Go to Post We are making this up as we go along - please don't confuse us by telling us the way that it really should be done. - dlavery [more]
Home
Go Back   Chief Delphi > Technical > Technical Discussion
CD-Media   CD-Spy  
portal register members calendar search Today's Posts Mark Forums Read FAQ rules

 
Closed Thread
Thread Tools Rate Thread Display Modes
  #1   Spotlight this post!  
Unread 11-01-2006, 05:58
Phil Paspalas Phil Paspalas is offline
Registered User
FRC #1676 (The Pascack Pioneers)
Team Role: Coach
 
Join Date: Jan 2005
Rookie Year: 2005
Location: Montvale, New Jersey
Posts: 26
Phil Paspalas is an unknown quantity at this point
Working with Lexan

Last season, our team used Lexan (polycarbonate) to shield the electronics from damage. We found it easy to cut, bend, de-bur, and generally pretty good stuff! But it's a pain to drill!!!!!!!!!!!!! Especially when trying to drill large holes in it to remove weight. We tryed a hole saw with poor results and regular twist drills were problematic as they get past 3/4". Any suggestions?

Phil Paspalas
Head Coach - Team 1676
The Pascack Pioneers
2005 NJ Rookie All-Stars
  #2   Spotlight this post!  
Unread 11-01-2006, 06:33
663.keith 663.keith is offline
Registered User
FRC #1493 (Falcons)
Team Role: College Student
 
Join Date: Oct 2004
Rookie Year: 2003
Location: Whitinsville Massachusetts
Posts: 250
663.keith is a name known to all663.keith is a name known to all663.keith is a name known to all663.keith is a name known to all663.keith is a name known to all663.keith is a name known to all
Send a message via AIM to 663.keith
Re: Working with Lexan

try lubricating the drill bit with dish soap, it generally produces good results
__________________
http://www.wcsrobotics.com
team 663
team 1493
  #3   Spotlight this post!  
Unread 11-01-2006, 10:07
RoboGeek RoboGeek is offline
Registered User
AKA: Matt Kinnison
#0063 (The Red Barons)
Team Role: Mechanical
 
Join Date: Nov 2004
Location: Erie Pennsylvania
Posts: 6
RoboGeek is an unknown quantity at this point
Send a message via Yahoo to RoboGeek
Re: Working with Lexan

go pick up a set of step drills and use them they will make life alot easier! I suppose it is possile to just use 5 different bits in and step up through them but a step drill will be alot faster and a sharp one will go through lexan like a hot knife through butter! in '04 I personally drilled almost 6000 3/4" holes in sheets of lexan for our bot (we didn't use them as they were still too heavy and if we drilled anymore holes we wouldn't have a side panel lol!!)seriously though get a set and go at it its faster then you think and quite easy!
  #4   Spotlight this post!  
Unread 11-01-2006, 11:22
Greg Needel's Avatar Unsung FIRST Hero
Greg Needel Greg Needel is offline
REVving up for a new season
FRC #2848 (All-sparks)
Team Role: Engineer
 
Join Date: Jan 2002
Rookie Year: 2002
Location: Dallas, TX
Posts: 3,108
Greg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond repute
Re: Working with Lexan

The problem with working with lexan and any other plastics is that they tend to melt before the bit actually chips away at the material. An easy solution for cutting plastics is to turn the drill bit or hole saw slower, this makes less heat and there is less of a likely hood of melting. Alot of lubrication on the bit and material will help as well.
__________________
Greg Needel│www.robogreg.com
Co-founder REV Robotics LLC www.REVrobotics.com
2014 FRC World Champions with 254, 469, & 74
  #5   Spotlight this post!  
Unread 11-01-2006, 13:23
TheAnsweris42's Avatar
TheAnsweris42 TheAnsweris42 is offline
Team 1896 "Rules Guru"
AKA: Kenneth Casperson
FRC #1896 (Xodus)
Team Role: Webmaster
 
Join Date: Jan 2006
Rookie Year: 2006
Location: Traverse City Michigan
Posts: 31
TheAnsweris42 will become famous soon enoughTheAnsweris42 will become famous soon enough
Send a message via ICQ to TheAnsweris42 Send a message via AIM to TheAnsweris42 Send a message via MSN to TheAnsweris42 Send a message via Yahoo to TheAnsweris42
Re: Working with Lexan

