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Tamiya mini cooper

Old 11-23-2008, 10:55 PM
  #7741  
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Can't really see it in the first pic where you put the CA so I draw the red ring.

I smooth it out with my finger after running a bead around but you could use gloves if you wish.


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Old 11-24-2008, 12:13 AM
  #7742  
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my advice also:
go for 1400 grams weight or even more, and just add some CA-glue on the front-tyres, as described earlier.
I had a competition, two weekends ago and we were all running on normal rubber tyres (slicks, M-grips, Super-grips ...) but there was one guy that drove foamtyres. It were regular 1/10 foam-tyres for a nitrocar which he trimmed down to thes size of a mini-tyre. These tyres were very wide and flat and gave him much traction and no traction roll in corners and he doubled us all the time.
So I start pushing, trimmed the car down to 3mm on the lowest part (and don't bother messing with shock-oil, shock-springs ... as you can read on MINI.NET this doesn't affect the handling of the car much. Driving skills and tyres are much more affecting!)
.. and I used some CA on the tyres. Well, .. I still lost but he wasn't doubling us all the time anymore. In stead of -5 laps, me and my friend only had -1 lap on the last final
That's improvement for ya

I know some guys who even put some more ca on the tyre, in high grip conditions, so not only on the side of the tyre but even on the outer border of the tyre-surface. Works great.

Also, we found out, that the front tyres (we use M-grips and standard mini-tyre overhere mostley) were improving as they weared down. So we only CA them once, or maybe a second time after some races but that's it.
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Old 11-24-2008, 12:16 AM
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Originally Posted by Low_E
... trimmed the car down to 3mm on the lowest part
This is the ground clearance correct?
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Old 11-24-2008, 12:52 AM
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yup, 3mm ground clearance, but that's on a very flat carpet!
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Old 11-24-2008, 12:57 AM
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Yeah, I thought so. 3mm will result in lot of negative camber wouldn't it?
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Old 11-24-2008, 02:44 AM
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I know that this is a bit off target at the moment but the TITC event that is held in Thailand every year is having a Mini class in Feb 2009.

Originally the class was to be a combined 2WD and 4WD class but the organisers have seen the light and are separating the classes.

This event wil be based on the following basics:

Black Sports Tuned motor
Nimh batteries
Controlled Ride tyres

This event is an awesome event in a fantastic country. Keep your eyes open for more information
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Old 11-24-2008, 04:38 AM
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Originally Posted by Ashley Cobb
Can't really see it in the first pic where you put the CA so I draw the red ring.

I smooth it out with my finger after running a bead around but you could use gloves if you wish.
Ash...what effect does the CA glue have??? HAd serious traction roll issues running Team Powers 36/32 on friday nite on an indoor track....switched to some HPIs and it solved my issues.
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Old 11-24-2008, 08:16 AM
  #7748  
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Originally Posted by stocker
Yeah, I thought so. 3mm will result in lot of negative camber wouldn't it?


yup, indeed, camber will be affected, but getting more neg camber, grip is improved. I lowered the ground clearance do have a lower center of gravity.
Downside on this is that the Rolling centre is affected also, so You might consider keeping it on 5mm, as I use to drive normally.


The CA-glue on the tyres lowers lateral grip. When driving into the corner, normally you also release the throthle, So weight is transfered to the front and the car dives a bit, and the front tyres get even more grip. When this effect is too great, the car simply tumbles over the outher wheel ...
With the CA-glue on the side of the tyre, the tyres don't bite into the carpet and can slide a bit when the weight and lateral force becomes to high, so the car won't tumble (we call it "griproll" overhere), but will slide a bit.
And as the CA is only aplied to the side of the tyre, the normal grip for accelerating or decelerating is not affected
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Old 11-24-2008, 09:17 PM
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Default BEC for receiver

Hi

Had the same issue with the Tamiya ESC and a JR (ex) flying receiver so fitted two tiny 1 amp diodes in series in the power feed from the ESC to the receiver. Each diode drops 0.6 volts so down from 7.2 volts nominal to 6 volts and never a moments problem over three years. Ultra compact and saves on a clunky receiver pack.

Cheers
Dave

[QUOTE=Mabuchi540;5079765]

Ok so I've just got a Suzuki Swift only to find out that the included esc (and the one you have to use in the New Zealand mini class) does not have a bec. This would not usually be a problem but it turns out that the receiver in my new radio (MX3-G dss 2.4 ghz) doesn't have one either.

QUOTE]
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Old 11-24-2008, 09:22 PM
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I think your electrical theory is a little off there... if you were using a diode it would only allow current to flow in one direction. Maybe you used a transistor (regulator) or a resistor. Resistors are a pretty rough way of doing it though.

In one of my planes I used a 5v regulator with a capacitor to cut down on glitching. Can't remember exactly how I wired it but I will find out and post up.

Originally Posted by Mabuchi540


Ok so I've just got a Suzuki Swift only to find out that the included esc (and the one you have to use in the New Zealand mini class) does not have a bec. This would not usually be a problem but it turns out that the receiver in my new radio (MX3-G dss 2.4 ghz) doesn't have one either.

QUOTE]

Last edited by Ashley Cobb; 11-24-2008 at 10:01 PM.
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Old 11-24-2008, 09:30 PM
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Just checked,

use a 5v 1A regulator (LM7805) with a small capacitor across the input will prevent glitching with my setup.

This works well in my plane, the ESC is opto which has no BEC.

The tamiya speedy does have a BEC though.

"External Capacitors An input bypass capacitor is recommended in case the regulator is more than 6 inches away from the usual large filter capacitor. A 0.1F disc or 1F solid tantalum on the input is suitable input bypassing for almost all applications."
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Old 11-24-2008, 09:58 PM
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Originally Posted by Ashley Cobb
I think your electrical theory is a little off there... if you were using a diode it would only allow current to flow in one direction. Maybe you used a transistor (regulator) or a resistor. Resistors are a pretty rough way of doing it though.

In one of my planes I used a 5v regulator with a resistor and capacitor to cut down on glitching. Can't remember exactly how I wired it but I will find out and post up.
Erm, why would you want current to flow in the other direction?
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Old 11-24-2008, 09:59 PM
  #7753  
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Originally Posted by stocker
Erm, why would you want current to flow in the other direction?
You used the word "diode" incorrectly. A diode won't reduce voltage as you have stated. A diode stops current from flowing in one direction.

"The function of a diode is to allow current in one direction and to block current in the opposite direction"
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Old 11-24-2008, 10:19 PM
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Originally Posted by Ashley Cobb
You used the word "diode" incorrectly. A diode won't reduce voltage as you have stated. A diode stops current from flowing in one direction.

"The function of a diode is to allow current in one direction and to block current in the opposite direction"
You're right, that's the purpose of a diode. But the original poster (not me) is right too. A diode also reduces voltage by 0.6 to 0.7v through its P-N junction, a very useful feature used to set a potential difference to bias a transistor for example.
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Old 11-24-2008, 10:38 PM
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Originally Posted by stocker
You're right, that's the purpose of a diode. But the original poster (not me) is right too. A diode also reduces voltage by 0.6 to 0.7v through its P-N junction, a very useful feature used to set a potential difference to bias a transistor for example.
Yeah I guess but there are better ways to do it.

Anyway the tamiya speedy does have a BEC anyway
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