Pantoura, 1/10 Pan Car, 2S LiPo, Brushless, Tips and Tricks.
04-14-2007, 05:21 PM
#1096
I prepped the track for Sundays race. It was a cool day in the fifties. I did not get the new car out until about dusk so there was some moisture on the track.
I had too much steering at first. I had noticed the night before that my roll center in the front was lower than on the other well setup car, so the first adjustment that I made was to raise the roll center a bit. I shimmed the lower A-arms up .025 inch. Took about 2 minutes. I loosened the screw to the lower aluminum bar. Slipped the nylon spacer under the screw with the needle nose pliers and then tightened them back up. The pic shows the space below the lower bar and the two washers can also be seen. I was pleased with the ease of adjustment. This fixed the car right up but may need another small change on a dry track. It was a very positive and predictable adjustment.
I tapped the flapper boards a couple of times due to the moisture. No damage to report.
The steering was very nice. Positive and Precise. No shudder apparent on my hairpins which the other car sometimes makes with new tires. I was using new front tires on the new prototype. Tomorrow in the race I will use some half worn tires. I plan to run the new prototype as it ran that good. Batism by fire. Should be well tuned by heat #3. I ran an old Peugeot 905B body. Note that I don't shroud the rear tires anymore as the high cornering g's cause rubbing.
This second prototype may see production. I am working out details with a manufacturer. Stay tuned. Don't delay a purchase based on this statement you can always sell a car and trade up if it becomes available.
Prototype comparisons
The two prototypes steered equally well when the parts were new. The first prototype then gradually lost steering over a couple weeks of use. The problem was wear on the lower outer pivot ball. I cured this with a $15.00 set of hardcoated pivot balls. Steering was back to very good. I suspect this front end won't degrade so quickly due to lack of pivot balls. First pic is the second prototype. Last pic is the first prototype front suspension.
I had too much steering at first. I had noticed the night before that my roll center in the front was lower than on the other well setup car, so the first adjustment that I made was to raise the roll center a bit. I shimmed the lower A-arms up .025 inch. Took about 2 minutes. I loosened the screw to the lower aluminum bar. Slipped the nylon spacer under the screw with the needle nose pliers and then tightened them back up. The pic shows the space below the lower bar and the two washers can also be seen. I was pleased with the ease of adjustment. This fixed the car right up but may need another small change on a dry track. It was a very positive and predictable adjustment.
I tapped the flapper boards a couple of times due to the moisture. No damage to report.
The steering was very nice. Positive and Precise. No shudder apparent on my hairpins which the other car sometimes makes with new tires. I was using new front tires on the new prototype. Tomorrow in the race I will use some half worn tires. I plan to run the new prototype as it ran that good. Batism by fire. Should be well tuned by heat #3. I ran an old Peugeot 905B body. Note that I don't shroud the rear tires anymore as the high cornering g's cause rubbing.
This second prototype may see production. I am working out details with a manufacturer. Stay tuned. Don't delay a purchase based on this statement you can always sell a car and trade up if it becomes available.
Prototype comparisons
The two prototypes steered equally well when the parts were new. The first prototype then gradually lost steering over a couple weeks of use. The problem was wear on the lower outer pivot ball. I cured this with a $15.00 set of hardcoated pivot balls. Steering was back to very good. I suspect this front end won't degrade so quickly due to lack of pivot balls. First pic is the second prototype. Last pic is the first prototype front suspension.
Last edited by John Stranahan; 04-25-2007 at 02:04 PM.
04-15-2007, 03:45 PM
#1097
Race Report-maiden run
Traction medium with poor (wet) patches
I qualified 3rd of 10 4wd Nitro sedans on the first heat. The wet patches were a problem for everyone, but when a two wheel drive gets one tire wet you tend to spin if you give it too much throttle. The tracked seeped out of some cracks from a heavy rain the previous day. As the day progressed conditions improved a little, but I had troubles. In the second heat I hit a wet patch on the end of the straight. This caused a bad spin on the sweeper and a hard crash into the boards. The spur was damaged and the front steering links had telescoped shorter as a result I dumped a lap before the finish.
