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Old 07-13-2009, 10:01 PM   #946
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Originally Posted by Fabricio View Post
John,

I am new to the pan car world, I bouhgt my Gen X10 a few months ago but just now I am able to run it.

I have read some of the posts specially the one about the lock nut of the diff, I have ordered the blue associated ones.

One thing that I am not understanding is, the gearing and the roll out thing.

I am going to use the car not for competition, but I am going to be running on a proper track, asphalt track.

I am planning to use the tires as they come out of the box, can I do that?

I am going to run a Xerun 120A Esc with a 8.5T motor, it is a combo from Hobbywing.

I would like to have some help on how to calculate the roll out of the car, and one thing that I did not understand untill now, is how do I set the proper roll out? Is it going to depend on the track or motor? What is the point?

I have learn how to calculate it but I did not understand how to use it properly.
http://www.rcracing.com/Gear_Ratio_Program_1100.cfm

This should help.
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Old 07-14-2009, 08:34 AM   #947
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Fabricio- the calculator Lidebt2 posted should give you some numbers. I will add a little "color". When you drive a full size car you have several gears to choose from. You select a high gear (say 5) for running at high speed and a low gear (1) for accelerating from a stop. Our electric cars have only one gear so we have to choose it carefully to give us the best balance between running at high speed and starting from a stop. More teeth on the pinion gives you a high gear. Fewer teeth on the pinion gives you a low gear.

I use this gearing chart at Novak to get you a starting point. They suggest 1.4 inch roll out for a 1/10 pan car. (new tires are fine).

tire circumference is 2.4 x 3.14 = 7.536 in

circumference/roll out =7.536/1.4 = spur pinion ratio = 5.38

lets say you have a 90 spur in 48 pitch

90/5.38 gives us the number of pinion teeth. 17

Give it a 3 minute run. Measure the motor temp. The temp needs to be at or below 190 F. After a while you will get the feel of the car. fewer teeth will give you more punch and acceleration out of the corner. More teeth will soften the car and give you a little more top speed. If the temp is OK at 3 minutes then finish the run and measure temp again.
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Old 07-14-2009, 08:45 AM   #948
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Quote:
Originally Posted by John Stranahan View Post
Fabricio- the calculator Lidebt2 posted should give you some numbers. I will add a little "color". When you drive a full size car you have several gears to choose from. You select a high gear (say 5) for running at high speed and a low gear (1) for accelerating from a stop. Our electric cars have only one gear so we have to choose it carefully to give us the best balance between running at high speed and starting from a stop. More teeth on the pinion gives you a high gear. Fewer teeth on the pinion gives you a low gear.

I use this gearing chart at Novak to get you a starting point. They suggest 1.4 inch roll out for a 1/10 pan car. (new tires are fine).

tire circumference is 2.4 x 3.14 = 7.536 in

circumference/roll out =7.536/1.4 = spur pinion ratio = 5.38

lets say you have a 90 spur in 48 pitch

90/5.38 gives us the number of pinion teeth. 17

Give it a 3 minute run. Measure the motor temp. The temp needs to be at or below 190 F. After a while you will get the feel of the car. fewer teeth will give you more punch and acceleration out of the corner. More teeth will soften the car and give you a little more top speed. If the temp is OK at 3 minutes then finish the run and measure temp again.
John, thank you very much, I will do that this weekend and see how it goes.

I was wondering if there is any set up tool available for pan cars?How do you guys set up front camber and toe out?
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Old 07-14-2009, 09:14 AM   #949
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There is a super nice camber setup tool that integy imports. Camber will be set between -1 and -1.5 degrees to make the tire wear flat. For a long time I just put a coke can up against the wheel and eyeballed the gap or used drill bits to put in the gap I wanted, like 1/16 inch. (Camber equal arctan(.062/2.4)=1.4 degrees)

I use inside friction joint calipers to set toe in to 0. You can also eyeball or use a rod of known diameter to create a space in the rear of an exact dimension to make toe-in. For example a 1/8 inch drill will give 1.4 degrree toe in if it can slip between the gap betwen tire and caliper point at the back of the wheels. I don't use toe in or toe out on the pan. Rarely on the touring car.

http://www.mcmaster.com/#1962a31/=2qqjtk

The following model is called a Hermaphrodyte caliper and can be used to transfer measurements from a ruler to a small part to be cut. I invert the needle and use it like the inside caliper above to check toe in. Both of these tools sit very flat and take up little space in a tool drawer of a tackle box. Starrett quality is not needed here.

http://www.mcmaster.com/#1963a32/=2qqk7z

I particularly dislike setup tools that make you take the wheels off between heats. You have more important things to do.

