Rustbullet Automotive - Review

[SLR_dave]

There have been a few queries about this product over the past year or so. I have used it and I said a while back that I would start a thread for it. I saw some members on the site were looking at rust proofing options on the forum today so I finally got this thread up.
I am still locating some photos, so this first post will get some edits as they arrive.

I looked into this stuff over a long time before I decided to use it. It’s a bit of a tale but, I reckon its worth telling, it really is quite different paint, (if it is paint at all, its almost like a metalised glue!)

Some tips on application and my experience of using it will come in another post on this thread, cause its just too long otherwise.

I first heard about this product about seven years ago from a mate of mine who had seen it online. I had major rust issues in areas of my first van and he suggested I check their website. What I found looked impressive, particularly their video showing the product comparison tests.
I was of course, not straight away convinced and I did a fair amount of research over a number of years into it, and other products before I finally chose it as a rust proofing coat.
Here is the Rust Bullet video I saw years ago showing the sample product tests. (Three weeks of saltwater spray in humidity followed by two weeks of seawater immersion).

http://www.rustbullet.com/testing.asp?id=24 (saltwater spray test)

http://www.rustbullet.com/testing.asp?id=25 (seawater immersion test)


Rust Bullet Automotive can be overcoated with ‘just about’ any other type of paint, - but the initial overcoating of the Rust Bullet (which can be just one coat of sandable primer matching your chosen paint for instance) needs to happen within 48 hours of applying the two required coats of Rust Bullet to do it without sanding or you have to “scuff up” the surface as instructed – with 100-120 grit.. yep...that rough. Otherwise the overcoat wont stick. Its better I think to get the base coat of your top coat system on within the 48 hour window with no sanding. (I note, btw that this 48 hour window is now sometimes described as 52 hours… I think this is happening as the product research continues).

Rust Bullet requires two coats to work (I ended up doing three and a bit due to stuff ups) and there are drying time requirements (min and max) for doing this.

Rust Bullet Automotive also does not actually require a topcoat if you are happy with the interesting silver finish it gives – its sort of a dull metallic silver (good for a non collectible vehicle maybe).
Interestingly, (and attractively to me as the panel work on my car will have to be done in sections), Rust Bullet is claimed by the manufacturer to display some very resilient qualities when exposed to bending of the metal (Mandrel Test) and to heat (I couldn’t find the spec at this stage but I have seen it out there, from memory, it was above 1000 Celsius).

http://www.rustbullet.com/testing.asp?id=27 (Mandrel Bend Test )
http://www.rustbullet.com/testing.asp?id=28 (Impact resistance test)
http://www.rustbullet.com/testing.asp?id=26 (Taber Abrasion Test)

In terms of welding, Rust Bullet needs to be removed from the joining surfaces prior to welding or it may weaken the weld, and it burns toxic, its temperature resistance is very high for paint, the amount of area you may want to redress and re-coat around a weld will depend on the job of course.

Another attractive thing about Rust Bullet is that its application guidelines provide (and dealers I spoke to assured me) that sections of the rust treatment which may be damaged due to panel work after application can simply be re-coated, providing the surfaces are prepped properly – I would imagine some overlap to the previously existing coat though would be a help as well.

But is what they claim true?

So the story starts, I started hunting around and talking to people, I found all the leading rust proofing treatments are fairly pricey, some people recommended PO15 or KBS, and reckoned one or the other were the best avail, but at this time, none of those I spoke to had even heard of Rust Bullet, so .. I had to wonder how informed they were, so I went looking for an Australian distributor to have a chat.

As mentioned, this was around seven years ago and at the time the product was pretty new and had no established distribution in Australia (that has now changed). There were only two dealers on the East coast.

The closest to me was in Nowra so I gave them a call. Turned out it was a service station! (Caltex I think- can’t remember), but the guy explained it had worked for him so well he decided to become a sales outlet. He didn’t stock it, but could get it for customers on order from the US. He told me that it was amazing stuff, did everything it said in the online video, and he “had never seen paint like it”.

