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

Tamiya mini cooper

Like Tree288Likes

Tamiya mini cooper

Old 12-19-2008, 12:30 PM
  #7906  
R/C Tech Elite Member
iTrader: (10)
 
monkeyracing's Avatar
 
Join Date: Mar 2008
Location: Calgary, AB
Posts: 6,305
Trader Rating: 10 (100%+)
Default

Today's questions are about diffs and servos...

Balll diff I've got a ball diff I use in my mini. It's kept clean and well lubed, but it's kinda crunchy. Any ideas as to why that might be? Maybe because it's tightened down quite a bit?

Gear diff I've heard of people shimming the gear diff for a mini. Any ideas as to what size of shim to use and where I might find some?

Essentially, I'd like to have smooth, predictable diff action, with a decent degree of lock up. Are those two thing mutually exclusive in minis?

Steering servo I read something this morning about someone using a mini servo in an M-03. I've tried this, but the servo is too small to reach between the two mounting points. Any ideas how I might accomplish this one? I thought about just building an adaptor of some kind, but haven't actually tried it yet.

Any ideas you guys have would be appreciated.

Thanks!
monkeyracing is offline  
Old 12-19-2008, 02:28 PM
  #7907  
Tech Elite
iTrader: (38)
 
caltek1's Avatar
 
Join Date: Mar 2007
Posts: 3,422
Trader Rating: 38 (100%+)
Default

monkeyracing,

Ball Diff: I build as per instructions and use lots of tamiya anti wear grease, this will make the diff very smooth. As Defmondo pointed out, do not over tighten otherwise you will strip the diff. Some people also insert an extra cone washer to make it a little tighter, however that may go against your TCS rules.

Gear Diff: Add thicker washers to each side of the diff, or if you have extras add a second washer to each side. The costly way to make the action stiffer is to pack with tamiya anti wear grease, however this loosens up after a short time. Just use the kit supplied as a guide for size. Whem you get new bevel gears for the diff, normally has replacement washers with it.

SERVO SAVER: I have recently fitted the Tamiya M-Chassis Aluminum Horn and Hi Torque servo saver to my Mini and it works great. It is the same as the kit supplied plastic horn in alloy and uses the Hi torque servo parts and springs. This will give the same throw as the original, but is now stronger.

When you use smaller servo's and servo savers you end up affecting your steering on the car. I use a full size digital servo. I have found that the plastic servo posts are better replaced with alloy posts. This limits the amount of flex when turning the steering lock to lock. Some also have four mounting screws for the servo, which gives more rigidity to the assembly.

Just my thoughts.

Calvin.
caltek1 is offline  
Old 12-19-2008, 04:34 PM
  #7908  
Tech Master
iTrader: (8)
 
KREATOR1's Avatar
 
Join Date: Sep 2003
Location: Malaysia
Posts: 1,728
Trader Rating: 8 (100%+)
Default

Any of you guys tried larger pinion than 20t with the sportune black can motor?
KREATOR1 is offline  
Old 12-19-2008, 05:56 PM
  #7909  
Tech Elite
iTrader: (38)
 
caltek1's Avatar
 
Join Date: Mar 2007
Posts: 3,422
Trader Rating: 38 (100%+)
Default

KREATOR1,

You can fit a 21 tooth in without doing anything to the chassis, just bolt in the normal position for 20 tooth. Larger can be fitted, however you can only put one screw in to hold the motor.You would also need to use a spacer so that you do not strip the spur gear.

I have never tried this myself, but have seen it used. Was fast in a straight line, but couldn't corner due to excessive speed.

However this goes against the spirit of mini racing. Personnally I think its waste of time, but each to there own.

Regards,

Calvin
caltek1 is offline  
Old 12-19-2008, 06:47 PM
  #7910  
Tech Master
iTrader: (23)
 
edwintklee's Avatar
 
Join Date: Jun 2005
Location: wonderfull place called, MALAYSIA.
Posts: 1,592
Trader Rating: 23 (96%+)
Default

Originally Posted by caltek1
KREATOR1,

You can fit a 21 tooth in without doing anything to the chassis, just bolt in the normal position for 20 tooth. Larger can be fitted, however you can only put one screw in to hold the motor.You would also need to use a spacer so that you do not strip the spur gear.

