Fabrication rust protection

[Guest]

Hi Gareth,
I have been looking into fabricating various things and am debating the
galvanising/powder coat/paint options and whilst the former should
offer better protection my concern would be when the item eventually
gets bashed/damaged.
I know that some have considered galvanising and then powder coating,
but I prefer your idea of galvanising and then painting - at least when
it gets bashed (although for some it might be if) you can touch it up.
--
Regards,
Julian Voelcker
Mobile: 07971 540362
Skype: julianvoelcker
Cirencester, United Kingdom
1994 HDJ80, 2.5" OME Lift

 

[Guest]

Julian
|
| I have been looking into fabricating various things and am
| debating the galvanising/powder coat/paint options and whilst
| the former should offer better protection my concern would be
| when the item eventually gets bashed/damaged.
|
| I know that some have considered galvanising and then powder
| coating, but I prefer your idea of galvanising and then
| painting - at least when it gets bashed (although for some it
| might be if) you can touch it up.
On my old VW camper the original hinges to the elevated roof, fabricated
from stainless steel but welded, rusted within less than a year. (Known
problem - to engineers anyway - you need post-welding treatment if you
are going to weld SS.)
So I took them back and they said "hah! What you need is powder
coating". So they made some new ones and powder-coated them. These took
about 3 years to go rusty.
For comparison my tatty old "little" trailer is made from marine ply and
welded mild steel, the latter being galvanised. It has been filled with
acidic horse poo, left full of damp wood, used as a saw-horse and
generally abused, but except in those areas where the galvanised coating
has been worn off by abrasion and left untreated the steel is in perfect
nick. It was three years old when I bought it 7 years ago....
I'd go for hot dip galvanising every time if you want corrosion
protection.
I accept that the galvanising can get damaged, but small scratches are
self-healing and larger areas can be painted with "cold" galvanising
paint (like "Galvafroid"), or you can get spray undercoat with added
zinc at any car parts shop.
Christopher Bell
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[Guest]

Hi Chris,
Yes, I'm not a fan of Powder coating - a lot of people rave about it, but
as soon as it gets damaged the water slides in underneath and it peels
off.
Bearing in mind that all metal parts for chicken cages have to be
galvanised otherwise they don't last and I have seen some kit still
standing after 35years despite regular covering of wet chicken shit,
probably the most corrosive of them all.
I forgot about that. I wa thinking along the Hammerite lines.
One word of warning though, the first thing I ever got galvanised was
'prescision' made so when I tried to bolt it all together none of the
bolts would fit because all the holes were that little bit smaller so I
ended up having to drill them out again to the right size - DOH!
--
Regards,
Julian Voelcker
Mobile: 07971 540362
Skype: julianvoelcker
Cirencester, United Kingdom
1994 HDJ80, 2.5" OME Lift

 

[Guest]

Julian

| One word of warning though, the first thing I ever got
| galvanised was 'prescision' made so when I tried to bolt it
| all together none of the bolts would fit because all the
| holes were that little bit smaller so I ended up having to
| drill them out again to the right size - DOH!
My first experience of galvanised bolts during construction was even
more interesting.
We were building a 50 storey building (in Cairo) from steel, and a lot
of it was put together with "High Strength Friction Grip" (HSFG) bolts.
These are roughly grade 10.9 bolts, about 3x as strong as mild steel but
with a very small margin between their yield strength and their ultimate
tensile strength. They have to be torqued up to some phenomenal load to
clamp the two bits of parent steel together.
Anyway we also had some galvanised bolts for various bits exposed to the
weather, which we duly torqued up. Over the next few days you would
suddenly hear a popping noise, and a bolt head would come flying down
from a great height.
It turned out that hot-dip galvanising HSFG bolts embrittles them, which
is a Bad Thing when they are torqued up to 90% of their failure
stress.... So we had to take them all out and put cadmium plated ones
in instead.
All good fun, and very little to do with Landcruisers I'm afraid!
CB
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[Guest]

Hello guys,
IMHO powder coating has merely aesthetic function and offers little
protection against rust. Actually it's even worse than paint because
you can hardly see corrosion creeping under a layer of powder coat.
It's only advantage over paint is that it can be applied directly to
hot dip galvanised surfaces without passivisation.
---
Rgds,
Roman (London)
'92 HDJ80

 

[Guest]

Hi Guys
Ok so what are our original bumpers covered in or dipped in, is it
plastic.????
cheers
john 92HDJ 80 1HDT