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Old 04-02-2009, 09:02 AM   #751
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Hey John, nice work on that bumper! That design could save a good bit of money with only the foam getting the brunt of the impact versus the carbon fiber bumper. I've gone through one bumper already... oof!

One question about the traction compound. I saw that you mixed paragon with jack the stripper and some suntan lotion. I was wondering, why not mix in WD40 or simple green? Why go with suntan lotion? I am just curious.
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Old 04-02-2009, 11:34 AM   #752
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Traction Compound talk for outdoor Asphalt

Harry-Thanks.

I have not done any mixing. The current procedure in some tracks in Florida is to use the liquid traction compound first, after about 10 minutes put on the suntan lotion on top then wipe it off before the race. I'll say yuck, it stinks up everything in the bag, performance is not better than Jack the Gripper alone throughout a 5 minute heat. Probably the worst part is having a rag all full of the product when you are done. Better to use paper towels and throw them away.

There was a report on the 1/10 thread that mixed about 20% Suntan Lotion in with his Jack the Gripper. He reported excellent results. If I can find an odorless product, I am going to try it.

There are good reasons why this may help. Tires are made of carbon black, rubber, oil. The % of oil softens the tire. The suntan lotion's oil may help. Jack the gripper is a solvent but the molecules are almost long chained enough to be a light oil.

I have tried simple green on rubber tires and it was only slightly effective. I have not tried WD40 on foams.

John

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Old 04-02-2009, 09:54 PM   #753
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Nerf Wing Continued, For Wide Gen X 10 with Stock Suspension

Here is the revision I was talking about. The Nerfwing has a little clearance cutout for the stock side link to keep it at stock height. To capture a couple of more screws it has been extended inward and replaces a small oblong graphite plate that the battery cover screws into. It will use the stock hardware. It includes a couple of extra holes in case sometime in your future you want to try that last 3-link suspension I made. If not just recontour the piece to omit the screws.

If you would like to buy one of these send me a PM. I don't have any made but I will look for a manufacturer, starting with CRC. If there is ony two of us then I will proceed with the 200 mm model of the part.

so what is it for:
It does the traditional task of protecting the rear axle. It is tapered so the car tends to slide off the object instead of catching and snapping the axle. I think it is beefy enough for the task. Once in a long while though its going to break.

You can run your electronics on the nerfwing for use on outdoor asphalt to move weight back. "You cannot have too much weight on the back of a powerful 2-wheel-drive." With the nerf wing you can also have the electronics low. The European guys had settled on two side by side 3 cell saddle packs back on the chassis as the best weight balance. This will mimic that weight balance with a 2s LiPo stick pack.

The outer bolt on this edition can take a washer underneath the nerfwing giving you more roll clearance. It already has 2.5 mm roll clearance just from the thickness of the chassis elevating it. I don't expect a problem here.

It will certainly give your wide pan a unique appearance.
Any comments welcome. I do have the prototypes installed on my wide pan. A test is coming soon.

The first view shows the fit of the part on the chassis. The scan was scaled and rotated to match a measured physical dimension. Then I went from there. Some holes may be off a few thousanths but the little graphite battery screw plate that we are removing seems to be off slightly more than this on my measure of the chassis and it fits fine. So this is the my best fit considering physical measures and the photo. I don't have access to the original chassis CAD.

the second view is annotated hopefully with sufficient dimensions for you to produce the part by hand. An accurate printing (not fit to page but 1:1) may produce an accurate print that can be rubber cemented onto the graphite.

the third view shows my use of the nerf wings to mount the electronics. This car has the 3 link conversion.

Note that the only critical dimensions are the placement of 3 holes that attach the plate to the chassis. You have to get these within .010 inch. With care and a drill press and a machinist rule you can get within .003 inch or so. Its OK if you have to dremmel the one outboard hole just a smidgen. The rest is Dremmel Sanding Drum accuracy. I use a diamond Dremmel blade to cut the graphite. It works super and does not snap on you and walks right through the stuff. I wear a respirator to cut and sand the graphite.

the screw holes are .114 inch diameter. The one larger hole is .175 which is a strange size. This hole takes the battery cover mounting screw inserts. The closest I could come would be a 1.85 mm drill at 1.74 inch. This is OK as a hole normaly increases .001 over drill size. A #17 at .173 inch could also be used. The outermost body post hole could use a 82 degree countersink on the bottom making the left and right plates sligtly different. This will improve roll clearance.
When and if you buy or make this part you will not need the extended body post side plates saving you that $17.

