Jump to content

Hot dip vs cold galvanising for a 911 body


Russ

Recommended Posts

So, as part of my 'long term' restoration plan I've been thinking about getting the body galvanized again

 

cold galvanising is basically just a zinc coating that is painted onto the car, whereas hot dip is submerging the car and using galvanising/electrolisis to get the zinc to bond to steel.

 

I know that as of 76-77 whole cars were galvanized, but does anyone know for sure if it was hot dip?

 

I can only assume so, but from the stuff we do at work any large panels warp when hot dipped - i was wondering how they got around this?

 

anyone got any information on the subject?

Link to comment
Share on other sites

So, as part of my 'long term' restoration plan I've been thinking about getting the body galvanized again

 

cold galvanising is basically just a zinc coating that is painted onto the car, whereas hot dip is submerging the car and using galvanising/electrolisis to get the zinc to bond to steel.

 

I know that as of 76-77 whole cars were galvanized, but does anyone know for sure if it was hot dip?

 

I can only assume so, but from the stuff we do at work any large panels warp when hot dipped - i was wondering how they got around this?

 

anyone got any information on the subject?

Small panels expertly welded together!

 

Some info here 

Link to comment
Share on other sites

Thanks tazzieman, that's some great info.

 

So they dip the individual panels, then weld them together? so they had to remove the zinc from the welds then 'cold paint' the zinc on the joint? Guess it's not something that can be easily replicated with a complete bodyshell

 

This seems like the go now though - e-coating! - I assume this resolves the issues with paint reactions too

http://forums.pelicanparts.com/porsche-911-technical-forum/324520-full-emersion-baths-factory-paint-prep-please-educate-me.html#post3035315

 

DSC007391168677116.jpg

Link to comment
Share on other sites

When I fully restored my 69 Holden, I had similar thoughts on the best way to preserve the body.

The car was stripped to a bare shell, after much research I ended up spraying wurth cavity wax using their special gun and injecting rods.

Car is still perfect some 10 years after it was done.

https://insyncro.wordpress.com/2012/08/23/underbody-spraying-and-cavity-waxing-made-easy-with-the-wurth-multi-sprayer/

http://www.wurth.co.nz/cat/files/assets/downloads/page0112.pdf

Link to comment
Share on other sites

So they dip the individual panels, then weld them together?

Russ,

Just to clarify, they press the panels out of sheet steel that has already been hot dipped galvanised and then weld these separate panels together to form a body.

Link to comment
Share on other sites

E coating requires holes in the body for the carrier liquid to pass through to all the internal cavities and also drain out leaving a dry shell. These are designed in the panels from factory. If your car predates this process the holes won't be there. The cavities will remain unprotected.

Link to comment
Share on other sites

In a car plant in the U.K., a 65mm CDSA™

seal was fitted to an IDP centrifugal pump,

model Frame 4. The duty being pumped was

electro paint operating with a shaft speed of

1440 rpm, with an inlet pressure of 25 psi (1.7

bar) and outlet pressure 90 psi (6.2 bar). The

seal faces were TC/TC//CRO2/C with Viton®

elastomers and 316L wetted parts. The

mechanical seal operated with an SSE10™

W2 system.

Geezus Harvs!

That's getting too anorak, even for me! LOL

Link to comment
Share on other sites

For those with a lesser attention capacity   :huh:

 

This footage shows a typical modern ELPO process line.  The rolling action as the car is dipped ensures the liquid flows through all the body cavities and drains effectively.

 

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...