Steps to deal with rust and loose paint

[MilitaryTrucks]

 

Having never had to do any restoration to a vehicle before yet alone something as large as a truck I have attempted to plan it out hence the steps below. Does this sound the right approach, have I over thought it or missed something? I have a Leyland Daf 4x4 hence the NATO Green as I assume this is the correct colour. I also chose drab as I have never seen a gloss finish on a vehicle like this. All thoughts and suggestions gratefully received as I would rather get it right first time and end up with a job that will last a good number of years.

Step	Bodywork	Action
1	Badly rusted areas	Drill and Wire Twist Knot Cup brush or Rotary wire brush to remove
2	Sound metal areas	Random Orbital Sander with 80 grit paper
3	Lightly hammer around holes to slightly recess the surrounding metal
4	Any rust remaining	Apply rust treatment
5	Fill areas where metal has rusted through	Glass Fibre filler with Glass Fibre Mat behind the hole
6	Sand Filler	Sander plus 400 grit paper
7	Prime twice	Bonda rust primer
8	Under coat	Green Coach Enamel Undercoat
9	Top coat	NATO Green drab Coach Enamel
	Chassis and inside of wheel arches
Steps 2 and 4	There are no holes in the structural steel work.
7	Paint using EPOXY MASTIC type paint

 

Thanks in advance.

Bob

[ruxy]

Twisted knot wire brushes of a good brand are marked with max. rpm , and you need to be near that . You will probably find for the dia. & mounting thread size that the speed is rated for angle grinders - so a drill is quite useless.  The biggest I use is with a Makita 5" angle grinder with back handle for better control. Small - 4" or 4.5 angle grinder for smaller brushes.  For the Makita 5" the brush must be abt. 3.5" to 4" dia.  Normally obtained from Cromwell tools - however press on too much & they shed wires.  Actually - I don't rate them to well, I need to try others for less £ off eBay.

Heavy rust , mechanically cleaning - I sometimes use a needle scaler or a range of cold chisels for heavy scaling & then use carbide tip scrapers , drag scrapers I find effective BUT slowish , but sometimes I use Sandvik engineers type.

Depending on rust  LoL  ,  I find a  RUPES  Electric Palm Sander  (made in Italy & very powerful) with a 40 grit white production paper very effective - then go finer as required.

Undercoat , go with the top-coat makers suggestion.  DBG (Deep Bronze Green)  I normally use a undercoat a shade or two lighter - that is to see where I am spraying TC better, sometimes mixed near to DBG.    For NATO Green a dark grey undercoat may be better.  Undercoats are funny - brown tends to be the suggested for yellow top-coat.

Coach Paint is a bit too oldish, tends to be better with high varnish content.  You will be at maximum  "base matting"  , you may get near to matt , more probably satin - ideal you need a full lusterless.

I would use a  PU (polurathane) reinforced alkyd - known as FLEET ENAMEL , not so common now.   alternatively  a  MACHINERY ENAMEL  (when through dry it is oil and fuel resistant) (Coach Finish is not so good).

Tractol (machinery enamel) and Tekaloid (coach finish)  are now both made by the same firm,  the resins and recipe will be sort of similar.

Whatever - I would keep of paint where the suggested thinners is white spirit, you need something a bit hotter - xylene based (more automotive). Both these paints will easy brush or spray.   I find FLEET good on big vertical surfaces such as caravans , using the proper undercoat.  Dust on top coat , leave 15min to tack then give a double-header or two single passes .  All of these more traditional paints , if you want a gloss , then you should easy get a good 'gloss from the gun' .  For this with cellulose you need a premium primer (supergloss primer) , celle - the secret is in the thinners, the days of flatting & compounding are long gone.  Coach finish (brushing) you can use the even hotter celle thinner in small quantity , otherwise a bit of xylene. Well thinned - white spirit or best turpentine.

 

 

Edited September 7, 2019 by ruxy
spelin

[Tony B]

For rust treatment I would recommend Vactan. It is the stuff the MOD use. Very easy to apply and despite the inital cost is very economical in use. When dry it leaves no sticky residue and can be painted over easily. For chassis etc, I use black roofing paint, again much cheaper than 'Specalist' treatment and just as durable.  Allow the cost for something to treat the inside of box sections as well. 1970's the MOD changed to an Eggshell finish- This is easier to decontaminate the the old matt finish. On military vehicles the purpose of paint is First -~Protection of metal - Second camouflage - THIRD- Cosmetic finish, so perfection is not only unesscary, but you can claim wrong! I have a very understanding - They need to be- local Dulux colour centre. They mix Dulux metal finish , with an egshell additive to colour match samples I take in. It is a also a very durable finish and can be brush or sprayed.

