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Q- Do your flat head screws sit flush? In some of the pics it looks as though they may not be. It could be an optical illusion - or, I thought maybe those screws have a small radius on the inside corner that may be riding on your holes and slots (as in the motor mount).

Quote:

Originally Posted by pinkpanda3310 (Post 328891)

That's very impressive to look at :yes:

I am a little curious though, why have you chosen to run 5s? With all the weight saving you've done it would still be a rippin' truck and you could use the internal bec on the quark.

Thanks man... I often just sit and stare at it too in amazement :lol:.... hmm... I choose 5s because I knew that's what the quark could really handle realistically...
Also, I saw a vid on youtube of a 10xl running 5s (can't find it again though) and it was moving quite nicely around the track... I have seen other 5s setups with similar KVs
getting really good results. I'm not sure what kind of performance I would get from 4s.... Maybe I'll try a 12 cell pack to see how it rolls and give you some feedback.

From the speed calculator:

5s with 14 pinion

Differential Ratio: 4.3
Transmission Ratio: 1
Other Ratio: 1
Spur Tooth Count: 52
Pinion Tooth Count: 14
Total Voltage: 18.5
Motor KV: 1624
Tire Diameter (inches): 5.65
Tire Ballooning (inches): 0
Motor Current Draw: 0
Motor Coil Resistance: 0
Spur/Pinion Ratio: 3.71 : 1
Total Ratio: 15.97143 : 1
Tire Circumference (inches): 17.75 inches (450.85 mm)
Rollout: 1.11:1
Total Motor Speed: 30044 RPM
Vehicle Speed: 31.62 mph (50.79 km/h)
Effective KV Value: 1624
KT constant: 0.83 oz-in/A

5s with 16 pinion

Differential Ratio: 4.3
Transmission Ratio: 1
Other Ratio: 1
Spur Tooth Count: 52
Pinion Tooth Count: 16
Total Voltage: 18.5
Motor KV: 1624
Tire Diameter (inches): 5.65
Tire Ballooning (inches): 0
Motor Current Draw: 0
Motor Coil Resistance: 0
Spur/Pinion Ratio: 3.25 : 1
Total Ratio: 13.975 : 1
Tire Circumference (inches): 17.75 inches (450.85 mm)
Rollout: 1.27:1
Total Motor Speed: 30044 RPM
Vehicle Speed: 36.14 mph (58.05 km/h)
Effective KV Value: 1624
KT constant: 0.83 oz-in/A

4s with 14 pinion

Differential Ratio: 4.3
Transmission Ratio: 1
Other Ratio: 1
Spur Tooth Count: 52
Pinion Tooth Count: 16
Total Voltage: 14.8
Motor KV: 1624
Tire Diameter (inches): 5.65
Tire Ballooning (inches): 0
Motor Current Draw: 0
Motor Coil Resistance: 0
Spur/Pinion Ratio: 3.25 : 1
Total Ratio: 13.975 : 1
Tire Circumference (inches): 17.75 inches (450.85 mm)
Rollout: 1.27:1
Total Motor Speed: 24035.2 RPM
Vehicle Speed: 28.91 mph (46.44 km/h) :whip:(not very impressive)
Effective KV Value: 1624
KT constant: 0.83 oz-in/A

Quote:

Originally Posted by JThiessen (Post 328898)

Q- Do your flat head screws sit flush? In some of the pics it looks as though they may not be. It could be an optical illusion - or, I thought maybe those screws have a small
radius on the inside corner that may be riding on your holes and slots (as in the motor mount).

Yes they do... the little corner are sitting in the holes and the heads are flush with the surface of the carbon (the holes are just over 3mm).

Quote:

Originally Posted by ANGRY-ALIEN (Post 327293)

Thanks man... This is really the part of the hobby I love too... I wanted to keep the heads of the screws on top because it adds a little something to the look of the chassis.

Yep... that's correct I did a test counter sink with a spare piece of carbon and it didn't work out so well.

Thanks, I didn't know that about CF.

Beautiful work man. Side note- whenever I countersink CF it works fine, is it possible that your countersink bit is dull?

Quote:

Originally Posted by BL_RV0 (Post 329442)

Beautiful work man. Side note- whenever I countersink CF it works fine, is it possible that your countersink bit is dull?

Thanks man... regarding countersinks... I believe the problem I had was that the wrong tools were used to make the countersinks...
A drill bit just doesn't 'cut' it... and I didn't have access to a countersink tool at the time. Recently though, I did find that an abrasive
Dremel tool worked very well... It didn't cut into the carbon, but in stead, it grinds the material away smoothly and reduces the chances of delamination.

You need to make the $7 investment into a countersink bit then :lol:

http://www.dynenco.net/countersink_f...ountersink.jpg

yeah... I guess so:lol:, but I really prefer to stick with the abrasive tool for now.

It continues... I built a little bracket for the heatsink to be bolted to that would fit on the upper plate that didn't appear too intrusive on the design...

... have a look see...

http://lh6.ggpht.com/_4vPm5E8J5HA/Su...2/DSC_0194.jpg

http://lh6.ggpht.com/_4vPm5E8J5HA/Su...2/DSC_0197.jpg

http://lh4.ggpht.com/_4vPm5E8J5HA/Su...2/DSC_0198.jpg

http://lh5.ggpht.com/_4vPm5E8J5HA/Su...2/DSC_0201.jpg

http://lh4.ggpht.com/_4vPm5E8J5HA/Su...2/DSC_0203.jpg

http://lh3.ggpht.com/_4vPm5E8J5HA/Su...2/DSC_0207.jpg

http://lh6.ggpht.com/_4vPm5E8J5HA/Su...2/DSC_0209.jpg

I took the truck to my office parking lot yesterday to put it through passes... I loved the way it performed... it was well balanced and stable despite the surface being wet from a down poor.
I did most of the testing with 16 cells and 14/52 setup... The center diff worked well in keeping the front end on the ground... It just pulled hard through out the rpms until the 14 pinion gave in...
The motor mount screws were loose, so the meshing got messed up. I changed it out for a 16 and tested it on 5s... All I can say is... :surprised:WOW!!! The hacker came alive...
Keeping the front wheels on the ground was no longer easy (BTW I am using 50K in the center diff). Needless to say, the front tyres are ballooning like crazy now...

Despite all the fun, I'm still a little concerned about the temps... the motor went to the high 160s and esc was floating around 135/140... I might be going back to the 14 pinion
(need to order new ones) to lower the temps on the esc and add a little fan on the motor to try and keep it cooler.

More to come... I hope.

Maybe some thermal grease between the esc and heatsink?

If 14t is good, but 16t awesome, maybe try a 15t- split the difference as it were? Sounds like its working awesomely either way :yes:

Hey Neil, I'll get some thermal grease this weekend to see what kind of a difference it will make. Yep:yes:, the 15 pinion will be a good choice too... I'll send Mike my order later today.

great project ! i love

Thanks man... Trying to get some work done on it this week... new body, center diff repairs and esc mods. I am hoping to get some action shots this weekend before I break it again :lol:

Too much power huh? :whistle:

:lol: Not yet!!! but I'm getting there.