john
Attached Thumbnails
CRC Battle Axe, GenXPro 10, 1/10th pan, Brushless, Lipo,4c, Road, Oval,TipsandTricks-nerf-wing-stock-suspension001.jpg   CRC Battle Axe, GenXPro 10, 1/10th pan, Brushless, Lipo,4c, Road, Oval,TipsandTricks-nerf-wing-stock-annotated-suspension002.jpg   CRC Battle Axe, GenXPro 10, 1/10th pan, Brushless, Lipo,4c, Road, Oval,TipsandTricks-nerf-wings-electronics-install-resized.jpg  

Last edited by John Stranahan; 04-08-2009 at 06:29 PM.
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Old 04-03-2009, 07:39 PM   #754
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World GT, Petit Lemans Variant, Novak 10.5R, 2 s LiPo

45 mph on the straight by Radar with low traction. Sweet.

We had one racer that put his first on-road miles in that were not oval. He did well. It's not stupid fast. That is what that trigger on the radio is for. The speed suits the long track.

New goodies from CRC
http://teamcrc.com/crc/modules.php?n...article&sid=93
including Hard anodized ballnuts. I still think these should be the Losi steel part.
better side spring retention
better bumpers for the 1/12 scale
better beefier (hopefully more true) upper arms
center speed control mount for you 4 cell guys.
Beefy long side links. OK getting a little closer to a 3-link, maybe a year or two more wait?
Hard coated center pivot ball and molded holder for a no Dremmel install.

Still looking for the RC18T side shock set. Man they work well, and are twice the strength of the associated style on the ends. Imagine a smooth body set in red just like the RC18T shock to be used with the standard side springs.


We have 12 guys in our WGT group which has yet to race. At least 6 CRC Gen X 10's although there may be more at final count. I have not seen all the cars yet at practice.

John

Last edited by John Stranahan; 04-03-2009 at 10:24 PM.
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Old 04-04-2009, 03:12 AM   #755
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Hey John,

Could you post a picture showing how your front diffuser is attached to your body on the 235 mm pancar? I see some holes, and you mentioned using some spacers to get it on the right place. Do you use long screws that go through the body, the spacers, and the wing?
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Old 04-04-2009, 08:06 AM   #756
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Thomas
The fit of the HPI wing on the underside of the Peugeot HD is very good. Its as if this wing was used to make the mold. No spacers were needed on the back side. I used four 2 x 56 screws to mount the leading edge of the wing to the splitter. I used an extra nut between the body and the wing to space it properly. I then smooth the area with electrical tape. The tape on the leading edge will need to be replaced once in a while. Inside the car, again, no spacers, Just tape to smooth out the gap in the wing and the gap between the wing and the body.
On the non HD body, I used double sided tape to secure 3 body post plastic spacers between the back edge of the wing and the body, then tape. It is important to have part of the wing parallel to the ground so that you get airflow underneath without turbulence (laminar flow). As the air hits the next curved section it expands and the vacuum is created.

The other cloth seen underneath is fiberglass that is glued on with fabric glue. The glue dries clear, adheres very well and penetrates the cloth to reinforce the fender tire cutouts.
John
Attached Thumbnails
CRC Battle Axe, GenXPro 10, 1/10th pan, Brushless, Lipo,4c, Road, Oval,TipsandTricks-front-diffuser-peugeot-905-b-hd-001.jpg   CRC Battle Axe, GenXPro 10, 1/10th pan, Brushless, Lipo,4c, Road, Oval,TipsandTricks-front-diffuser-peugeot-905-b-hd-002.jpg  
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Old 04-04-2009, 05:32 PM   #757
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Traction compound...
i've been using 3 parts kingsford charcoal lighter fluid and 1 part suntan lotion (50spf) mixed in a can.. the lighter fluid is low oder and not offensive at all i think.. i massage it in once, leave it for the last 15 or so before i run then wipe it off.. stuck like chuck i tell ya and i get like a quart of the stuff for a few bucks...
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Old 04-04-2009, 07:55 PM   #758
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Tally-Glad you reported in here again. Thanks for the post. I selected a low oder hypoallergenic sunscreen. I shook and shook the mixture, but the two liquids were immiscible; the sunscreen went right to the bottom. If I shake vigorously I can get some of the sunscreen to stick in blotches onto the brush and some gets on the tire. It worked well, but not better. I need to try another brand.