Ball Cups
Now the front link problem can be avoided. I had purchased some heavy duty Losi long ball cups. It turns out that these round bodied ball cups have a tapered hole where the threads are, (these are pictured in a previous post) so it does not engage well unless you screw the tie rod in well past where all the threads are covered. They also don't fit the ball very snugly. Well. Don't buy these. Instead buy the hexagonal bodied Losi Truck ball cups. These are the best that I have found for a standard 4-40 ball. Or the short ones from the buggy if you don't need the extra length. The front suspension survived this crash directly on the right front as well as several contacts with the flapper board. I rememeber when I ran the touring car on this same track if you touched anything you would break a suspension component due to the high speeds.
Front Suspension Mounts
In the third heat I had another water related hard crash on the second lap. It broke the lower of my plastic suspension mounts (the fuse). The aluminum arms and the pins survided. The little cantilevered arm on the suspension block did not bend. The flexible parts did there job quite a few times and then failed with a severe crash. This was the intent. Next race I will try out the plastic arms. They have quite a bit more give. I did not pop any of the tiny e-clips. Well Roger actually could not see that it had e-clips.
Performance
I like the way the car handled.
After turn 6 and turn seven you make a fast transition mid next short straight from left turn to right turn and then from a right turn to left turn. The new prototype was very stable doing this. The previous prototype was a little twitchy as was the original Associated pan car suspension. The reason is the arms are slightly more even in length on this Prototype. Very close to what I run on my touring cars. Upper link only a little shorter.
Performance on the sweeper was very good. Wear on the left side tire was very even with a more reasonable camber of about 2 degrees. This is probably due to better camber control. The inside front tire on the sweeper had a cone pointy side inward. I reduced camber on this tire. The adjustment was easy as you can load the shims onto the two screws that secure the plastic suspension mount and then install the mount from the side with a standard hex driver.
I adjusted front ride height for tire wear with the shock collars. This is the way the gas guys do it. I like this. No performance penalty. At the rear after about 2 mm of wear I change the axle spacers to keep the pod from dragging. I can run this rear pod at about 2-3 mm as it has flat head screws underneath and it is not sprung.
Anyway things are looking promising for this second prototype.
The packs I ordered on Monday were not shipped until Thursday so I did not have my new packs to race with. I am averaging about 38 amperes over 5 minutes now. Imagine that with a 2 wheel drive. Motor temp was only 130F today. Air temp 70F.
The Toyota GT-1 body I ran today was a little bit forward on this older pantoura chassis due to differences between the old and new chassis. I will install a new body for the next race.
John
Traction medium with poor (wet) patches
I qualified 3rd of 10 4wd Nitro sedans on the first heat. The wet patches were a problem for everyone, but when a two wheel drive gets one tire wet you tend to spin if you give it too much throttle. The tracked seeped out of some cracks from a heavy rain the previous day. As the day progressed conditions improved a little, but I had troubles. In the second heat I hit a wet patch on the end of the straight. This caused a bad spin on the sweeper and a hard crash into the boards. The spur was damaged and the front steering links had telescoped shorter as a result I dumped a lap before the finish.
Ball Cups
Now the front link problem can be avoided. I had purchased some heavy duty Losi long ball cups. It turns out that these round bodied ball cups have a tapered hole where the threads are, (these are pictured in a previous post) so it does not engage well unless you screw the tie rod in well past where all the threads are covered. They also don't fit the ball very snugly. Well. Don't buy these. Instead buy the hexagonal bodied Losi Truck ball cups. These are the best that I have found for a standard 4-40 ball. Or the short ones from the buggy if you don't need the extra length. The front suspension survived this crash directly on the right front as well as several contacts with the flapper board. I rememeber when I ran the touring car on this same track if you touched anything you would break a suspension component due to the high speeds.
Front Suspension Mounts
In the third heat I had another water related hard crash on the second lap. It broke the lower of my plastic suspension mounts (the fuse). The aluminum arms and the pins survided. The little cantilevered arm on the suspension block did not bend. The flexible parts did there job quite a few times and then failed with a severe crash. This was the intent. Next race I will try out the plastic arms. They have quite a bit more give. I did not pop any of the tiny e-clips. Well Roger actually could not see that it had e-clips.
Performance
I like the way the car handled.
After turn 6 and turn seven you make a fast transition mid next short straight from left turn to right turn and then from a right turn to left turn. The new prototype was very stable doing this. The previous prototype was a little twitchy as was the original Associated pan car suspension. The reason is the arms are slightly more even in length on this Prototype. Very close to what I run on my touring cars. Upper link only a little shorter.