He told me that two years prior, he had used it to paint a completely rusted out almost worthless trailer, that had been sitting on the edge of the ocean open to salt spray for more than a decade, the trailer was rusted through in parts, but he wanted to use it once, for just one job, and it needed to pass rego, he hadn’t prepped it at all, just decided to see if this paint he’d heard of would actually stick to rusty steel and work as claimed, and that it did, and came up looking great. AND… (this is what got me)… that more than two years on the trailer had remained sitting on a hill, open to the ocean in the salty wind, and still had not a sign of any rust coming through the paint at all… AND THEN…. he had gone to replace the taillights ( I suppose that means he was still using it) and had to take a file to it to fit them. He told me it took four strokes of a bastard file before it even marked the paint!!!

He went on to say that Rust Bullet just gets harder and harder as it sets. He hadn’t overcoated the Rust Bullet and explained (as everyone I spoke to afterward does) that you don’t need to if you want a silver like finish, it is a one stop material, but will take almost any overcoating with proper adherence to the instructions.

Anyway, due to the timeline of my projects I had a bit of time before I had to decide, I’d held the rusty sections temporarily with Wattyl Kill Rust and… I had to decide on if it was worth saving that van at that stage.. it has some probs! (yep there’ll be a thread on my first van at some stage when I get the pics sorted – I’ve lost some atm).

Over a period of about three or four years, I observed, dropping in to the Rust Bullet website (then there was only one) there were various minor developments, notably, minor changes and additions to the application guides, (these seem to be continuing to develop at this time ) also the addition of the ‘blackshell’ automotive chassis product.

Rust Bullet is available for different applications, their basic product is for structures like buildings, or bridges, or steel infrastructure, even concrete, or, (for instance) restoring rusty farm structures like a big packing shed roof. The Automotive product has been around for at least seven years now and (as far as I understand it) is designed so it can be applied thinner.

If you look at the original (US) website you will find videos on application and heaps of instruction and information, these are replicated and variously added to on the Australian and UK sites.

One of the early videos show a mustang being sprayed with Rust Bullet with very little rust prep comparatively. This video takes a while to play through, but its worth watching to the end I think if you re considering using the product, it also shows use of the (optional) 'blackshell' chassis product.

http://www.rustbullet.com/assets/res...Automotive.flv

That said it would obviously be better not to permanently leave such unprepped areas like as done on that Mustang! On my vehicles, everything that will be permanent I prepped to shiny shiny steel, as you would for any decent paint job and then applied the Rust Bullet.

However, I have some sections that will later be cut out, and so they got minimal prep and this is where I wish I had not lost my photos - I’m still looking!

The final result I got is actually exactly as described by the company. Its good stuff, but its unusual in the way you apply it, I'll put up a post on application issues I had next. Heres some pics that give an idea how it goes on, and one showing it overcoated with 4 coats of Dulon Acrylic sandable primer and Dulon Acrylic top coats. Next post - Application issues!!



April May Early June 186.jpg010920121010.jpgpic 120.jpg

[SLR_dave]

APPLICATION AND PREP GOOD AND BAD ISSUES:

It took a bit more effort than I expected, and wasn't without hitches. But the rust bullets surface, and its adherence is excellent, like glue (almost).

It’s a really different surface coating. It does have the appearance some observers in various online forums have made, that is, a smooth over coating with a slightly metal sheen to it, almost as if it’s been sprayed with ‘new metal’, or has been galvanized, but smoothly and evenly.

The paint pulls remarkably well. Despite the tough seeming coating, it hasn't changed the shape, lines or form of the vehicle at all, it sprays a bit thick, almost like spray filler, but it thins itself somehow (or it did for me). I got a smooth even coating of only a few “mils” (not millimeters - “mils” as in dtf microns) – I cant measure it of course, but I’m sure its above the minimum thickness required by the Rust Bullet guidelines and lines of the the car look clean as (in all sections that don't need future panel work anyway that is).

Like all paint, its all in the prep – and with Rust Bullet that prep is a bit different than with some other paint systems.

Rust Bullet likes to go over steel or solid paint ‘roughed up’ with 100-120 grit, when I say steel, either clean shiny steel or can be rusty steel, but without any non rust bullet system approved chemical coating or residue.

