First FE build

[JohnRussell]

So I finally finished my first FE build. I have a few questions.

The boat is a TS3 with O.S. Lower, AquaCraft Brushless 36-56-2030kv Motor, Seaking 90amp ESC, TFL X444 prop.

first question is am I pulling to many amps? Peaks around 170-180 it's rated for 90 continuous and 180 burst but I don't want to burn it up.

What is to hot for a 4s 5000mah battery? It got up to 140deg

The boat handles great thanks to all the info found here and OSE it accelerates wicked fast and tops out around 42mph so I don't feel it is over propped but like I said this is my first FE build and I don't want to burn up the ESC or the boat.

Thanks for any input. Attached is a picture.

 

[Chilli]

Very nice first build John. Congratulations. I had a TS3 and loved the way it ran. 140 is about the accepted max (I like mid 130's) but on an outboard out in the open she probably cools off a bit faster after you bring her in than an inboard application. So you probably are stressing the motor and ESC. How long are you running her and how far down are you running the packs? FE boats are all about managing heat so you'll probably want to either shorten the run time or prop down a bit. I ran a Grim Racer 42x55 on my TS3 with a similar set up except for the ESC. That was for heat racing where we rarely run more than thee minutes. Another option includes setting your boat to run a little looser (a little positive or up in the prop angle..... or sliding the outboard own a touch). This will increase speed and lower temps. But it may affect your handling negatively. If she starts to blow over or hook in the turns, go back to the original setup. if you change the prop you may also have to play with the setup a bit.

 

[lohring]

We run that setup with a Turnigy Marine 120 ESC. Below is a graph of a P spec test from the beginning of the class. These days we run bigger props than the X448 and pull around 120 amps average. The Turnigy ESC has a burst current rating of 240 amps which is why it does so well.

Lohring Miller

 

[RaceMechaniX]

I would try to keep the average amps below 100A if you want longevity. For heat racing 120A is about the limit for 6 laps and not much more. Most of my P-ltd set-ups are around 90-95A during a heat race.

TG

 

[JohnRussell]

Very nice first build John. Congratulations. I had a TS3 and loved the way it ran. 140 is about the accepted max (I like mid 130's) but on an outboard out in the open she probably cools off a bit faster after you bring her in than an inboard application. So you probably are stressing the motor and ESC. How long are you running her and how far down are you running the packs? FE boats are all about managing heat so you'll probably want to either shorten the run time or prop down a bit. I ran a Grim Racer 42x55 on my TS3 with a similar set up except for the ESC. That was for heat racing where we rarely run more than thee minutes. Another option includes setting your boat to run a little looser (a little positive or up in the prop angle..... or sliding the outboard own a touch). This will increase speed and lower temps. But it may affect your handling negatively. If she starts to blow over or hook in the turns, go back to the original setup. if you change the prop you may also have to play with the setup a bit.

Chilli, thanks for the complement and the info.

This was literally the second time in the water. To answer a couple of your questions, I ran it probably 5 to 7 min just a guess.

The pack was down to 23%

As far as rigging, height and angle set exactly as the TS3 instructions suggested. However, I will try as you suggest and see how it runs.

 

[Chilli]

5-7 minutes might be a little long for that prop and as Tyler pointed out your amps are too high. Instructions that came with the hull are for a nitro set up but they are still a good starting point. Weight, CG and Prop choice will dictate final adjustments. Get out to the pond and play with it. Try to keep the packs above 30%. It will increase their life span also.

 

[Kris Flynn]

I would go the 42x55 abc/grimracer to start and the m445 when you are ready ;-)

 

[JohnRussell]

Thanks, Chilli and everyone's help. I will get the boat back in the water tomorrow. I have a few other prop's to try.

 

[Doug Smock]

There is some good stuff here John. Check it out when you have a minute.

http://forums.offshoreelectrics.com/showthread.php?48263-P-Limited-Tuning-Tips-by-David-Newland

 

[JohnRussell]

Thanks Doug!

Ok I finally got the Eagle Tree e-logger figured out.

Max Amps - 129

Max Batt. temp - 158

Max Speed - 40.5mph

Total mAH - 4669

After reviewing the timeline the average is about 95amps the biggest peak of 129 was at 16mph which I think may have been when I hit #4 buoy and flipped and the motor was under water. I cut down an x445 and I will try that and see what the Amp load looks like and go from there.

 

[Chilli]

Shorten your run time a bit. You're burning a bit too many mAh and the battery temperatures are confirming it. This will shorten your battery life and stress the ESC. If you are planning on racing, simulate a heat by doing 7-8 laps, bring her in and check your temperatures to make sure everything is under 140 (capacitors usually get a little hotter). The longer you run, the more heat builds up so running for 5-7 minutes was not a good indication of whether your set up was good for a heat racing. Often when when someone asks for prop suggestions for a given set up they are asked whether it's for racing or sport running. The sport prop will always be smaller/less pitch because the run time will be longer. Getting the most out of your set up for racing is all about managing heat. Let us know how you make out.

 

[JohnRussell]

Thanks Chilli, The goal is to race the boat. I ordered a bunch of props to test. I haven't raced since the mid 90s and I can't wait to race again now with my son.

 

[Chilli]

Cool. I started with my son five years ago. He's going to be seventeen in a few months and we still race together. What part of the country are you at??

 

[JohnRussell]

I'm in North Florida near Tallahassee. There aren't any clubs near here so I am in the process of starting one. We just had our first club meet this past Sunday.

 

[Chilli]

Good for you. We can always use more proactive people in the hobby. Though no clubs are close to you, you're in the heart of tunnel country. Let us know how your testing works out.

 

[Frank Wayland]

A guy in our club race that boat, similar gear, and whupped hiney! It really handled well. Beautiful paint job John!

 

[JohnRussell]

Thanks Frank. I like your VS-1 as well.

 

[JohnRussell]

Will do Chilli, I am going to get it back in the water Sunday and if I can figure out how to post a video I will do that too.

 

[JohnRussell]

So I figured out why the amps were so high. I had a cold solder joint on the ESC connection one off the wired pulled out of the EC5 connector fairly easily. I cut it off and soldered on a new one. Sunday turned out to be a good day at the lake for the most part.

After reading the article that Doug recommend great article by the way I went to the lake with I good idea of what I wanted to do.

Ran the boat for 60sec at WOT With the same prop as above. Temperatures with the infrared were 85deg Motor, 86deg Battery, and 108 for the ESC, mAh 1000 according to the elogger.

I played with a bunch of different props some I cut and some borrowed and have a fairly good idea of what needs to be done to be ready for race day.

Thank all of you for your help.

,https://vimeo.com/119259791

 

[JohnRussell]

Oh and the control rod fell off at the end of the video!