Performance on the sweeper was very good. Wear on the left side tire was very even with a more reasonable camber of about 2 degrees. This is probably due to better camber control. The inside front tire on the sweeper had a cone pointy side inward. I reduced camber on this tire. The adjustment was easy as you can load the shims onto the two screws that secure the plastic suspension mount and then install the mount from the side with a standard hex driver.
I adjusted front ride height for tire wear with the shock collars. This is the way the gas guys do it. I like this. No performance penalty. At the rear after about 2 mm of wear I change the axle spacers to keep the pod from dragging. I can run this rear pod at about 2-3 mm as it has flat head screws underneath and it is not sprung.
Anyway things are looking promising for this second prototype.
The packs I ordered on Monday were not shipped until Thursday so I did not have my new packs to race with. I am averaging about 38 amperes over 5 minutes now. Imagine that with a 2 wheel drive. Motor temp was only 130F today. Air temp 70F.
The Toyota GT-1 body I ran today was a little bit forward on this older pantoura chassis due to differences between the old and new chassis. I will install a new body for the next race.
John
Last edited by John Stranahan; 04-15-2007 at 08:38 PM.
04-15-2007, 04:28 PM
#1098
Trinity N60 testing
Did some testing: comparing lap times; Trinity N60 with the Novak 3.5R. The Trinity N60 Weighed in at 158g, while the Novak 3.5R came in at 190.4g. Ran 3 heats of 6 minutes each, and compared lape times. Car has same exact set-up through out, including same weight- no fans on motors, only heat sinks.
heat 1
Trinity N60: average lap: 13.58, temp: 152F
Novak 3.5R: average lap: 13.69, temp: 168F
Heat 2
Trinity N60: average lap: 13.54, temp: 154F
Novak 3.5R: average lap: 13.66, temp: 170
Heat 3
Trinity N60: average lap: 13.536, temp: 155
Novak 3.5R: average lap: 13.658, Temp: 171
******************************************
The results show that the N60, maybe due to its weight advantage is faster than the 3.5R, plus runs cooler...less wear and manitanance in the end, and longer run times...its a Keeper!!!
heat 1
Trinity N60: average lap: 13.58, temp: 152F
Novak 3.5R: average lap: 13.69, temp: 168F
Heat 2
Trinity N60: average lap: 13.54, temp: 154F
Novak 3.5R: average lap: 13.66, temp: 170
Heat 3
Trinity N60: average lap: 13.536, temp: 155
Novak 3.5R: average lap: 13.658, Temp: 171
******************************************
The results show that the N60, maybe due to its weight advantage is faster than the 3.5R, plus runs cooler...less wear and manitanance in the end, and longer run times...its a Keeper!!!
04-15-2007, 07:06 PM
#1100
Originally Posted by John Stranahan
YYhayyim-nice report. I ordered one of those Trinity motors. I will have to wait for the Tekin R1Pro to test it. I should have new batts by then as well.
John
John
On my pan cars, that's the ticket for me now after testing. The Mamba and the N60 is just the best combo so far, and gives me a weight reduction of almost 35g over the Novak and LRP system, which for pan cars is very significant, especially in the noticable punch and quicker launch of the line and accelaration, as well as top speed and corner speed...I cant wait to test the R1 PRO and the Trinity N60! That combo should offer about 60-65g in weight reduction over the Novak/LRP combos...WOW!!
04-15-2007, 07:43 PM
#1101
I'd be interested in seeing a thorough test of the GM Genius 95 (or 100) with its motors, and the others. The ESC apparently has a hybrid mode where when it detects a motor with a Hall sensor, it will drive it in both sensored and sensorless mode, depending on the RPM. Marc Fischer used the GM ESC with the GM motor to win the Snowbirds.
What's the source of the Trinity motor? To my knowledge, they just slapped their sticker on someone else's stuff. I can't bring myself to ever support their brushless endeavors after their anti-brushless campaign in the past.
What's the source of the Trinity motor? To my knowledge, they just slapped their sticker on someone else's stuff. I can't bring myself to ever support their brushless endeavors after their anti-brushless campaign in the past.
04-15-2007, 08:19 PM
#1102
YYHayyim-Thanks for the added detail. Better performance in the heat would be a definite plus. It is not hot yet. At what air temp were your test performed. Azmio is running at over 120F. In August our track temps will be 140-150 F. If I fry the Tekin I'll try a Mamba.