It may not adhere well if surface treatments like deoxidine, or other ‘rust converters’ have been used anywhere and left on the vehicle. If you look at a clean steel surface that has been treated with de-oxidine, you will see rainbow colours in it - this is a coating that sticks to the steel.

At the time I used it Rust Bullet was not approved to go over this, the chemical adherence was unknown, it may be approved (or not) by now however – talk to your Rust Bullet dealer. You can sand deoxindine residue off before applying Rust Bullet if you have put it on however.

You don’t need these products with Rust Bullet anyway, they have their own product for difficult areas called “Metal Blast”. Rust Bullet likes bare shiny steel, or solidly painted surfaces scuffed up with 100-120 grit. But, stopping flash rusting on bare shiny steel overnight can be very difficult.

Rustbullets “Metal blast” – like deoxidine and K&H rustconverter, needs to be washed off with water. So you put water on your shiny steel…… note the golden yellow… flash rusting. Rub back with wet and dry… again! And again and so on.
However, I have to say that Rust Bullets Metal Blast product works a lot better, easier and faster than de-oxidine or K&H rust converter. You are supposed to rinse off any white residue after using Metal Blast of course, but then, the area you are gonna paint has to be totally dry before applying the Rust Bullet paint, this can be very tricky for some areas, with channels and seams, if you leave it to dry overnight, how can you see if its flash rusted before you paint?

However, Rust Bullet has some tolerance to go over a bit of residue of the Rust Bullet “metal blast” product (which is largely phosphoric acid I think).

The Australian Rust Bullet technician I spoke to approved this level of Metal blast residue for one small area of the car I could not otherwise get clean and dry if I had to rinse it off (I sanded the residue off this area instead). The pics below show how Metal blast can get difficult areas clean into the corners (the brown colour in the pics below isn't rust, its just brown paint), - one of many areas I was keen on getting clean and rust free for this car is this interior channel along the roof join on both sides, usually, this would have been pretty tricky, but metal blast did it well. The far right pic shows the opposite channel on the other side of the car after the same prep, given a day to dry and then two coats of Rust Bullet. (I have lost some of my pics, so couldn't show the exact same area, but the prep and the results are the same on both sides of the car).

mETAL BLAST USE FOR REVEIW reduced.jpg Metal Blast channel.jpg Opposite channel after paint.jpg

I found looking at their online information and talking to the Australian Rust Bullet dealer helped me get it right.

As for soda blasting… urrrgh - the issues are worse I think when using Rust Bullet. The issues people can have with soda blasting (I discovered after doing it) are that the soda residue can, sometimes, be very hard to remove. It depends what brand soda medium the blaster is using, and establishing this is really imprecise. Many soda blast websites will tell you (and I think mostly genuinely innocently) that the medium is just plain bi-carb soda, but it is not. It depends where they source it, but it always contains some form of lubricant, (usually a silicone) to get it to flow through the blasting gun. In my case, in some sections of the car this stuck on so hard it would not abrade off, it made melted smears of ‘stuff’ this was eventually removed with citric acid, but… it wasn’t real easy. I don’t know if other paints would have tolerated this surface well in a rustproofing fashion, quite probably not, but I was advised with Rust Bullet to remove it all, which I did, so in the end, the prep was all shiny steel, – apart from the sections that will be cut out later (some pics of those areas still to come in next post).

Side and gutter.jpg Front on steel.jpg Some panels.jpg

Now, that all said, I did have some trouble with the initial application of Rust Bullet. I tried to use a spray gun with a 1.8 mil nozzle (that is within the recommendations of 1.7 to 2.0) and it clogged up and carried on, and I did not get good coverage, it was a mammoth and toxic session and it wasted good paint and Xylene, I only just got the first coat on so thin, enough to just coat all steel to stop it flash rusting overnight, but too thin for the first decent coat – it was just a mist coat in some areas. I contacted the distributor and they said, it had to be a 2 mill nozzle. I got the nozzle and had to scuff up the first coat to make the next one stick because I was outside the 48 hour window (not too hard took about 2 and a half hours) – that said, the paint amazed me, even sprayed like that it stuck hard, and had finished quite well.