I have never tried this myself, but have seen it used. Was fast in a straight line, but couldn't corner due to excessive speed.

However this goes against the spirit of mini racing. Personnally I think its waste of time, but each to there own.

Regards,

Calvin
fot your info, i have got to know some are runing with 23t pinion...
edwintklee is offline  
Old 12-19-2008, 07:10 PM
  #7911  
R/C Tech Elite Member
iTrader: (10)
 
monkeyracing's Avatar
 
Join Date: Mar 2008
Location: Calgary, AB
Posts: 6,305
Trader Rating: 10 (100%+)
Default

Originally Posted by caltek1
SERVO SAVER
Nah, not concerned about the servo saver. I use Kimbrough large and extra large. Gotta love those things.

My concern is about how to line up the mounts on a mini servo with the mounting points on an M03 chassis. I hear of people using smaller servos, but haven't found any pictures or instructions on how they did it.

I'm thinking that gluing a couple of servo posts together (side/side) would add the extra bit of reach I need to make it happen.

Jim
monkeyracing is offline  
Old 12-19-2008, 07:10 PM
  #7912  
Tech Master
iTrader: (8)
 
KREATOR1's Avatar
 
Join Date: Sep 2003
Location: Malaysia
Posts: 1,728
Trader Rating: 8 (100%+)
Default

calvin,

I did strip my spur gear using 22t pinion and fry the black can motor
on my last race.
Now i got my fresh set of gear and chassis and not planing to do the mod anymore. But if you guys got to know how to modify the motor holes. plz share with me.
KREATOR1 is offline  
Old 12-19-2008, 08:30 PM
  #7913  
Tech Elite
iTrader: (38)
 
caltek1's Avatar
 
Join Date: Mar 2007
Posts: 3,422
Trader Rating: 38 (100%+)
Default

KREATOR1,

I have seen a 25 tooth pinion fitted into a mini. You only use one motor screw. The motor will need to be offset within the housing, meshed with the spur gear and then you place a wedge into the side of the motor, so that it can not move if you hit something. The other option is to drill out the motor screw holes and use a washer.

As I said, I have only seen it, never tried it.

Regards,

Calvin.

Last edited by caltek1; 12-19-2008 at 10:41 PM. Reason: grammer
caltek1 is offline  
Old 12-19-2008, 08:37 PM
  #7914  
Tech Elite
iTrader: (38)
 
caltek1's Avatar
 
Join Date: Mar 2007
Posts: 3,422
Trader Rating: 38 (100%+)
Default

monkeyracing,

I use the Kimbrough large servo saver on one of my mini's but I will be changing over to the new M chassis servo saver.

I have included a photo of it fitted to my mini. You need to use the Hi torque servo saver parts as well as the new horn.

regards,

Calvin.
Attached Thumbnails Tamiya mini cooper-dsc01498.jpg   Tamiya mini cooper-dsc01499.jpg  
caltek1 is offline  
Old 12-19-2008, 10:21 PM
  #7915  
Tech Fanatic
iTrader: (12)
 
xrayroooahhhh's Avatar
 
Join Date: Nov 2006
Location: CALGARY
Posts: 792
Trader Rating: 12 (100%+)
Default

Jim.....

Stop by the table and I'll show you the shimmed gear diff!!!! You can pretty much dial in whatever feel you want......if you know where/what to shim!!!

Big charity race tommorow.....I have to remember my camera.....

CU later,
R

Originally Posted by monkeyracing
Today's questions are about diffs and servos...

Balll diff I've got a ball diff I use in my mini. It's kept clean and well lubed, but it's kinda crunchy. Any ideas as to why that might be? Maybe because it's tightened down quite a bit?

Gear diff I've heard of people shimming the gear diff for a mini. Any ideas as to what size of shim to use and where I might find some?