So, in your opinion, would lexan or another polycarb be a good choice for the outer shell as well? Some of us think we might want to try and do something like that, because it would make the visibility requirements on the controller and ball bin a lot easier, and would make good protection. We're a rookie team, though, and since we don't have any experience in how rough things might actually get, or how much the polycarb would cost...
__________________
"A common mistake people make when attempting to engineer something completely foolproof is to underestimate the ingenuity of complete fools"
-Douglas Nathaniel Adams
  #6   Spotlight this post!  
Unread 11-01-2006, 13:46
Greg Needel's Avatar Unsung FIRST Hero
Greg Needel Greg Needel is offline
REVving up for a new season
FRC #2848 (All-sparks)
Team Role: Engineer
 
Join Date: Jan 2002
Rookie Year: 2002
Location: Dallas, TX
Posts: 3,108
Greg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond repute
Re: Working with Lexan

Quote:
Originally Posted by TheAnsweris42
So, in your opinion, would lexan or another polycarb be a good choice for the outer shell as well? Some of us think we might want to try and do something like that, because it would make the visibility requirements on the controller and ball bin a lot easier, and would make good protection. We're a rookie team, though, and since we don't have any experience in how rough things might actually get, or how much the polycarb would cost...
As a rule of thumb about lexan/polycarbonate:
load bearing or going to take hits 1/8" or larger

non load bearing plates for numbers and such 1/8" or smaller.

The uses of lexan in FIRST basically come down to how flexible you can accept during use because even with the forces involved in robot collisions i have seen very little polycarbonate break. So the thicker it is the less flexibility you have and vice versa....Plexiglas is another story all together.
__________________
Greg Needel│www.robogreg.com
Co-founder REV Robotics LLC www.REVrobotics.com
2014 FRC World Champions with 254, 469, & 74
  #7   Spotlight this post!  
Unread 11-01-2006, 13:50
Kirk Kirk is offline
Registered User
FRC #0254
Team Role: Engineer
 
Join Date: Jan 2002
Rookie Year: 1997
Location: Woodside, CA
Posts: 97
Kirk has much to be proud ofKirk has much to be proud ofKirk has much to be proud ofKirk has much to be proud ofKirk has much to be proud ofKirk has much to be proud ofKirk has much to be proud ofKirk has much to be proud ofKirk has much to be proud of
Send a message via AIM to Kirk
Re: Working with Lexan

Quote:
Originally Posted by TheAnsweris42
So, in your opinion, would lexan or another polycarb be a good choice for the outer shell as well? Some of us think we might want to try and do something like that, because it would make the visibility requirements on the controller and ball bin a lot easier, and would make good protection. We're a rookie team, though, and since we don't have any experience in how rough things might actually get, or how much the polycarb would cost...
Poly Carb is great for protective panels. If you have supports under it you can go as thin as 1/16" which is what we usually use. Poly Carb is very good for resisting puncture and will not crack. One warning MAKE SURE YOU GET POLY CARB most stores will sell acrylic as poly carbonate. Acrylic is not only not allowed in first but is breaks like glass when it is impacted or bent.

Good luck on your rookie year and feel free to post up if you have questions about anything.

~Kirk
  #8   Spotlight this post!  
Unread 11-01-2006, 13:52
Greg Needel's Avatar Unsung FIRST Hero
Greg Needel Greg Needel is offline
REVving up for a new season
FRC #2848 (All-sparks)
Team Role: Engineer
 
Join Date: Jan 2002
Rookie Year: 2002
Location: Dallas, TX
Posts: 3,108
Greg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond repute
Re: Working with Lexan

Quote:
Originally Posted by Kirk
Acrylic is not only not allowed in first but is breaks like glass when it is impacted or bent.

not true anymore..the restrictions on acrylic and plexi were lifted last year.
__________________
Greg Needel│www.robogreg.com
Co-founder REV Robotics LLC www.REVrobotics.com
2014 FRC World Champions with 254, 469, & 74
  #9   Spotlight this post!  
Unread 11-01-2006, 14:09
Unsung FIRST Hero
Mike Betts Mike Betts is offline
Electrical Engineer
no team
Team Role: Engineer
 