Edited September 8, 2019 by Tony B

[Zero-Five-Two]

8 hours ago, ruxy said:

Twisted knot wire brushes...……………………. I don't rate them too well, I need to try others

 

 

You just need to get the right ones.

These cone shaped ones are awful.  When spinning the wires tend to splay out sideways, giving limited cleaning capabilities, and bits of wire then flick off in all directions.

These Silverline ones are far and away the best.  The extra metal ring holds the wires straight and you can really dig in to heavily rusted bits.  I use 65mm ones, there are bigger available, but they tend to put too much strain on the grinder.

They do lose the occasional wire, so goggles, gloves and a decent pair of coveralls are essential.  Ear defenders and a dust mask are a good idea to. 

[ruxy]

Will try  Silverline brushes , good to have a review as I would never have touched them.   My local Ironmongers that once sold only good brands used by tradesmen of all types  - seems to be now dedicated to Silverline & most of their stuff is £rap.  Although I have had some good service out of  their very £ cheap wood augers that have a hex. shank , however they do just hold in a Stanley brace. 

[Tony B]

If you have a local Toolstation, they are often cheaper than independents, and have better stock in my experience than Screwfix.

[Richard Farrant]

9 hours ago, Zero-Five-Two said:

You just need to get the right ones.

These Silverline ones are far and away the best.  The extra metal ring holds the wires straight and you can really dig in to heavily rusted bits.  I use 65mm ones, there are bigger available, but they tend to put too much strain on the grinder.

 

Hi Rob,

I have used these Silverline twisted wire brushes for some years on everyday work and they are good quality. Secret is not to push hard against the surface, then they work better and last longer. Reasonable price too 👍

regards, Richard

[super6]

What ever brand/make of wheel/brush you use in your angle grinder make sure it's rated speed is higher than the rated speed of the said angle grinder. 

On 9/7/2019 at 10:27 PM, ruxy said:

Twisted knot wire brushes of a good brand are marked with max. rpm , and you need to be near that .

 

[MilitaryTrucks]

Thanks for all the advice. I just need to get on with it now😊

[Chris Hall]

I found in Iraq that heavy rust corrosion is removed exceedingly well with 4oz of PE4. Never failed to leave a nice clean rust free surface.

[Tony B]

12 hours ago, Chris Hall said:

I found in Iraq that heavy rust corrosion is removed exceedingly well with 4oz of PE4. Never failed to leave a nice clean rust free surface.

Even if you had to hunt around in a large area to find it? 😀

Subsequent filling cof the surface can create problems .

Edited September 12, 2019 by Tony B

[MilitaryTrucks]

12 hours ago, Chris Hall said:

I found in Iraq that heavy rust corrosion is removed exceedingly well with 4oz of PE4. Never failed to leave a nice clean rust free surface.

Sounds a bit to kill or cure for me but I will keep it in mind as a last resort😊

[Tony B]

I'd love to know what you think might cure!

Though :

 

Edited September 12, 2019 by Tony B

[eddy8men]

something that i've just started using and been very impressed with is hydrochloric acid aka brick cleaner, you can immerse the part or just cover the surface. works great but only on steel, if ally or brass then just a 30 second dip is all that's needed. good for small parts that would be damaged by more aggressive cleaning. brings up brass shell cases like new

[Buzzweld]

Badl;y Rust areas > Needle gun / Chipping hammer

Sound metal areas>  Blaze rapid strip

Remaining rust use something like Rust-Prime or Rust Encapsulator, Cheaper than the big brands but does the same job.

Key the Rust encapsulator with DA, and then Fill over that. Then rust won't spread underneath.

Forget 7, already done above with simplified process, and having the primer in contact with the metal means you just did primer, rust treatment, and zero rust creep protection in one go.

Coach enamel Checkout paintman and Buzzweld.

Step 7, use WAR underbody superwax. can be colour coded.