Gen X 10 based wide pan test, Nerfwing test

Nothing like testing a brand new shiny car for the first time on the track. This car is equipped with a Novak 3.5 R motor and LRP TC edition speed control. Normal entry speed into the sweeper is about 53 mph.

I have of course made some changes. The CRC car is a Gen X 10 with their widening kit. The car wears my latest edition 3 link suspension. It required very few additional expensive parts except one pair of RC18T shocks which I would have put on the car anyway and a set of the finest looking sturdy red aluminum links I have seen from any manufacturer. Someone whined those are off-road links. Well they are not off-road links on my car, they are beefy on road links that mimic the ones on transam race cars. I note the brand new CRC 1/12 and 1/10 side links are beefy as well.

Forward traction was just outstanding on a low traction surface today for two reasons. One, the weight is put back on the rear using Nerfwings, and two the 3-link just does a better job at transfering weight back when you accelerate. The antisquat action is not all sucked out of play by a center shock extending. These two items take nothing away from the front grip which was provided by a standard CRC front suspension. After only a few laps I changed from CRC spec fronts to CRC purple fronts as I had to much steering traction for the loose conditions.

Nerf Wing Report
The nerf wings run the thickness of the chassis (2.5 mm) higher than the chassis as they are on top of it. I collected a few scratches to the rear corners. I put one Associated Aluminum #4 washer between the rear of the nerfwing and the chassis at the rearmost screw hole. This elevated the rear an additional 2 mm. It was perfect. Nice low rearward placed electronics with plenty of roll clearance. You cannot do this with a solid oval chassis with rear electronic pad. You basically have to jack the chassis up until that rearmost corner clears the track most of the time. The Nerf wings worked very well. It is a highly recommend.

World GT Report
I had a new guy with plenty of RC experience try out the Petit Lemans Edition World GT Car. 10.5 LiPo. His experience was plentiful and deep but was 8 years ago. It was very interesting wathching a normal guys months worth of pan car progression happen in one pack. It was a mighty long run mind you but not months. By the end of the pack he was finding my midstraight full throttle points on some of the short straights. The corner exit hook was solved quickly as I spoke of the slight pause for wheels to straighten. The slow throttle roll on talk cured the just after cornering midstraight spins. The speed on the straight increased by 15 mph at the end over the first few laps. Holding and adding a bit of throttle mid sweeper kept the car planted and cornering hard instead of dying and pointing inward. We may have another World GT racer.
first pic. You can just see that aluminum washer in the middle of the pic. It is raising the rear of the nerfwing an additional 2 mm.
second pic. Finished Nerfwing, but you can see the Panhard bar that locates the chassis left and right. We have a duplicate test going on in Quantes car. He is giving us good reports.
This shows the little graphite shock towers that were stolen from the center shock mount. The center shock is no longer needed.
fourth pic, the two verical shock dampen well the roll of the pod and use the standard side springs in bump and rebound now. They worked fine.
Fifth pic shows a lower shock mount. A hole needed to be drilled and countersunk here. Later the spring wass omitted and the stock side spring used. This gave the shock more tire clearance.

All these parts have been tidied up since the photos. There is no brass showing. All the chrome collars are the same size.

John
Attached Thumbnails
CRC Battle Axe, GenXPro 10, 1/10th pan, Brushless, Lipo,4c, Road, Oval,TipsandTricks-nerf-wing-after-shimming-003-resized.jpg   CRC Battle Axe, GenXPro 10, 1/10th pan, Brushless, Lipo,4c, Road, Oval,TipsandTricks-nerf-wings-finished.jpg   CRC Battle Axe, GenXPro 10, 1/10th pan, Brushless, Lipo,4c, Road, Oval,TipsandTricks-3-link-gen-x-10-pod-003.jpg   CRC Battle Axe, GenXPro 10, 1/10th pan, Brushless, Lipo,4c, Road, Oval,TipsandTricks-3-link-gen-x-10-pod-004.jpg   CRC Battle Axe, GenXPro 10, 1/10th pan, Brushless, Lipo,4c, Road, Oval,TipsandTricks-3-link-gen-x-10-pod-002.jpg  

