Go Back  R/C Tech Forums > General Forums > Electric On-Road
Tamiya F104 Pro! >

Tamiya F104 Pro!

Like Tree12Likes

Tamiya F104 Pro!

Old 12-08-2010, 04:23 AM
  #3961  
Tech Elite
iTrader: (32)
 
Arahawak's Avatar
 
Join Date: May 2006
Location: A.D. 2030
Posts: 3,447
Trader Rating: 32 (100%+)
Default

Originally Posted by gashuffer View Post
Adding shims under the ball connector where the arms snap into on the topdeck will increase static castor. This will raise the rear of the arm by how many mm shims you use.

Please excuse my dirty car
Thank you very much, just needed some visual confirmation.

So adding to the rear for more static castor and add the front for??
What does it do to the car?? sorry am not really understanding the previous posting...
Arahawak is offline  
Old 12-08-2010, 04:32 AM
  #3962  
Tech Master
iTrader: (40)
 
iknowjoe's Avatar
 
Join Date: Dec 2008
Location: Edison, NJ, USA
Posts: 1,134
Trader Rating: 40 (100%+)
Default

Originally Posted by gashuffer View Post
Please excuse my dirty car
You know we have an air compressor at the track right?
I know... we got out way too late the other night and cleaning the car was not a priority. Gettin home was.
See you Sat. F1 Nation baby! Hell Yeah!
iknowjoe is offline  
Old 12-08-2010, 06:25 AM
  #3963  
Tech Champion
iTrader: (28)
 
MantisWorx's Avatar
 
Join Date: Jun 2010
Posts: 5,955
Trader Rating: 28 (97%+)
Default

Originally Posted by Arahawak View Post
Thank you very much, just needed some visual confirmation.

So adding to the rear for more static castor and add the front for??
What does it do to the car?? sorry am not really understanding the previous posting...

if you shim the rear you will go from a negative castor number to a more positive number ie -4 castor to -3 castor which will give you more turn in, less high speed steering. shimming the front will do the opposite. BUT since the arm is in a fixed state you cannot shim too much or the arm will bind (i dont know what the limits are though). the thing is though by using the Tamiya style of camber adjustments when you add more negative camber you also decrease the castor too (see the sketch i posted earlier) so if you want to counter act what the camber adjustment does than you should shim the front to attempt to get the castor back to where it was.
MantisWorx is offline  
Old 12-08-2010, 06:50 AM
  #3964  
Tech Champion
iTrader: (28)
 
MantisWorx's Avatar
 
Join Date: Jun 2010
Posts: 5,955
Trader Rating: 28 (97%+)
Default

ok through the wonders of autocad i have drawn out exactly what will happen if you add rear shims to the arms! as the suspension is compressed you will lose static negative camber and i think we all agree with that but what may surprise you is that according to my sketch raising the rear shims by 4mm only gives you .006" of a decrease(with 2mm of arm travel) which is not very much at all (avg human hair is about .007") . now according to Robk doing this will increase mid corning and that is true but now this is got me thinking. my main issue with the 104 frame chassis is just not enough steering in general on asphalt, i just cant seem to get enough high speed steering with the available tire at all. this weekend im going to experiement with this and see what i can come up with on the mantisworx front i can set my static castor to where i get enough turn in and then shim the front so maybe i can get more high speed steering. in theory it should work but i dont know if i can get enough shim under the front to make it effective.
Attached Thumbnails Tamiya F104 Pro!-tamshim.jpg  
MantisWorx is offline  
Old 12-08-2010, 07:05 AM
  #3965  
Tech Champion
iTrader: (28)
 
MantisWorx's Avatar
 
Join Date: Jun 2010
Posts: 5,955
Trader Rating: 28 (97%+)
Default

while we are on the subject of front ends anyone want to explain how the new generation of 1:1 F1 is calculated? you cant apply the normal roll center rules to them because the arms never cross paths! i made a model with "high center" and it is very aggressive as far as what it does when weight transfers. i think that because the chassis is so long you dont get as much "roll" therefore the geometry has to be very aggressive to keep the tires flat. anyone have any insight or links that explain?
MantisWorx is offline  
Old 12-08-2010, 07:54 AM
  #3966  
Tech Elite
iTrader: (32)
 
Arahawak's Avatar
 
Join Date: May 2006
Location: A.D. 2030
Posts: 3,447
Trader Rating: 32 (100%+)
Default

Originally Posted by MantisWorx View Post
if you shim the rear you will go from a negative castor number to a more positive number ie -4 castor to -3 castor which will give you more turn in, less high speed steering. shimming the front will do the opposite. BUT since the arm is in a fixed state you cannot shim too much or the arm will bind (i dont know what the limits are though). the thing is though by using the Tamiya style of camber adjustments when you add more negative camber you also decrease the castor too (see the sketch i posted earlier) so if you want to counter act what the camber adjustment does than you should shim the front to attempt to get the castor back to where it was.
hmmz.. ok thanks for the info.

