Printable Version | Subscribe | Add to Favourites
New Topic New Poll New Reply
Author: Subject: Galvanising Bodyshell
scootz

posted on 24/2/10 at 05:04 PM Reply With Quote
Galvanising Bodyshell

Is there anywhere in the UK that can galvanse a full car bodyshell???

Cheeeeeers!





It's Evolution Baby!

View User's Profile View All Posts By User U2U Member
v8kid

posted on 24/2/10 at 05:12 PM Reply With Quote
Scottish Galvanisers off the M8/M77 junction. It may distort due to the heat of the molten zinc though.
View User's Profile E-Mail User Visit User's Homepage View All Posts By User U2U Member
scootz

posted on 24/2/10 at 05:59 PM Reply With Quote
Cheers!





It's Evolution Baby!

View User's Profile View All Posts By User U2U Member
mcerd1

posted on 24/2/10 at 06:00 PM Reply With Quote
and you need to drill massive galv. flow holes in it everwhere other wise it won't work

oh and scottish's bath is only ~1100mm wide (practicaly you can fit anthing up to 1000mm wide or just a little bigger)
Birtley have got a bath a bit wider though

we send anything up to 6 lorry loads of steel a week to scottish and other places - so if you want to know more I can ask





-

View User's Profile View All Posts By User U2U Member
scootz

posted on 24/2/10 at 06:11 PM Reply With Quote
Cheers Robert! Would need something about 2m wide... rules that one out!





It's Evolution Baby!

View User's Profile View All Posts By User U2U Member
mcerd1

posted on 24/2/10 at 06:15 PM Reply With Quote
We got a complete list of all the galv bath sizes at work somewhere (we had alot of problems with that sculpture)





-

View User's Profile View All Posts By User U2U Member
scootz

posted on 24/2/10 at 06:20 PM Reply With Quote
Fantabulous!





It's Evolution Baby!

View User's Profile View All Posts By User U2U Member
Mark Allanson

posted on 24/2/10 at 06:23 PM Reply With Quote
You are going to end up with a very weak, very heavy shell - is it worth it?





If you can keep you head, whilst all others around you are losing theirs, you are not fully aware of the situation

View User's Profile Visit User's Homepage View All Posts By User U2U Member
scootz

posted on 24/2/10 at 06:58 PM Reply With Quote
But plenty of cars have galvanised shells???

I think I need to understand the process a bit more! Can anyone help with a practical guide as it relates to car bodyshells?





It's Evolution Baby!

View User's Profile View All Posts By User U2U Member
mcerd1

posted on 24/2/10 at 07:20 PM Reply With Quote
I don't think they hot-dip galv them

what about the coating those rust removal dipping places use ?





-

View User's Profile View All Posts By User U2U Member
scootz

posted on 24/2/10 at 07:40 PM Reply With Quote
I don't know an awful lot about it Robert... just trying to establish what the best protective coating is for a car bodyshell!





It's Evolution Baby!

View User's Profile View All Posts By User U2U Member
Ivan

posted on 24/2/10 at 07:55 PM Reply With Quote
Yeah - I'm willing to bet they are either electro-galvanized and possibly passivated or cold galvanised - there is no reasonable way as far as I am concerned to get an even, run and drip free finish by hot dipping - and imagine trying to smooth it up for painting.

Not even sure if you could ever end up with a smooth enough finish with hot dipping without lots of heavy and labour intensive filling - something that would be an anathema to car manufacturers.

View User's Profile View All Posts By User U2U Member
will121

posted on 24/2/10 at 07:59 PM Reply With Quote
there was bit in PPC mag this month about paint removal/acid dipping and protective spraying think it was called E-coating, they said around £700 for acid dipping and another £800 for the E-coating think E-coating is electrophoretic coating (what ever that is!!)
link

The Electrophoretic Coating System - THE ULTIMATE CORROSION PROTECTION COATING
The Electrophoretic (e-coat) painting process is universally used on all modern vehicle shells, bracketry and panels. Designed to offer in excess of 1000 hours salt spray resistance* it is widely regarded as the best available anti-corrosion primer paint for mild steel. The shell and parts are immersed in all stages of cleaning, phosphating and painting and this provides excellent penetration into seams, box sections and other areas that would be impossible to coat with a spray gun. The shell and skid are attached to a conveyor which carries them through the complete painting process. At each stage the shell is tilted forwards and backwards to reduce the formation of air pockets and improve solution and paint penetration.

Stage 1. Pre-Treatment
An 8 stage process covering Cleaning, Conditioning and Phosphating. The cleaning process utilises varying strength alkaline silicate solutions at 50ºC to remove oil and grease followed by water rinses. Following a conditioner rinse the shell is immersed in a bath of phosphoric acid with a zinc, manganese and nickel (tri-cation) solution. Water rinses remove the excess phosphate solution and finally the shell is rinsed with demineralised water.

Stage 2. Electrophoretic Deposition
The shell / part is fully immersed into the 130,000 litre PPG paint tank at 33ºC and an electrical current of approx 320 volts drawing around 1000 amps is passed through it. Whilst the shell is tilted forwards and backwards a highly uniform paint film of between 22 μm and 28 μm is fully bonded to all surfaces via a process known as electrophoresis. It is then removed from the paint and rinsed with a low molecular resin solution called Ultra Filtrate. The excess paint and ultra filtrate are then returned to the paint tank – minimizing waste. The shell is then tilted to drain before being cured.



Stage 3. Curing
The shell is then passed through a high temperature oven at 180ºC. This will cross-link the polymer resin allowing the coating to fl ow out and become smooth and continuous. Not only does it cure the paint the high temperature also drives out any moisture from within the seams and box sections. Once cured, the colour may vary from panel to panel due to differences in steel thickness - this does not affect the performance of the coating. The shell is then ready to be seam sealed and primer coated. The e-coat is compatible

[Edited on 24/2/10 by will121]

View User's Profile View All Posts By User U2U Member
scootz

posted on 24/2/10 at 08:08 PM Reply With Quote
Cheers guys!





It's Evolution Baby!

View User's Profile View All Posts By User U2U Member
mcerd1

posted on 24/2/10 at 08:19 PM Reply With Quote
there is one type of chassis that gets hot dipped (at least the replacement ones) - Landrovers

years ago dax showed me a cobra one they tried for a customer - they reconned that there was anything up to a 50kg lump of zinc stuck in one side (hadn't drained out properly) and they didn't fancy drilling loads of big holes in it to solve this for the next time.....


[Edited on 24/2/10 by mcerd1]





-

View User's Profile View All Posts By User U2U Member
nick205

posted on 24/2/10 at 08:59 PM Reply With Quote
Scootz

I believe production tin tops will be made from pre-galvanised steel sheet. We use a material called Zintec at work which is pre-galvanised sheet steel - available in a range of gauges and more expensive then bare steel.

I think for what you're looking for the above process covered in PPC mag is the best bet. IIRC it wasn't cheap and there were potential issues over damaging the shell if it wasn't sound to start with.

View User's Profile View All Posts By User U2U Member
scootz

posted on 24/2/10 at 09:02 PM Reply With Quote
Perfect... thanks for that guys!

Every day's a school-day!





It's Evolution Baby!

View User's Profile View All Posts By User U2U Member

New Topic New Poll New Reply


go to top






Website design and SEO by Studio Montage

All content © 2001-16 LocostBuilders. Reproduction prohibited
Opinions expressed in public posts are those of the author and do not necessarily represent
the views of other users or any member of the LocostBuilders team.
Running XMB 1.8 Partagium [© 2002 XMB Group] on Apache under CentOS Linux
Founded, built and operated by ChrisW.