Associated and others make nice ride height gauges. Start at 6 mm outdoors.

Get a flat board to setup the car. I like the Integy model with the nice decal surface. It lets you do more elaborate checks like to see if your rear axles are equidistant from the car center. I imagine there are a lot of people running with this off a little. Replacement decals are available once in a while. These can just be glued on to your piece of flat material.
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Last edited by John Stranahan; 07-14-2009 at 09:28 AM.
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Old 07-14-2009, 05:14 PM   #950
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John and folks, I have some exciting news! We now have a new asphalt track as of yesterday, yes it is a dream come true. My car had tons of traction and will be making this track home. Open 7 days a week and 15 minutes away from home. Anyways here are some pics and videos of both the on road and off road tracks.

http://www.rctech.net/forum/6062176-post614.html
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Old 07-14-2009, 10:59 PM   #951
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Dam, and you sold all your good stuff! Super nice track. INDOORS. SWEET. Better work on getting a crowd there.
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Old 07-14-2009, 11:11 PM   #952
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Quote:
Originally Posted by espresso1967 View Post
John and folks, I have some exciting news! We now have a new asphalt track as of yesterday, yes it is a dream come true. My car had tons of traction and will be making this track home. Open 7 days a week and 15 minutes away from home. Anyways here are some pics and videos of both the on road and off road tracks.

http://www.rctech.net/forum/6062176-post614.html
Nice video. Thanks.

You SoCal guys deserve a nice track...and you only need to support it.
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Old 07-14-2009, 11:14 PM   #953
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Nope did not sell anything. My pan is a keeper and after today it has been confirmed that it is not going anywhere

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Dam, and you sold all your good stuff! Super nice track. INDOORS. SWEET. Better work on getting a crowd there.
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Old 07-16-2009, 08:51 AM   #954
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New Stuff from CRC

4 mm pod top plate
#1765. The first pic shows this heavy duty top plate for the Gen X 10 pod. There are a couple reasons why you might install this part. 1. you have broken your original size top plate. The new plate will resist breakage. 2. you are having some problems with gear longevity (strippage) on a powerful wide pan. The new top plate will help stiffen the pod. A second item which may help this is under development but may be available by e-mail. It is a stiffer bottom plate. It gains it stiffness from wider sections. I know this exists, I don't really know if it is available.
Note that this car is a 3 link. I have made some changes since I last photographed it. I abandoned the tweak springs for main springs as the travel was too limited. I added coil over shock springs. This gold RC18T front spring is especially well suited to the back of a wide pan.

New Battle Axe 2.0
Attached Thumbnails
CRC Battle Axe, GenXPro 10, 1/10th pan, Brushless, Lipo,4c, Road, Oval,TipsandTricks-pod-top-plate-4mm.jpg   CRC Battle Axe, GenXPro 10, 1/10th pan, Brushless, Lipo,4c, Road, Oval,TipsandTricks-ba2.jpg  
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Old 07-18-2009, 11:21 PM   #955
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Next Generation 3-link Wide Pan

This car is similar to my white wide pan in that it has a 3-link rear suspension and a dual A-arm front end. Similarities end there. The chassis is different as is the pod, shock mounts, panhard bar mounts. This is the latest of my wide pans.

Improvements include rear axle Remove and Replace with no interference from the side links or shocks. This helps tinkering with gearing and adjusting rear pod height. Another big improvement is ease of manufacture. In the rear all the parts exist and are simply arranged differently. In the front only three custom graphite plates need be produced which along with CRC Pro strut front end parts produce a very rugged dampened dual A-arm front end.

My cooling vents on the white car were so succesful that I wanted to reproduce them on this car. I moved the speed control to a position held by the radiator in the full size 905 b car. I cut a new longish rectangular opening in the body. I covered it with the blister pack from winshield wiper blades. The front of the scoop cools the speed control with 65 mph air every lap, the rear has an extension downward and cools the solder tab end of the motor. I may paint the vent like the body and see how it looks later. I like it OK in clear. The side to side balance was within .2 ounces as the receiver is held far right on a Nerf wing while the speed control is moved to center. The rear weighs 4 ounces more than the front. The total weight with a 6000mA-h SMC hard case LiPo on board is 45.1 ounces. Ready to rip. The track was 145F today. I will test tomorrow if possible.

