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Old 05-26-2008, 02:23 PM   #61
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Wedge, Corner Weights
Wedge was originally applied to full size oval race cars by driving a wedge between the right rear leaf spring and the axle housing. This adds preload to the right rear. This means the right rear carries more weight as we have compressed that spring a little bit. At the same time the car tends to rock accross a diagonal line and loads up the left front wheel. Wedge increases front cornering traction at the expense of rear cornering traction. This was very helpfull on big front engine sedans that tend to push from the large amount of weight in the front.

Wedge works by preloading the left front tire (much the same as when we move weight left) This unloads the overloaded right front on the heavy sedan. As a result when weight transfers in the corner we approach that desired 50-50 weight split on the front axle that creates maximum cornering.

Now a pan car is not like a front engine sedan. It is heavy in the back to give us better forward traction. For this reason it has a natural tendency to oversteer in the corner. On the pan car oval then what we do is preload the left rear or give the car some left rear down tweak. This loads up the right front as well. You cant see this on the front scale reading because we have also put the battery on the left side. This loads up the left front enough to obscure the increase that happened at the right front. This kills some steering traction and it keeps the battery off the ground. Now that is the way I see it. We are really adding reverse wedge or negative wedge or more simply left downtweak.

The scales come in handy if you want to share setup information on your oval car with another guy. There is not another real way to say accurately how much preload you have put on the left rear without measuring it on a scale. Do you need scales to run oval. Definitely not. You are going to use this left downtweak often to fine tune the oversteer balance. You can only determine this by driving the car on the track. If you want to share your setup or be more scientific about your setup then a set of those four corner weight scales will give you a quick measure of left down tweak.

My loaner battle axe is at 11.5 ounces heavier on the left rear. From setups posted above I could increase this. To increase it substantially I will have to install that stiffer right rear spring. I have the collar already about to the end of the threads on the shock body.

To use the scales tare them all to 0 put on the car. Bounce it on the suspension. Expect some error maybe .2-.3 ounces as shock stiction will cause some friction.

Note that you need a flat surface. I am using two scales and a beam of the same height. This works as good as four scales.

That third pic shows the car with a gold spring preloaded quite heavy on the right rear. The left rear is up to 1 lb 0 ounces now for a preload of about 13.5. The right rear shock end has now failed. I'll have to screw it on a little farther.

I had to replace both shock ends to use a copper spring. I cut the ends real straight to match the length, used Losi rod ends, tapped them to reduce force putting them on and drove them on untill the end touches the caps. That aluminum threaded stud on both ends of the shock is a weak point in this type of car. The Losi XXXT rod ends will strengthen things some.

other opinions are welcome.

John
Attached Thumbnails
CRC Battle Axe, GenXPro 10, 1/10th pan, Brushless, Lipo,4c, Road, Oval,TipsandTricks-corner-weights-rear-resized.jpg   CRC Battle Axe, GenXPro 10, 1/10th pan, Brushless, Lipo,4c, Road, Oval,TipsandTricks-corner-weights-front-cropped.jpg   CRC Battle Axe, GenXPro 10, 1/10th pan, Brushless, Lipo,4c, Road, Oval,TipsandTricks-corner-weights-gold-spring-resized.jpg  

Last edited by John Stranahan; 08-21-2008 at 08:13 PM.
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Old 05-26-2008, 06:38 PM   #62
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Some thoughts on adjusting tweak . . .

First off, when I initially install shocks on a pan car, I strive to have the length of them so that they are even between right and left sides, and also at a size that makes the shock compressed about halfway thru its travel.

Once I have achieved that, I take the pod and twist it all the way to the right, and adjust the left shock so that the spring has no play, nor any excessive compression. Basically I'll hold the spring and twist the collar until the spring will not turn easily. The process is then repeated in reverse for the right spring while twisting the pod to the left.

When adding weight to the left side, I'll tighten the right spring and loosen the left in equal proportions. The process would be in reverse if you wanted to remove weight. It doesn't have to be an exact science, but should be generally adhered to if at all possible. This method will prevent putting an extreme amount of pre-load on just one side.

