Liberty's high speed RC OutRigger boat build thread

[Doom!]

Sounds like you need to send the family on vacation so you can get some garage time.

 

[AIan]

I was watching the guys from Flight test on YouTube doing an airplane from a 3D printed design. The interesting part was the filament they were printing with, it was call LWPLA. Basically Light Weight PLA and I thought of your build here. Here’s the video I saw. I also liked the way he connected the fuselage parts together with the wires in little tubes.

 

[LibertyMKiii]

I was watching the guys from Flight test on YouTube doing an airplane from a 3D printed design. The interesting part was the filament they were printing with, it was call LWPLA. Basically Light Weight PLA and I thought of your build here. Here’s the video I saw. I also liked the way he connected the fuselage parts together with the wires in little tubes.

Wow that is really interesting and gives me some ideas for ways to improve when I do my next design. I like that method of the metal rods inside for alignment and strength. I'll also have to give the LW-PLA a try.

 

[AIan]

Glad if I could help!

 

[LibertyMKiii]

Tested out the XLX2 for the first time yesterday in our 42" Deep Vee boat.
I only ran it on 4s and glad I did. I had modified the 1.4 pitch 47mm prop by sharpening it and added a little more curve to the prop. My estimate is that it is now a 1.63 pitch prop.

I would get the boat up on plane which takes about 10 to 15% throttle and then within 1.5 seconds get to full throttle. Only held full throttle for around 3 seconds as I could hear it easily maxed out the rpms for that voltage. I was purposely being a little hard on the system to see what sort of loads it sees and what sort of temps it reaches.

The result was the ESC stayed at ambient temps, barely broke a sweat in amperage, and went 48mph on the GPS. I continued to make 6 full speed passes all within 60 seconds and the ESC only picked up 12 degrees F.

This meant the boat would do 80+ on 8s, but this deep vee would blow over guaranteed. It is just too much for this type of hull. I'll put the Seaking 180a back in and find a cheap leopard motor for this 42" Deep Vee.

As far as I can tell this power system should have no issues going really stinking fast in the custom rigger

 

[LibertyMKiii]

Small step forward on the project.
I got a wire drive setup made for this build, really nice quality and all custom made to my specs.

Today I cut out the hatches so I can begin mock up of the components. It will be snug in there...
TP4070 (40x107mm)
Castle XLX2 ESC
Servo
2x 4s LiPos to run on 8s.

 

[jkflow]

Do yourself one favor and do not use that motor mount, use the one where you can remove the motor from the top.
Yes, it's a nice mount and works great, but switching anything in the future is a pain. Learned the hard way as well.
https://www.offshoreelectrics.com/proddetail.php?prod=ose-83354

 

[LibertyMKiii]

Do yourself one favor and do not use that motor mount, use the one where you can remove the motor from the top.
Yes, it's a nice mount and works great, but switching anything in the future is a pain. Learned the hard way as well.
https://www.offshoreelectrics.com/proddetail.php?prod=ose-83354

That is a good point given the confined space.
Thanks!

 

[LibertyMKiii]

Looking to re-visit the project soon. Starting to itch for some RC boat speed!!!
Also, someone finally started a GPS-based speed list for the RC boats.

https://gpsspeedrun.com/speedlist/speed-list-2022

 

[LibertyMKiii]

Testing some theory lately and sharing knowledge from car speed running over to boat speed running.
I had only captured data with the XLX2 in my 42" vintage mono, but found some good data already.

The big powerful motor and ESC could power through and make any of the 5 props tested net about the same mph, but the other data shows where a correct prop makes a difference.

I plan on doing some 6s test runs next. These were all on 4s.
TP4070 1700kv XLX2 and a single YoWoo 4s 6Ah pack.

The x645 is a Dasbota prop and the performance and acceleration is great, but more so the efficiency is off the charts good! (visible in the amperage draw and rpms)
All props were sharpened, balanced, and polished.

I suspect with more RPMs on 6s these props would spread further in MPH and amps.