I was able to mount the body as low as on a standard pan due to improvements in rear shock location and upright, as well as a more compact 3 link arrangement using the stock top plate off the Gen X 10 (I have used the thicker optional top plate however).
Attached Thumbnails
CRC Battle Axe, GenXPro 10, 1/10th pan, Brushless, Lipo,4c, Road, Oval,TipsandTricks-next-generation-3-link-wide-pan.jpg  
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Old 07-19-2009, 02:00 AM   #956
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a pic of the chasis would be appreciated
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Old 07-19-2009, 07:29 AM   #957
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Next Generation 3-link Pro 10

click on the enlarged pic again and hit your full screen box for the sharpest view.

Pic 1 shows the slightly elevated position of the speed control which has been moved from the left nerfwing to a platform made out of a spare side plate. This puts the heatsink up into 65 mph air each run and keeps it cool without a fan. Side to side balance is outstanding now.

Pic 2 you can just see the right side end of the Panhard bar which is attached to a hole drilled and threaded in the lower front of the motor mount plate. You can also see the new 4 mm top plate. I used a standard tube standoff instead of hour glass standoffs at the front of the top plate now to gain additional clearance in the middle of the Panhard bar.

Pic 3 shows the dual A-arm front end. A copy on the white pan car worked extremely well on our new Asphalt. CAD and Kit to come.

Pic 4 shows that things are kept fairly low on this version of the Pro 10

Pic 5 is a view of the left rear of the motor area from the back. It shows a flattened ball cup which is the left side of the Panhard bar. The left side mount has been moved a little outward to the inboard side plate support to lengthen it and give this ball cup more clearance. I was able to mount a 96/14 gear with clearance now.
Attached Thumbnails
CRC Battle Axe, GenXPro 10, 1/10th pan, Brushless, Lipo,4c, Road, Oval,TipsandTricks-next-generation-3-link-wide-pan-001.jpg   CRC Battle Axe, GenXPro 10, 1/10th pan, Brushless, Lipo,4c, Road, Oval,TipsandTricks-next-generation-3-link-wide-pan-002.jpg   CRC Battle Axe, GenXPro 10, 1/10th pan, Brushless, Lipo,4c, Road, Oval,TipsandTricks-next-generation-3-link-wide-pan-003.jpg   CRC Battle Axe, GenXPro 10, 1/10th pan, Brushless, Lipo,4c, Road, Oval,TipsandTricks-next-generation-3-link-wide-pan-004.jpg   CRC Battle Axe, GenXPro 10, 1/10th pan, Brushless, Lipo,4c, Road, Oval,TipsandTricks-next-generation-3-link-wide-pan-005.jpg  

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Old 07-22-2009, 03:26 PM   #958
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Nerf Wings and Shortie Bumpers
from
Powell Racing Components

Just Completed.

I had four prototype sets of nerf wings and shortie bumpers made for the CRC Gen X 10. Doug Powell agreed to do the job in time for me to give them out as prizes at our Inaugural World GT Petite Le mans (3800 Orion, Novak 10.5, World GT cars) race on August 1 2009 starting at 11:00 AM at Mikes-HobbyShop.com on the newly resurfaced 1/8 scale track. Similar parts may be underway at CRC.

Here is the anticipated benefit of the new parts.

Nerf Wing
This will protect the rear axle and pod. I anticipate much greater strength from the angled contact that will result. I have left plenty of unventilated graphite to prevent Nerf wing breakage. 3 existing holes in the chassis will be used to bolt it down securely. The nerf wing will replace one battery tray support plate. It will prevent the links from pulling the ears off the pod in a side crash to the boards by soaking up the impact. I made it to use the short links, which I prefer now as they put less stress on the pod ears (holes). In a similar manner the axle will be protected from intrusion type crashes to the side and side crashes into the board. The body will just cover the outside edge of the wing.

Secondly if you race on asphalt every scrap of weight you put back helps your forward traction out of the corners. It improves your lap time. It helps you penetrate the dust. With the Nerf wings installed you can mount electronics as far back and as low as possible. Roll clearance will be obtained with one or two washers of shim under the outer bolt and rearward bolt. Pics to come.

