LocostUSA.com

Learning how to build Lotus Seven replicas...together!
It is currently Mon Dec 22, 2014 2:24 pm

All times are UTC - 5 hours [ DST ]




Post new topic Reply to topic  [ 1 post ] 
Author Message
PostPosted: Wed Aug 06, 2008 9:21 pm 
Offline
Locostering Information Liaison
User avatar

Joined: Wed Aug 17, 2005 1:30 am
Posts: 2402
Location: So CALIFORNIA
Ok no jokes just the straight stuff....
http://locostusa.com/forums/viewtopic.php?t=2224

Seven-esque stiffness
Quote:
Chassis by the book with 16 gauge sheet steel panels
The stiffness is 1187 ftlbs per degree of twist and the weight is 158 lbs.
With a welded on dashboard structure and considering some of the possible variations in the book the stiffness could be about 1400 ftlbs per degree of twist.

cymtriks' document "Lowcost mods.doc"
Quote:
Chassis with modified front, 18 gauge sheet steel panels and boxed in tunnel with no internal ¾ inch tubes except for front hoop and floor braces.
The stiffness is 2449 ftlbs per degree of twist and the weight is 148 lbs

cymtriks' document "Lowcost mods.doc"
Found at....
http://locost7.info/files/chassis/aussi ... stmods.doc

Aussie Mods
Quote:
Chassis by the book with 16 gauge sheet steel panels
Stiffness is 1180 ftlbs per degree of twist
The weight is 181 lbs.
With a welded on dashboard structure and considering some of the possible variations in the book the stiffness could be about 1400 ftlbs per degree of twist.

Wesley Linton's thesis....
Quote:
The double Y braced chassis, with all the extra diagonals, a modified transmission tunnel and reduced panel thickness has a stiffness of 2683 ftlbs per degree of twist for a weight of 174 lbs. This requires only two extra tubes compared to the book chassis and is ten pounds lighter.

Wesley Linton's thesis, found at....
http://locost7.info/files/chassis/kitcaranalysis_V2.doc

Though this is not the end limits some member have acheived numbers over 6,000 ft lbs per degree of twist (read the topic thread posted above).

Round Tube
While theory abounds round tubing should be sightly lighter and slightly stronger (more rigid) than square tube the general consensus is that round tubing could save you maybe 20lbs per completed frame.

Though nobody has tested the stiffness of a round tube frame only a few kit car manufactures ever produced them.

Aluminum Space Frame
Quote:
Steel tubing is probably the best material for an amateur built space frame chassis. If aluminum tubing is used then the chassis weight will be only one third of the weight of a steel chassis. The stiffness and strength of the chassis will also be only one third of the steel design. The stiffness and strength can be improved by making the tubes bigger but then the chassis weight is increased. It is actually theoretically impossible for a true space frame to be torsionally better or worse in aluminum than in steel for the same weight and similar external tube sizes.

Wesley Linton's thesis, found at....
http://locost7.info/files/chassis/kitcaranalysis_V2.doc

Chrome Molly
http://locostusa.com/forums/viewtopic.php?t=4235

Monocoque
No current locost frame exists besides the troubled Robin Hood. (there are rumored to be several design deficiencies in that product.) There is a general tendency for Aluminum to "work harden", weaken and fatigue, with time,,,this effects the frame strength and integrity. Author Alan Stansforth has built and designed, wrote a book on, and sells plans for a successful Aluminum Monocoque car, no rigidity tests have been run on it to my knowledge.

Carbon Fiber Monocoque
Not Locost not tested or mentioned for this discussion....
Image
IMHO

Other relevant discussions:

http://www.locostusa.com/forums/viewtopic.php?t=1048

_________________
I'll keep an eye out for you!

To err is human...
I am more human than most.


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 1 post ] 

All times are UTC - 5 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
POWERED_BY