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Old 02-28-2013, 06:38 PM   #196
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Thanks for posting the charts and marking them. Makes it easier to read.
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Old 03-04-2013, 06:37 PM   #197
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Just uploaded 3 new models. Two from users, TOP Photon EX and a blast from the past the Xray T1 EVO2. Keep those models coming.

The AE RC8T econv truggy is back together and there as well.
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Old 03-08-2013, 06:33 AM   #198
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Bob, enjoyed the video and still trying to understand using RC crew chief for setup ideas. Can you elaborate a little more about reading your tires for buildup and relating it to your camber settings. You can use private messaging (or even better your crew chief thread) if you would rather not muck up this thread.

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If you see a build up of rubber on the outside edge of your tires what is to blame is either too much static camber or too much camber gain IMO.

This is my explaination:

As the chassis rolls the camber angle on the outside tire decreases due to the chassis roll angle. Similarly the camber angle on the inside tire increases such that there can be a gap (or very low contact pressure) at the outside edge of the tire. The gap is also strongly dependent on the tire sidewall stiffness, air gap and hardness of insert all three of which affect how much the tire carcass deforms under lateral load.

So if we assume on the inside tire there is a gap at the outside edge then rubber that is stripped off will move from the inside to the outside of the tire due to the slip angle of the tire. Once the rubber reaches the gap it will start to build up.

If the next turn is in the opposite direction then our inside tire with the buld up now becomes the outside tire. If our camber settings are correct and the tire makes contact over it's full width any build up will be removed and all is good. If not then turn by turn the buildup will continue to increase.

So build up on the outside edge of your tires is an indication the tire is not making full contact with the racing surface and consequently not achieveing maximum grip. That's my theory.
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Old 03-08-2013, 09:00 AM   #199
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Bob, thank you for taking the time to write that clear and descriptive explanation of using outside rubber buildup on your tires as a gauge for reading the effectiveness of your camber settings.

I understand and agree with your theory after reading that post. When I watched the video I thought you were only talking about the outside wheel and how it contacts the track. Thus I did not understand how a tire with too much camber would develop a buildup of rubber on the outside edge when it is not even touching the track during cornering.

Now that I realize you were taking about when a particular tire is on both the outside and inside of a corner how each can affect the amount of rubber buildup on that same tire.
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Old 03-08-2013, 02:22 PM   #200
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Correct me if I'm wrong, build up of rubber on the outside of the tire means that thru the corner the whole tire isn't touching the surface and that would mean decrease camber and the front tires will have full contact with the surface thus more front traction and steering?
I've only witnessed a build up on the outside of the front tires, so I am assuming you are talking about the front
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Old 03-08-2013, 07:42 PM   #201
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Build up can occur on the front or rear tires. To fix it reduce static camber, and or camber gain or soften the suspension so the chassis rolls more.
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Old 03-09-2013, 10:14 AM   #202
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Quote:
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So build up on the outside edge of your tires is an indication the tire is not making full contact with the racing surface and consequently not achieveing maximum grip. That's my theory.
I completely agree. Although I'm still fairly new to racing, this seems common sense to me. What I've found shocking is this simple visual analysis seems to be overlooked by many with plenty more experience than I. That's just an observation I've made as I questioned local talent for tips over my first couple years. All I can say is that every single time I've had buildup issues and reduced camber, the car became easier to drive and more responsive to further tuning... because the tire is simply working more effectively.
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Old 03-09-2013, 11:32 AM   #203
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Any chance of a 25.5 novak motor model? Only info I can find is the following:

Watts: 82
Maximum RPM: 50,000
kV: 1550 RPM/volt (unloaded)
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Old 03-09-2013, 05:11 PM   #204
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Any chance of a 25.5 novak motor model? Only info I can find is the following:

Watts: 82
Maximum RPM: 50,000
kV: 1550 RPM/volt (unloaded)
Sure will. I'm away this weekend but will upload a model beginning of the week.
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Old 03-09-2013, 05:16 PM   #205
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Sure will. I'm away this weekend but will upload a model beginning of the week.
Much appreciated. Are you generating this data or so you have a source for it?

Dave
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Old 03-10-2013, 05:57 PM   #206
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The electric motor model uses DC Permanent Magnet equations. Knowing the Kv, max power and voltage you can come up with a fairly accurate model.

I plan to build a flywheel dyno in the near future which will allow better models to be developed and motors to be compared head to head.
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Old 03-11-2013, 12:29 PM   #207
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Hey Bob, any chance a droop setting could be added to the handling tab to see the direct correlation of droop limitation to wheel loads? I understand that droop only affects wheel loads during chassis movement so perhaps an option to show the wheel loads at the currently selected g load in handling would work?
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Old 03-11-2013, 02:03 PM   #208
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Anyone else having issues w/ CG calculations? I originally calculated CG at 2" and I was at 20mm but after reading the documents it mentions testing is most accurate at 4-5" I'm around 47mm this way. I've ensured that there is nothing contacting my scales aside from the tires. Looking at the stock tc5 file it shows 30mm as the CG so I find it hard to believe 47mm is accurate. Any opinions? I'm also measuring w/ the body on.

Dave
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Old 03-11-2013, 02:49 PM   #209
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Quote:
Originally Posted by TT_Vert View Post
Hey Bob, any chance a droop setting could be added to the handling tab to see the direct correlation of droop limitation to wheel loads? I understand that droop only affects wheel loads during chassis movement so perhaps an option to show the wheel loads at the currently selected g load in handling would work?
It is difficult to add droop the static wheel load calculations as the point where the droop limit is reached is a function of suspension geometry, g load and roll angle. What's I need to do is link between the dynamic and handling page. Something else for the wish list.
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Old 03-11-2013, 03:44 PM   #210
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Originally Posted by TT_Vert View Post
Anyone else having issues w/ CG calculations? I originally calculated CG at 2" and I was at 20mm but after reading the documents it mentions testing is most accurate at 4-5" I'm around 47mm this way. I've ensured that there is nothing contacting my scales aside from the tires. Looking at the stock tc5 file it shows 30mm as the CG so I find it hard to believe 47mm is accurate. Any opinions? I'm also measuring w/ the body on.

Dave
47mm is definitely way off. All the TC's I have measured have been between 29 and 31mm body on. Some things to check.

1. Wheel weights were entered for the car oriented as shown on the graphic.

2. When you raise the rear make sure you account for the thickness of the scales. I always place scales under the rear as well so I don't need to account for this.

3. RL is tire radius not diameter. I always use 31mm for 63mm tires. The .5mm accounts for some deflection of the tire.
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