R/C Tech Forums

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

Reply
 
Thread Tools Search this Thread
Old 02-20-2014, 03:22 PM   #946
Tech Regular
 
terryh's Avatar
 
Join Date: Nov 2005
Posts: 343
Default

Quote:
Originally Posted by Govert View Post
I do appreciate your comment, but it seems to be difficult to explain how ackermann can be adjusted on this car (absolutely no personal attack or something negative). Ackermann is a quite important setting, so I play with it a lot. Especially on my home track, I don't need that much ackermann. Less is more seems to be true.
I find it odd nobody seems to be using ackermann as a setup option (or knows how to adjust it). With all do respect, but just saying "just use 2mm" (because everybody does it) isn't the way to figure out how ackermann can be adjusted on THIS car. Every other car I had I had no problems with it, but here it seems to be a puzzle at this moment.

And I never copy a setup. Every track is different, temperature, tire choice, type of asphalt, motor, gearing, weight distribution etc etc. These are all variable circumstances that make me want to find my own setup. Always works best for me.

Absolutely no flaming here, I do appreciate everyone's input. Just an interesting case in my opinion.
If you read some of the setups on Petit, you will see that plenty have used Ackermann options in their setup. Professor has it right if you want to understand it, also ARC do various option parts that you can use to adjust Ackermann. I just happen to like the feel of the kit parts but with 2mm spacer.

HTH
terryh is offline   Reply With Quote
Old 02-20-2014, 06:51 PM   #947
Tech Master
 
trigger's Avatar
 
Join Date: Jun 2004
Location: SoCal
Posts: 1,032
Trader Rating: 6 (100%+)
Default

Ackerman is an important adjustment but it's a fine adjustment. I usually don't mess with Ackerman unless I'm totally dialed and looking for some refinement. But when adapting to different tracks, springs, oils, roll center, wheelbase are my main adjustments to get dialed in.

At this point, it's set it and forget it. Even if the Ackerman isn't in the most optimized positions for each track, I bet this cars will still make great/competitive lap times in capable hands.
__________________
Minh Nguyen
[Maclan Racing][Xpert]
trigger is offline   Reply With Quote
Old 02-20-2014, 07:48 PM   #948
Tech Elite
 
Join Date: Nov 2009
Location: Woodinville, WA
Posts: 2,512
Trader Rating: 8 (100%+)
Default

Quote:
Originally Posted by trigger View Post
I usually don't mess with Ackerman unless I'm totally dialed and looking for some refinement.
That's why I still only have a very theoretical understanding of Ackerman. I usually don't have my car at that level of dialed-ness.

-Mike
grippgoat is offline   Reply With Quote
Old 02-20-2014, 10:13 PM   #949
Tech Elite
 
Josh-n-ya's Avatar
 
Join Date: May 2011
Location: Alameda, CA
Posts: 2,027
Trader Rating: 72 (100%+)
Default

Quote:
Originally Posted by terryh View Post
@ Josh-n-ya

Hey Josh, sent you a pm re VTA racing, hoping you can help.

Or, anyone who has raced the R10 2013 in VTA with any setup knowledge for carpet, please feel free to offer any advise that you can.

Much appreciated

Terry
You have a pm. Hope that helps even though I haven't ran on carpet it should work too. Good luck, I know that my ARC vta has been unbeatable at a couple of tracks. Just make sure you have clean bearings and everything is smooth with no binding. That's the key to VTA.
Josh-n-ya is offline   Reply With Quote
Old 02-21-2014, 12:17 AM   #950
Tech Regular
 
terryh's Avatar
 
Join Date: Nov 2005
Posts: 343
Default

Quote:
Originally Posted by Josh-n-ya View Post
You have a pm. Hope that helps even though I haven't ran on carpet it should work too. Good luck, I know that my ARC vta has been unbeatable at a couple of tracks. Just make sure you have clean bearings and everything is smooth with no binding. That's the key to VTA.
Thanks for your help Josh
terryh is offline   Reply With Quote
Old 02-21-2014, 08:08 AM   #951
Tech Champion
 
Join Date: Sep 2001
Location: Mongville
Posts: 6,974
Trader Rating: 9 (100%+)
Default

For anyone not following the teams efforts at TITC, at the end of day 1 of qual, arc is tq in non boosted stock and 3 cars in the top 10 in boosted stock. Great work guys and good luck for the rest of the event.

