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Old 06-08-2007, 03:10 PM   #1426
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That is quite a difference. Well over 70K RPMs on a normal battery pack let alone the LiPo batts your running. That is going to be rough on any type of bearing you put in there no matter what the gearing.
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Old 06-09-2007, 02:01 AM   #1427
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yeah, 3.5 T is really cool on straight line. However, coming out of corner can be a big headache especially when the traction compound has been eaten up. It teaches me to be soft on throttle and necessitate a nice race instead of hard braking.

I do feel that 5.5 T may be enough provided that the pan car is properly tuned for the track. When the 1/8 or top 10% 1/10 nitros are on the track, almost always that you will end up with either 4.5 or 3.5.

This morning, I had 3 or my kimbrough spurs worn out. Too much power but that's what you need to race with the nitros.
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Old 06-09-2007, 03:12 AM   #1428
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Hmm, if thatīs true than our 5.5T are different. Higher topspeed than any 1/10 scale and about the same than a good (not top) 1/8. Lap time is just 0.2 sec slower than the fastest electric lap ever done by current WC Andy Moore during last euros at the same track. 4WD is slower on straight but has some advantage in corners.
I really donīt want that high rpm as I donīt believe bearings will work very long. Even good ones. Ceramic may be better here but will be damaged in an impact.
Next thing is the so small pinions you need for that high rpm donīt run that good and may result in higher drag. I think our motors have less rpm/more torque so we can run higher gearing.
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Old 06-09-2007, 09:49 AM   #1429
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V12, have you tested any of the Feiago based motors (GM, Orion, SpeedPassion) or maybe the new LRP motors, and how they compare to their Novak counterparts with equal winds?
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Old 06-09-2007, 11:13 AM   #1430
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We tested Nick's Insane speed run car today. We did some preliminary test on Radio range, traction and steerabilty through our 330 yard, mostly straight Course. No speed data yet. Here is what we found. Both of our Radios had insufficient range. I am using an Airtronics M8 with spectrum Pro receiver. Range, about 130 yards. Nick is using an FM set. range about 88 yards. I can possibly improve mine with the old reciever which has a longer antenna that I can run up through the body.
I did run my pan and easily got it up to full speed just past our Makeshift drivers stand in standard racing trim. I could steer it through the course at good speed. I had good traction. I had no tendency to lift the nose; the course was smooth.

I was able to drive Nicks car while he shot some video of the car doing some fairly slow speed work. It handled well. I thought it had good traction with the big drag racing rear foams, Nick did not. We used "Jack the Gripper". We ran it without body and wing though, so there might be improvements to be had later as well as secret work that has not been divulged. We also ran the car with only an 8s LiPo. It is set up for 12s Lipo.

We had some problems setting up the radio to work with the aircraft type Castle Creations Speed Control. The neutral was offset into forward throttle a bit. This made it a handful to stop and start. The big motor was very smooth, though. I had no trouble driving the car. An exciting morning.

Major Sponsors are Castle Creations and ThuderPower Batteries
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Attached Thumbnails
Pantoura, 1/10 Pan Car, 2S LiPo, Brushless, Tips and Tricks.-nicks-insane-speed-run-car.jpg  

Last edited by John Stranahan; 06-10-2007 at 03:40 PM.
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Old 06-09-2007, 01:14 PM   #1431
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Quote:
Originally Posted by John Stranahan View Post
We tested Nick's Insane speed run car today. We did some preliminary test on Radio range, traction and steerabilty through our 330 yard, mostly straight Course. No speed data yet. Here is what we found. Both of our Radios had insufficient range. I am using an Airtronics M8 with spectrum Pro receiver. Range, about 130 yards. Nick is using an FM set. range about 88 yards. I can possibly improve mine with the old reciever which has a longer antenna that I can run up through the body.
I did run my pan and easily got it up to full speed just past our Makeshift drivers stand in standard racing trim. I could steer it through the course at good speed. I had good traction. I had no tendency to lift the nose; the course was smooth.

I was able to drive Nicks car while he shot some video of the car doing some fairly slow speed work. It handled well. I thought it had good traction with the big drag racing rear foams, Nick did not. We used "Jack the Gripper". We ran it without body and wing though, so there might be improvements to be had later as well as secret work that has not been divulged. We also ran the car with only an 8s LiPo. It is set up for 12s Lipo.

