scootz
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| posted on 27/7/08 at 04:00 PM |
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Steel v Ali Panels
I've always liked the appeal of welded in floor / interior panels... no risk of bi-metallic corrosion and easy to strip and coat when the time
comes (no rivet holes to worry about!).
Only downsides that I can see are the time to cut / weld the panels in and the weight!
So, 2 questions...
1) What thickness of steel would be required for flooring / interior panelling?
2) Is there a general rule determining how much heavier steel is to ali?
Basically, I'm trying to work out if I could use thinner steel sheet and how that would equate to thicker ali?
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novacaine
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| posted on 27/7/08 at 04:20 PM |
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if you give me a rough drawing of the floor panels i'll stick them in solidworks and work out the dimensions needed
And you run and you run to catch up with the sun but its sinking, Racing around to come up behind you again, the sun is the same in a relative way but
your older, shorter of breath and one day closer to death
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mr henderson
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| posted on 27/7/08 at 04:31 PM |
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quote:
Originally posted by scootz
2) Is there a general rule determining how much heavier steel is to ali?
Yep, its called specific gravity
Aluminum is about 2725 and steel 7850. What you want to know, though, is a bit more complicated.
I suppose you would start by deciding what you wanted the floor to do
eg contribute to the strength or stiffness of the car, keep the water out when driving over a puddle, stop your feet going through if you manage to
stand up in the car.
Tricky subject
John
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NigeEss
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| posted on 27/7/08 at 05:35 PM |
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quote:
Originally posted by mr henderson
I suppose you would start by deciding what you wanted the floor to do
eg contribute to the strength or stiffness of the car, keep the water out when driving over a puddle, stop your feet going through if you manage to
stand up in the car.
Tricky subject
John
Puncture resistance also to protect you.
Nige
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chris_smith
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| posted on 27/7/08 at 06:49 PM |
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if it helps you can easily work out the weight of a panel using mr hendersons figures called weight factors
say you wanted to know the weight of a sheet 2000mm x 1000mm x 1.5mm
steel - 2 x 1 x 1.5 x 7.85 = 23.55kg
ali - 2 x 1 x 1.5 x 2.72 = 8.16kg
a bit of a differance if your looking at saving weight!
iv used steel on the floor and welded it in, everyone to there own though
hth
chris
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scootz
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| posted on 27/7/08 at 06:50 PM |
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Basically, I want a flat floor from tip to tail.
The 2 seating area panels are already steel and come welded into the chassis by the factory. I'd just like to continue this theme.
Unfortunately, I can't measure the thickness of these panels for reference!
There's a fair bit of triangulation on the chassis base, so I'd have to cut each individual piece to suit and would want to seam weld each
in place.
It would be easier to get one large panel to span the entire length and tack weld at regular intervals, but as that would mean that a number of the
cross-members would be bridged causing grot to gather in the gaps and premature corrosion.
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scootz
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| posted on 27/7/08 at 07:00 PM |
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I don't want to build a tank, but I'm not going to get paranoid about 20-30 extra kilos as I'll be pushing it all around with
400-450bhp!
I want a chassis that's easy to maintain.
I've had it with ali panels and rivets... strip it down... weld up the rivet holes... blast it... powder-coat it... re-drill the rivet holes...
re-rivet panels in place... PITA!
I just want to be able to send the whole thing to the powder-coaters without having to go through all that rigmarole every few years!
Also, my car is an open top and I want to be able to drive it in all weathers, so no fabrics in the cockpit and just a few drain holes with removable
rubber bungs! I reckon that a powder-coated interior where all welds are buffed down would be both practical and aesthetically pleasing!
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mr henderson
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| posted on 27/7/08 at 07:40 PM |
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What thickness of aluminium is normally used on Ultimas?
When you know that you will be ablle to select a suitable thickness of steel, which will, of course, be thinner because the thing that many people
forget, when they exalt aluminiums lightness, is the fact that it is nowhere near as strong.
I very much doubt that you will be carrying a noticeable extra weight if you go this route
John
[Edited on 27/7/08 by mr henderson]
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Chippy
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| posted on 27/7/08 at 08:34 PM |
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I did my floor with 1.6 mm sheet steel, and rather than seam weld, I button welded it every three inches in an attempt to not have it
"dong" when I got in, this worked fine, until I put some tacks on the cross members for the seats. Floor now "dong's"
but not a lot. By the way sprayed the chassis and the steel for the floor with weld through primer, prior to the welding. Cheers Ray
To make a car go faster, just add lightness. Colin Chapman - OR - fit a bigger engine. Chippy
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ozzieboy
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| posted on 2/8/08 at 03:14 PM |
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well you should be using the escort roof as the good old book says 
I have gone for the allie option after drilling about 200 m4 holes i wondered why??
IF ITS NOT BROKEN DON'T FIX IT....
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