This is what the field setup instructions allows:

From: http://www.usfirst.org/uploadedFiles/Community/FLL/CC-FIELD-SETUP.pdf

Step 4 With help from another person, pull the mat at opposite ends, then massage out any waviness from west to
east and re-check the requirement of Step 3. It is expected that some waviness will persist, but that should relax over
time. Some teams use a hair dryer to speed the relaxation of the waviness.

Field Mat Make sure the mat rests evenly at the bottom of the south and east border walls. Avoid cleaning
the mat with anything that will leave a residue. Any residue, sticky or slippery, will affect the robot's
performance compared to a new mat (many tournaments use new mats). Use a vacuum and/or a damp cloth
for dust and debris (above and below the mat). When moving the mat for transport and storage, be sure not to
let the material bend into a sharp kink point, which could affect the robot's movement. Many consistent
repetitions of rubbing on the same areas of your practice mat should be expected to cause wear in the image,
but such wear is unlikely at a tournament. Tournaments using new mats should unroll the mats as far in
advance of the tournament day as possible. For control of extreme curl at the east or west edges of the mat,
tape is allowed, with a maximum of ¼" (6 mm) overlap. Do not use tape under the mat.
 

-----Original Message-----
From: First Lego League Discussion [mailto:[log in to unmask]] On Behalf Of Michael Blanpied
Sent: Thursday, October 09, 2008 11:29 AM
To: [log in to unmask]
Subject: [VADCFLL-L] Wavey mat

Does anyone else have an issue with wave in the mat this year?

Our mat won't lie completely flat on the table. The outer edge does, all the way around, but the middle has waves running north-south. 
It's as if the middle perhaps 50% of the area has been slightly stretched east-west and is slightly too big for its surroundings. I'm not sure if the waves are big enough to be affecting the robot's travel, but they're certainly prominent.

I'd be curious to know if anyone else has this problem, and to know of any workable solutions.

Thanks,
--
Mike Blanpied
Reston, VA
2006 Nano People #4809
2007 Power Bunnies #1666
2008 {Name TBD} #5013

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