Syndrome-I don't know the source. No body makes motors much over here in the states anyway. They are all sourced somewhere else as far as I know. You take this PR stuff (what I call those lying dogs) too seriously as do I.
And speaking of lying dogs. One maker claims his brushless motor puts out 1000W at 7.4 V. Well if it did you could probably feel the heat on your face from the incandescent motor case when you popped the body off. Then you pop one in your RC car and they are maybe a tiny bit faster that a brushed that has a dynoed output maximum, of 240 W. Aveox used to make similar claims in the early days of brushless. We put an early Aveox (with a huge power claim) in a mod truck and it was slow. I actually think that all of these motors that claim over 600 Watts are using the same crummy motor theory to calculate power output that I have used myself (there is a old Turbodyno thread with every horrid detail of the calcualtions on RC-tech). It is not real output. It is a theoretical output. It is not measured on a dyno. Novak talks of testing their motors on a dyno but they don't really give any details about the beast. I suspect it does not really measure output power or they would report it. I am glad that Novak simply reports the K(v) or kiloRPM per Volt. That is what they measure and this is the honest thing to report.
John
Syndrome-I don't know the source. No body makes motors much over here in the states anyway. They are all sourced somewhere else as far as I know. You take this PR stuff (what I call those lying dogs) too seriously as do I.
And speaking of lying dogs. One maker claims his brushless motor puts out 1000W at 7.4 V. Well if it did you could probably feel the heat on your face from the incandescent motor case when you popped the body off. Then you pop one in your RC car and they are maybe a tiny bit faster that a brushed that has a dynoed output maximum, of 240 W. Aveox used to make similar claims in the early days of brushless. We put an early Aveox (with a huge power claim) in a mod truck and it was slow. I actually think that all of these motors that claim over 600 Watts are using the same crummy motor theory to calculate power output that I have used myself (there is a old Turbodyno thread with every horrid detail of the calcualtions on RC-tech). It is not real output. It is a theoretical output. It is not measured on a dyno. Novak talks of testing their motors on a dyno but they don't really give any details about the beast. I suspect it does not really measure output power or they would report it. I am glad that Novak simply reports the K(v) or kiloRPM per Volt. That is what they measure and this is the honest thing to report.
John
Last edited by John Stranahan; 04-15-2007 at 09:24 PM.
04-15-2007, 09:51 PM
#1103
Originally Posted by John Stranahan
Syndrome-I don't know the source. No body makes motors much over here in the states anyway. They are all sourced somewhere else as far as I know. You take this PR stuff (what I call those lying dogs) too seriously as do I.
04-16-2007, 06:46 AM
#1104
[QUOTE=John Stranahan]YYHayyim-Thanks for the added detail. Better performance in the heat would be a definite plus. It is not hot yet. At what air temp were your test performed. Azmio is running at over 120F. In August our track temps will be 140-150 F. If I fry the Tekin I'll try a Mamba.
Tests were done at 84F air temp, and 105-110 track temp; In the summer it gets arund 94-95F air temp and about 140F track temp. That's why I chose to do it with out cooling fans on the motors, only heat sink, to put more pressure on the systems...but on hotter weather, fans on the motors should keep them cooler. That's were the Mamba system shines...since there are no thermal issues, you dont have gear down to run cooler and thus loose your top-end. You gear for temperature with the Mamba, where as with the Novak system and LRP's I'd have to gear down to avoid thermals in hotter weather...well, that's all for now. Keep up the good work John!
Tests were done at 84F air temp, and 105-110 track temp; In the summer it gets arund 94-95F air temp and about 140F track temp. That's why I chose to do it with out cooling fans on the motors, only heat sink, to put more pressure on the systems...but on hotter weather, fans on the motors should keep them cooler. That's were the Mamba system shines...since there are no thermal issues, you dont have gear down to run cooler and thus loose your top-end. You gear for temperature with the Mamba, where as with the Novak system and LRP's I'd have to gear down to avoid thermals in hotter weather...well, that's all for now. Keep up the good work John!
04-16-2007, 11:05 AM
#1105
castle creations (mamba), novak and tekin are all made in the USA..
from novak
from tekin
castle says all their controlers are made in the usa, not sure about their motors..
the only reason i chime in is that i take pride in buying as much as i can from us companies with manufacturing capacities...
from novak
Novak is a self-contained R/C manufacturer proud to design and build their products on-site in the USA.
