Infraction Another Limitless Type Thing

[GMballistic]

This set are heading to the bin as the sidewalls have serious scuffs from the flip. I have another new set of Hoons to do a few runs on before I put on the foams.
Stabilisation is next though as this loose setup on foams would be impossible. Once stable I will change the Neu mtotor for an 8s kv motor rather than this 12s motor.

Nice pass Darren.
What foams are you planning on running eventually then?

I've got SP Racing 50 shore foams on my Limitless currently although not tested or up to speed yet. BSR foams are the best although hard to get here so you'd most likely need to import from the US.

 

[Darren W]

Nice pass Darren.
What foams are you planning on running eventually then?

I've got SP Racing 50 shore foams on my Limitless currently although not tested or up to speed yet. BSR foams are the best although hard to get here so you'd most likely need to import from the US.

I have a few sets of the Contact foams, 35 shore which I’ll put on once it’s stability is addressed.
If needed I’ll get a few sets of either BSR’s or Gone Bananas shipped over.

 

[BashingBrian]

When are you gonna open the aerodrome up so we can all turn up and speed run our cars...???

 

[Darren W]

When are you gonna open the aerodrome up so we can all turn up and speed run our cars...???

If it was my call then tomorrow but they are strict at the best of times and even more so now with Covid around. The circuits have something running on them pretty much every day in some way or another so grabbing track time is tricky. Once things settle down I will speak with the powers that be and see what they say about the possibility of some runs.

 

[BashingBrian]

I'll keep my fingers crossed..?? I'd be happy to pay for track time..?

 

[Darren W]

After the flip at 111mph the car is on the bench and fully stripped whilst checking for damage. I still can’t believe all that I have found is a stripped Savox servo gear!
Nothing bent, nothing cracked and no bearings flat spotted. Tough little car!!!

 

[rotauq]

Looking at your current configuration, the velcro front left/right is to hold the batterypacks i assume. I see you stripped the servo/receiver box, but is that enough to fit a 5k+ Ah 4S battery and still use the original body cover?
Must be pretty thin batteries.

 

[Darren W]

Looking at your current configuration, the velcro front left/right is to hold the batterypacks i assume. I see you stripped the servo/receiver box, but is that enough to fit a 5k+ Ah 4S battery and still use the original body cover?
Must be pretty thin batteries.

I have just enough room for now to fit in a pair of 4s 5000mah packs with one on each side. I think with a push fit it could take 6000mah packs to be honest.
The car won't have this body on for very much longer though, it's only on whilst I do the first few runs to get some time on the car and find out what works and doesn't with regards to setup. The final body is a streamliner concept which I will vacuum form from 2.5/3mm material.

One good thing about the limitless body is not only is it strong as hell but it also holds the batteries and whatever else breaks loose during a shunt!

 

[rotauq]

I've been 3D printing my own LMP1 inspired bodyparts with the idea to keep using the original body (except for the nose-part):

But my big hardcase batteries just don't seem to fit. I've been running with them placed on one side and the XLX on top of the bracebar. These batteries gave me less ripple and voltage sag than my alternatives. Then again my esc was running quite hot and a cable desoldered itself from the esc, so maybe it was just that.

You are also not using heatsinks/fans on the motor. Are you such a patient guy, waiting it to cool down after a run? Weight reduction? What is your argument?

 

[Darren W]

I've been 3D printing my own LMP1 inspired bodyparts with the idea to keep using the original body (except for the nose-part):
View attachment 100263
But my big hardcase batteries just don't seem to fit. I've been running with them placed on one side and the XLX on top of the bracebar. These batteries gave me less ripple and voltage sag than my alternatives. Then again my esc was running quite hot and a cable desoldered itself from the esc, so maybe it was just that.

You are also not using heatsinks/fans on the motor. Are you such a patient guy, waiting it to cool down after a run? Weight reduction? What is your argument?

The printed parts look great.

I don't run fans as it's extra weight and battery usage. We spend however much on searching to find the decimal places of power and weight yet add fans that add to both.... Yes they don't draw much current but it all adds up.

I can run fairly close back to back runs as the kit starts off very cold and is only just over warm after the run. (esc 43c, motor 65c)

 

[rotauq]

Thx
I will give it a try without heatsinks/fans on the motor. Maybe lower the timing a little (running 15 atm) See what it does. Up to now i've been running all fans via an ubec, not having that extra amp running through the esc.

