Brushless Traxxas Blast - Few questions!

[Gopherboy6956]

Hey Guys -

I got my new motor and turn fins yesterday. Got them installed last night. Took it out today after work and WoW! that motor has some torque! I used my 25c 2s 4000mah Lipo with it , and it is very smooth and controllable.

I do have some questions though, as i might have to tweak some things. It would be AWESOME if anyone has some suggestions.

1. When it's running near full throttle, it leans to the starboard side - a lot.

2. It also wants to steer left, again quite a bit. It's controllable, but annoying. This is not a trim setting issue. Everything is set to neutral.

3. It will turn left ON A DIME, and usually at high speeds (Turn fins?) but it won't turn right worth a crap. I have to slow way down.

I can't figure this out, just by looking at the drag items (turn fins, water pickups, -they are all even) so any ideas?

I have linked a few photos so you can see my setup.

Interior - Hardware
Leopard 3650 Motor - 2450kv
Proboat 60A Esc
Stock blast servo
Traxxas 2.4ghz radio
2s 25c 4000mah lipo


Rear:








Thanks!

[Gopherboy6956]

Anyone?

[NorCalZ71]

Whats the temp on everything after 5 min? When I went single brushless on my villain I had same issues. It could be that the steering linkage is flexing from prop torque or that the prop is steering the boat. Or the prop is too large for the motor kv. Just my ameture .02 cents

Sent from my T-Mobile G2

[Gopherboy6956]

Whats the temp on everything after 5 min? When I went single brushless on my villain I had same issues. It could be that the steering linkage is flexing from prop torque or that the prop is steering the boat. Or the prop is too large for the motor kv. Just my ameture .02 cents

Sent from my T-Mobile G2

Thanks for the reply. My temps are so low on the 2s I haven't even measured them. They are barely warm to the touch. I think that it's very possible that the steering is driving the boat. Just hope to figure out how to change that, if i can. I guess narrow boats have this problem?

[newbie4life]

Yes this is an inherent problem with a narrow hull and the steerable drive.

[Gopherboy6956]

Yes this is an inherent problem with a narrow hull and the steerable drive.

Yep - Just went out and played with it and the 3s Lipo. I couldn't even get to full throttle, because it would torque steer soooo much left, that I'd have to steer right, which just about put the right side of the boat underwater. When i got back, i did a little investigation as to how much torque steer is has. It has, this much:

http://www.youtube.com/watch?v=PGipJjE-k7M&feature=youtu.be

Also - note - I did unhook the servo rod just to i could see how much it moved on it's own.

So, unless there are any awesome fixes besides going slow, I think I need a new boat / hull.

Any suggestions? I'd like to keep it toward the inexpensive side.

Thanks!

[NorCalZ71]

You may be able to fight it with a higher torque metal gear servo, an aluminum servo horn, and heavier guage push rod. But I think what may be causing the roll/steer is not the out drive turning but the prop causing the boat to roll which makes the rudder act as a turn fin lifting the boat sideways out of the water. I would try adding some trim tabs to maybe add some downforce on the side opposite the lift to counteract.

Sent from my T-Mobile G2

[newbie4life]

Remember newtons third law! The more force the prop puts to the water, the water pushes back just as much in the opposite direction. ie; the boat torquing to the right. Imo You need trim tabs.

[Heaving Earth]

Get a hull that can handle brushless power

[Gopherboy6956]

Get a hull that can handle brushless power

Any suggestions?

[Gopherboy6956]

And actually, which trim tabs do you guys recommend given the space i have?

Thanks!

[Heaving Earth]

A nice Df 26 is about the same size but can handle speeds in excess of 50

[Gopherboy6956]

A nice Df 26 is about the same size but can handle speeds in excess of 50

That looks pretty awesome. So, i'd just need to get a rudder change the drive method? Will the traxxas servo still work?

[Gopherboy6956]

Well, I'm giving the ol blast one more shot. Ordered trim tabs and a different prop. We'll see what happens!

[Make-a-Wake]

Your servo is too weak.................

Here's what i found intersting in your vid, your body energy field can make a motor jump...............