Our State of the Art ISO9001 certified manufacturing facility is proudly located
here in the USA
here in the USA
the only reason i chime in is that i take pride in buying as much as i can from us companies with manufacturing capacities...
Last edited by tallyrc; 04-16-2007 at 11:30 AM.
04-16-2007, 12:03 PM
#1106
I put plastic front arms on the car and weighed it. 41.5 ounces Ready to race. Some of the front end screws could be changed to aluminum to cut a few grams. The Tekin R1 Pro and N60 motor should cut some weight as well. Note that this chassis is bigger than the newer one. And the receiver is the large size. Both of these are probably worth an ounce.
I moved my front roll center up during the race. I moved the inner steering link pivots back to the original higher holes in the large servo saver to correct bump steer. I still have two different upper inner A-arm mounts. I am waiting on parts to correct this situation.
John
I moved my front roll center up during the race. I moved the inner steering link pivots back to the original higher holes in the large servo saver to correct bump steer. I still have two different upper inner A-arm mounts. I am waiting on parts to correct this situation.
John
Last edited by John Stranahan; 04-16-2007 at 12:43 PM.
04-16-2007, 01:10 PM
#1107
I added some text and a photo to my . post above.
Body Fit on New Front Suspension
Here are a couple of pics where you can see the fit of the body on the new front suspension. This is the Associated Nissan body. I have put the top of the front splitter even with the front edge of the chassis. The front wheels are centered on the front wheel cutouts marked into the body. There is clearance on the baby shock tower on this body. The upper front arms are lower inboard than the previous front suspension. They have clearance on the body at full bump with a new tire. The new tire will just have clearance on the upper inner wheel well at full bump. The Peugeot and Toyota GT-1 bodies will actually rest on the front baby shock towers at a good height. The bodies will then clear the top of the shocks due to hood curvature. The clearance is intentionally zero on the shock tower here to have a better shock angle. Clearances came out nice.
John
Body Fit on New Front Suspension
Here are a couple of pics where you can see the fit of the body on the new front suspension. This is the Associated Nissan body. I have put the top of the front splitter even with the front edge of the chassis. The front wheels are centered on the front wheel cutouts marked into the body. There is clearance on the baby shock tower on this body. The upper front arms are lower inboard than the previous front suspension. They have clearance on the body at full bump with a new tire. The new tire will just have clearance on the upper inner wheel well at full bump. The Peugeot and Toyota GT-1 bodies will actually rest on the front baby shock towers at a good height. The bodies will then clear the top of the shocks due to hood curvature. The clearance is intentionally zero on the shock tower here to have a better shock angle. Clearances came out nice.
John
04-16-2007, 01:21 PM
#1108
Originally Posted by John Stranahan
... I am averaging about 38 amperes over 5 minutes now. Imagine that with a 2 wheel drive. Motor temp was only 130F today. Air temp 70F.
John
John
That's insane. Assuming the battery can hold 7 volts, you are putting out an average of 266 watts. SICK, just SICK.
04-16-2007, 05:29 PM
#1109
Rollout
Quick question on rollout. I just put a mamba max with 4600 motor in my 10L2. My rollout as of now is 32.5 15/87 with 60mm tires. I have not tried it yet. Where do you guys think I should be.
This is the track I'll be running on
Thanks
This is the track I'll be running on
Thanks
04-16-2007, 07:24 PM
#1110
Linger- I was wondering if someone would notice. That is quite a bit of power being put down by two wheels.
Doug- Nice photo and track. I see that you might have some dust problems there. Do you guys ever treat the track surface?
The Kv rating on that Mamba motor is 4,600. This makes aproximately equivalent to a Novak SS Pro 8.5 Kv=5000 or a 15-17 turn brushed motor. I have not run this power of motor in my pan, but with this information maybe somebody else will give you a suggested gearing.
John
Doug- Nice photo and track. I see that you might have some dust problems there. Do you guys ever treat the track surface?
The Kv rating on that Mamba motor is 4,600. This makes aproximately equivalent to a Novak SS Pro 8.5 Kv=5000 or a 15-17 turn brushed motor. I have not run this power of motor in my pan, but with this information maybe somebody else will give you a suggested gearing.
John