Jump to content




Photo

How far will a chassis bow?


  • Please log in to reply
17 replies to this topic

#1 Tex

Tex

    Grand Champion Poster

  • Full Member
  • PipPipPipPipPipPipPipPip
  • 9,227 posts
  • Joined: 07-July 06
  • Gender:Male
  • Location:Denton, TX

Posted 27 November 2017 - 11:43 AM

Soooo, I was testing for an upcoming race(this past weekend, "Texas 2-Step" at Dallas Slot Cars).... my F-1 was working "OK" but not great. As the afternoon wore on and a number of offs accumulated, the handling deteriorated. A post-mortem revealed what you see in the pics. The marks on the lead shows where the arm shaft was hitting the lead as the chassis bowed under impact. Wow! That's at least a 1/8" bow of the chassis to do that! The impacts had also bent the main rails where they were soldered to the nose piece. Due to less-than-optimal construction techniques, the corrective action chosen was to grab the thing in both hands and bend it back. Qualified 9th(out of 15) and finished 4th overall(won the B-main).

Attached Images

  • Chassis Bow 5.jpg
  • Chassis Bow 3.jpg

Richard L. Hofer

Remember, two wrongs don't make a right... but three lefts do! Only you're a block over and a block behind.




#2 Uncle Fred

Uncle Fred

    Checkered Flag in Hand

  • Full Member
  • PipPipPipPipPipPip
  • 1,367 posts
  • Joined: 29-September 06
  • Gender:Male
  • Location:Northlake, TX

Posted 27 November 2017 - 12:00 PM

Rich, I've heard of a lot of excuses but this ones a real winner!  

 

Seriously, it looks like the shaft hit the lead 5 or 6 times..........  First of all I cant believe you ran into the wall that often nor that you hit once and the chassis flexed 5 or 6 times?   


Fred Correnti

#3 TG Racing

TG Racing

    On The Lead Lap

  • Full Member
  • PipPipPipPip
  • 468 posts
  • Joined: 11-December 11
  • Gender:Male
  • Location:Kettering, OH

Posted 27 November 2017 - 12:03 PM

Is your motor screwed or soldered in?  You might think about stripping it down and heat the chassis up on a flat plate to "relax" the rails.


  • Richard G With likes this
Thom Greene

#4 Tex

Tex

    Grand Champion Poster

  • Full Member
  • PipPipPipPipPipPipPipPip
  • 9,227 posts
  • Joined: 07-July 06
  • Gender:Male
  • Location:Denton, TX

Posted 27 November 2017 - 12:38 PM

Rich, I've heard of a lot of excuses but this ones a real winner!  

 

Seriously, it looks like the shaft hit the lead 5 or 6 times..........  First of all I cant believe you ran into the wall that often nor that you hit once and the chassis flexed 5 or 6 times?   

 

I didn't run into the wall(much) on race day.... this all happened the previous Sunday during testing/tuning.


Richard L. Hofer

Remember, two wrongs don't make a right... but three lefts do! Only you're a block over and a block behind.

#5 Tex

Tex

    Grand Champion Poster

  • Full Member
  • PipPipPipPipPipPipPipPip
  • 9,227 posts
  • Joined: 07-July 06
  • Gender:Male
  • Location:Denton, TX

Posted 27 November 2017 - 12:39 PM

Is your motor screwed or soldered in?  You might think about stripping it down and heat the chassis up on a flat plate to "relax" the rails.

 

The motor is both screwed AND soldered in. I'm not happy with the chassis anyway, so this will go in the old chassis bin as soon as I build a new one.


Richard L. Hofer

Remember, two wrongs don't make a right... but three lefts do! Only you're a block over and a block behind.

#6 SlowBeas

SlowBeas

    Troublesome De-slotter

  • Subscriber
  • PipPipPipPipPip
  • 994 posts
  • Joined: 15-January 07
  • Gender:Male
  • Location:Lost in South Carolina, USA

Posted 27 November 2017 - 12:59 PM

Unless I'm mistaken, it appears to be strictly a flex issue. I would think that reinforcing the rigidity around the motor would help. Maybe a short L-brace attached to the motor bracket and main rails? Of course, it could also affect handling, so it would require a little track time.

 

That's something I've never seen before. Amazing photos!


Jim Beasley
South Carolina, USA

"Assuming either the Left Wing or the Right Wing gained control of the country, it would probably fly around in circles."
- Pat Paulsen, 1968
"I drive way too fast to worry about cholesterol."
- Steven Wright ca. 1983

#7 Uncle Fred

Uncle Fred

    Checkered Flag in Hand

  • Full Member
  • PipPipPipPipPipPip
  • 1,367 posts
  • Joined: 29-September 06
  • Gender:Male
  • Location:Northlake, TX

Posted 27 November 2017 - 01:25 PM

Have you tried manually bending the chassis to see if you can make the shaft hit the lead?  Personally I cant imagine the chassis bending that much.


Fred Correnti

#8 Pablo

Pablo

    Builder

  • Administrator
  • PipPipPipPipPipPipPipPip
  • 18,364 posts
  • Joined: 20-February 06
  • Gender:Male
  • Location:Cleveland, Tennessee

Posted 27 November 2017 - 05:44 PM

I'd like to see pics of the chassis to see what would allow that much movement :o


Paul Wolcott


#9 Mike K

Mike K

    Checkered Flag in Hand

  • Full Member
  • PipPipPipPipPipPip
  • 1,338 posts
  • Joined: 20-February 06
  • Gender:Male

Posted 27 November 2017 - 06:34 PM

Broken chassis?


