Aloupol
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| posted on 28/11/04 at 11:38 PM |
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I scratched it all....
A mistake on my computer took away my CAD data, I just have to start it again...
  
The pic shows what I had just today morning.....
 
Rescued attachment 041125-1.JPG
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Aloupol
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| posted on 28/11/04 at 11:41 PM |
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And the pedal box, also gone away to a beter world..
What a CB I am......
 
Rescued attachment Pédalier.JPG
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sgraber
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| posted on 29/11/04 at 03:42 AM |
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That totally BLOWS!
What happened? You looked in your recycle bin? There may be other ways of recovering data because even when it is deleted, it's only the pointer
to the data that is deleted. the actual data stays on the drive until it is overwritten by new data... Maybe try posting a plea for help in the
Computer Problems section?
Steve
Steve Graber
http://www.grabercars.com/
"Quickness through lightness"
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Aloupol
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| posted on 29/11/04 at 07:46 AM |
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quote:
Originally posted by sgraber
What happened?
I had an old version of the CAD soft, and I got the CD for the brand new one. So I uninstalled it to install the new one.
The trouble: In the first installation I put the data folder into the soft folder. And the uninstall tool removed it...
I checked for all recovery ways, I recovered a little part but the bigest is gone.
Not that bad, I will need something as 10 hours to rebuilt it all.
Sorry to place this in the wrong section, but now we have finished about computers..
Apart of this, is the design right?
Now I will make the frame stronger, with a bulkhead at knees level and an integrated roll cage.
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Ratman
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| posted on 29/11/04 at 11:30 PM |
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Great to be able to model your plans like this. Looks really good. My suggestion would be to try to place your suspension pick-up points on chassis
node points, and to triangluate all the rectangles that you can. Also, try to make the 4 main longitudinal members members continuous without any
dog-leg. If you can do this, then there is a chance you don't have to use any steel sections greater than 20mm square with wall thickness of
1.5mm, and you can get a complete chassis for under 70kg including roll-over protection. Cheers, Brian
[Edited on 29/11/04 by Ratman]
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Aloupol
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| posted on 1/12/04 at 12:48 AM |
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Thanks for coments..
I plan to place the suspension anchors on legs made with stronger tube (50x30x2,7) to allow changing of positions during the tuning and setup phase.
And also triangulation of each square with round tube of lower diameter.
Like this (picture) it weights 56 kg, it's in 30x30x1,6.
Of course this weight doesn't comprise the weld, the missing braces and some paneling. The 70 kg target seems possible.
Maybe it will be possible to grab some honneycomb in the factory's trash and make a full sandwich paneling of the cockpit area.
I think the kink in the side members is good for stiffness because it makes possible a smooth load path between front box and central area.
To be confirmed by a stiffness analysis I will try to do the folowing days..
[Edited on 1/12/04 by Aloupol]
 
Rescued attachment Chassis041130.JPG
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Mave
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| posted on 1/12/04 at 04:28 PM |
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Better make the engine section connect to the nodes of the passenger section. (in other words; the engine bay will get wider in the front. Try not to
end tubes in the middle of other tubes, try to let them go to the nodes.
I'm sure you'll find that rebuilding your model, after a loss of all data, will go soooooo much faster than the first one. All the
thinking has been done......
Good luck!
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Rorty
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| posted on 2/12/04 at 02:22 AM |
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If you can't achieve straight runs or node-to-node members, then bracing them like in the single-seater base below will spread the loads more
evenly. That way you can keep the wall thickness down to the minimum too.
 
Rescued attachment chassis01.jpg
Cheers, Rorty.
"Faster than a speeding Pullet".
PLEASE DON'T U2U ME IF YOU WANT A QUICK RESPONSE. TRY EMAILING ME INSTEAD!
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sgraber
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| posted on 2/12/04 at 01:27 PM |
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Bracing to the nodes is essential for a stiff chassis. Tubes are great in tension/compression but not bending so you always need to get to a corner
and also triangulate where possible.
One thing you should consider is building balsa models of some of your designs. You will really get a good feel for how stiff the final chassis will
be by twisting the model. Alan Stanisforth recommends this in his book "High Speed Low Cost". I built at least 4 different models while
designing my chassis and each version was stiffer and stiffer. It works a treat!
Graber
Steve Graber
http://www.grabercars.com/
"Quickness through lightness"
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Aloupol
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| posted on 2/12/04 at 06:33 PM |
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Yes, the balsa model seems a good way. I saw it in "Chassis engineering" from Herb Adams.
I've got a soft for tubular structures computing but it's easier to feel things with something in the hands than with too much numbers in
the head....
Taught about it and you're right, the weak point in my design is the kink in the upper side beam which allows it to bend under axial load. In
the lower member it's not an issue due to the cross members.
Gonna sort this tonight.
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