It's kind of the same thing as one would do using t-plate tweak screws.
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Old 05-27-2008, 10:52 AM   #63
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Default Chassis tuning info

Below are a bunch of good tips and info I found, taken directly from the Customworks Aggressor Manual. Note that some examples are specific to the Customworks car and may not apply to all pan cars as they may not have the same adjusting capabilities. However the theories should still apply. Enjoy!

TUNING TIPS: These are some general guidelines for optimizing handling
performance. None of these “tips” are EVER set in stone. On any given day this manual or any chassis engineering book or guru can be proved wrong by the almighty stop watch. A good way to approach chassis set-up is to try one change, practice it, think how the car felt different from before, and compare lap times from the stop watch…..this will never fail.

Car is Loose or Oversteers
Install Wing to Rear of Car
Slide Wing Toward Rear of Car
Increase Wing Angle
Add Wedge/Tweak to Chassis Using Side Shocks
Softer Side Shock Springs
Stiffer Front Springs
Softer Center Shock Spring
Decrease Center Shock Spring Tension
Try Harder Front Compound Tire
Try Softer Rear Compound Tire
Move Battery to Center of Car
Raise Front Ride Height
Lower Rear Ride Height
Move RF Suspension Out
Move RR Tire Closer to Pod
Increase Castor

Car Pushes or Understeers
Slide Wing Toward Front of Car
Decrease Wing Angle
Remove Wedge/Tweak to Chassis Using
Side Shocks
Stiffer Side Shock Springs
Softer Front Springs
Stiffer Center Shock Spring
Decrease Center Shock Spring Tension
Try Softer Front Compound Tire
Try Harder Rear Compound Tire
Move Battery Toward Left Side
Lower Front Ride Height
Raise Rear Ride Height
Move RF Suspension IN
Move RR Tire Away From Pod
Decrease Castor

Car is Erratic:
Bent Front Suspension Pin: Remove spring and check for free movement
Chunked Tire: Check side wall to see if rubber is still glued to wheel.
Bent Axle: Tire “wobbles” while spinning.
Loose Screws: Especially Chassis Screws, add Blue Loctite to prevent.
Bound Ball Joint: Steering link and shocks should spin free on balls.
Shocks: Either Bound Up, Bent Shaft, or Out of Oil.
Bearings: Broken or completely seized.
Foreign Objects: Unlucky Dirt/Stones preventing suspension movement especially in front pivot balls.
Bottoming Out: Look on bottom side of chassis for buffed or scratched areas.
Tire Rub: Look on inside of body for extreme black marks from tires.
Blown Differential
Radio Problem: Bad Servo, Weak Servo Saver Spring, Transmitter Pot blown.

Castor: Angle of the kingpin in relation to a vertical plane as viewed from the side of the car. Increasing the angle will make the car more stable out of the turn as well as down the straights and increase steering entering a turn.
Decreasing the angle will make the car feel more “touchy” at high speeds and help steering while exiting the turn.

Front Toe IN: Front edge of car tires point toward the chassis as viewed from above the car. Settles and makes steering reaction less aggressive especially on acceleration. Easier set-up to drive and works well on bumpy tracks.

Front Toe OUT: Front edge of car tires point away from the chassis as viewed from above the car. Increases aggressiveness of car especially on entry to the turn. Works well on smooth, high bite tracks where rear traction is not a problem. Generally the preferred set-up for pan car racing.

Camber: Angle by which the tire and wheel contacts the racing surface when viewed from the Front or Rear of the car. Oval cars generally always have the Right Side tires leaning TOWARD the chassis and the Left Side tires leaning AWAY from the chassis. In oval racing jargon, more camber means more angle TOWARD the chassis on the Right Side and more angle AWAY from the chassis on the Left Side. Starting from 0 Degrees (tire standing
straight up) ADDING camber in the oval fashion will increase traction when cornering however remember too much of anything is generally a bad thing. Camber is usually adjusted (especially foam tires) when one edge of the tire is wearing more than the other.

Camber Gain: Angle of the Upper Suspension Arm relative to the ground, so that when the suspension travels the amount of camber for that tire will increase. With the arm parallel to the ground the front suspension will have the least amount of camber gain. Lowering the Upper Suspension Arm on the Upper Suspension Mount will increase the amount of camber gained when the suspension travels. There is not a “correct” set-up and once again
too much of anything is generally bad. This will help change the “feel” of the car thru the turns.

