1/10 scale setup problems

[rat350r]

I have been working on getting a couple 1/10 scale hydroplanes trimmed out for a while now. One is a Miss Thriftway U-60 and the second is a modern Miss PICO American Dream U-100. To date I have been through two Aquacraft 1800Kv motors and two older DYNM3835 1500Kv 6-pole motors. I am using SeaKing 120A ESC and two 6000mah 2S packs in series. I have been running Octura X447 two-blade prop and several smaller props trying to get the boat trimmed out.

After several outings, trying to get things setup all I am accomplishing is burning up motors. The best speed I have been able to get is in the mid-30s. From what I have been seeing that is quite slow. So my questions are,

What should a 1/10 scale hydro weigh RTR?

What depth and angle should the prop be? Prop strut exiting the bottom of the hull.

What should the CG be?

What size range and manufacturer are the preferred props?

Are the props heavily modified regarding cup and blade profile.

What are suggested motors 36mm 60mm can size?

What should the hull ride attitude be? I feel that my boats are running way to wet.

I know I have left out details so please feel free to ask any questions on my setups.

Thanks
Bruce Price
IMPBA D-12

[Tetefroid]

There are some guys on here with awesome knowledge about these things..I'm not that guy. But as a rule of thumb I can tell you, the lower the voltage = greater the amps, and amps creates heat and heat burns up winding's and can unsolder things...

[Tetefroid]

Great looking Pico btw!!

[JimClark]

A good starting spot for CG should be about 1 to 1.5 inches aft of the back of the sponson.
Running wet and heating up the motors is not good as you have found out. What kind of shaft do you have?
Tell us your weight and show pics of the rudder and strut setup.

[rat350r]

Jim,

both boats have 3/16 flex shafts. The Miss Thriftway is about 8 Lbs 3 Oz ready to run and the PICO is just under 9 Lbs. As for pictures I have some shots of the PICO but no pictures of the Miss Thriftway but both are basically the same.

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[leonard feeback]

Hi Bruce, Jim will probably have pretty much the same advice. Your flex shaft should be 150 flex, the 3/16 is way to big. putting a lot of drag on the motor. Also looks like the motor and flex shaft aren't lined up, at the coupler there is a bend, if so really hard on the motor. Probably why your burning up motor and esc's. Your turn fin should have around a 10 degree slant on it. The 447 is a good starting prop to get the bugs worked out the boats. The 442 or 445 will also help keep the motor rpm's up. Don't lug the motor down.

[rat350r]

I have been going over the Miss Thriftway and installed a .150 flex shaft. I have also raised the strut up from its original depth of 1 1/8" to 7/8" in an effort to raise the bow and loosen the boat up. I think I have an X445 prop to try, if not I will go with something a little smaller then an X447. I am also going to see if I can move the batteries back to another position in an effort to move the CG back to around 1 1/2". I have one Aquacraft 1800Kv motor left.

I have two fried AQ 1800Kv and two fried DYNM3835 1500Kv motors that I need to do something with. Does anyone have any suggestions on what to do with them or any suggestions on replacement motors. I am not ready to through in the towel on these 1/10 scale boats yet. Thanks for all the responses and advice.

Bruce Price

[rat350r]

I was able to run the Miss Thriftway yesterday afternoon. For the first time I am seeing progress in the right direction. The Aquacraft 1800Kv motor survived with no signs of overheating. The boat was quite loose and for the first time in its history actually flipped when I turned the boat into the wind and wasn't quick enough to catch it before it went airborne. I feel the combination of going to a .150 diameter shaft freed up the load on the motor and re-positioning the batteries and raising the strut freed up the boat lowering the drag on the hull. I do not have any idea of the boats speed but I feel it was much faster then before just by the way the boat was dancing on top of the water.

I have one more weekend of Test-N-Tune before the last race of the year here in D-12 in Maryland. I do not know if we will have enough boats signed up in 10 scale FE for a race but I think I will have one boat ready.

Thanks
Bruce

[klloyd67]

I was able to run the Miss Thriftway yesterday afternoon. For the first time I am seeing progress in the right direction. The Aquacraft 1800Kv motor survived with no signs of overheating. The boat was quite loose and for the first time in its history actually flipped when I turned the boat into the wind and wasn't quick enough to catch it before it went airborne. I feel the combination of going to a .150 diameter shaft freed up the load on the motor and re-positioning the batteries and raising the strut freed up the boat lowering the drag on the hull. I do not have any idea of the boats speed but I feel it was much faster then before just by the way the boat was dancing on top of the water.

I have one more weekend of Test-N-Tune before the last race of the year here in D-12 in Maryland. I do not know if we will have enough boats signed up in 10 scale FE for a race but I think I will have one boat ready.

Thanks
Bruce


This is great info as I prepare to get my U-3 1/10 Scale wet, I will be about 7 lbs, planning on a x447, 2S setup with 1600kv, 1800kv and 2030kv options. I was planning on a 3/16 shaft, I will go with .150.....would piano wire drive or .130 be tough enough?

[Moonie]

Bruce. I could help you right at the pond.

[rat350r]

Moonie,

I expect to be at the pond on Saturday with a couple of boats

[leonard feeback]

Bruce, glad you replaced the 3/16th cable. I run my batteries forward the motor. You want to run the boat with not much weight on the prop. Less weight allows more rpm's, rpm's lets the motors run cooler. Mine do. I'm running a 447 with 1500 kv motor, runs fine. Nice to hear the boats starting come around. batteries up front will help with blowovers also.
Leonard

[rat350r]

All,

Sorry I haven't gotten back with responses to the latest posts.

klloyd67,

A piano wire drive is the accepted method for vintage hydro's in NAMBA with a straight shaft from the exit of the hull to the strut. Modern Hydro's can use a flex shaft with a bend in the shaft under the hull. I do not think a .130 flex would hold up.

You should check with your local organization to see what rules they abide by regarding shaft arraignment and race direction. We here in IMPBA District 12 on a local level allow flex shafts in both classes. One other thing to keep in mind is the direction the boat is raced in. The NAMBA rules have 1/10 scale FE run in a counter clockwise direction turning left. To do this you will need the proper flex shaft to spin the prop in a clockwise direction to aid in turning the boat. Again here locally we have decided to run clockwise and use a flex shaft wound to spin the prop in a counter clockwise direction. Also the turn fin will need to be on the proper side to turn left or right along with the correct rotation prop.

Leonard Feedback,

Thanks for the response. I will experiment with CG location to see if I can lighten up the stern of the boat. I hope to do some more testing this Saturday.

Thanks for the input
Bruce Price

[leonard feeback]

Bruce, I run counter clockwise {NAMBA} I also run a flex cable and it is straight from exit of bottom to strut works fine and can make adjustments if needed..
Leonard

[klloyd67]

I will be running counter clockwise hoping 1/10 scale FE gets going again one day in AZ

[T.C.]

Isn't everything going to change when you set up for counter clockwise ?
I don't know if there are as many props available and the flex shaft would be different.
I ask this cause your boat looks to be setup for clockwise running.
T.C.