so in layman terms, shim the rear for technical tracks and shim the front for high speed flowing track?
Arahawak is offline  
Old 12-08-2010, 08:06 AM
  #3967  
Tech Champion
iTrader: (22)
 
robk's Avatar
 
Join Date: Aug 2001
Location: Macho Business Donkey Wrestler
Posts: 8,045
Trader Rating: 22 (100%+)
Default

Originally Posted by MantisWorx View Post
ok through the wonders of autocad i have drawn out exactly what will happen if you add rear shims to the arms! as the suspension is compressed you will lose static negative camber and i think we all agree with that but what may surprise you is that according to my sketch raising the rear shims by 4mm only gives you .006" of a decrease(with 2mm of arm travel) which is not very much at all (avg human hair is about .007") . now according to Robk doing this will increase mid corning and that is true but now this is got me thinking. my main issue with the 104 frame chassis is just not enough steering in general on asphalt, i just cant seem to get enough high speed steering with the available tire at all. this weekend im going to experiement with this and see what i can come up with on the mantisworx front i can set my static castor to where i get enough turn in and then shim the front so maybe i can get more high speed steering. in theory it should work but i dont know if i can get enough shim under the front to make it effective.
Please just shim the car and try it. It is visible to the naked eye when you work the suspension.
robk is offline  
Old 12-08-2010, 08:25 AM
  #3968  
Tech Champion
iTrader: (48)
 
gashuffer's Avatar
 
Join Date: Nov 2006
Location: RcVille
Posts: 5,230
Trader Rating: 48 (100%+)
Default

You are making this way more complicated than it is. We don't need cad, or a physics lesson. Just try it, if it works then run dat sh!t.
gashuffer is offline  
Old 12-08-2010, 08:36 AM
  #3969  
Tech Champion
iTrader: (28)
 
MantisWorx's Avatar
 
Join Date: Jun 2010
Posts: 5,955
Trader Rating: 28 (97%+)
Default

i agree with both of you????? i was just clarifying it for those who dont understand(arahawk). i did try it and it does work! there is no argument here at all GEEESH!
MantisWorx is offline  
Old 12-08-2010, 08:37 AM
  #3970  
Tech Champion
iTrader: (28)
 
MantisWorx's Avatar
 
Join Date: Jun 2010
Posts: 5,955
Trader Rating: 28 (97%+)
Default

Originally Posted by Arahawak View Post
hmmz.. ok thanks for the info.

so in layman terms, shim the rear for technical tracks and shim the front for high speed flowing track?
i would agree with that!
MantisWorx is offline  
Old 12-08-2010, 08:49 AM
  #3971  
Tech Champion
iTrader: (73)
 
MikeXray's Avatar
 
Join Date: Oct 2006
Location: New York
Posts: 5,755
Trader Rating: 73 (100%+)
Default

Originally Posted by MantisWorx View Post
i agree with both of you????? i was just clarifying it for those who dont understand(arahawk). i did try it and it does work! there is no argument here at all GEEESH!
I got no problems with the CAD images Its always good to back up the feel with the math.
MikeXray is offline  
Old 12-08-2010, 08:58 AM
  #3972  
Tech Champion
iTrader: (28)
 
MantisWorx's Avatar
 
Join Date: Jun 2010
Posts: 5,955
Trader Rating: 28 (97%+)
Default

thank you! it seems like i cant even agree without an argument busting out! i like to verify everything too!
MantisWorx is offline  
Old 12-08-2010, 11:44 AM
  #3973  
R/C Tech Elite Member
iTrader: (36)
 
abailey21's Avatar
 
Join Date: Aug 2007
Location: ATX
Posts: 5,310
Trader Rating: 36 (100%+)
Default

Anyone else ever have issue mounting Ride tires on stock Tamiya rims? (Rubbers)

Seems like the Ride tires are smaller than the Tam rims?
abailey21 is offline  
Old 12-08-2010, 12:38 PM
  #3974  
Tech Champion
iTrader: (28)
 
MantisWorx's Avatar
 
Join Date: Jun 2010
Posts: 5,955
Trader Rating: 28 (97%+)
Default

you have to use ride wheels with ride tires, i made the same mistake!
MantisWorx is offline  
Old 12-08-2010, 01:41 PM
  #3975  
Tech Champion
iTrader: (48)
 
gashuffer's Avatar
 
Join Date: Nov 2006
Location: RcVille
Posts: 5,230
Trader Rating: 48 (100%+)
Default

Originally Posted by MantisWorx View Post
thank you! it seems like i cant even agree without an argument busting out! i like to verify everything too!
I'm not arguing at all, but sometimes a picture(of the car) of what needs to be done says a thousand words. Thats all. Some people just need the visual.
gashuffer is offline  

Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information -

Copyright 2021 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.