OJ racer

wait, wamf, do you mean that you lost the prop and shaft? I'm planning on modding one of these once I can save up the money, and I don't want that to happen.

Russ Williamson

Remember all; this little dude was not built to handle brushless motors, LiPo's, etc. It is fun to get the little Rio ripping across the water, but it will be more abusive on the drive and hardware system.

Have fun!
Russ

OJ racer

Russ, you guys should design a brushless Mini Rio, like a mini SV27. I know a lot of people are just doing that regardless of structural limits.

wamf

Yep it fell out. Before I replaced it I drilled the set screws to 6/32" and put loctite on the screws and cable end. I also glued a plastic bead to the cable so it can't fall out. It was my fault it fell out. I do recommend buying spare rudder arms as these seem to be very weak.
MikeV

smaerd58

My Feedback: (13)

Russ, Ok undrstood about it being small but what do you recamend to get more speed out of it and still keeping it brushed? Thanks,Rick

Nina Roses Dad

I think Russ already answered that one! ;-)

I''m looking forward to hearing from others if the stock esc holds up if you run the boat on a LiPo. If it''s the same circuit as the Reef Racer 2 (which it probably is), with only 1 FET switching the load to the motor, my guess would be "NO". The problem we have here is that there''s not a lot of room for a separate rx and esc inside this hull.

(My recent ESC meltdown with my Hammer, running it on just a 7-cell Nimh, makes me tread cautiously into these waters...)

My theory is that the stock 1100mah pack isn''t capable of delivering enough current to burn out the esc in the MIniRio, but that the motor is capable of drawing more current than the esc can actually handle, so as long as you stick with the stock battery, you''re safe. If you went with a 2-cell lipo (which is capable of delivering much higher current and has negligible voltage drop under load), you are going to have a problem.

I''m going to put my boat on the "dynamometer" and take some voltage & current readings, first with the stock 1100mah pack, then with a 2000mah pack (which is 6 full-size AAs, available from my aftermarket source) and then with a sub-c pack. It''ll be interesting to see how much more current the motor can actually draw from the sub-c pack and how much less the voltage drop is. That will give me an idea of whether I should even risk running the boat on a LiPo.

The "dynamometer" consists of the bathtub in our house, two panel gauges (volts & amps) installed through the top of a plastic tool case, and a couple of bungee cords to restrain the boat in case I lose my grip on it.

I just got the boat a few days ago and haven''t run it yet. The rudders look strong enough to me (sure, if you run over something they may break). The drive cable on mine looks like it''s going to grind away on the inside of the brass tube. The cable probably turns easier than the solid shaft, so there''s no doubt it helps the boat go faster.

wamf

I ran a lipo three times with the stock esc, no problem. There is a little more room than it looks like at first. I have a seperate esc and receiver in mine. When you get more power it helps to put some weight on the left side so it rides flatter and straighter. My rudder arm broke when I turned the rudder by hand. I have run mine about a dozen times.
MikeV

Nina Roses Dad

wamf - What''s your first BL motor and what''s the one that''s on its way?

wamf

I''m running a feigao 380s 2632kv with a cc Tbird 36 amp esc. I ordered a turnigy 3900kv from united hobby.It came today. This thing is plenty fast for me with the 2632 and still handles great. I don''t think I will put the 3900 in any time soon.
MikeV

wamf

Ran mine today on some relatively calm water, it is fast. I ran with a 1300 battery thinking lighter is better. Normally run with 2000mah. Lighter was a little faster but the boat was out of control, looked like it wanted to fly.
It was taking on lots of water, looks like it was coming from the drive cable. I''m glad i had siliconed my esc and had the rx in a balloon. The cable unwinds as it spins I assume this is to reduce water transfer but at high rpms it was not working. I found that a antenna tube (clear) fit the cable snug and tightly into the stuffing tube and may have been an improvement. I opted to make a wire drive instead. I used .047 piano wire sanded and clean on one end. Using a solder gun the cable easily came out and I inserted the wire, seems strong. I then used a short piece of antenna tube on the upper and lower end of the stuffing tube and glued a bead to the wire in case it comes out of the coupler. I will try it tommorow. FYI if you use a feigao motor you need to drill the coupler out to .125"
MikeV

wamf

Ran it today and only had a few drops of water inside. At one point it was capsized for 10 min while I waited for the wind to blow it back. It was to cold to wade. The shaft stayed tight and it all worked fine. I''m using some hextronik 1300mah lipo batteries from united hobby and they seem to perform well. The cowling doesn''t float so be sure to add a piece of foam to the inside.

airickf

You guys need to take some Video! and post on youtube! I''m thinking about getting one of these but would like to see how they run modded.