We had some problems setting up the radio to work with the aircraft type Castle Creations Speed Control. The neutral was offset into forward throttle a bit. This made it a handful to stop and start. The big motor was very smooth, though. I had no trouble driving the car. An exciting morning.
John
Thanks for posting some info, John. Here is the video that I shot, more pics and more info:

http://fastrc.blogspot.com/2007/06/v...run-of-x2.html
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Old 06-09-2007, 02:45 PM   #1432
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I have to say we only run GM motors some other drivers are running LRP X-11 motors also but I think you will find very few Novak here. These are just more expensive than the others here and hard to find. Also I donīt see what advantage a Novak motor could have. Powerwise I just want commenting my friends motor as he had 2 days of testing and he was faster than anything else on the track (topspeed and laptime). This was a 5.5T as said before but we were trying different rotor and bearings. For some reason I didnīt have any practice before the race also just had 2 runs that day. My choice of pinions was very limited so couldnīt run the right gearing but motor was pretty fast also. From the specs and from the impression on the track it seems to me the GM motors do have more torque and less revs than others. For same speed you have to run higher gearing but it seems the motors can handle any gearing you throw at them, limit is just runtime and temperature. Regarding temperature the GM and Speedpassion do have an advantage here anyway because of the cooling vents and internal fan. This does really work, downside is just motor makes weird noise because of the internal fan. In the beginning I thought the GM and Speedpassion motors are the same but this seems just for the can/setup. Armature is different, maybe windings also. Regarding ESC we used Genius 95 sensorless (latest batch, just released) and TC Spec sensored and both worked very good with the GM motors. Batteries were IB4200 and GP4600.
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Old 06-09-2007, 02:57 PM   #1433
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Just remember a 2nd advantage with the GM or Speed Passion motors after reading in an other thread. Motor can at both motors is full metall even at the rear part so there is nothing what can deform when getting hot or bearing failure.
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Old 06-10-2007, 12:47 PM   #1434
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Slightly off topic but sort of related anyway.

I've had one of the Mcallister Nissans floating around for a while and I finally got around to painting it. I noticed on the one you painted that you cut out the piece in front of the rear spoiler. Wouldn't leaving that in there give you a bit more rear grip? I'll be running mine on carpet and I'm undecided on whether to cut it out or not. Did you try running the car with and without the cut out? Just curious as to whether I should cut mine out or not.
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Old 06-10-2007, 01:18 PM   #1435
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the rear cutouts will do one of two things depending on the design.

With the old Nissan bodies, it seems to lessen the rear downforce - while I was still using that body, I would cut 2-3 holes on either side to "tune" the amount of downforce at the rear.

However, with the Protoform Peugot, cutting those out actually increases rear downforce since it creates some additional airflow lower on the body which increases the effectiveness of the rear spoiler (essentially making it a wing rather than just a spoiler)

We actually discussed this a few pages ago. . .
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Old 06-10-2007, 03:21 PM   #1436
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Greasemonkey-That McAllister Nissan Has a huge cutout under the wing. I used the photo at MacAllister as a guide to cut the body. The wing is quite a bit farther back than most of the bodies so it requires less wing. I ran the chassis with both an Associated Nissan with no cutout (there are none marked on the body) and a large 2" spoiler chord and then the McAllister Nissan with no spoiler and the big cutout. The understeer/oversteer balance was almost the same. I think the intent of McAllister is to remove the entire cutout to look more like the fullsize race car with the integrated wing. I did not experiment without the cutout as I wanted that scale appearance on the McAllister Nissan.

The Toyota GT1 Body from Hotbodies and the Peugeot 905B Bodies have smaller cutouts that work like Boomer explained. They draw the airflow over the cab back down so that it contacts the wing better increasing rear downforce. I have not really experimented here though. I just cut them out and take peoples word for it.

I don't remove the front fender cutouts any more. It makes the front of the body too weak. Even if you just drill 1/4 inch holes.

Left pic shows the big cutout on the McAllister Nissan. Right pic shows the smaller cutouts on the Toyota GT1.

Speaking of Bodies Take a look at this Carbon Fiber Body and 7 mm Balsa core Carbon fiber Chassis. This is another entry in the high speed run.