Shock Angle (Center Shock): Mounting the shock in the lower positions will increase the stiffness of the spring and generally works best on smooth high bite tracks. Mounting the center shock in the upper positions (shock parallel to the ground) will make the spring feel softer and works best on low grip surfaces and bumpy tracks as well.

Shock Angle (Side Shocks): Mounted in the shocks in the lower positions will increase the stiffness of the spring and will decrease chassis roll which is good for high bite tracks and especially flat tracks. Side Shocks mounted in the upper holes (shocks parallel to the ground) will make the springs feel softer and will increase chassis roll which seems to be best for cap tire racing and low bite flat tracks.

Tweak: Refers to the amount of weight placed on the Left Rear and Right Front tires by adjusting the collars on the side shocks. Threading the collars IN on the right side shock and OUT on the left side shock will place more weight on the Left Rear tire and on the Right Front tire and will make the car push. Threading the collars OUT on the right side shock and IN on the left side shock will place more weight on the Right Rear tire and Left Front tire and will make the car loose. Generally the car is always set-up so that it is “tweaked” so that the Left Rear is heavier than the Right Rear. You can check to see how much weight is on each rear tire by using a hobby knife to pick up the rear of the car under the center of the rear pod. The Right Rear should come off the ground about 1/8" inch before the Left Rear does. The higher the Right Rear comes off the ground before the Left Rear does, the more tweak and more weight that is on the Left Rear.

Ride Height: Check by pushing the chassis down once or twice to simulate bumps on the track. Having the front end higher than the front will make the car increase rear traction especially out of the turn. Having the front end lower than the rear end will make the car increase front traction especially entering the turn. Generally a safe place to start is with all corners of the car even with 1/4" ride height under the chassis. Since these cars sit so close to the ground even 1/16" difference is drastic.

Battery Placement: Since the battery is the single heaviest component in the car its placement is critical. Moving the battery further to the left will make the car turn more thru the center of the turn and coming off but will decrease forward bite. Placing the battery closer to the center of the car will work better on low bite tracks and increase forward bite.

Wheelbase: Wheelbase is the distance between the front and rear axles. Mounting the entire front end assembly in the forward position (10 3/8") will make the car more stable on long fast tracks with flowing turns or tracks with low bite compared to the power used.
Running the entire front assembly in the rear most position (9 5/8") will make the car more suitable for short tracks where you are constantly turning. Using the middle position (10") is a happy-medium of both set-ups described.

Long Pod: Unique to this car is the option to increase the length of the rear pod and keep the wheelbase and body mount positions the same. Increasing the pod length (distance from axle to t-bar) makes the center shock and t-plate effectively a lot softer and best for severely bumpy conditions and flat tracks.

Front Track Width: This can be viewed as the distance between the two front tires but more accurately it is the distance from the center of the car to the individual tire. For example moving the Right Front tire closer to the center of the car will increase the amount of weight transferred to the tire when cornering, best used when the car is extremely tight. Moving the Right Front away from the center of the car will decrease the amount of weight transferred to the tire when cornering, best used when the car is
extremely loose or over aggressive to drive. Since the majority of the cars cornering ability is done thru the Right Front tire, moving the location of the Left Front tire will not be near as drastic but will help fine tune your set-up.

Rear Track Width: Distance from the rear pod the tires are mounted. This is accomplished using spacers on the axle located between the bearing and the hubs. Moving the Right Rear away from the pod will increase steering in the center of the turn and exiting while decreasing forward bite off the turn. Moving the Right Rear closer to the pod will increase forward bite thru the center of the turn and especially while exiting. The opposite can be said for the location of the left rear. Mounting the left rear close to the pod will increase steering thru the center of the turn and decrease forward bite off the turn, while mounting it further from the pod will increase stability and forward bite while cornering.

Rear Pod (On-Center or Offset): Mounting the pod “on-center” positions the motor (which is the majority of the weight of the rear pod) pretty much center in the rear pod and generally works best in wide open type driving classes like stock. Mounting the pod “offset” places the motor closer to the left rear tire and helps keep the left rear tire planted during acceleration and works well in modified classes.