 

[Darren W]

Thx
I will give it a try without heatsinks/fans on the motor. Maybe lower the timing a little (running 15 atm) See what it does. Up to now i've been running all fans via an ubec, not having that extra amp running through the esc.

You really need to be on it with watching the temperatures. I have temperature strips on both the motor and esc to make sure that it’s staying within parameters.

 

[rotauq]

Yeah, i have the flysky sensors showing temps on my radio and always bring my infrared heatgun.

Out of the box I wonder what a bucket of liquid nitrogen would do. Pour some over the motor and esc before every run. From my days as a computer overclock fanatic i can confirm most electrical systems like cold/capacity for heat dispersion

 

[LibertyMKiii]

Yeah, i have the flysky sensors showing temps on my radio and always bring my infrared heatgun.

Out of the box I wonder what a bucket of liquid nitrogen would do. Pour some over the motor and esc before every run. From my days as a computer overclock fanatic i can confirm most electrical systems like cold/capacity for heat dispersion

A lot of guys take the cans of compressed air and turn them upside down to freeze the motor before a run. I wouldn't mind the wet condensation on the motor, but maybe risky on the XLX. MMX8s should be ok with that being more water proofed....

Also worth noting you want the LiPos at 95-120 F. Colder temps and they flow less amperage. Obviously starting temps any hotter and they could be too hot after the run.

 

[rotauq]

I wouldn't mind the wet condensation on the motor, but maybe risky on the XLX. MMX8s should be ok with that being more water proofed....

Plastic spray will save most electronics from condensation. It saved many of my mainboard in the past.

 

[jondilly1974]

A lot of guys take the cans of compressed air and turn them upside down to freeze the motor before a run. I wouldn't mind the wet condensation on the motor, but maybe risky on the XLX. MMX8s should be ok with that being more water proofed....

Also worth noting you want the LiPos at 95-120 F. Colder temps and they flow less amperage. Obviously starting temps any hotter and they could be too hot after the run.

We just need to put some dry ice on the heatsink ... no water involved ???

 

[rotauq]

We just need to put some dry ice on the heatsink ... no water involved ???

The water is in the air unfortunately. Anything radiating cold below ambient temperature is prone to get condensation. Ever looked closely at an airco?

 

[Darren W]

I ran the car again today, this time with the rear wing cut flat, essentially all it has are vertical stabilisers. I also changed the steering servo to a higher torque Savox as the previous unit was really out of it's depth on this car.

The first careful pass was very straight and as stable as it was at 85mph which made me confident enough to do another pass and give more throttle input. This run was a 125mph and couldn't have been better, apart from more speed..

The next run was the run where I expected the 140 goal to be reached but as the car went past me I heard the start of a blowout so got out of the throttle which was annoying as the car felt great and was starting to get a move on.

A chunked front Hoon was the cause of the noise and as annoying as that is, it proved I made the correct decision to get out of the throttle and stop the run rather than push on hoping to hit bigger numbers.

Sorry about the wind noise in the video, it really wasn't this windy. I'll find a better camera with an external microphone for my videos from now on.

 

[jondilly1974]

I ran the car again today, this time with the rear wing cut flat, essentially all it has are vertical stabilisers. I also changed the steering servo to a higher torque Savox as the previous unit was really out of it's depth on this car.

The first careful pass was very straight and as stable as it was at 85mph which made me confident enough to do another pass and give more throttle input. This run was a 125mph and couldn't have been better, apart from more speed..

The next run was the run where I expected the 140 goal to be reached but as the car went past me I heard the start of a blowout so got out of the throttle which was annoying as the car felt great and was starting to get a move on.

A chunked front Hoon was the cause of the noise and as annoying as that is, it proved I made the correct decision to get out of the throttle and stop the run rather than push on hoping to hit bigger numbers.

View attachment 100482


Sorry about the wind noise in the video, it really wasn't this windy. I'll find a better camera with an external microphone for my videos from now on.

Depending on your camera, you might be able to find a foam surround to minimize wind noise.

 

[Darren W]

Depending on your camera, you might be able to find a foam surround to minimize wind noise.

I have tried a GoPro hero 4 and a RunCam 5 and both have had the same results. I have thought about putting some foam on the mic hole as you suggest but never got around to it so may give it a try and see if it helps. The issue I have found with both of these cameras that makes them hard to used is framing, as well as wind noise. When it’s on my head it’s a guess as to what is and isn’t in shot and I’ve filmed so much content but can’t use any of it. I may use my iPhone with the head mount and an external mic on my shirt and see if that improves both visual and audio quality.