Jesus-Ninja
|
| posted on 14/12/07 at 01:33 PM |
|
|
guidance on what steel to use?
Righto. I'm building me a car. Well, I say that, I'm designing it at the moment.
The idea is to take my track prepped S14, use the rear subframe, and "clone" the suspension geometry up front, but move the engine back
behind the front axle. The whole lot ot be built into a space frame picking up the existing rollcage.
I'm going to put the whole design through finite analysis, but am lookng afor a bit of guidance as to what steel to use. My intention is to use
two types (primaries and secondaries) of square section.
Could use some thoughts though on section dimensions, wall thicknesses, and recommended limts on sizes and angles of triangles.
|
|
|
|
|
bonzoronnie
|
 posted on 14/12/07 at 02:31 PM |
|
|
Tube sizes
The use of 1.6 mm thick . 1"x1" & 3/4"x3/4". ERW Square tube has been the standard steel for the locost type chassis.
Some may opt for heavier gauge for a competition chassis, on the negative side though, a weight gain penalty.
Ronnie 
|
|
|
twybrow
|
| posted on 14/12/07 at 04:41 PM |
|
|
If weight is a primary concern, am I right in saying that tube is better than box section?
|
|
|
bonzoronnie
|
| posted on 14/12/07 at 06:00 PM |
|
|
Tube
I would have to say yes to tube if weight is the main issue.
This would probably require a chassis redesign. Along the lines of an Atom.
Re-design of a chassis is well beyond my skills.
Ronnie
|
|
|
Jesus-Ninja
|
| posted on 14/12/07 at 09:09 PM |
|
|
quote:
Originally posted by twybrow
If weight is a primary concern, am I right in saying that tube is better than box section?
good question, and one I have though about. Then I keep thinking that square section is so much easier to bond panels and floors to. Not mention
getting things square.
What % weight saving is there going to be, realistically, using round tube rather than square section?
|
|
|
britishtrident
|
| posted on 15/12/07 at 10:34 AM |
|
|
Whatever section of steel you choose make sure it is a mild steel (ERW is mild steel) as this will avoid problems due to brittle fractures at
welds.
Mild steels due to the low carbon content don't become excessively hard (eg brittle) when cooled rapidly from very high temperatures.
Higher strength higher carbon steels become excessively hard when cooled rapidly as happens in the heat affected zone at the edges of he weld, and
can only be used in chassis if bronze welding (eg "brazing" is used.
Most proper stainless steels also suffer from brittle fracture if welded.
[Edited on 15/12/07 by britishtrident]
|
|
|
onzarob
|
| posted on 15/12/07 at 05:25 PM |
|
|
quote:
Originally posted by britishtrident
Most proper stainless steels also suffer from brittle fracture if welded.
[Edited on 15/12/07 by britishtrident]
I always thought a stainless steal chassis would be dangerous as it would tend to crack quicker than a mild steel chassis.
Surprisingly I've seen a few Stainless steal chassis advertised
what are your thoughts 'British trident'
|
|
|
