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View Full Version : Preparing/painting your frame (guide/ toutorial)


KieranM
01-29-2010, 04:00 PM
Just thought i would add a helpful thread about painting and preparing frames for painting. I am talking about using spray cans and spray guns as we do not all have the services of powder coating at hand .

anyway, if you have just finished your build and are stripping down to paint these few tips and hints might come in handy.

-Firstly, you will have welded up your frame at the start of your build and there is a high chance that dirt,metal shavings and oil have gotten around your welds, also rust may have started to set in if you have left it for a while. You should get a quality electric/battery hand drill with a wire brush and get into all the welds and clear out all the rust and shavings. For the more awkward welds a small steel brush may be handier. Next go over all your frame with nice 200-400 grade sandpaper to remove all the surface rust. Get your air compressor and blow down your frame to remove removed rust and the like,get your paintbrush and clear out the welds.


-Next you will need to get yourself a nice tin of rustproofing paint (this is the most important thing to do, without the rustproofing your at nothing. Buy a quality brand for the obvious reasons). Put a base coat on and get into all the welds, put a generous amount on. After your first coat of rust proofing, leave your frame to dry for 24hrs or 48hrs if you can (leave your frame in place where dust will not be risen for the best finish). Then give it a second coat, same as first.

-After shes fully dried its time to move onto main paint. I highly recommend using a air compressor paint gun for accurate spray, but if you dont have one the spray cans do grand. When spraying stand back and avoid spraying the one spot, wave the sprayer /can around giving each part of the frame equal amounts of paint. To avoid dripping make sure you have a paint brush in hand and be constanly watching for drips. After first coat leave her dry for abot 24hrs-48hrs. Then give her a second coat. In most cases a second coat is sufficent enough but if its not feel free to give it a third.(between each coat get yourself a high grade sandpaper and go over it to get out any blemishes)

- After you are satisfied with your paint job its time to move to the finish. Get yourself a fine lot of lacquer. This is harder to spray as it in transparent so be careful. Give a spray all around your frame. Leave it to Dry for about 24hrs. The Lacquer is optional as a shiny finish is not needed on an offroad vehicle.

There you have your guide to preparing a frame for spraying and spraying it.

TIPS.
- Do not clean with wd40..ect as this can get into your welds and leak out during spraying and cause the paint to blotch.

- Use a quality paint as some cheaper brands react with the rust proofing.

-If using a heat gun to speed up drying ( not something i am a fan of) be careful to avoid heating the one spot as it will bubble and look bad.

- Always spray at room temp, never in anything lower than 10 Celsius.

- keep away from dust.



Hope this Helps a few people.

Russ2251
01-29-2010, 05:16 PM
go over all your frame with nice 200-400 grade sandpaper to remove all the surface rust.I would recommend this stuff as it saves a lot of time and labor:
Klean-Strip phosphoric prep & etch (http://www.wmbarr.com/product.aspx?catid=32&prodid=81)

chetcpo
03-01-2010, 07:49 PM
I would recommend this stuff as it saves a lot of time and labor:
Klean-Strip phosphoric prep & etch (http://www.wmbarr.com/product.aspx?catid=32&prodid=81)
+1 This is a crucial and often overlooked step.
Structural steel bought at the steel yards is often hot rolled "oil pickled" steel. As such it's really black and grimy with this nasty used motor oil like stuff on it. You can clean it off with solvent and swear your metal is as clean as possible but the oil residue remnants will compromise your paint job if you skip this step. POR brand metal kleen and metal etch or the Kean strip mentioned above will both work to eat away the oil residue and "etch" the surface of the metal to allow the paint to stick incredibly well.

I've used this stuff and then laid on a good proofing paint like POR-15 or Rust Bullet (even better since it is UV resistant and requires no top coat) and the result is very similar to a good powdercoating. Likewise I've skipped this step at times and seen my uber expensive $60+ a quart paint peel off at the first scratch.

As for rust removal, I wouldn't worry too much about it. Rust is a natural "etch" in the metal and will actually increase the adhesion of your paint and won't cause more corrosion when properly treated. The phosphoric acid compounds actually convert the rust to a hard phosphate compound and stop the rust process in it's tracks. The result is a very good surface for holding paint.

Hendersonjk
03-07-2010, 10:27 AM
it says to lay abunch of layers of lacquer over your paint. I`m sure you probably ment clean but thought I`d point out that lacquer over enamel doesnt work the lacquer is too strong and the enamel will wrinkle and peel up like its beeing stripped. enael over lacquer is okay as long as it is full dried but not vise versa. but I have to say that lacquer makes a great primer its easy to spray and sand and dries quick. Por 15 is some insanely hard and thick stuff my hat is off to it.

Hybrid
04-19-2010, 11:10 AM
You can just spray some flat black primer on there and call it a day =D especially for offroad carts.