VIDEO PLEASE!

wamf

I''ll get right on that
For me it''s buy the boats or buy the camera.....I''m buying boats.
MikeV

Grimracer

Do a check for me.. ALL cables to this point have been left lay (correct for the boat). I just grabbed a few more and checked them.. Again left lay...

Left lay tightens the cable as it runs..

Let me know.. if in doubt take a pic and post it.

Thanks
Grim

wamf

On both the cables I have/had they un wind as I twist the prop counter clockwise. Which I guess means that they tighten when the motor spins them. I think backwards a lot must be the beer. That at least explains the massive water content of my boat after a short run. Or does it? No water with wire.
MikeV

Grimracer

OK cool.. Im not sure but it might be the way you are lubing the wire?

I tryed to get it to be a wire drive right from the start but most Music wire can rust real bad when not taken care of.. Could be that alot of users will never lube the drive system.

Grim

Grimracer

One way to determine if you have the right cable is to hold your left arm straight out in front of you and spread your hand wide.. Take your right arm and LAY it over the top of your left again taking this hand and spreading your fingers wide.. Touch your pinkies and this is what a left lay cable looks like from the top.

Your right arm is angled and your left is straight out.. when viewed from above this is left lay.

Try it.. it works

ROCK ON

Grim

wamf

You were/are right. I was thinking wrong. However the boat didn't take on water until I went BL. The motor is a bit heavier than stock maybe that's why. It doesn't take in water with a wire. I think the design of this boat is great. It flies and stays stable. Doing all that without turn fins or trim tabs. Turn fins would probably help at high speed. The boat is a blast
MikeV

Grimracer

I have made quite a few sets of fins and tabs.. both work great on the boat.

Grim

wamf

If you had a extra set of turn fins for the mini rio I think I could hook you up with someone to try them
MikeV

wamf

Those same people will never know that anything is rusted.
mikeV

Nina Roses Dad

That rudder arm is FLIMSY. The rudder arm kit should include TWO rudder arms for the starboard side! I'd pay $2.29 for that instead of $1.79 for one of each!

wamf

I told you I bought three sets. I'm still using the original one. It broke in two places but I glued two two small peices of wood one on top one on the bottom with ca glue and it is still working. Looks like crap though.
MikeV

Nina Roses Dad

Hobbico comped me 2 pr of rudder arms. They arrived in the mail over the weekend. They don't tell you that the hole for the setscrew needs to be bored out a little before you drive in the setscrew, otherwise you will strip the hex socket in the setscrew before it ever hits the flat spot on the rudder shaft. I stripped mine before I got it tightened all the way down, so on today's two runs the boat's starboard rudder had play in it & kept flopping around and the steering was really wacky. You'd begin turning with the port rudder and if the stbd rudder flopped the same way the boat would suddenly spin out or if it flopped the other way, it would cancel what the other rudder was doing. Because the rudder leads the shaft instead of trailing it, it flopped back & forth at will, the stern of the boat was sitting low in the water most of the time and the boat couldn't accelerate up to speed.

The link on the end of the steering pushrod sort of looks like a little ball joint or tie rod end, but it doesn't rotate freely the way you'd intuitively think it would. On mine, the screw was threaded right through the rudder arm and the nut was screwed down pretty tight. I think it snapped the first time I blipped the steering on the tx. When I installed the new arm, I first used a 1/8" bit to bore out the hole in the rudder arm where it connects to the ball joint. If you try to ream the hole to a larger diameter, you will probably crack the plastic. Now it rotates freely on the linkage rather than binding up. Just reaming out the hole a little bit and not fully tightening the nut isn't an option, as the nut will eventually loosen and you run the risk of losing it and the screw that ties it all together and then having to retrieve the boat because you've lost your steering.

On the replacement rudder arm you'll also need to bore out the other hole where the arm connects to the link that controls the port rudder.

Anyway, once this all gets sorted out, the little boat is going to be a lot of fun.

wamf

I tapped all set screws to 6/32" a little bigger socket. I was stripping all the 1.5mm ones.
MikeV