#Rotor
|
| posted on 7/3/07 at 06:26 AM |
|
|
I am indeed considering it, yes.
would the stresses at the bottom joint be more than at the top, or is it more a case of leverage being more on the bottom as a result of the
cross-bar being there. I personally was a bit more concerned with the cross-bar not being strong enough and maybe bending, but got told by someone in
the know, that since both ends of the bar will be pullingpushing simultaneously, it's as if you have only one single rod-end in the middle.
granted that for wheel twist, one might want that joint a lot wider. It's the hole idea of having that rod at the bottom, for leverage to keep
the wheel looking forward....I think.. 
|
|
|
|
|
Fred W B
|
| posted on 7/3/07 at 08:06 AM |
|
|
You want to be sure that you are not going to get any deflection that would cause movement in the toe in-out plane, as the handling would then be very
strange.
Cheers
Fred W B
|
|
|
sgraber
|
| posted on 7/3/07 at 01:35 PM |
|
|
I am fairly certain that you will see some type of deflection (toe-change) across that lower bush tube under load. Which would be bad. I would
possibly start possibly by gusseting it with a triangle shaped sheet steel u-bent along the outer chord and perimeter welded along each side. (Did
that make sense?)
Wasn't it Stanisforth that noticed over an inch of deflection on the Terrapin rear suspension when the tire width was increased?
Steve Graber
http://www.grabercars.com/
"Quickness through lightness"
|
|
|
akrallysport
|
| posted on 9/3/07 at 03:34 AM |
|
|
quote:
Originally posted by MikeRJ
Everything looks very nicely made except the rear lower wishbones. I don't think the tube welded halfway along one of the wishbone tubes going
to the upright is a very nice design at all, it's almost deliberately loading a stressed part in bending. It should also be mounted on a pivot
if he is using that arm to adjust toe.
This was one of the first things I learned from my first Formula SAE car. Our suspension guy did this
and proceeded to get whacked on the head (figuratively speaking) by a design judge. With only 65hp and 47ft-lb of torque we got massive resonance
under power causing variations of +-2 deg of toe. Otherwise, a great design for a first-time builder.
#Rotor, don't worry about your modded front axle solution. Lotus has something very similar in the Elise. It's probably the cleanest, most
cost-effective way of going about building middy uprights.
[Edited on 9/3/07 by akrallysport]
|
|
|
kb58
|
| posted on 9/3/07 at 05:45 AM |
|
|
I'm afraid I have to join in on the negative comments about the rear lower T-arrangement. It's going to cause toe-in/out under
acceleration/braking. Going to make for some odd-feeling handling, at best. At worst, it'll cause the car to experience brake-induced
oversteering; the last place you need that to happen.
It needs to be fully boxed, like the excellent job you did on the rest of the assembly.
Mid-engine Locost - http://www.midlana.com
And the book - http://www.lulu.com/shop/kurt-bilinski/midlana/paperback/product-21330662.html
Kimini - a tube-frame, carbon shell, Honda Prelude VTEC mid-engine Mini: http://www.kimini.com
And its book -
http://www.lulu.com/shop/kurt-bilinski/kimini-how-to-design-and-build-a-mid-engine-sports-car-from-scratch/paperback/product-4858803.html
|
|
|
#Rotor
|
| posted on 9/3/07 at 05:19 PM |
|
|
Well a revised design is allready been sent to the laser-cutter..... a whopping total of R19.87 (that's like just over a pound) Materials
included, will get both uprights, nicely boxed.... will have pics shortly....
|
|
|
Fred W B
|
| posted on 9/3/07 at 05:45 PM |
|
|
Jees Rotor, at that pricing can I send you some dwg files?
Port Elizabeth has only one lazer cutting company........minium charge of several hundred rand 
Cheers
Fred W B
[Edited on 9/3/07 by Fred W B]
|
|
|
#Rotor
|
| posted on 9/3/07 at 06:55 PM |
|
|
Sure, I can have it priced and then you can decide.
just include the material, the gauge and how many copies there of..... I'll put it into my Template I use for them and lets see how much they
will charge...
it's the kind of material that makes it expensive, the cutting itself is cheap....
for instance to make a fueltank from 304 stainless, would cost me just under R980. to do the exact same cut, but from mild steel, cost me no more the
260, same gauge, same everything, just the material...
|
|
|
Doug68
|
| posted on 10/3/07 at 10:11 AM |
|
|
Lovely.
|
|
|
geoffreyh
|
| posted on 10/3/07 at 06:13 PM |
|
|
Do you make the cutouts (I don't know how you call that in english) into the cylinder yourself or are they premanufactured?