Essentially, I'd like to have smooth, predictable diff action, with a decent degree of lock up. Are those two thing mutually exclusive in minis?

Steering servo I read something this morning about someone using a mini servo in an M-03. I've tried this, but the servo is too small to reach between the two mounting points. Any ideas how I might accomplish this one? I thought about just building an adaptor of some kind, but haven't actually tried it yet.

Any ideas you guys have would be appreciated.

Thanks!
xrayroooahhhh is offline  
Old 12-19-2008, 11:47 PM
  #7916  
R/C Tech Elite Member
iTrader: (10)
 
monkeyracing's Avatar
 
Join Date: Mar 2008
Location: Calgary, AB
Posts: 6,305
Trader Rating: 10 (100%+)
Default

Originally Posted by caltek1
monkeyracing,

I use the Kimbrough large servo saver on one of my mini's but I will be changing over to the new M chassis servo saver.

I have included a photo of it fitted to my mini. You need to use the Hi torque servo saver parts as well as the new horn.

regards,

Calvin.
Again, I'm not concerned about the servo saver. I've got that part nailed. No problems at all.

My question is in regards to fitting a mini servo (not the saver, just the servo) to the M-03 chassis.

For example: I have a regular sized servo on the car now. I want to fit a HiTec 225mg, which is a mini servo to the car.

Can you offer any advice on that?
monkeyracing is offline  
Old 12-19-2008, 11:54 PM
  #7917  
Tech Fanatic
iTrader: (34)
 
SchuMi2's Avatar
 
Join Date: Nov 2003
Posts: 951
Trader Rating: 34 (100%+)
Default

Originally Posted by monkeyracing
Nah, not concerned about the servo saver. I use Kimbrough large and extra large. Gotta love those things.

My concern is about how to line up the mounts on a mini servo with the mounting points on an M03 chassis. I hear of people using smaller servos, but haven't found any pictures or instructions on how they did it.

I'm thinking that gluing a couple of servo posts together (side/side) would add the extra bit of reach I need to make it happen.

Jim
Jim

You can run a piece of carbonfiber 3/8' wide from original servo mounting holes on the chassis and drill 2 holes in the required position for the mini servo. This should work fine. You will need to shim between the carbon plate and chassis and also use servo mounts that sit flush with the bottom of the servo. Shimmed up correctly and it will sit at the same position as a std servo. You can also lower it a little if you want.
SchuMi2 is offline  
Old 12-20-2008, 01:27 AM
  #7918  
Tech Elite
iTrader: (38)
 
caltek1's Avatar
 
Join Date: Mar 2007
Posts: 3,422
Trader Rating: 38 (100%+)
Default

Jim,

Not sure why you want to run mini servo. I have seen a few of the standard servo's broken when hit by another mini. I would think these would not be as strong.

I did understand your question, just wanted to show the new mini aluminum servo saver fitted to a mini.

Sorry I have never seen a Mini here in aust fitted with a mini servo. it wouldn't meet our mini rules, built as per instructions.

regards,

Calvin
caltek1 is offline  
Old 12-20-2008, 01:52 AM
  #7919  
Tech Addict
iTrader: (2)
 
Join Date: Jun 2008
Posts: 538
Trader Rating: 2 (100%+)
Default

Originally Posted by caltek1
monkeyracing,

I use the Kimbrough large servo saver on one of my mini's but I will be changing over to the new M chassis servo saver.

I have included a photo of it fitted to my mini. You need to use the Hi torque servo saver parts as well as the new horn.

regards,

Calvin.
I've heard that the Hi torque saver doesn't last as long as the Kimbrough, any inputs on this?

The blue aluminium saver looks really cool though!
stocker is offline  
Old 12-20-2008, 01:56 AM
  #7920  
Tech Champion
iTrader: (35)
 
cannon's Avatar
 
Join Date: Sep 2003
Location: A total distraction
Posts: 7,266
Trader Rating: 35 (100%+)
Default

The blue alloy horn replaces the part of the hi torque servo saver that wears out. And is the correct length for the Mini
cannon is offline  

Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service -

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.