 

[AIan]

I like that site for speed running with boats, it made me want to get my tfl pursuit up to speed again lol my top was 68mph on 6s and burnt up the motor lol newbie mistake of going full throttle off the rip oppsy. Now I have a 2650kv motor rated:

hopefully I can run 4s–5s w no problem

 

[LibertyMKiii]

I like that site for speed running with boats, it made me want to get my tfl pursuit up to speed again lol my top was 68mph on 6s and burnt up the motor lol newbie mistake of going full throttle off the rip oppsy. Now I have a 2650kv motor rated:View attachment 242273
hopefully I can run 4s–5s w no problem

I would think that KV would be good for a high speed run.
Just have to make sure you do 1 and then let it cool down pushing it to the limits like that.

 

[AIan]

Yup I hope so, but I’m trigger shy on it after burning the first motor so easy, but I believe it was my lack of experience that caused it more than anything. I’m gunna give the cooling lines a good go through, re-polish the prop, sharpen if necessary. And try a few speed runs now that the lake I live on is star to cool down now, the water has been really warm this year so far.
but I’d love to compete in some sort of list like that one you showed. I’ve only seen one other guy run. Cat on my lake before, but at least ther was one other. Lol
pleanty of space and it has very calm days, even local wildlife like my backyard

 

[LibertyMKiii]

Yup I hope so, but I’m trigger shy on it after burning the first motor so easy, but I believe it was my lack of experience that caused it more than anything. I’m gunna give the cooling lines a good go through, re-polish the prop, sharpen if necessary. And try a few speed runs now that the lake I live on is star to cool down now, the water has been really warm this year so far.
but I’d love to compete in some sort of list like that one you showed. I’ve only seen one other guy run. Cat on my lake before, but at least ther was one other. Lol
pleanty of space and it has very calm days, even local wildlife like my backyard
View attachment 242415View attachment 242416

That looks like a great spot you have there!
Just remember that speed running a boat is no different than speed running a car. If you are pushing that motor hard it is one pass and then needs a cool down.

 

[Camaroboy383]

Yup I hope so, but I’m trigger shy on it after burning the first motor so easy, but I believe it was my lack of experience that caused it more than anything. I’m gunna give the cooling lines a good go through, re-polish the prop, sharpen if necessary. And try a few speed runs now that the lake I live on is star to cool down now, the water has been really warm this year so far.
but I’d love to compete in some sort of list like that one you showed. I’ve only seen one other guy run. Cat on my lake before, but at least ther was one other. Lol
pleanty of space and it has very calm days, even local wildlife like my backyard
View attachment 242415View attachment 242416

Always remember, a calm water, (glass), is slow water.. ...

 

[LibertyMKiii]

Always remember, a calm water, (glass), is slow water.. ...

Luckily it is never not windy in Texas

 

[jkflow]

Actually, consider that we barely have the prop in the water and waves are a killer, even ripple must be tiny which actually makes it flat water. Might have a little more resistance but at least the prop stays in the water.

 

[Camaroboy383]

Actually, consider that we barely have the prop in the water and waves are a killer, even ripple must be tiny which actually makes it flat water. Might have a little more resistance but at least the prop stays in the water.

Wind ripple and light chop will be the fastest water you can run on.. it's not about prop characteristics in this instance, it's about the Bernoulli effect on the hull itself, and being able to free itself from the suction...

If there are waves large enough to unhook the prop to the point it prohibits speed it's usually time to pack it up...

 

[LibertyMKiii]

Ordered a few ABC props from Off Shore Electrics. These ABC props are waaaay more aggressive than the octura props. I hear people say they pickup 10+ mph going to ABC props so it will be interesting to try them!

They all need sharpening, balancing, and finishing.... but loving the way they look already!
The 18 series seemed to have bad markings on top for the prop so I wrote it on the blade till I can etch something more clear on them.

 

[AIan]

Wow they definitely have a huge curve on that front edge I balanced, sharpened, and polished my octura props and those look impressive!
I might get a couple