R/C Tech Forums

Go Back   R/C Tech Forums > General Forums > Electric On-Road

Reply
 
Thread Tools Search this Thread
Old 04-01-2007, 01:58 PM   #1051
Tech Elite
 
Join Date: Aug 2002
Location: Houston, Texas
Posts: 3,777
Trader Rating: 27 (100%+)
Send a message via AIM to John Stranahan
Default

Thanks for the info on screws. I am not really shopping hard for any. I just posted the data so that you would not throw away those good steel alloy black oxide finish screws and replace them with something inferior.

Greasemonkey-I did not find a good pic of the Robertson head. Is it a square hole "Clutch" like they have been using on RV's for a coons age. I notice some of them also have a phillips cross in them for end user maintenance. I'll look at those Corrally screws. Chances are the price is not competitive with Mcmaster-Carr.


Tire Wear
Carrol Smith notes in "Tune to Win" that good tire wear looks like ripples lined up with the circumference. I believe I discussed this on a previous thread. I have noticed this wear on my rubber touring car tires when it is really hooked up on asphalt. Well my pan car was really hooked up the other day. I thought I would post a pic of the front tires as they show this same wear pattern. "Ripples lined up with the circumference" . This is most apparent after adding the traction compound in good sunlight.

When the tire is too soft you will notice rubber marbles on the surface as bits of the tread are tearing away. When it is too hard it will be scuffed completely smooth.

Note that I have exagerrated the pattern with photographic lighting tricks. It is just visible on the tire with the unaided eye.
John
Attached Thumbnails
Pantoura, 1/10 Pan Car, 2S LiPo, Brushless, Tips and Tricks.-foam-tire-wear-pattern.jpg  
John Stranahan is offline   Reply With Quote
Old 04-01-2007, 02:28 PM   #1052
Tech Lord
 
syndr0me's Avatar
 
Join Date: Dec 2004
Location: 5280 Raceway
Posts: 13,140
Trader Rating: 32 (100%+)
Default

Quote:
Originally Posted by John Stranahan
Something electronic gave up the ghost. In the last heat the car slowed to a stop twice and recovered after 3-5 or so excruciating seconds. It may be the motor bearing or the speed control.
John,

You probably figured this out by now, but I believe most ESC's have something called "locked rotor detection." If your bearing was going out, it may have triggered it.
syndr0me is offline   Reply With Quote
Old 04-01-2007, 04:34 PM   #1053
Tech Elite
 
Join Date: Aug 2002
Location: Houston, Texas
Posts: 3,777
Trader Rating: 27 (100%+)
Send a message via AIM to John Stranahan
Default

The bearing was only slightly gritty. Because the incidents happened on fairly high speed sections of the track, I don't think it could have triggered a locked rotor sequence. I could still squirt the car around in a little circle, It just did not have good power. I have replaced the bearing. I await good track conditions for a full pack test. It was a bit wet today.
John
John Stranahan is offline   Reply With Quote
Old 04-01-2007, 09:01 PM   #1054
Tech Addict
 
GreaseMonkey's Avatar
 
Join Date: Apr 2006
Location: Ottawa, Canada
Posts: 552
Trader Rating: 4 (100%+)
Default

I have no contact with RV's so I couldn't tell you but it is a square head with a slight taper. Up until I moved to Canada I had never seen them but they are used here for building houses and such. I've never seen them with a cross before though. It may be possible that you've seen pozidriv which is similar to a phillips drive but with a smaller cross in the 45 degree. The only place I know of them being used is on older British cars.
__________________
I'm not a grown man playing with toys. I'm a hobbyist.
GreaseMonkey is offline   Reply With Quote
Old 04-03-2007, 02:36 PM   #1055
Tech Elite
 
Join Date: Aug 2002
Location: Houston, Texas
Posts: 3,777
Trader Rating: 27 (100%+)
Send a message via AIM to John Stranahan
Default

Grease Monkey that is just what a Clutch tip looks like. I get the tips when I buy one of those multitip sets.

