DF 23 Sniper new @ OSE, Yeah Baby!!

[ray schrauwen]

Run 3 of the day with the DF Siper.
Rather than wait for a new battery to come, I built my own pac. I had a few 5000, 40C, 4s pacs that were brand new. I just CAREFULLY, cut out one of the cells making it a 3S, 40C, 5000 mAh pac for the Sniper. Weight of the pac only 418 grams. Pics show the 3S next to the factory 4s pac.

Charged the battery and ran the Sniper, getting about 1/2 lap before the Deans on the Eagle Tree came unsoldered. Even with very short run and certainly no where up to speed, you can see the Eagle Tree Data. (I left off the Eagle Tree Pwer Panel).

GPS speed 40 MPH even it a very short distance and not full tilt. The motor only up to 92.4F and I used less than 10% of the battery capacity.
Note also the Amps and RPM. (I have his calibrated for th Eagle Tree brushless RPM sensor as a 2-pole motor, could I be wrong?) I will re-do the connectors and save the next run for the future. It's cocktail time............

I don't see where you posted what prop you are running.

This is a major factor, do tell!!

[questtek]

STOCK carbon/plastic prop and stock 3 mm drave shaft. (Believe ist is a 434) Next phase is to make a series of runs with different props. I wanted to make sure the new battery would handle things and it appears it may.

[ray schrauwen]

STOCK carbon/plastic prop and stock 3 mm drave shaft. (Believe ist is a 434) Next phase is to make a series of runs with different props. I wanted to make sure the new battery would handle things and it appears it may.

You should find that you will waste less power with a metal prop compared to a plastic one and your speeds will increase too.

I thought you were still using a stock prop. Get rid of that nasty thing.

Now we will see some pretty numbers.

Delta Force website says they use a 42mm 1.4 pitch plastic prop.

@ 60,000 rpm that prop is just wasting energy and bending to all hell.

[ray schrauwen]

Actually the Stub shaft is a 4mm shaft stepped down to .125" with a USA 5-40 thread on the end and a .130" flex cable.

Pretty whacky to use both Metric and Imperial but, hey your car is the same way.

[westbeach]

I picked up some cnc props to test on the sniper, should be here any day now. Also ordered a couple of outrunners to go along with the test.

[questtek]

You should find that you will waste less power with a metal prop compared to a plastic one and your speeds will increase too.

I thought you were still using a stock prop. Get rid of that nasty thing.

Now we will see some pretty numbers.

Delta Force website says they use a 42mm 1.4 pitch plastic prop.

@ 60,000 rpm that prop is just wasting energy and bending to all hell.

Morning run with brass 435 prop
Using the giant 5000 mAhr, 40C, 3S pac my first run terminated with the Deans coming unsoldered and the servo breaking from the mount.

I included a pic of the servo. Note the 4 holes in the mount but there were no screws in them and when making turns in excess of 40 MPH it ripped the servo mount from the base. I re-epoxied it and now added screws to insure this will not happen again. RECOMMEND CHECKING YOUR SNIPERS AND DOING THE SAME.

Resoldered the Deans connectors, recharged the battery and run #2 of the day is shown on the Eagle Tree Display on my laptop. Amps 120 (and this may be the max the Eagle Tree reads but I am thinking it is MUCH higher.) Speed is 44 MPH and that was consistent for all 3 speed passes. Temp of the motor up to 149F, and I used about half the energy in the 5000mAh pac.

There is a problem with the Eagle Tree and RPM. The pic of the display shows the max HOWEVER, the actual RPM when you go thru the runs step-by-step is 30,994 RPM. Why the max value of 63,000 rpm is displayed as max is a mystery to me. Stepping thru the data the highest RPM was about 32,000 which is very realistic.

Amazing I achieved this speed with an inrunner with a badly bent shaft. New outrunners have not come in so I will keep playing with this junk motor till they do.
I also have a 536 brass prop that may even get me faster. However I cannot put it on unless I change the endire drive shaft since the current one is too small for this 1.5 pitch, extended length prop. The nut just will not go on!

I am switching to 6 mm gold bullet connectors on everything and using a different Eagle Tree Logger than can handle 150 AMps because that is what I think I am pulling, not just the 120 amps displayed on the std logger. I may even have to put in a Seaking 180 ESC that I have available.

The Sniper is one great boat to experiment with!

[befu]

Wow

Wow, that is some power Questtek.

Did you look at the 2d graph of the data also? I am wondering what the amperage vs. speed curve looked like.

3s at 120 amps is a ton of power! At 3.5v per cell, that is around 1300 watts! This is a 23" boat, right? Same as they are talking about in this thread correct? Wow! And you are getting a peak of 44mph on that setup. could you post the 2d graph? Or, if not, would you email me the data file and I could look at it?

Thank you, keep up the fantastic testing!

Brian

[questtek]

Wow, that is some power Questtek.

Did you look at the 2d graph of the data also? I am wondering what the amperage vs. speed curve looked like.

3s at 120 amps is a ton of power! At 3.5v per cell, that is around 1300 watts! This is a 23" boat, right? Same as they are talking about in this thread correct? Wow! And you are getting a peak of 44mph on that setup. could you post the 2d graph? Or, if not, would you email me the data file and I could look at it?

Thank you, keep up the fantastic testing!

Brian

YES, This amazes me also. The SNiper is one of the best FE's that I have run along with the Insane 30" Hydro. Your are correct in the watts, amazing expecially with a motor with a bent shaft.

I included a pic of the 3 motors:
Stock Brushless
Upgraded Brushless that I just installed
Inrunner with Bent shaft I have been running.

