Gas Tank fabrication & 'Terne'

[ojh]

I thought some on here might find this interesting, early gas tanks were made of 'terne' (radiators too) where the metal has a layer of lead to protect it.  I recently had to make a copy of one of these tanks and heres some pictures of the process:

This is the blank sheet of steel to make the tank, I am 'wiping' the lead onto the sheet, the rust at the top of the sheet is from the flux used and it drove me nuts, it rusted everything even close to the work piece, I had to constantly scotchbrite all the metal to keep it clean enough to work with.

This is the interior baffle section, the ribs are aligned with the tank straps.  In this pic the baffles are upside down, the bottom flanges haven't been notched for the fuel and the metal has yet to be leaded.

Heres the tank coming together, a pair of fixture/clamps hold it together, I may have started to lead the baffles in place.  All that shiny stuff is lead.

Heres the fuel pickup tube assembly, the bottom flange was soldered down and all joints are soldered to a brass bulkhead fitting, much as the original was made.  In retrospect I wish I had placed the pickup assembly directly over the drain - you can see the drain right in front of it - in case of a problem you could pull the drain plug and look up inside the fuel pickup tube in case it got plugged.

Heres the tank along side the original, once completed I coated the outside with Ospho to protect it.

And, here it is ready for reinstallation, after the Ospho I used etching primer, a coat of GM Satin Black and a heavy coat of Rubberized Undercoating.

I think 'Terne' was available from metal suppliers in sheets, it is still made today for the standing seam roofers but I believe they use stainless steel as the coating.  The lead itself is very thin as you wipe it on, it'd be difficult to measure the thickness but I'd guess its just a few mils thick.

Oj

[Hans1]

 

terrific demo of your work,  not many know of tern plate.

 

 

[Flivverking]

Amazing craftsman.

 

What is that tank for? I missed it if was mentioned.

I wonder if the sheet metal for lead  terne coated tanks in the early days were done through a dip process ?

 

The '27 chrysler 70 fuel tank I just salvage as it was badly crushed and rusted inside was heavily lead coated shiny and Smooth outside once paint was removed

It made welding tough and soldering easy peasy.

It required a new inner baffle installed in 2 pieces  A bit clumsy compaired to your excellent work.

The flux rusted the clean metal fast.

[ojh]

The tank is for a '52 Nash-Healey, do you have other pics of your tank?  Interesting how it was made/put together.  

When they were making terneplate they had 80-20 lead/tin to work with, I doubt you can find any sticks of that.

 

Edited:  I just googled 80-20 lead stcks and did find them, I'll have to get some, got 2 more tanks to make.

Edited October 11, 2020 by ojh
clarify (see edit history)

[Rusty_OToole]

Why couldn't you use galvanized steel?

[ojh]

I have to make an exact copy.

[MochetVelo]

You're going all-out for authenticity!  Terne metal was, in recent years, made only in the USA by Follansbee Steel which went under several years ago. It was used primarily for roofing, and was steel sheet with a coating of lead and tin in order to make it rust resistant and easy to solder. They had a stainless steel, also coated with lead/tin. The former required painting every few years. As long as it is painted, it lasts a long time. My 1890 building still has its original terne metal roof and our house has terne metal from the 1880s. The roofers here now use copper. 

 

Phil

[Restorer32]

Terne metal was also used for gaiters. We recently made a set for a '32 Packard and were unable to find Terne metal. We've been told it is no longer being made.