T-Plate (On-Center or Offset): Unique to this car is the option to run the t-bar offset from the center-line of the car. Along with offsetting the t-bar the rear shock tower and shocks also offset creating even more left side weight on the chassis. This feature works well for flat tracks and especially modified classes when getting the power to the ground is critical.

Rear Steer: This feature allows you to run the axle straight in the car or angled ½ degree so that the rear helps turn the car in the same fashion as four wheel steering. This option works best on tracks where you are constantly turning and when forward bite off the turn is not a problem.

Rear Wing: To increase traction to the rear of the car wings can be mounted to the rear window of the body for foam tire racing or directly to the rear pod for cap tire racing. Generally every class of pan car racing uses a rear wing, with the exception of stock classes on very high bite tracks since the wing is extra weight and aero drag. On banked tracks the wing is mounted very flat and below the roof of the car so that just the side dams of the wing keep the car stable at high speeds. On flat tracks the wing is mounted at least even with the roof height of the car and angled up almost as much as the angle of the front window of the body.
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Old 05-27-2008, 01:31 PM   #64
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Barry-Thanks for the additional detail on setting tweak. Note to all that Barry has years more oval experience than I do. Thanks for the general setup guide. I'll look back over it in a bit.

Track Report
Track 93F air temp, track dusty but not as bad as before, traction medium

Oh my Gawd the car was perfect! Anyone could have driven it. Here are the changes I made. Note that I don't follow the one change at a time reasoning after I get some experience with the settings. There is not enough time in a life to do this. I use more of a shotgun approach and make several small changes to move the car in the right direction.

Left Down Tweak- 16 oz
This adjustment does two things. It loads the left rear and makes the car tighter (less oversteer). I also can't discount some possible benefit of having decent loading on the diagonal wheel the right front. This might be important on corner exit. Anyway the corner exit hooking was gone completely. The picture shows the adjustment I used with the copper springs. It also shows the Losi ball cups beefing up the shock ends which are at their limit of strength with these heavy springs. One note from Barrys post is that If I needed this right rear shock longer, i would not do it by screwing the ball cup out. This will cause bending of that aluminum stud. Instead cut a longer Losi truck ballcup and screw it all the way down after tapping it. A stiffer set of side shock springs may be in order for this car. Here is a link posted by Mike OBrien.


Wheel offset
Imagine your center of mass of the car with the two back wheels offset to the side both pushing forward equally. This is the desired effect on road. Both have equal torque (twisting clockwise or counter clockwise on the vertical axis) on the center of mass. Now let's say we put a 1/8 inch spacer inside the left rear tire. This side has more torque now. The lever is longer. There is now torque steer. There is a tendency to twist the car clockwise and aim it out to the boards.

I added 1/8 behind the left rear. The car was perfect. I took it out. It was OK but after a few laps I had a corner exit oversteer (still some dust on the track). I put it back the car was good again.

Front Springs
Generally stiffer front springs reduce your steering traction and cause more push (understeer). I found out the first time I ran a wide pan car on the big high speed sweeper that you can go too soft and reduce steering if the spring is going into coil bind or collapsing fully. You need at least a minimum amount of spring stiffness so it never collapses fully in the corner. For this reason I went up to Windtunnel Red cylindrical spring from the blue spring. Steering was superb. If I increased throttle 2/3 of the way into the corner, I could get the rear to slide out maybe an inch or two on hard power. This is where Barry was kicking the back end out on cornering so its where he likes to start adding power. I corrected with counter steer just like you would with a full size car. Anyway the steering is just right for me. I will race it. I can add more left down tweak with a stiffer spring to kill a little steering if I want. I went to a stiffer, stock silver, center spring to balance front and rear bump stiffness.

Motor Spacer
I found with my previous car that putting on a motor spacer 1/8 inch aluminum ring between the motor and the right side plate tightens the car. I added one. This also helped increase that left down tweak without such a huge spring preload.