Join Date: Dec 2001
Rookie Year: 1995
Location: Homosassa, FL
Posts: 1,442
Mike Betts has a reputation beyond reputeMike Betts has a reputation beyond reputeMike Betts has a reputation beyond reputeMike Betts has a reputation beyond reputeMike Betts has a reputation beyond reputeMike Betts has a reputation beyond reputeMike Betts has a reputation beyond reputeMike Betts has a reputation beyond reputeMike Betts has a reputation beyond reputeMike Betts has a reputation beyond reputeMike Betts has a reputation beyond repute
Re: Working with Lexan

For safety reasons, I would never allow plexiglass on a robot. Polycarb only. IMHO, FIRST is making a mistake in allowing plexi...

The "step" drill referred to above is usually called an omni-bit. Omni-bit may be a trade name but any hardware store will know what you are looking for. It drills through polycarb like butter.
__________________
Mike Betts

Alumnus, Team 3518, Panthrobots, 2011
Alumnus, Team 177, Bobcat Robotics, 1995 - 2010
LRI, Connecticut Regional, 2007-2010
LRI, WPI Regional, 2009 - 2010
RI, South Florida Regional, 2012 - 2013

As easy as 355/113...
  #10   Spotlight this post!  
Unread 11-01-2006, 14:11
Greg Needel's Avatar Unsung FIRST Hero
Greg Needel Greg Needel is offline
REVving up for a new season
FRC #2848 (All-sparks)
Team Role: Engineer
 
Join Date: Jan 2002
Rookie Year: 2002
Location: Dallas, TX
Posts: 3,108
Greg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond reputeGreg Needel has a reputation beyond repute
Re: Working with Lexan

Quote:
Originally Posted by Mike Betts
For safety reasons, I would never allow plexiglass on a robot. Polycarb only. IMHO, FIRST is making a mistake in allowing plexi...

I agree whole heartly with you i think they did this because sometimes teams only have access to specific materials and plexi is still more common and cheaper then lexan/polycarbonate.
__________________
Greg Needel│www.robogreg.com
Co-founder REV Robotics LLC www.REVrobotics.com
2014 FRC World Champions with 254, 469, & 74
  #11   Spotlight this post!  
Unread 11-01-2006, 15:03
Kirk Kirk is offline
Registered User
FRC #0254
Team Role: Engineer
 
Join Date: Jan 2002
Rookie Year: 1997
Location: Woodside, CA
Posts: 97
Kirk has much to be proud ofKirk has much to be proud ofKirk has much to be proud ofKirk has much to be proud ofKirk has much to be proud ofKirk has much to be proud ofKirk has much to be proud ofKirk has much to be proud ofKirk has much to be proud of
Send a message via AIM to Kirk
Re: Working with Lexan

Quote:
Originally Posted by Greg Needel
I agree whole heartly with you i think they did this because sometimes teams only have access to specific materials and plexi is still more common and cheaper then lexan/polycarbonate.
For those teams that don't know how to tell the difference between the two, the best way to tell is take a pair of pliers and try to bend a corner. If it bends like a piece of soft aluminum its polycarbonate if it cracks or breaks its acrylic.

~Kirk
  #12   Spotlight this post!  
Unread 11-01-2006, 15:09
billbo911's Avatar
billbo911 billbo911 is offline
I prefer you give a perfect effort.
AKA: That's "Mr. Bill"
FRC #2073 (EagleForce)
Team Role: Mentor
 
Join Date: Mar 2005
Rookie Year: 2005
Location: Elk Grove, Ca.
Posts: 2,367
billbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond reputebillbo911 has a reputation beyond repute
Re: Working with Lexan

Quote:
Originally Posted by Kirk
For those teams that don't know how to tell the difference between the two, the best way to tell is take a pair of pliers and try to bend a corner. If it bends like a piece of soft aluminum its polycarbonate if it cracks or breaks its acrylic.