The good news for the rest of us, there was some trialling of some new parts, although the standard release parts produced the best lap times.
__________________
12th Scale - The premier class (if you can make runtime)
Besercoe is offline   Reply With Quote
Old 02-21-2014, 05:52 PM   #952
Tech Regular
 
Join Date: Jul 2007
Location: The Netherlands
Posts: 264
Default

Quote:
Originally Posted by Professor View Post
i have always been of the belief the if you add spacers to the attatchment points of the bellcrank it reduces the ackerman & increases ackerman if you remove spacers , all the while remembering that this adjustment affects the slip angle of the front wheels
i only make changes to the ackerman in increments of .5 at at time as i find it does change the car a lot
there is a book "xxx main" or an app "rc set up workbench" which cover this in fairly good detail
Tried it, but adding spacers increased ackermann. Back to stock setting was better (less ackermann).

Quote:
Originally Posted by grippgoat View Post
I'm curious what your measurement technique is for determining whether it increases or decreases ackerman. And whether your definition of "increase" is more angle on the inside wheel vs. the outside, or more angle on the outside vs. the inside.

When thinking about ackerman, I usually just crank the steering to one side, and then look at it from the top and think "ok, if I added/removed a shim, that would push the tie rod this way, and that would do XXXX to the inside wheel and YYYY to the outside wheel".

-Mike
Ackermann increased: more angle on the inside wheel vs. outside wheel.
You can see it easily and you can measure it with a setup station and or a setup board with measuring points.

Quote:
Originally Posted by nikos2002 View Post
Here is some information I found from the ARC folks about Ackerman and measurement:

"you can use the setup station , TiTAN 30101-2009, then you can read the steering throw of each different ball crank , so you will have idea how it change and what different in your handling"

"Basically if you use shorter ball crank and less shim , you will have more ackerman angle, when you use longer bell crank and more shim(forward) , you will have less ackerman angle."

And to note that the bellcranks come in 18mm, 20mm and 22mm lengths.
I might give the 22mm a shot. But still a longer bell crank with more shims would be the same as 18mm with even more shims (same length all together as longer crank + shims).....Right? Confused...

Quote:
Originally Posted by terryh View Post
If you read some of the setups on Petit, you will see that plenty have used Ackermann options in their setup. Professor has it right if you want to understand it, also ARC do various option parts that you can use to adjust Ackermann. I just happen to like the feel of the kit parts but with 2mm spacer.

HTH
Yes, that might answer my earlier question: if I would try different bell cranks, would it change the ackermann setting? This might be the case I see.

Quote:
Originally Posted by trigger View Post
Ackerman is an important adjustment but it's a fine adjustment. I usually don't mess with Ackerman unless I'm totally dialed and looking for some refinement. But when adapting to different tracks, springs, oils, roll center, wheelbase are my main adjustments to get dialed in.

At this point, it's set it and forget it. Even if the Ackerman isn't in the most optimized positions for each track, I bet this cars will still make great/competitive lap times in capable hands.
I'm certainly not doubting the overall performance of the car, but fine tuning, in my opinion and experience, is desireable. Especially because I run boosted modified on a large and high speed track. (Excessively) rubbing tires are causing several problems, two of them are excessive tire wear and the rubbing actually slows cornering down in many cases.

Thanks for all your input guys, I might try different bell cranks, not sure yet.

Just to let you guys know, there is no problem with the car, love the car , but I would like to fine tune and understand the ackermann situation on the ARC.
__________________
www.rcpit.nl , RC dealer

www.machheemstede.nl
..................................Youtube: https://www.youtube.com/watch?v=_-Gkh2xZcQU
Modified 4 life
Govert is offline   Reply With Quote
Old 02-21-2014, 10:02 PM   #953
Tech Elite
 
Join Date: Nov 2009
Location: Woodinville, WA
Posts: 2,512
Trader Rating: 8 (100%+)
Default

Longer bellcranks would keep the inner balls more forward for a given amount of steering throw, so I'd expect it to be different to shorter cranks with more shims.

-Mike
grippgoat is offline   Reply With Quote
Old 02-21-2014, 10:54 PM   #954
Tech Master
 
trigger's Avatar
 
Join Date: Jun 2004
Location: SoCal
Posts: 1,032
Trader Rating: 6 (100%+)
Default

The 8.5mm plate adds even another factor into ackerman too. I chose to outfit my cars with 20mm bell cranks with 1mm shims and the 8.5 mm plate and have like the way the cars feels.
__________________
Minh Nguyen
[Maclan Racing][Xpert]
trigger is offline   Reply With Quote
Old 02-22-2014, 10:38 AM   #955
Tech Regular
 
Join Date: Jul 2007
Location: The Netherlands
Posts: 264
Default

Quote:
Originally Posted by grippgoat View Post
Longer bellcranks would keep the inner balls more forward for a given amount of steering throw, so I'd expect it to be different to shorter cranks with more shims.
You might be right. I will think about this.