Motor Forward
I ended up using 2.010 inch rear tires (almost used up). For this reason the motor ended up farther forward after gearing it correctly. On my previous car adding weight to the rear of the pod made the car ovesteer horribly. For this reason I think moving the motor (or weight) forward on the pod with a bigger pinion helps tighten the car. I need more tests here.

I am happy with the current setup. I'll post it after I race it. I was able to get a little rear wheel spin once in a while coming off the corner with the 13.5. What a thrill for this motor!

In the pic you can see. The high preload with the copper spring. The lightened motor spacer I used. The large pinion which moved the motor forward a bit.
John
Attached Thumbnails
CRC Battle Axe, GenXPro 10, 1/10th pan, Brushless, Lipo,4c, Road, Oval,TipsandTricks-left-down-tweak-setting-resized.jpg  

Last edited by John Stranahan; 06-09-2008 at 06:50 PM.
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Old 05-27-2008, 06:21 PM   #65
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John I didn't know I left my motor spacer in texas.. Guess I will be making a trip back.

You are right about moving the motor forward and farther from the axle. I am not tottaly sure why it works but I think it has to with the leverage the axle movement has to the motor movement reducing greater "unsprung" weight or less inerita to overcome for the pod/axle to respond to throttle or traction.
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Old 05-27-2008, 07:44 PM   #66
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Josh-Good to hear from you on this thread. Yes that would be your motor spacer and your tires. Should not leave them laying around. Josh is an experienced hand at the oval as well. He held our track record qualifying laps, briefly during a visit to Houston. Be glad to have you back. I may be faster with a Battle Axe. Thanks for the reinforcement on motor movement. I think the answer is more like this. A rear weight bias always causes oversteer because of the overloaded rear tires. That is the same trouble we fight with that huge left rear down tweak. My right rear only has about 3 ounces on it now.

Measuring Ackerman
I was asked to describe the method I used to measure Ackerman. I described Ackerman previously. Now the racer usually does not need to measure this, but it is a little like left down tweak. If you don't measure it you can't really share it with anybody with a different car.

Car on setup board. Set to 0 toe in. Board up against block or wall. Use rear width lines to center the rear (no extra spacers). Use any front opening to center the front with the center line on the board. Using tire edges will not center the front of the car due to different cambers left and right.

Use the combination square with an adjustable bevel attachment on the right front tire to set it to a convenient angle. 15 degrees is more than we use on the oval but it gives more precision on the measure. Now move the adjustable bevel and rule to the left side wheel and see what angle is there. You just rotate it until it is parallel to the wheel by eye. This is shown in the first photo. It helps to have a straight set of wheels on the car (or Darksides setup wheels, Eric send me a set and I will take a nice photograph of them).

The second pic shows the reading on this quick setup, 19.5 degrees. That is the measure stock. I have made a change to steering link angle by sweeping them back as they go out. A more accurately done setup showed 19.0 degrees with my angled links.

Now I also have a Browne and Sharpe dial protractor (photo 3), that could be used, that has more precision but generally your wheels are not perfectly straight. This Starrett combination square is also pricy but imported models from harbor freight are really cheap these days maybe $6 (no kidding). Imported dial protractors are also now available from Grizzly industrial. That's the only place I have seen them now. About $40.

Ackerman is related to the difference between the two angles you get. The second B & S measure gives me 19.07 degrees (19 degrees 40 minutes) on the inner wheel when the outer wheel is set at 15. I did this one more carefully compensating for a rear spacer. It agrees with the 19 I got previously using the bevel attachment.

And there you have it.

Ruggedizing the car
Final ruggedizing is complete. Blue Foam Bumper BSR, Steel screws on rear pivots. Steel ball nuts with thin washer on rear pivots, 6 plastic body post instead of aluminum. Heavy duty servo, Steel ballstuds with little Nylock nuts on the steering arms. The Aluminum ball nuts have no locking feature and wear quickly outdoors. The car is at 41.0 ounces with about as thin a tire as you can have. Perfect. I need to find a way to lock the steering arm to the steering block. These got loose. Maybe a longer screw with Nylock nut to prevent overtightening.
John
Attached Thumbnails
CRC Battle Axe, GenXPro 10, 1/10th pan, Brushless, Lipo,4c, Road, Oval,TipsandTricks-ackerman-measuring-006-resized.jpg   CRC Battle Axe, GenXPro 10, 1/10th pan, Brushless, Lipo,4c, Road, Oval,TipsandTricks-ackerman-measuring-004-resized.jpg   CRC Battle Axe, GenXPro 10, 1/10th pan, Brushless, Lipo,4c, Road, Oval,TipsandTricks-ackerman-measuring-b-s-dial-protractor-resized.jpg  