In terms of the data, I just keep the screen shot generally or otherwise I would have way too much data. I will see if I kept this log and if so do a 2-D graph or send you the raw data. If not, I will send you the data from tomorrows run with the new outrunner.

[questtek]

Wow, that is some power Questtek.

Did you look at the 2d graph of the data also? I am wondering what the amperage vs. speed curve looked like.

3s at 120 amps is a ton of power! At 3.5v per cell, that is around 1300 watts! This is a 23" boat, right? Same as they are talking about in this thread correct? Wow! And you are getting a peak of 44mph on that setup. could you post the 2d graph? Or, if not, would you email me the data file and I could look at it?

Thank you, keep up the fantastic testing!

Brian

I did save the data from the 44 MPH Sniper run and have two plots in the attached pics. One is amps vs speed and the other GPS course plot. How do YOU intrepret the Amps vs Speed curve?

[questtek]

Ran the Hobby King motor this morning
Here is the link to the motor I used:
http://www.hobbyking.com/hobbyking/s...dProduct=11177

First run on a 2C pac that produced a max speed of 25 MPH, identical to the stock ste-up that comes with the Sniper. Pulled 60 amps at about 8 VDC and the motor temp up to 143F max. Not bad for an $11 brushless outrunner but nothing to write home about.

Second run with a 3s, 5000mah, 40c pac
Max speed 34 MPH (That is 10 MPH SLOWER that with the previous inrunner with a bent shaft)
I was pulling 963 watts from an outrunner rated at 600 watts. Hi Temp at the end of the run was 184.9 F and the little outrunner survived. Max RPM was 43,859. I also recorded a max amp draw of 108! That SeaKing 90 ESC is incredible and I would want nothing smaller.

Tough little motor but these are way too small to really get the Sniper going. I am now looking into one of the Tenshock motors. I will retire the Hobby King motor for now.

[BILL OXIDEAN]

Are the hulls light?

[ray schrauwen]

Are the hulls light?

It would make an excellent N1 mono.

Light compared to what?

[ray schrauwen]

Ran the Hobby King motor this morning
Here is the link to the motor I used:
http://www.hobbyking.com/hobbyking/s...dProduct=11177

First run on a 2C pac that produced a max speed of 25 MPH, identical to the stock ste-up that comes with the Sniper. Pulled 60 amps at about 8 VDC and the motor temp up to 143F max. Not bad for an $11 brushless outrunner but nothing to write home about.

Second run with a 3s, 5000mah, 40c pac
Max speed 34 MPH (That is 10 MPH SLOWER that with the previous inrunner with a bent shaft)
I was pulling 963 watts from an outrunner rated at 600 watts. Hi Temp at the end of the run was 184.9 F and the little outrunner survived. Max RPM was 43,859. I also recorded a max amp draw of 108! That SeaKing 90 ESC is incredible and I would want nothing smaller.

Tough little motor but these are way too small to really get the Sniper going. I am now looking into one of the Tenshock motors. I will retire the Hobby King motor for now.

What prop? Did you try more than one prop?

[befu]

Second run with a 3s, 5000mah, 40c pac
Max speed 34 MPH (That is 10 MPH SLOWER that with the previous inrunner with a bent shaft)
I was pulling 963 watts from an outrunner rated at 600 watts. Hi Temp at the end of the run was 184.9 F and the little outrunner survived. Max RPM was 43,859. I also recorded a max amp draw of 108! That SeaKing 90 ESC is incredible and I would want nothing smaller.

Are you sure of these numbers? And this is the 23" boat correct? Your power draw seems way to high. I am running my 24" mono with a turnigy 3650-2300 motor pushing a 38mm plastic prop. Just a slow sport setup, but on a 3s-4400-20c battery setup it is running a consistent 34mph. PEAK amps is 53, but it averages out to the low 30's when running full throttle. That is about 370 watts for a 24" mid vee mono to run 34mph. 963 watts is a lot of power in that small boat to only get 34 mph. That is around mid 80's for amperage! Even if that is only peak, that is really high.

Just looked at that motor. 4400kv is pretty high for 3s, almost 50,000 rpm. I am wondering how loaded down it is. What rpm under load is the eagle tree saying and what prop are you running?

Weather is supposed to be decent this weekend, I will try to get my boat back out and see what I can get out of it. Might have to put in a new speed control, because it only has a 35/40 hobby king SS ESC in it.

I like the look of this little boat and I am curious to what others are getting out of it. Keep posting data, it is interesting.

Brian

[questtek]

Attached pics how the Eagle Tree Data. I have 3 different V3 loggers and used each one of them on the boat. I agree with you and that is why I post the actual screen shots of the Eagle Tree data dump direct from my laptop. YES, the 4400 KV is WAY too high to run on 3S but if you go to the HobbyKing site for this motor (see the link in previous post) you can see it says 2-3 LiPo pacs.

The pics show one run with 2S and two runs with 3s from the Eagle Tree.

I was not happy with these outrunner motors in the Sniper and put in the inrunner to get back in the mid-45 MPH range. We did use these same motors in a Radek designed/built carbon fiber/kevlar dual cat yesterday and the speeds were blistering.....for about 5 sec till it did some incredible airborne flips. I did not have an Eagle Tree on it (no room and CF meant no GPS signal), but imagine the motors each were pulling 600-900 watts each. There was so much power it sound like a jet turbine and actually broke the flex shaft in half. It was running on 2200 mHr 3s lipos for each motor. You can see the post under the video forum and actually see a video of this run.