Novak Endbell Bearing

I have a second report of a bearing failure on a Novak 3.5. Not too old. I will have to conclued that the RPM is killing the bearing after some use as the bearings on the 4.5 and 5.5 lasts longer. Anyway keep a couple of spares in the pit box if you run this motor. Here is my response. I wonder if a dynamic balance by Novak on the sintered armatures would cure this.

Those are 3/16 by 1/2 inch. Avid RC has them for a $1.00 I have not tried these from Avid yet. MurdochRC has them in ceramic for $10.00 They are just labeled BL bearing at Murdoch. These are as good as Novaks. Novak sells the endbell with bearing already pressed in and sealed with high temperature sealant for about $23.00

Hammer the bearing out with a punch.
I use high temperature Loctite on mine and hammer the bearing in with a plastic block on the bearing. Not too difficult.


Pic is the front suspension mounting block for the new Mini-T front suspension that is going on the second wide prototype. Well you have too use a lot of imagination at this point. Left and right halves are being machined together.
John
Attached Thumbnails
Pantoura, 1/10 Pan Car, 2S LiPo, Brushless, Tips and Tricks.-front-suspension-upright.jpg  

Last edited by John Stranahan; 04-03-2007 at 10:57 PM.
John Stranahan is offline   Reply With Quote
Old 04-03-2007, 10:50 PM   #1056
Tech Elite
 
Join Date: Aug 2002
Location: Houston, Texas
Posts: 3,777
Trader Rating: 27 (100%+)
Send a message via AIM to John Stranahan
Default

Suspension Arm Mount
I made some progress on the Mini T front suspension mount for the second wide pan car prototype. I thought I would show a pic. Note that this is both the left side and right side mount that will be cut on the red lines. Yes that upper arm is supported only on one side to give that stiff upper arm some flex fore and aft. Some Delrin pivots will give additional flex for and aft in a crash. You are looking at the inboard side of the mount. The lower arms mount low and inboard, the shorter upper arms mount high and outboard. Narrow graphite shock towers will grow out of the heavy end of the mount, similar to my rear shock towers. Each mount will attach to the chassis with 3, 4-40 screws.
John
Attached Thumbnails
Pantoura, 1/10 Pan Car, 2S LiPo, Brushless, Tips and Tricks.-suspension-arm-mounts-001-cropped.jpg  
John Stranahan is offline   Reply With Quote
Old 04-04-2007, 03:23 AM   #1057
Tech Regular
 
Join Date: Jul 2004
Location: Kuala Lumpur Malaysia
Posts: 278
Default

john,

Why not you lubricate your bearing with bearing lube before every run. make sure also that you clean up the inside of the motor after about 10 battery packs.

I've been using my 3.5 inside my wide pan car for months. So far so good.
azmio is offline   Reply With Quote
Old 04-04-2007, 08:53 AM   #1058
Tech Elite
 
Join Date: Aug 2002
Location: Houston, Texas
Posts: 3,777
Trader Rating: 27 (100%+)
Send a message via AIM to John Stranahan
Default

azmio-I tried that. I was opening the motor on that schedule to oil the back bearing and clean up the front. The problem seems to be dirt entry. It is hard to get lube in without taking a little grit with it. The bearing that lasted the longest on my track was lubed with grease on a 4.5. I am trying grease now.

John
John Stranahan is offline   Reply With Quote
Old 04-04-2007, 04:41 PM   #1059
Tech Elite
 
Join Date: Aug 2002
Location: Houston, Texas
Posts: 3,777
Trader Rating: 27 (100%+)
Send a message via AIM to John Stranahan
Default

Losi Mini T based front suspension

Here is a pic that lets you view the scale of that aluminum suspension mount. The final suspension is going to look very nice. It has a low center of gravity. Low height, long arms for good traction on asphalt, Pivot pins outboard for good wear, vertical Delrin inner pivot pin mounts for good flex in the crashes (I still need to machine these. They will be located where the white foam tape is and secured to .20 square Aluminum bar). There are also stiffer blue Aluminum arms available for carpet. The chassis can be narrower at the front. These pieces may see production stay tuned. I expect total weight to be similar to an Associated front suspension. The one aluminum suspension mount weighs .2 ounces.

