Dealing with rusty panels - Surface processing

[rolyberkin]

Hi

Has anyone ever used SPL to deal with rusty panels? Or has anyone ever tried DIY electrolysis to deal with rust? I have just purchased an original bootlid and am looking at ways to deal with paint removal and eradication of rust particularly in the seams.

SPL have quoted me £200 to dip and then electrophoretic coat the panel which doesn't seem that bad if it stops the thing rusting again? Or should I just use elbow grease and over the counter products to treat the rust?

Views on a postcard please...............   

 

 

[Graham C]

Hello

Considering the rarity of the panel then it makes sense to give it the best treatment possible. If the rust is deep then you may have a panel coming back with holes. If it was me I would rub it down by hand and wire brush on a drill and go from there. From the pictures it does look to be surface rust but this could result in pin holes, but these can be filled with weld.

Graham

[Badwolf]

I agree with Graham.

Bilthamber products get an excellant write up in numerous places. I have got some of their de-ox gel and Hydrate 80 but not tried it yet. Karl (Bordfunker) has used another brand which he appears to have had good success with. No doubt he will share his experiences in due course. There are, of course, numerous 'home treatments' which have been used with various amounts of success. The only way to totally eradicate anything but surface rust is to replace the metal which you don't want to do.

[thescrapman]

You could make up a bath of citric acid or better phosphoric acid ( milk stone remover) and then etch primevafterwards.

[Unkel Kunkel]

 

Rule No 1.= Rust always turns out to be more extensive than it first appears.

I have tried a few things over the years:

Hydrochloric acid

( still called muriatic acid by some)

Cheapest source - brick cleaner.

Effective. Cheap but nasty .Unpleasant to use.If you use it indoors its  toxic and aggressive acid  vapour  will rust any of your tools within a 2 metre radius within a few hours - and make you cough and your eyes stream.Quickly flash rusts after use.

Oxalic acid.

Poisonous. Effective . Not easily available.

 Citric acid.

Works both as acid and chelating agent.

The cheapest way is to buy food grade citric acid in I kg bags via Ebay. Relatively  non-toxic.

Basis of Turtle Wax immersion rust remover.

Disappointing. BUT... if it is kept warm- around 36-40 C.(a brewing immersion heater is good esp. if tweaked to run a bit hotter) The results can then be  very impressive indeed.

Every few hours, wire brush off the debris and reimurse

The used solution is relatively non-toxic and can be poured away into drain or garden.. The iron citrate  mixture is an effective moss killer on asphalt ( it stains concrete)  After use coat with the metal with phosphoric acid to prevent flash rusting.

Phosphoric acid

Can be expensive ( ie Jenolite).

Milk stone remover cheap but check as not always straight phosphoric acid these days.

Machine Mart Rust Remover is Phosphoric acid.It seems to work as well as Jenolite at a fraction of the cost.

Some lasting protection from the phosphate - use after other treatments to avoid flash rusting.

Coca-Cola contains a tiny amount of phosphoric acid, but don’t waste your time-  it will disappoint as a serious rust remover.

Evaporust - Effective for immersion -but expensive. Probably a chelating agent such as EDTA.Advantages =Easy to use as probably the least  toxic after citric acid.and can re-use  for a few times.

Molasses - a chelating agent -effective but  takes many weeks by which time it smells and looks foul.

Various vinegars -acetic acid.Can be effective - Depends on concentration.

Coatings - Those ones that turn blue  are tannic acid which forms a hard coating of tannate on iron.Can work very well - but only on superficial rust .The coating  has to be well applied.

Rule No. 2 = If in doubt, cut it out.

 

 

[Clive]

I have used electrolysis. Very effective, very easy. Just need a big enough container for the bootlid.

I have used HCl (brick acid) as cheap to do initial cleaning, and bought some 80% phosphoric acid off eBay. 4-8x stronger than stuff sold as rust removers, so I dilute it 4:1. Use a sprayer to coat stuff that I gave cleaned as above, stops flash rusting after. Then use a decent etch primer (acid 8 is good stuff)

[RogerH]

On 17/08/2019 at 11:33, rolyberkin said:

Hi

Has anyone ever used SPL to deal with rusty panels? Or has anyone ever tried DIY electrolysis to deal with rust? I have just purchased an original bootlid and am looking at ways to deal with paint removal and eradication of rust particularly in the seams.