~Kirk
There is nothing like Brute Force Testing to come to a very quick answer.
__________________
CalGames 2009 Autonomous Champion Award winner
Sacramento 2010 Creativity in Design winner, Sacramento 2010 Quarter finalist
2011 Sacramento Finalist, 2011 Madtown Engineering Inspiration Award.
2012 Sacramento Semi-Finals, 2012 Sacramento Innovation in Control Award, 2012 SVR Judges Award.
2012 CalGames Autonomous Challenge Award winner ($$$).
2014 2X Rockwell Automation: Innovation in Control Award (CVR and SAC). Curie Division Gracious Professionalism Award.
2014 Capital City Classic Winner AND Runner Up. Madtown Throwdown: Runner up.
2015 Innovation in Control Award, Sacramento.
2016 Chezy Champs Finalist, 2016 MTTD Finalist
  #13   Spotlight this post!  
Unread 11-01-2006, 16:27
Kirk Kirk is offline
Registered User
FRC #0254
Team Role: Engineer
 
Join Date: Jan 2002
Rookie Year: 1997
Location: Woodside, CA
Posts: 97
Kirk has much to be proud ofKirk has much to be proud ofKirk has much to be proud ofKirk has much to be proud ofKirk has much to be proud ofKirk has much to be proud ofKirk has much to be proud ofKirk has much to be proud ofKirk has much to be proud of
Send a message via AIM to Kirk
Re: Working with Lexan

Quote:
Originally Posted by billbo911
There is nothing like Brute Force Testing to come to a very quick answer.
Other wise its pretty hard to tell them apart if the wraping has been removed.
  #14   Spotlight this post!  
Unread 11-01-2006, 17:18
TheAnsweris42's Avatar
TheAnsweris42 TheAnsweris42 is offline
Team 1896 "Rules Guru"
AKA: Kenneth Casperson
FRC #1896 (Xodus)
Team Role: Webmaster
 
Join Date: Jan 2006
Rookie Year: 2006
Location: Traverse City Michigan
Posts: 31
TheAnsweris42 will become famous soon enoughTheAnsweris42 will become famous soon enough
Send a message via ICQ to TheAnsweris42 Send a message via AIM to TheAnsweris42 Send a message via MSN to TheAnsweris42 Send a message via Yahoo to TheAnsweris42
Re: Working with Lexan

Alright, awesome. Thanks for the advice, did I mention you guys are the best? lol... I'll be showing up now and again, count on it
__________________
"A common mistake people make when attempting to engineer something completely foolproof is to underestimate the ingenuity of complete fools"
-Douglas Nathaniel Adams
  #15   Spotlight this post!  
Unread 11-01-2006, 23:09
Andy Baker's Avatar Woodie Flowers Award
Andy Baker Andy Baker is offline
President, AndyMark, Inc.
FRC #3940 (CyberTooth)
Team Role: Engineer
 
Join Date: May 2001
Rookie Year: 1998
Location: Kokomo, Indiana
Posts: 3,417
Andy Baker has a reputation beyond reputeAndy Baker has a reputation beyond reputeAndy Baker has a reputation beyond reputeAndy Baker has a reputation beyond reputeAndy Baker has a reputation beyond reputeAndy Baker has a reputation beyond reputeAndy Baker has a reputation beyond reputeAndy Baker has a reputation beyond reputeAndy Baker has a reputation beyond reputeAndy Baker has a reputation beyond reputeAndy Baker has a reputation beyond repute
Send a message via AIM to Andy Baker
Re: Working with Lexan

Quote:
Originally Posted by Kirk
Other wise its pretty hard to tell them apart if the wraping has been removed.
Yet another way (and probably the easiest) is to look at the edge of the sheet of plastic.

White or frosted transparent: Acrylic (plexiglas)
Blue frosted: polycarbonate

From what I recall, polycarbonate has a "blueness index". The higher the number, the more blue tint it has. Since 1963, when Dan Fox at GE invented LEXAN, this "blueness index" has gotten lower and lower.

Andy B.
Closed Thread


Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Sources for Delrin and Lexan stock sanddrag Technical Discussion 3 04-12-2005 00:25
Who is working on their team site over the summer? Timothy D. Ginn Website Design/Showcase 15 07-06-2005 18:47
IR Beacon/reciever not working... still... Ferazel2001 Programming 23 04-02-2004 23:30
I'm working :) Jack FIRST Scouting Network 2 03-01-2004 01:26
Whose working this summer? Frank(Aflak) Chit-Chat 20 28-05-2003 11:35


All times are GMT -5. The time now is 08:27.

The Chief Delphi Forums are sponsored by Innovation First International, Inc.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
Copyright © Chief Delphi