So much DRAMA for such small cars....
Mike Kravitz

Don't DQ me for having the wrong SHADE of orange on my McLaren... after all, it's ONLY a toy car!!!


#10 JimF

JimF

    Posting Leader

  • Full Member
  • PipPipPipPipPipPipPip
  • 2,220 posts
  • Joined: 20-June 07
  • Gender:Male

Posted 27 November 2017 - 06:34 PM

Seems to me that the chassis itself would bottom out before it would be possible to bend far enough for that shaft to hit. (unless there were a broken solder joint like maybe one side of the bracket to the main rails)


Jim Fowler

#11 Cap Henry

Cap Henry

    CHR Cars

  • Subscriber
  • PipPipPipPipPipPipPip
  • 3,358 posts
  • Joined: 25-October 08
  • Gender:Male
  • Location:Bellevue, OH

Posted 27 November 2017 - 06:50 PM

How long is the WB?

 

I'm assuming the car is fairly soft, or long. I had an F1 car that I built super long at 4.25" WB for the Sano, in the bottom couple lanes at Mikes it would throw sparks because the car would bow and the motor would rub the track, and the motor didn't hang out the bottom when on the test block.



#12 Tex

Tex

    Grand Champion Poster

  • Full Member
  • PipPipPipPipPipPipPipPip
  • 9,227 posts
  • Joined: 07-July 06
  • Gender:Male
  • Location:Denton, TX

Posted 27 November 2017 - 06:54 PM

The car would "skate" and launch going over a "bridge" and hit quite hard, almost dead-on square; that's what was causing the bowing, NOT normal running. I guess I should said that before.  LOL


Richard L. Hofer

Remember, two wrongs don't make a right... but three lefts do! Only you're a block over and a block behind.

#13 Cap Henry

Cap Henry

    CHR Cars

  • Subscriber
  • PipPipPipPipPipPipPip
  • 3,358 posts
  • Joined: 25-October 08
  • Gender:Male
  • Location:Bellevue, OH

Posted 27 November 2017 - 07:04 PM

scratch my theory then LOL


  • tonyp likes this

#14 Mr. M

Mr. M

    Race Leader

  • Full Member
  • PipPipPipPipPip
  • 519 posts
  • Joined: 04-July 11
  • Gender:Male
  • Location:Florida Space Coast

Posted 27 November 2017 - 07:15 PM

Is the motor going down or is the lead part of the chassis coming up? Not obvious.
Chris McCarty

#15 Samiam

Samiam

    Posting Leader

  • Subscriber
  • PipPipPipPipPipPipPip
  • 4,747 posts
  • Joined: 18-January 12
  • Gender:Male
  • Location:Long Island, NY

Posted 27 November 2017 - 07:22 PM

The hit marks are all over the place too. I think something is broken at the motor bracket..


Sam Levitch
 
"If you have integrity, nothing else matters, and if you do not have integrity, nothing else matters."
    Robert Mueller, special counsel (2013)
 
"... because people have got to know whether or not their president is a crook."
    Richard M .Nixon, Nov 17, 1973
 
"Fool me once, same on... shame on you. Fool me... you can't get fooled again."
    George W. Bush

#16 MSwiss

MSwiss

    Grand Champion Poster

  • IRRA National Director
  • PipPipPipPipPipPipPipPip
  • 25,623 posts
  • Joined: 16-April 06
  • Gender:Male

Posted 27 November 2017 - 07:31 PM

The car would "skate" and launch going over a "bridge" and hit quite hard, almost dead-on square; that's what was causing the bowing, NOT normal running. I guess I should said that before.  LOL

So you launched, hit the wall real hard, but didn't bother to check if you bent the chassis, and subsequently hit the wall another 4 or 5 times, and still didn't check the chassis? :wacko2:


  • tonyp and Tim Neja like this

Mike Swiss
 
Inventor of the Low CG guide flag 4/20/18
IRRA® Components Committee Chairman
Five-time USRA National Champion (two G7, one G27, two G7 Senior)
Two-time G7 World Champion (1988, 1990), eight G7 main appearances
Eight-time G7 King track single lap world record holder

17B West Ogden Ave., Westmont, IL 60559, (708) 203-8003, mikeswiss86@hotmail.com (also my PayPal address)

Note: Send all USPS packages and mail to: 692 Citadel Drive, Westmont, Illinois 60559


#17 tonyp

tonyp

    Grand Champion Poster

  • Member at Peace
  • PipPipPipPipPipPipPipPip
  • 15,325 posts
  • Joined: 12-February 07
  • Gender:Male
  • Location:Sanford, FL, land of lizards and big roaches

Posted 27 November 2017 - 07:50 PM

Lol!!!!!
  • Tim Neja likes this

Anthony 'Tonyp' Przybylowicz

5/28/50-12/20/21
Requiescat in Pace


#18 Tex

Tex

    Grand Champion Poster

  • Full Member
  • PipPipPipPipPipPipPipPip
  • 9,227 posts
  • Joined: 07-July 06
  • Gender:Male
  • Location:Denton, TX

Posted 28 November 2017 - 07:20 AM

So you launched, hit the wall real hard, but didn't bother to check if you bent the chassis, and subsequently hit the wall another 4 or 5 times, and still didn't check the chassis? :wacko2:

 

Well, I needed the trigger time regardless... you make it sound so.... so?..... unproductive.  lol


  • MSwiss and Racer36 like this
Richard L. Hofer

Remember, two wrongs don't make a right... but three lefts do! Only you're a block over and a block behind.





Electric Dreams Online Shop