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alga
9th January 2010, 12:56 AM
Hi, what are the pros & cons of the ally and steel floors? Ally is lighter, steel is cheaper? Is that it?

Due to lower electrode potential the ally floor will protect the chassis from corrosion, by oxidising itself. Somehow I doubt that dipping rivets into silicone will electrically isolate the floor from chassis. A contact will appear in one place or another.

On a related question, why is everyone so keen on fabbing the tank out of sheet ally? 1 mm mild steel sheet would be so much easier to DIY (MIG FTW!), and it would weigh only around 5 kilos. Are 2-3 kg savings worth the effort and the expense, or are there other benefits I'm missing? :confused:

Tilly819
9th January 2010, 01:06 AM
hi alga

as far as i now thats about it ally is lighter and does not go rusty on the under side of the car. though its midnight and iv just come in from the garage so am very tired..

i have an ally floor and tank floor is 1.7mm tank is 1.6mm i think.

my theory wilst bulding has been that iff you can take a little weight off eash part even iff it is only grams in some cases it all adds up and at the end of the day you may walk away with a 20KG weight saving and in a 500-600kg car 20KG is quite abit.

hope this helps

tilly

Peter-C
9th January 2010, 01:16 AM
I intended to go down the steel floor road as i thought that this would add rigidity to the chassis. But after hearing glowing reports of sikaflex, I am going down the ally route. I've spoken to people who have used sikafelx for years and they've said why rivet it just glue it. Sikaflex and rivets, its the future !!

Peter

alga
9th January 2010, 02:29 AM
Just thought of one more advantage of steel floor -- it can be welded quite early in the process and gotten over with, whereas aluminium needs a painted chassis, which needs most of the fixings sorted, which requires trial fitting most components...

aerosam
9th January 2010, 09:25 AM
My floor is 2mm ally chequerplate. This is mainly due to the fact i was given the sheet by cjtheman for nothting!

Getting back onto the subject of tanks, I'm planning on making mine from steel and mig welding it all up - has anyone else done it?

I need to make mine bespoke to fit my donor's pump/level sender assembly and it would be much cheaper to fab one up myself than have one custom made for me.

twinturbo
9th January 2010, 09:41 AM
I doubt corrosion of a steel pan is going to be a major issue.

As long as it has a good paint and stone chip protection it will last for many many years. Especialy given the relativly low milage and normaly fair weather use.

An annual inspection and rectification schedule would be wise..

The steel pan could be replaced with relative ease anyway.

You could always go for a sheet of Galvo.

TT

dogwood
9th January 2010, 09:51 AM
Alloy floor in mine 2mm thick.
But steel tank 1mm if I remember correct.

Reason....Thats what I had.:D

David

flyerncle
9th January 2010, 11:12 AM
A thought,both ends of the chassis are open. So before sealing them why not fit the floor and then squirt Waxoil or some thing like it down the rails and then seal them off,in that way you will have anti corrosion from the inside out if you get my drift.