Thirdly if you want to tinker there are two sneaky extra holes that will get you a great start on a 3-link rear end like the car pictured in my previous post.

Shortie bumper
CRC sells a very fine high density foam bumper. This graphite bumper is cut narrower and shorter so that the high density foam has enough crush distance to do its job. This bumper leaves .75 inch of front overhand on the foam bumper. Rigid body post positions on the two outside holes are possible. Use plastic post here for the best strength.

The parts came out very nice. Doug does some nice work! We have one small revision to the nut insert hole and then its a go. The parts will be roughly $20 each. This is still being worked out. I am quite proud of sending out the CAD that led to these nicely machined parts. Thanks to Frank at CRC for such a nice platform to hop up.

Click the pic a second time after it enlarges for a bigger sharper view.
Send Doug an e-mail request, [email protected], if you want the parts. I will send in a very slight correction tomorrow to allow a better press fit of the threaded insert. I plan to race the Nerf wings August 1.

I have no profit from these so this is just a new product review.
Attached Thumbnails
CRC Battle Axe, GenXPro 10, 1/10th pan, Brushless, Lipo,4c, Road, Oval,TipsandTricks-nerf-wing-shortie-bumper.jpg  
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Last edited by John Stranahan; 07-22-2009 at 10:34 PM.
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Old 07-22-2009, 03:48 PM   #959
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Those nerve wings looks great John and so does the bumper. I'll see if I can come watch the august 1st race at Mikes.
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Old 07-22-2009, 04:36 PM   #960
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snellemin-thanks, look forward to seeing you. Heck bring a car and race. We could have a wide pan exhibition between heat 1 and 2.



Shortie Bumper Install

Ref: My Previous Post

install short CRC aluminum standoffs by pushing them into the bumper holes that match the two existing holes in the bumper. Attach CRC foam bumper to the shortie graphite bumper with button head screws on the bottom and red flat head aluminum screws with decorative reverse cone washers (Axial 3 mm). With a .112 drill in a hand drill, drill 4 additional holes in the bumper. Two for Body posts. And two more for short standoffs. Remove bumper. Re drill the body post hole larger for the post you plan to use. The post will still need to be wet with soapy water to be pushed in. Install the two lower body post body pins to hold that bumper in a side crash. Now remount the foam bumper on the graphite bumper. Mount the graphite bumper on the car. I suggest at least two black steel screws here. Your ready to go. Trim bumper as needed for a low body. The Dremmel large sanding wheel seems to work good for me.

Note this will fit the Battle AXE as well. All of my oval racing buddies needed this bumper at Mikes. Would have saved a lot of breakage and expense and drivers quiting in frustration. Can't wait to see it on a new kit. In the meantime give Doug Powell and e-mail

[email protected]

. See my previous post.

Nerf wing install
The only tips here are to use some washers between the Nerfwing and Frame on the rear most and outermost hole to tilt the back of the nerfwing up when viewed from the side and the side of the Nerf wing up when viewed from the front. This will give a little more ground clearance while still allowing very low mounting of any ballast and electronics. The 4-40 press in threaded insert will go into a slightly tighter hole than the original. I had one kit insert come loose in use. Use a hammer with the nerfwing on a solid piece of steel or use a small piece of flat metal underneath and a vice grip pliers to gently force it into place. As added insurance you can superglue the perimenter from the bottom.
Attached Thumbnails
CRC Battle Axe, GenXPro 10, 1/10th pan, Brushless, Lipo,4c, Road, Oval,TipsandTricks-shortie-bumper-install-gen-x-10-001.jpg   CRC Battle Axe, GenXPro 10, 1/10th pan, Brushless, Lipo,4c, Road, Oval,TipsandTricks-shortie-bumper-install-gen-x-10-003.jpg   CRC Battle Axe, GenXPro 10, 1/10th pan, Brushless, Lipo,4c, Road, Oval,TipsandTricks-nerf-wing-install-004.jpg   CRC Battle Axe, GenXPro 10, 1/10th pan, Brushless, Lipo,4c, Road, Oval,TipsandTricks-nerf-wing-install-005.jpg  
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Last edited by John Stranahan; 07-22-2009 at 10:33 PM.
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