Last edited by John Stranahan; 05-28-2008 at 12:06 AM.
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Old 05-27-2008, 10:00 PM   #67
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I have good news. Frank owner of CRC has confirmed he will be sending me a Battle Axe for further long term testing. I'll send Ricks back to him early if I receive the new one in the next month or so. They are still not producing full runs of Battle Axes so it may take a while. Sale of GenX pro10's are keeping them really busy. Rick and I have an agreement for a couple months or whenever he decides he wants his bad boy back. It is hooked up at present. Maybe in the future we'll get hold of a GenX pro10 and give the thread a little more general flavor.
John
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Old 05-27-2008, 10:10 PM   #68
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KSG-lightweight left hand hub
Some of you may have spied this hub in a previous photo. Pardon the sacrilege of a blue part. It is indeed as light as it can be made. The screws have only about 3/16" of threads. Very light indeed. Slightly lighter than my homemade one because the screw heads are countersunk.

On first assembly I pushed the hub on hard with my palm to get it on. It was tight. I could not pull it off with my fingers unfortunately for the blue finish.

I pried it and got it off. The hub was undersize. I ran a 1/4 inch reamer through it to fix it. Now it fit well. Use locktite on only the threads of the screws. Don't let it accumulate in the sockets or the screw will be hard to back out.

Works OK other wise. Now barry does not believe that any of these lightening tricks actually work but then he commented how much punch the car had.

John

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Old 05-28-2008, 04:38 AM   #69
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Quote:
Originally Posted by John Stranahan View Post
I have good news. Frank owner of CRC has confirmed he will be sending me a Battle Axe for further long term testing. I'll send Ricks back to him early if I receive the new one in the next month or so. They are still not producing full runs of Battle Axes so it may take a while. Sale of GenX pro10's are keeping them really busy. Rick and I have an agreement for a couple months or whenever he decides he wants his bad boy back. It is hooked up at present. Maybe in the future we'll get hold of a GenX pro10 and give the thread a little more general flavor.
John

John ... keep it as long as you need to. We have an agreement and I have no problem with it.

Check your PM. Also can you PM me your regular email address.

Rick
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Old 05-28-2008, 08:43 AM   #70
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Quote:
Originally Posted by John Stranahan View Post
Maybe in the future we'll get hold of a GenX pro10 and give the thread a little more general flavor.
John

Yes please so us newbies can get our pan right on the money and get this class moving.

Thanks John for all the info provided, very helpful.
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Old 05-28-2008, 08:48 AM   #71
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expresso-Thanks. Don't forget the first 10 or so pages of the Pantoura thread this should be a help to anyone doing 1/10 pan on-road. This thread may have given some ideas for the final form of the GenX Pro 10.

Feel free to ask any road questions here as well. Lots of road guys look through the thread.
John

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Old 05-28-2008, 01:56 PM   #72
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In the vein of you have to finish to win. I continue my bulletproofing of the car. I had a pair of steering arm screws get loose already. The manual says not to tighten them very much. Here are some solutions so they don't get loose in a race. I puchased these graphite steering arms. Now I swear the web site photo showed a few different ballstud holes for changing ackerman; the photo is the same as my part now. That was my intent, to change ackerman. Instead they have one hole. The arm is shorter so some Ackerman change will result as the angle of my rearward raked steering links will change. I also got a set of longer screws and tiny nylock nuts that are used on the pivot ball. So here are two plans. Get the graphite. The screw holes are undersized so the screw threads a nice tight thread into them. You can now tighten the crap out of the tiny screw realizing of course that it is a tiny screw. Second plan. Use the stock steering arm but get two of these packages and then use a longer screw and a locknut. Trim the screw to size after instal with the Dremel cut off wheel. The road car may already come with this graphite arm. At least it is pictured in the manual.