SPL have quoted me £200 to dip and then electrophoretic coat the panel which doesn't seem that bad if it stops the thing rusting again? Or should I just use elbow grease and over the counter products to treat the rust?

Views on a postcard please...............   

 

As the lid has no lap joints or folded edges the SPL treatment would be very good indeed. 

Bilthamber DeOxC is also excellent for rust removal. It gets into grain of the metal and pickles out virtually anything that is rusty.

If you have pin holes consider lead loading (you would only need a spot here are there) rather than welding - you may get distortion if in the middle of a panel.

A decent polyester filler would also work well.

Roger

[Bfg]

.

£200 + VAT ? + the toing n' froming the panel to SPL. would seem a lot to me for such a simple and small panel.   If you're up to the Ipswich area anytime (perhaps to our local club meeting at the Sorrel Horse)  I can give you a jar of phosphoric acid (for free) to take home with you.  NB. phosphoric acid is the key ingredient of Jenolite.  You can then spot-treat the areas of rust and  just d.a. sand where there's good original paint.  That paint, and its key to the steel, has worked well for decades, and in many person's opinion is much better than most modern (nanny-state) paints.  

With any acid treatment - the important part is to neutralise / thoroughly clean all the acid out of the pitting and any overlapped (spot welded) joints ..before sealing that acid in with paint.

Personally I would be fearful of applying heat for lead loading with such a thin panel. I just know it would distort. Araldite however is pretty tough stuff for filling a few pin holes.

Regarding fillers :  Polyester filler is hydroscopic (lets water through) and also shrinks by as much as 5% as it cures ..so is always in tension (which is why it likes to peel off).  Best is to use epoxy filler - It's just as easy to use.   If you can't find it - look to boat supplies.  

Likewise most paints are not waterproof,  so choose your product well.  And perhaps use the £200 for a professional paint job.

.. that's just my opinion like. 

Pete

 

[RogerH]

ooops - scrub Poly Insert  epoxy

 

Roger

[rolyberkin]

Thanks for the replies enough there to keep me busy for a few days!:-)

Just got back from a few days away but found a bottle of deox gel in the garage so had a quick blast with that, think I am going to strip the paint off the top side completely to see what I have and then go from there, I am not in a rush and I am keen to have a go at the electrolysis route so may build a small custom tank first to see what effect that has.

The dark bits which are left are concerning me, may have a quick run over with some of those poly discs to see what effect they have.

[Bfg]

22 minutes ago, rolyberkin said:

The dark bits which are left are concerning me,

And why not just give those areas a second application ?

 

[Unkel Kunkel]

The dark bits are pitted areas that still have rust in them.

I think the active agent here is citric acid ,albeit rather expensive ,with additives to gel  and keep it in place.Effective, pleasant and safe to use.

The answer is  - re - application/ wire brush  and just keep on going   - doing it over and over again, until it looks like grey pitted metal.Then any doubt -do it again.

I tend to then apply  some phosphoric acid  say Jenolite, then dry it to give a dark grey protective phosphate layer - and repeat this a few times  too.Dry it with a moderate hot air gun. Any trace -do it again.

 It is time consuming - but persistence does pay in the end with this job.

 - You’ll get there!

[Badwolf]

A restorer I spoke to suggested (this was actually for the liquid) building a dam around deeply rusted bits with blu-tack, flooding the area with solution and leaving it for several days gently scraping at the rust occasionally to aid penetration. I must stress that I have not tried this yet but it sounded a good plan for smaller areas. As I think you have done, covering the solution with cling film prevents everything from drying out and aids the chemical reaction

[SpitFire6]

Phosphoric acid. Better if you can dip it.

Hydrochloric acid if you want to dissolve the whole piece.

Citric acid or cola if you want to prevent nail polish damage.

Dremmel & caffeine or similar stimulant to mechanically remove it. Followed by Phosphoric acid.

Cheers,

Iain.

 

[Bordfunker]

I’ve had good results with strip discs in a power drill to get the paint and the rust off the surface, followed by a coat of Rustbuster’s FE123 to neutralise any rust in the pores of the metal.

I then apply either an etch primer, quickly followed by a coat of Rustbuster’s epoxy mastic, or just a coat of the latter.

Karl