If you are always having to reset camber you will appreciate the shim adjustable camber on this front end. It is a little more trouble to set, but it should stay put until you decide to change it. That upper arm will contribute a lot to crashworthiness.
John
Attached Thumbnails
Pantoura, 1/10 Pan Car, 2S LiPo, Brushless, Tips and Tricks.-suspension-arm-mounts-004-cropped.jpg   Pantoura, 1/10 Pan Car, 2S LiPo, Brushless, Tips and Tricks.-suspension-arm-mount-chassiss-mockup-001-cropped.jpg  

Last edited by John Stranahan; 04-04-2007 at 05:02 PM.
John Stranahan is offline   Reply With Quote
Old 04-04-2007, 09:53 PM   #1060
Tech Regular
 
Join Date: Jul 2004
Location: Kuala Lumpur Malaysia
Posts: 278
Default

John

Try this, since you need only two holes to attach the motor to the mount, use shoe goo to close the other bolt holes that you are not using. This will prevent dirt from coming in.

Once you secure the weak spots of the motor, you can just lube the motor bearing from outside. In every 10 runs, open the can and use compress air to get rid of spilled lube oil.

It's good to put lube oil before every run because it will cool off the bearing at high speed.
azmio is offline   Reply With Quote
Old 04-04-2007, 10:33 PM   #1061
Tech Elite
 
Join Date: Aug 2002
Location: Houston, Texas
Posts: 3,777
Trader Rating: 27 (100%+)
Send a message via AIM to John Stranahan
Default

Azmio- The dirt enters through the race to seal gap on the outside of the motor. This is where you need to put the oil in. Inside the motor is quite clean except for the black oil that oozes out of the lubed bearing. The fact that the oil is black means you are making powder out of the bearings. The dirt goes in with the oil. I used a Q-tip to clean the area outside before oiling for one bearing. I used compressed air to clean the area for one bearing. Generally compressed air just drives dirt into hidden recesses like the bearing races. I proved this to myself with one bearing. I expect yours to go any minute now. Anyway I have tried oil several ways. I am back to lightweight synthetic grease. I'll replace this once in a while. I am able to drive the car several times a week so my wear is accelerated compared to most hobbyist.

New Baby Shock Tower
Here is a pic of the baby shock tower. I may change the contour slightly for appearance, but it looks like it is a go. This clears all of my GTP bodies. So how is this better than the previous front suspension. The wheel rim does not contact the shock so I get more steering throw which is occasionally needed (like the heavy pollen day). The heavily loaded lower arm outboard pivot is now a pin which should wear well. I have a slightly better shock angle which should give the shock more travel. It is going to look very nice with blue aluminum pieces. I'll have to test this to see if the great performance is still there. I don't see why it would not be.

Note that the reason I don't use the associated front suspension is it did not work well on our track at high speed. The car tended to fly. This was improved with some shocks. The 3.5 and 3-link made the car go faster still and the car started to fly again. (Reports and pics are in the thread.) The new suspension cured this and cornered better also.
John
Attached Thumbnails
Pantoura, 1/10 Pan Car, 2S LiPo, Brushless, Tips and Tricks.-baby-shock-tower-resized.jpg  

Last edited by John Stranahan; 04-04-2007 at 10:47 PM.
John Stranahan is offline   Reply With Quote
Old 04-05-2007, 09:38 AM   #1062
Tech Addict
 