Attached Thumbnails
Pantoura, 1/10 Pan Car, 2S LiPo, Brushless, Tips and Tricks.-mcallister-nissan-npt-90-resized.jpg   Pantoura, 1/10 Pan Car, 2S LiPo, Brushless, Tips and Tricks.-toyota-gt1-body-cutouts-001-resized.jpg  

Last edited by John Stranahan; 06-10-2007 at 09:22 PM.
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Old 06-11-2007, 08:50 AM   #1437
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the guy that wins the speed chalenge will be the guy that doesn't run out of track or wreck.. they use gyros in them?
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Old 06-12-2007, 12:32 AM   #1438
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RC18T pinions-I would have to think that these pinions are a different pitch although it is never stated just by looking at the pictures and spacing of the teeth. Drilling and reaming a brass pinion would be an easy task. A drilled hole will always come out slightly oversize on the diameter. The procedure would be to drill undersize and then ream the last .002 inch or so. Drilling and reaming a hardened steel pinion is another matter. The pinion should be as hard as the drill bit. There are carbide drills available as well as Cobalt steel bits. I imagine a carbide reamer would be expensive and very fragile. I have looked at those pinions. The first step would be what is the pitch. Somebody with one of those cars could try and mesh a 48 pitch spur with their spur to tell or I might order a spur one day.

If a hardened steel nickel plated gear (nickel is quite hard) goes 2 runs then a brass gear might last 5 laps. The Titanium nitride coated gold pinions go 20 runs in 12 tooth. The higher teeth numbers last much longer as there is little rubbing of teeth with the proper involute gear form. This form must be unatainable in the 12 tooth.

When I raced slot cars, I think we used 48 pitch gears and as low as 9 tooth pinions on a 1/16 inch motor shaft. It looked like a little paddle wheel. If you drill one of these out to 1/8 inch the teeth would just fall off as there is not enough metal below the root of the pinion teeth. I could grind an armature shaft down to 1/16 inch. I can actually do this on my lathe, but I think there will be too much flex when I am finished. There is already too much flex to brake with 64 pitch gears with a 1/8 shaft. Thanks for the gear input. I have thought about these things. I do have 10 gold 12 tooth pinions in hand. These should go at least a year. Stormer shows 6 in stock so maybe they have a nice box of 100 there.

Mike-Thanks for the extra detail on the bearings. Now tell me about this flame method. I'll tell you ahead of time if you get up to soldering temperatures which is well below red hot the part will anneal and go soft.

Syndrome-The search within threads is still there, you just have to scroll to the bottom of the new page that pops up for the input window. I had the same trouble.

I also had trouble with the editor. I had to go back into settings and change from Wysiwyg back to normal editing to fix the problem.

Inspgadgt- If you compare my present gearing to my former gearing with stock pan cars you will find I use lower ratios. This is mostly for performace but it has the benefit of lower temps. Temps are still high. I am running hot mods. 3.5 and 4.5 turn are hot mods. The car has more rear traction with the 3 link. Instead of spinning the back tire the lower gears now create weight transfer and more forward traction. I am satisfied that my Mamba problems are a sensorless problem that shows its ugly head under difficult driving conditions, Low traction, delicate cornering, starting from a stop. In some classes of racing these problems may not appear.
I have the GTB in the car now. It is so damn smooth on the bench. It is like a night and day difference. The brakes are also very smooth. The Novak rep is looking into trading my Mamba plus some cash for a GTB system.

Eric-Thanks for the note on the tires. I made the correction once my editor got fixed up.

I.R.S. Pivot Ball Installation Tool
I got this tool in and just tried it. Removing and installing the ball is now a low force operation. Now the good part. I had a couple of balls that were tight in the socket. If you take and insert the ball and then snug the tool and take another 1/3 turn tight, you very uniformly increase the socket size without leaving any burrs to create friction. If it is still tight you go just a fraction more on the tightening than you did before until it fits with no play. That part was super nice and hard to obtain with the method I used previously.
The RC4less pivot balls fit the kinpin and socket nicely.
The RC18T pinions are .5 module pitch. They are not quite standard 48 pitch.

http://www.engineersedge.com/gear_pitch_chart.htm
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Old 06-12-2007, 10:31 AM   #1439
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That Carbon Fiber Speedrun car does use a gyro. He makes parts for Helicopters so its handy for him. It was added later in development to increase straight line stability. There is considerable tire spin during his run. Even at high speed on his home course. This caused a 20-30% error in top speed by the onboard speed aquisition device. This was checked by radar.

Sydewynder-Thanks for the Engineering data. I think pitch is the number of teeth of a given size that are placed on a 1 inch diameter gear. I'll have to read up on what .5 module actually means. It is close to 50 pitch from the chart you linked to and would rule out that gear.
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Old 06-12-2007, 11:04 AM   #1440
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i remember reading an article years ago about 48p gears. i don't recall who wrote it, either someone at Robinson or at AE, but they said that 17t is the smallest you can go and have the gear truly be 48p. perhaps that's why you are wearing out gears when you go smaller?
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