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niallyc
19th January 2010, 10:38 PM
Hi All,

I have a question that might seem a little dumb but I', going to ask it anyway and hope for the best!

Should I prime my chassis as I go or should I wait till its all finished and do the whole lot? I have just tacked all the bottom rails together and I am concerned that the cleaned surfaces will start to rust. With this (possibly irrational) fear in mind, I began degreasing, sanding and degreasing again. I'm using a u-pol weld through primer on the joints and an acid 8 etch primer elsewhere.

Are my fears of the dreaded oxidisation fairy unfounded? I realise that I'll probably have to clean off the joints again when I want to fully weld them up so there will be a bit of extra work.

Any help on this would be appreciated. I have to go and get some fresh air now! DO NOT paint in the garage with the door closed! :D

AndyLockwood
19th January 2010, 10:51 PM
Im just about to start on my chassis so ill be interested to see what peoples views are.

best of luck with your build

Andy:D

flyerncle
19th January 2010, 10:53 PM
Tack the chassis together,fit and weld brackets on,fully weld everything and then etch and paint.It has beeen discussed here and even after years of use the internals are as good as nearly new with little rust inside the rails as there will be little air and and moisture left inside after welding.
You could squirt Waxoyl or something like it inside if you feel the need and I personally will do this before capping the ends.

Good luck.

RAYLEE29
19th January 2010, 11:00 PM
I hate rust too but my solution was a bit more simple
I had a coffee jar with an oily rag init every time i finshed a section out came the rag and wiped over the rellavent chassis parts with oil
to stop the condensation from my aluminium roof dripping on my chassis i put a membrane stretched across the roof joists above my build area
this worked well and kept my chassis rust free for nearly a year before i painted it obviously you need to degrease before painting
Ray:)

AndyLockwood
19th January 2010, 11:01 PM
now thats a good idea:)

niallyc
19th January 2010, 11:05 PM
I hate rust too but my solution was a bit more simple
I had a coffee jar with an oily rag init every time i finshed a section out came the rag and wiped over the rellavent chassis parts with oil
to stop the condensation from my aluminium roof dripping on my chassis i put a membrane stretched across the roof joists above my build area
this worked well and kept my chassis rust free for nearly a year before i painted it obviously you need to degrease before painting
Ray:)

I've been doing someting similar. After I cut a piece to size I dip the end in a jar of diesel engine oil and give it a wipe with a rag. Then dip the other end and wipe again just to make sure both ends are "sealed".

AshG
19th January 2010, 11:09 PM
if i was to start again and build a new chassis i would paint areas as i went before they rusted as it took me 5 hours to rub the whole chassis down before i painted it.

AndyLockwood
19th January 2010, 11:11 PM
what are people using as the initial coat on the steel?

Andy

dogwood
20th January 2010, 09:41 AM
what are people using as the initial coat on the steel?

Andy

I used Red Oxide Primer...Only because thats what I had.
And yes I did prime as I went. I found the bits I missed (Underneath bottom rails)
were really rusty, took ages to get it all off.

twinturbo
20th January 2010, 09:46 AM
TBH, it's not going to get that bad.

I have had a sheet of 1mm Mild sitting out of the back of the garage in all weather for 18 months. I needed a bit for a repair on the golf. it had surface rust all over. But 2 mins with a sandig disk and the bit i needed was bright and shiney.

I will build mine, etch it and then primer and top coat.

TT

AshG
20th January 2010, 10:51 AM
the difference it its a lot harder to rub down 4 sides in a tight corner than it is to rub down a bit of flat sheet. at a minimum i would prime the hard to get to areas before they go rusty.

i used epoxy 121 to paint my chassis as it is primer and top coat in one. seems to have held up all winter

adrianreeve
20th January 2010, 04:18 PM
I cheated. I left it all as it was, then when it was finished, had it all shot blast and powdercoated!

Cheers

Adrian

RAYLEE29
20th January 2010, 05:06 PM
The trouble with primer is that one of its propertys is its porous
if you leave your chassis for any length of time in just primer it will rust under the primer and you wont see it till its getting bad
if you want it to remain rust free you have to put a top coat on in a reasonable amount of time
or if your using a spray gun add some topcoat to the primer this will stop or minimse the porosity and hopefully stop invisible rusting
Ray:)

bigheppy
20th January 2010, 08:19 PM
I'm about to start building and after buying some steel I intend to paint it with red oxide before even cutting it up. That way it should not rust and by only having a small amount of bare steel around the joint it will be less affected by weld spatter so less work cleaning after welding. :D

HandyAndy
20th January 2010, 08:27 PM
this is just my opinion ......;)

but alot depends on the conditions of the workshop/garage / build area etc to whether you need to paint the chassis "as you build".....

I didn,t & found that cos my garage was nice & dry, no bad moisture / damp etc..... i found that my steel did not rust at all during the chassis making stage.

But i know that Dogwood & Ash built there chassis,s in a more open enviroment so had the need to protect the steel more than myself, so as said... depends on the build area conditions.

or how about using a dehumidifier in the garage during the chassis build??? would this help?

cheers
andy

degmwilliams
20th January 2010, 08:45 PM
I wanted to get my chassis electroplated, has anyone done this before? Its cheap so the cost isnt a problem!

GraemeWebb
20th January 2010, 09:03 PM
I painted the diff and front uprights with Hammerite. Will this be OK do you think? I had some on the shelf and seems OK at the moment but if it will be OK once on the road remains to be seen.

mark
20th January 2010, 09:13 PM
I painted the diff and front uprights with Hammerite. Will this be OK do you think? I had some on the shelf and seems OK at the moment but if it will be OK once on the road remains to be seen.

Should be fine as hammerite works best on a rough previously rusty or still lightly rusted surface like front uprights, the only time its not that great is on a smooth surface with no primer

It just takes ages to dry properly especially in this cold damp weather!

DRCorsa
11th September 2012, 04:48 PM
the difference it its a lot harder to rub down 4 sides in a tight corner than it is to rub down a bit of flat sheet. at a minimum i would prime the hard to get to areas before they go rusty.

i used epoxy 121 to paint my chassis as it is primer and top coat in one. seems to have held up all winter

Do you know if this type of paint is going to adhere to galvanised steel tubes?
Thanks! :)