Quote:
Originally Posted by trigger View Post
The 8.5mm plate adds even another factor into ackerman too. I chose to outfit my cars with 20mm bell cranks with 1mm shims and the 8.5 mm plate and have like the way the cars feels.
What is your experience with the 8.5mm plate? More or less ackermann? Or does something else changes?
__________________
www.rcpit.nl , RC dealer

www.machheemstede.nl
..................................Youtube: https://www.youtube.com/watch?v=_-Gkh2xZcQU
Modified 4 life
Govert is offline   Reply With Quote
Old 02-22-2014, 11:54 AM   #956
Tech Master
 
trigger's Avatar
 
Join Date: Jun 2004
Location: SoCal
Posts: 1,032
Trader Rating: 6 (100%+)
Default

I don't have a whole lot of Ackerman knowledge but when the 8.5 plate came out, I researched other chassis makes like the yokomo, tamiya and also X-ray and noticed that their steering plate positioned the ball studs quite close, I naturally figured it was the most optimized position and went that route.

The 22mm bell cranks were advertised to promote on power steering which I needed at the time but didn't like the idea of no shims could be used because of clearance with the fr suspension block. So I decided to meet in the middle and go with the 20mm to still allow some Ackerman adjustment flexibility.
__________________
Minh Nguyen
[Maclan Racing][Xpert]
trigger is offline   Reply With Quote
Old 02-22-2014, 09:11 PM   #957
Tech Master
 
Brokin Racing's Avatar
R/C Tech Elite Subscriber
 
Join Date: Nov 2008
Location: Sydney Australia
Posts: 1,252
Trader Rating: 68 (100%+)
Default

Quote:
Originally Posted by trigger View Post
I don't have a whole lot of Ackerman knowledge but when the 8.5 plate came out, I researched other chassis makes like the yokomo, tamiya and also X-ray and noticed that their steering plate positioned the ball studs quite close, I naturally figured it was the most optimized position and went that route.

The 22mm bell cranks were advertised to promote on power steering which I needed at the time but didn't like the idea of no shims could be used because of clearance with the fr suspension block. So I decided to meet in the middle and go with the 20mm to still allow some Ackerman adjustment flexibility.
I've done the same & am happy with the result.... great car!
__________________
Xray Since 2007 - LRP - PF - Futaba -
Brokin Racing is offline   Reply With Quote
Old 02-22-2014, 10:33 PM   #958
Tech Champion
 
Join Date: Sep 2001
Location: Mongville
Posts: 6,974
Trader Rating: 9 (100%+)
Default

Quote:
Originally Posted by Govert View Post
You might be right. I will think about this.



What is your experience with the 8.5mm plate? More or less ackermann? Or does something else changes?
The new plate seems to smooth out the steering arc, less initial bite with more mid corner bite. I wouldn't say it's perfect in all situations, but its worthy to have as an option.
__________________
12th Scale - The premier class (if you can make runtime)
Besercoe is offline   Reply With Quote
Old 02-23-2014, 01:49 AM   #959
Tech Master
 
Professor's Avatar
 
Join Date: Apr 2004
Location: Sydney,Australia
Posts: 1,064
Trader Rating: 10 (100%+)
Default

what is the 8.5 plate that is bieng refered to ???? can someone post a pic with this pate pls
__________________
VBC RACING AUS--HOBBYWING--MAD GRAPHICS--BITTY DESIGN
Professor is offline   Reply With Quote
Old 02-23-2014, 01:59 AM   #960
Tech Master
 
Professor's Avatar
 
Join Date: Apr 2004
Location: Sydney,Australia
Posts: 1,064
Trader Rating: 10 (100%+)
Default

opps no need for pic have it sorted, thanks
__________________
VBC RACING AUS--HOBBYWING--MAD GRAPHICS--BITTY DESIGN
Professor is offline   Reply With Quote
Reply


Tags
arc r10, rc-world, team titan


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 10:38 AM.


Powered By: vBulletin v3.9.2.1
Privacy Policy | Terms of Use | Advertise Content © 2001-2011 RCTech.net