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Old 04-04-2009, 08:09 PM   #759
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testing
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Old 04-04-2009, 09:36 PM   #760
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Quote:
Originally Posted by John Stranahan View Post
World GT Report
I had a new guy with plenty of RC experience try out the Petit Lemans Edition World GT Car. 10.5 LiPo. His experience was plentiful and deep but was 8 years ago. It was very interesting wathching a normal guys months worth of pan car progression happen in one pack. It was a mighty long run mind you but not months. By the end of the pack he was finding my midstraight full throttle points on some of the short straights. The corner exit hook was solved quickly as I spoke of the slight pause for wheels to straighten. The slow throttle roll on talk cured the just after cornering midstraight spins. The speed on the straight increased by 15 mph at the end over the first few laps. Holding and adding a bit of throttle mid sweeper kept the car planted and cornering hard instead of dying and pointing inward. We may have another World GT racer.

John
john, first off thank you very much for the ride today, as i thoroughly enjoyed it and it had been quite awhile. it was quite an experience picking up a remote after having been away from the hobby for 7+ years. it's amazing how fast it comes back...i'm almost amazed that i could still make it turn the correct direction still.

you just might have another racer in the wings. i actually broke out my old r/c stuff from the deep dark hole it'd been in, knocked off the dust and went through it all. if i can spare some time tomorow, i might come by and see if we can salvage any of my old and outdated stuff...

by the way, that old car measured 210m from tire to tire (outside edge) in the front and 232mm in the back...

-cameron
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Old 04-04-2009, 10:18 PM   #761
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Well good to meet you Cameron. I will be out tomorrow and we will take a peek. Sounds like RC10L dimensions within a couple of mm. That is what Ron is converting to 200 mm.
John
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Old 04-05-2009, 02:09 AM   #762
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Quote:
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Thomas
The fit of the HPI wing on the underside of the Peugeot HD is very good. Its as if this wing was used to make the mold. No spacers were needed on the back side. I used four 2 x 56 screws to mount the leading edge of the wing to the splitter. I used an extra nut between the body and the wing to space it properly. I then smooth the area with electrical tape. The tape on the leading edge will need to be replaced once in a while. Inside the car, again, no spacers, Just tape to smooth out the gap in the wing and the gap between the wing and the body.
On the non HD body, I used double sided tape to secure 3 body post plastic spacers between the back edge of the wing and the body, then tape. It is important to have part of the wing parallel to the ground so that you get airflow underneath without turbulence (laminar flow). As the air hits the next curved section it expands and the vacuum is created.
I'll have to see how I fit it to my Protoform Nissan body (which seems to be made from a bit thicker lexan than the Peugeots, so it needs less reinforcement). Probably need to use some larger spacers. One thing that is still unclear to me: by "inverted", you mean the wing is mounted with the back to the front, right?
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Old 04-05-2009, 04:21 AM   #763
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New 200 mm pan car from Germany !

Check rc devil, I can't post links.

Like it already, but I think it's a little bit expensive, around 600 $ ...
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Old 04-05-2009, 08:01 AM   #764
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grinta- Thanks for the post. I believe I commented on this car by private message. Here are some additional comments.

RC Devil

This is a very interesting Pan based on cars from Hazenbach. It has a dampened front end. The front suspension is mounted on a one piece flat graphite plates which pivots front to back on center pivot type balls. The pivoting motion allows the damping to occur at the rear of the plate. The plate also acts like a one piece sway bar (a la Corally)
At the rear barely visible is I believe, the latest Hazenbach 4 link rear end. Twin vertical links are aranged to lower the roll center by putting a virtual pivot at or below the ground. Additional angled links located the pod front and back. Some racers noted better rear cornering traction. Very innovative front and back end.
John
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Last edited by John Stranahan; 08-23-2009 at 07:56 AM.
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Old 04-05-2009, 08:13 AM   #765
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Quote:
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One thing that is still unclear to me: by "inverted", you mean the wing is mounted with the back to the front, right?
Thomas-I am mistaken. The wing is actually in the same orientation as it is on the back of the car. When I look at it I see the bottom of the wing. That caused my error. The bottom goes down however when the body is on the car. I will make corrections. Tell us how it performs.
john
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