A third plan at no cost is blue locktite. It will secure the screw to the upper hole and under the head.

Note I also went to a steel ball stud so that it would be locked. I had one of the aluminum ones get way loose. I used a short ballstud on the right and a tall ballstud on the left plus a washer thickness shim for proper bumpsteer. I discussed bump steer previously. I fine tuned it now here. I will trim off the extra steel threads.

More tuning parts came in. Plastic ride height adjusters, Reactive Caster blocks. A roll center kit. The roll center kit looks like it just duplicates the top clamps on the upper A-arm inner hinge pin but they must stack under the pin and then longer screws complete the assembly. I added titanium steering links and titanium pivot balls. This is to lighten unsprung weight a bit and also to have crash parts on hand. I'll note now that the lower A-arm fits both sides. Thats a nice feature. I have 1 spare on hand.

John
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Last edited by John Stranahan; 05-28-2008 at 02:57 PM.
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Old 05-29-2008, 05:14 PM   #73
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Track Report
93 F, Traction medium

On the last test there were two remaining problems. A little oversteer late in the corner on power that required countersteer and an occasional corner exit wheel spin. I added a little more wing, slightly bigger tire, small (spur and pinion) gears to move the motor back just a tad. The car was almost perfect now. I could add huge throttle about 2/3 the way into the corner and come out very straight with good traction.

I let Jeff the shop manager drive the car on the clock. I was calling out lap times. After only about 6 laps he was up to race speed. I noticed 2/3 through the corner that the car was slowing a bit (scrubbing off speed). I suggested he start adding throttle there. He ran the fastest lap of the day. We were not running record laps due to less than race day traction but were within .2 of the record laps in spite of some dust.

He thought maybe the car was scrubbing too much speed. I changed the ackerman back to stock by having the steering links leave the servo straight out. I did this on the big servo by putting the ballstuds on the back of the servo saver. Photo 1. I felt the scrubbing was reduced. Oval is a discipline where you will have to constantly reevaluate each setting to make tiny gains.

Photo two shows some delamination occuring on the top plate. No doubt this is probably from tapping the boards and over rotating the pod up to the stops. (bottoming the shock). This hole is unused and looks like it would hold an extra support to the bottom plate. There is a hole on the bottom plate as well. Anyway my advice is to put some hardware on the hole or eliminate the one on the top plate. Either way, will reinforce the top plate. I plan just to put a short flat head screw and nut and some superglue until a new part arrives. Notice the hole behind is well suported by the screw head and is holding up fine.

I added a set of titanium upper pivot balls. This is a fairly large custom piece of the pro strut suspension. The suspension will profit a little from the lower unsprung weight. I also added titanium turnbuckles. This is more for show, but they never bend either.

I had some contact now with the far right hand rear chassis screw and the track. I put some tape there. I will need to up the tension on the one remaining blue spring to limit the roll a little better and still have a low ride height. Race this Suday. I put on a red Wolfe side left side spring instead of tightening the blue spring.

John
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Last edited by John Stranahan; 05-30-2008 at 09:02 PM.
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Old 05-29-2008, 06:37 PM   #74
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Hi john,

Sounds like you're getting there. Sorry I won't be home to read your report Sunday knight.

I have a few questions:

What tires are you running and where on the car?

What traction compound are you using?

I know that running my Type R with foam tires, we use compound full rear and 1/2 on the inside of the front tires, what about running oval?

Could you or someone explain in the simplest form using Paragon and suntan lotion on foam tires?

What traction compound for rubber tires?

What servo do you replace mine with high torque or high speed?

It was a full size servo correct?
________________________________

John .... Should I order a new top plate from Frank?

I think I will have a set of BSR "R" Blue Net Compound Front #B2119, "S" Blue Net Compound Front #B2120, "L" Blue Compound Narrow Rear #B2027 & "S" Blue Net Compound Rear #B2123. If I get them would you want me to send then down to you?

Thanks,

Rick
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Old 05-29-2008, 07:48 PM   #75
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Glad to hear the CRC Gen-X Pro10 are selling!

I would add washers to that band-aide fix...more compression...
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