LocostUSA.com

Learning how to build Lotus Seven replicas...together!
It is currently June 24, 2021, 1:07 am

All times are UTC - 5 hours [ DST ]




Post new topic Reply to topic  [ 22 posts ]  Go to page Previous  1, 2
Author Message
PostPosted: June 8, 2021, 10:16 pm 
Offline

Joined: July 1, 2011, 2:45 pm
Posts: 17
Some pictures to support my last update. Things have progressed a little more from here but haven't taken snapshots and resized them yet.


Attachments:
exo-duc-front-060321-2.jpg
exo-duc-front-060321-2.jpg [ 43.98 KiB | Viewed 281 times ]
Exo-duke-chassis4-052821-2.jpg
Exo-duke-chassis4-052821-2.jpg [ 39.4 KiB | Viewed 281 times ]
Exo-duke-chassis-052821-2.jpg
Exo-duke-chassis-052821-2.jpg [ 63.02 KiB | Viewed 281 times ]
Exo-Duc-Body-2-2.jpg
Exo-Duc-Body-2-2.jpg [ 87.29 KiB | Viewed 281 times ]
Top
 Profile  
Reply with quote  
PostPosted: June 9, 2021, 12:29 am 
Offline

Joined: July 20, 2009, 1:16 am
Posts: 139
How thick are you planning on making those rear suspension plates? (The ones with all the holes in them)

As drawn I don't believe they'll be even close to strong or rigid enough unless they're so thick that it defeats the purpose of the holes. Have you considered making that piece from box section, similar to the front of a Locost? The lower suspension pickups are also placed mid-span on that member, which is not ideal, as the lower control arm feeds much more load into the chassis than the top one (ignoring the bellcrank at the same point). That point should definitely be triangulated.


Top
 Profile  
Reply with quote  
PostPosted: June 9, 2021, 8:49 am 
Offline
User avatar

Joined: July 17, 2008, 9:11 am
Posts: 5880
Location: West Chicago,IL
I don't usually have much to say about other's designs since I can't see inside your head to see your vision. I do see a few things, mostly related to reaching your goal of 800#. you have big steel where it isn't needed. the first is those big tubes running down the center of the car. Space frame cars don't need that extra weight IMO. You also have excess pieces that could be shortened and/or simply removed. Every oz must be considered in order to meet your goal. For some inspiration, I would recommend you take a look at some Formula Vee designs where the minimum weight is now 1025 pounds with driver.

Is this a street car or a track-only car? If a road car, most states have a rule that the chassis or any other part of the car cannot hit the ground if the car is resting on one rim. I see your lower chassis rails do not meet that requirement as drawn.

I see most all new posts and enjoy seeing others' visions move along. I look forward to seeing yours completed. :cheers:

_________________
Chuck.

“Any suspension will work if you don’t let it.” - Colin Chapman

Visit my ongoing MGB Rustoration log: over HERE

Or my Wankel powered Locost log : over HERE


Top
 Profile  
Reply with quote  
PostPosted: June 9, 2021, 12:36 pm 
Offline

Joined: July 1, 2011, 2:45 pm
Posts: 17
Thanks for the design feedback all! Much appreciated when you sit working in a tunnel!

For the weight i'm ok with 1000lbs and figure it is more realistic as safety and future iteration might require additional beef. I've toyed with the idea of fitting a Tesla model3 motor in the back and making an electric version (though this car was inspired by a Ducati at a stop light sounding so good). As designed right now there are 3 'box' sections that comprise the chassis, the outer sills which are more of a triangle and then the central tunnel which acts like the spine. I'm still in the editing phase, so some tubes may go or move including the 1/2" tubes giving the trellis look (like a Ducati).

Good input on the rear member. This is a concept i've drawn up, it's hard to see but about every 2 holes has a 1" dia tube along with there would be boxing in of the structure around the suspension points. I have yet to trade this with a simple welded tube structure. The pickups as depicted have doubler plates as well to increase thickness.

I'm not sure I understand the comment on the single rim touching the ground/chassis body can't touch ground.


Top
 Profile  
Reply with quote  
PostPosted: June 9, 2021, 2:11 pm 
Offline
User avatar

Joined: July 17, 2008, 9:11 am
Posts: 5880
Location: West Chicago,IL
Here is one reference from https://apps.leg.wa.gov/wac/default.asp ... 204-10-036.

4.6.h. A modified vehicle shall have sufficient ground clearance between the vehicle body chassis and steering components and the road surface on which the vehicle rests so that it will be able to be in motion on its four rims on a flat surface with no other parts of the vehicle touching that surface.

Other states have similar requirements. I seem to remember it was a requirement for resting on any one wheel rim with the other 3 on the tires. The above seems to indicate it is more stringent requiring all 4 corners on the rims. Whether you would have to meet this or not, depends on your state's requirements.

_________________
Chuck.

“Any suspension will work if you don’t let it.” - Colin Chapman

Visit my ongoing MGB Rustoration log: over HERE

Or my Wankel powered Locost log : over HERE


Top
 Profile  
Reply with quote  
PostPosted: June 9, 2021, 6:48 pm 
Offline

Joined: July 20, 2009, 1:16 am
Posts: 139
rx7locost wrote:
Here is one reference from https://apps.leg.wa.gov/wac/default.asp ... 204-10-036.

4.6.h. A modified vehicle shall have sufficient ground clearance between the vehicle body chassis and steering components and the road surface on which the vehicle rests so that it will be able to be in motion on its four rims on a flat surface with no other parts of the vehicle touching that surface.

Other states have similar requirements. I seem to remember it was a requirement for resting on any one wheel rim with the other 3 on the tires. The above seems to indicate it is more stringent requiring all 4 corners on the rims. Whether you would have to meet this or not, depends on your state's requirements.

The obvious dodge that springs to mind is to go through the inspection with 19" wheels and paper thin tyres, so it barely drops at all when a tyre is flat :lol:


Top
 Profile  
Reply with quote  
PostPosted: June 14, 2021, 12:34 pm 
Offline

Joined: July 1, 2011, 2:45 pm
Posts: 17
Beelzeboss - thanks for that reply, helped me understand the rule much better :roll: . After reading the law I still wasn't quite sure what was being stated.

I raised the ground clearance an Inch which brings it close but should work, as well as should make it more streetable.


Top
 Profile  
Reply with quote  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 22 posts ]  Go to page Previous  1, 2

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