Metal Gauge of Sill plates ?

[RustyBucket]

Can someone tell me what the thickness of the metal used to make the siil plates ? THe metal under the front fenders at the fire wall needs to mended on my SPL.


Thanks
Cam

[C.Costine]

I used 20 gauge for all of my replacement sheet metal. If it wasn't the same it was too close to be able to detect any difference. The only thicker metal that I found in the body is the vertical piece between the wheel wells that the floors and rocker panels attach to. That appeared to be 18 gauge.

[RustyBucket]

Thank you for the information about the metal gauge.
The sills have assorted size holes and pin holes which were hidden under scaling rust. So SURPRISE !! after I took a wire wheel to the end of the sill.
I've got some metal fab coming my way.

THanks
Cam

[greydog]

When you buy the metal, try to get EG (electro galv). It'll wire weld just fine, accepts paint and will give you some degree of rust protection where its difficult to seal.
McMaster Carr or Online Metals will have it.
Dan

[RustyBucket]

Dan - Thanks for the information regarding the Galv metal... I was told that it gives off poisonous gas when welded -
But I saw Andy Connor's web site www.mydatsun.com that he just ground the stuff and stich welded the plate in position.
_ So I better hold my breath and give it shot-- what the hell

[RustyBucket]

Sooo what is the alloy of the Datsun sheet metal ?? 4120 ?? @ .20 " -- Right ??

[greydog]

Galvanized steel is dipped in liquid zinc. It has a failry heavy coating of zinc (your garbage can is a good example).
Galvanneal is made the same way but after the zinc bath, the steel is reheated which sort of bakes the zinc on. Coating is thinner than galvanized but it's not easily scratched off.
EG is electro galv. The coating is thnner still but, since it's plated on, bonds on the surface iron molecules and is nearly impossible to remove mechanically.
The eg burns away very quickly when welded. I've not noticed the typical effect of inhaled zinc oxides (headaches, burning eyes and nose as well as the taste.
Still, I wouldn't stand in a way that my hood collects any welding fumes.
We won't laser cut galvanized sheet on our lasers but have no concerns about cutting EG.
Dan

[greydog]

I doubt it's 4000 series, that would indicate some chrome content.
I'd bet it's more like 1015. Common cold rolled sheet will be 1015-1018.
Dan

[RustyBucket]

Dan-
Thank you for the information !! Your note was ,like taking a course on Metallurgy !!
A wealth of knowledge of that I DON'T have ....

I do known that welding of dissimilar metals will cause rust to start at the location of the welds, wrecking that body work AGAIN
So your recommendation is "Common cold rolled sheet will be 1015-1018, EG (electro galv), 18 to 20 guage " - Correct ??

My Datsun was shipped from Wash. to Maryland- So it survive your winters (and lack of Salt) otherwise it would have been in worse shape..

CAm

[greydog]

Yes, either should work fine.
Dan

[RustyBucket]

Dan..
I'll shop around and hopefully find the metal you spec-ed out.

Thanks Again for the schooling.
The odd thing is, the father of my childhood friend was the head of Metallurgy for Maryland's Bethlehem Steel plant - That Guy KNEW HIS STUFF !!

Cam