and after a little porting and cleaning its runs very good. im running good motox 2 cycle oil and 15 % nitro, is mernads a store, i dont have one around here. and i have a resistor plugs already

#15 wparsons Jul 20, 2011 07:59 AM

Hold up... you're running it on 15% nitro fuel and adding more oil? Glow (nitro) fuel already has oil in it... I wouldn't run it on anything but straight gasoline and oil mix, adding methanol/nitromethane will give you lots of headaches. It will attack the seals/lines/etc designed for gas.

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