How do you get it to the right diameter for the bearings?
Geoff
|
|
|
kb58
|
| posted on 10/3/07 at 07:16 PM |
|
|
Exactly!
quote:
Originally posted by #Rotor
here is what it should have looked like, yes?
Mid-engine Locost - http://www.midlana.com
And the book - http://www.lulu.com/shop/kurt-bilinski/midlana/paperback/product-21330662.html
Kimini - a tube-frame, carbon shell, Honda Prelude VTEC mid-engine Mini: http://www.kimini.com
And its book -
http://www.lulu.com/shop/kurt-bilinski/kimini-how-to-design-and-build-a-mid-engine-sports-car-from-scratch/paperback/product-4858803.html
|
|
|
#Rotor
|
| posted on 26/4/07 at 08:08 PM |
|
|
well she started up on the 3rd try......
still busy sorting some glitches..... but the motor sounds awesome.....
[Edited on 13/9/07 by #Rotor]
|
|
|
#Rotor
|
| posted on 5/5/07 at 08:23 PM |
|
|
Well, She gave her first steps today.... a whee bit shaky at first, but after a little tweaking on the wheel-alignment and ride height, she got into
some respectful shape....
The ECU is on a First-startup map and yet she has the responsiveness that makes all else fade into insignificance.... front brakes are positively
potent,
|
|
|
akumabito
|
| posted on 6/5/07 at 06:53 AM |
|
|
Wow! Nice build 
|
|
|
#Rotor
|
| posted on 9/5/07 at 05:28 AM |
|
|
Thank you
[Edited on 13/9/07 by #Rotor]
|
|
|
rav
|
| posted on 10/5/07 at 09:30 PM |
|
|
Really impressed by the standard of workmanship and proffesionalism of your build. And for daring to do a lot of the things most folk on here have
got as far as talking about...
The fabricated uprights look superb. Any more info on them? Would love to know how much they ended up weighing and what geometry you went for - KPI,
scrub radius etc?
Anyway, respect!
|
|
|
#Rotor
|
| posted on 13/5/07 at 05:46 PM |
|
|
now here she is fully dressed, only thing missing is the windshield....
this is looking more like something to be seen in......
[Edited on 13/9/07 by #Rotor]
|
|
|
Uphill Racer
|
| posted on 13/5/07 at 09:01 PM |
|
|
Looks good, one thing that stands out is the top wishbone inner location points (loads not fed into chassis but into tube) just one of my pet hates,
but then, I am a grumpy old man.
|
|
|
JonBowden
|
| posted on 14/5/07 at 08:50 AM |
|
|
Very impressive.
How do you make the long sweeping curved tubes at the sides?
Jon
|
|
|
Peteff
|
| posted on 14/5/07 at 09:15 AM |
|
|
I like it apart from the scoop over the engine, it's going to create a lot of drag for little effect. If the engine was boxed in I could
understand it but a flat deck with mesh in it would do the job.
yours, Pete
I went into the RSPCA office the other day. It was so small you could hardly swing a cat in there.
|
|
|
#Rotor
|
| posted on 14/5/07 at 05:39 PM |
|
|
true that scoop will be a lot of drag, but remember that the Intercooler sits inside that scoop, and it needs all the cool air it can get....
Uphill Racer, you have an interesting point there, yes. And I'm open to any suggestion as to solving it..... though I already have the second
car's frame altered around the suspension mainly... to try and solve that problem...
|
|
|
JonBowden
|
| posted on 18/5/07 at 12:04 PM |
|
|
How did you make the curved side tubes?
Jon
|
|
|
geoffreyh
|
| posted on 18/5/07 at 12:11 PM |
|
|
If I remember correctly Rotor contracted the bending to a metal working company.
Another guy who is scratch building his Atom built something to bend his pipes.
Have a look on the following link.
http://www.locostusa.com/forums/viewtopic.php?t=1503&postdays=0&postorder=asc&start=45
|
|
|
Alan B
|
| posted on 18/5/07 at 03:28 PM |
|
|
quote:
Originally posted by JonBowden
How did you make the curved side tubes?
This is what I did...
http://www.locostbuilders.co.uk/viewthread.php?tid=56045
|
|
|
#Rotor
|
| posted on 19/5/07 at 07:52 AM |
|
|
indeed yes... I'm a very lazy person.... that much effort, and I'll just give up....
[Edited on 13/9/07 by #Rotor]
|
|
|