Iceracer's Avatar
 
Join Date: Feb 2006
Location: Canada
Posts: 656
Trader Rating: 1 (100%+)
Default

I'd be tempted to switch to a sealed type bearing with the hopes that once its run for a while the seal drag would be negligible on overall performance.
Iceracer is offline   Reply With Quote
Old 04-05-2007, 12:51 PM   #1063
Moderator
 
Pro ten Holland's Avatar
 
Join Date: May 2003
Location: Druten/Holland (Europe)
Posts: 1,677
Trader Rating: 1 (100%+)
Default

Here are some pictures of the new german prototype Pro10 that competed in our club race last weekend. It's called the SpeedLine
It features a single pivot rear suspension, and a modified asso front end.

It went really well on saturday, but the guys testing it couldn't get it together on sunday.
They have some setup issues to iron out.

The first production runs are scheduled in a few weeks. The price hasn't been determined yet, but the owner emphasized it will be competitively priced.

I'll post more info when I hear more.
Attached Thumbnails
Pantoura, 1/10 Pan Car, 2S LiPo, Brushless, Tips and Tricks.-p1020540_2.jpg   Pantoura, 1/10 Pan Car, 2S LiPo, Brushless, Tips and Tricks.-p1020541_2.jpg   Pantoura, 1/10 Pan Car, 2S LiPo, Brushless, Tips and Tricks.-p1020542_2.jpg  
__________________
http://www.rc-lemans.de/
Pro ten Holland is offline   Reply With Quote
Old 04-05-2007, 02:56 PM   #1064
Tech Champion
 
Join Date: Nov 2001
Location: Hawaii, USA
Posts: 7,186
Default

Trinity used a front end just like that on one if their older 1/12th cars. Basically it's an AE lower arm connected by a graphite plate and EV10 upper links. I rather miss my old EV10...could put a couple back together if I had the right plastic parts. But the front end with upper links like that is a real pain to adjust. Mainly because both upper links adjust both caster and camber at the same time. So to adjust it easily you need an alignment tool that measures both camber and caster at the same time. I believe Race Tech had one specifically for the EV10 that clamped on to the lower suspension plate. Wouldn't work for this front end but something like that would make adjustment easier.
InspGadgt is offline   Reply With Quote
Old 04-05-2007, 08:10 PM   #1065
Tech Fanatic
 
Join Date: Jan 2004
Location: Colorado, Above The Rest
Posts: 992
Trader Rating: 2 (100%+)
Default

Quote:
Originally Posted by InspGadgt
Trinity used a front end just like that on one if their older 1/12th cars. Basically it's an AE lower arm connected by a graphite plate and EV10 upper links. I rather miss my old EV10...could put a couple back together if I had the right plastic parts.
As did Bud's Racing products, it was called the supermachine front end.
__________________
Team BSR
Team Power Push
Protoform Race Bodies
KSKT Racing - #1 in SK Racing Chassis
Darkside Motorsports - "WE ARE WHAT'S NEXT." - www.darksidems.com
THE DARKSIDE is offline   Reply With Quote
Reply

Similar Threads
Thread Thread Starter Forum Replies Last Post
Associated Factory Team TC5, Brushless, LiPo, Li-ion Nanophosphate, Tips and Tricks John Stranahan Electric On-Road 839 11-01-2011 04:31 PM
Xray T2R, 2100 mah 2c LiPo, and Mabuchi power: Tech tips and Tricks gacjr0 Electric On-Road 46 11-18-2007 10:09 AM
tips and tricks XXX-NT streetstock Electric Off-Road 2 05-13-2005 10:50 AM
Tips & Tricks Steevo Electric On-Road 54 08-08-2003 10:09 PM
Tips And Tricks rctc3 Electric On-Road 36 03-10-2002 10:54 AM



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are Off



All times are GMT -7. It is currently 05:21 PM.


We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
Powered By: vBulletin v3.9.2.1
Privacy Policy | Terms of Use | Advertise Content © 2001-2011 RCTech.net