Then with the two mil nozzle it went on really really nicely, but I ran out of paint after one and a half coats!!! I needed two, so, I had to order more, which took about three days before it arrived.

When I opened the protective packaging around the new tin I was surprised to see that it was swollen up, as if it was about to explode – the bottom of the tin was puffed out so the tin could not sit flat. I went ahead anyway! I opened it gingerly, (wearing full protective gear of course) and it did not explode, but the paint seemed thicker than the previous tin. This time again, I had real issues with it, it would not flow nicely through the gun as it did on my second session, it blocked and carried on. I called the distributor.

They were aware of the problem, they told me that sometimes, in transport, the paint can thicken in air transport due to changing temperatures in air transit. A thinner had just been developed. I knew the thinner was a brand new product as well because I had seen it for the first time just a week prior on a UK Rust Bullet site, and wondered about it. The distributor had only on shipment of thinner and sent me a (very) small bottle (free of charge), you can only thin it by 5% though anyway or the paint may not work. (I think they calculated how much paint I had, and sent me no more than would otherwise have been too much).

Anyway the paint really is pretty thick when its right anyway... it needs to be like drinking yogurt, so I got the thinner, mixed it in stages, and it went on well, so in the end I got three and a half coats, two and a half good, and one just below acceptable.

Two coats is the required standard, the first coat reacts with any rust to inhibit it but doesn’t seal it, the second coat is the sealant, and surface tension dress coat.

Now it sounds like a nightmare, (and it was a bit – but it’ll be easier with van number 2 now I’m more used to the paint) but, the resulting finish for a rust proofing coat seems very tough, and I reckon its gonna work very well.

Front with door and nose cone after RB.jpg passenger side after RB.jpg Door with RB cropped.jpg

[SLR_dave]

How it went in specialised problem areas:

Rust Bullet Automotive seems to handle areas where corrosion has caused mild pitting really effectively. It also has a slight filling effect, its not total, but its good, way better than I expected, I feel fairly confident that there are not tiny surface undulations in the rust coating that moisture might find under the base primer coat.

With most paints, for decent prep, you have to make sure you get all the black out of the tiny pits, before going with a base coat, if you don't get it all, its pretty much gonna rust/continue corroding at some stage under the new paint. Looking at that Mustang video for instance, Rust Bullet doesn't have this requirement for its 'ten year guarantee', however, I wanted my job to last as long as possible so I prepped to full spec for normal paint, (the blasting helped).

Ignoring the sections I will need to replace, this van has only pitted corrosion in one area; in the cowl under the windscreen (this is lucky considering some of the rest of the car). The two pics below are the best I could recover of after the prep and after Rust Bullet. Also, the second pic shows damage to the far passenger side of the cowl. I haven't done anything to this section at this stage except remove the bog that was there and paint it, that work is for later on. It will be interesting to see at that stage how the rust bullet goes thinking of the impact and mandrel tests linked to in post number one.

Pitted cowl sectio prepped.jpg Pitted cowl section after RB.jpg

Another thing that is pretty awesome is the way it handles rough surfaces. Here's some pics of the interior - in these pics the prep is minimal, it wasn't rusting that I could see, the odd bit of surface here and there. I just went over the existing paint with a cup brush on an angle grinder (which I decided has to be rougher than the 100-120 grit spec for going over existing paint) and sprayed the rust bullet on. This surface was previously several layers of different paints, and the brown that is evident is partly paint, mostly glue that probably held carpet stuck to the walls at some stage (it looked like old vinyl/carpet glue to me) and so it was pretty lumpy, I had no idea how I was going to prep this section for making good paint stick and look flat, it seemed like hours of work, but I decided to just see if the Rust Bullet would clean it up as promised, so I saved the last of the Rust Bullet as a test to try it out. Result was excellent! The paint covered really well on one coat, has no bleed through, even over the glue residue, - this on its own is pretty useful!!

Interior quick prep.jpg results of first RB painting session after curing 011.jpg results of first RB painting session interior.jpg

Now... the really bad sections.

As mentioned at the top of this thread this car had some fairly serious rust/problem sections, and because of the way things worked out, I had to rustproof and base paint it before doing the body work and final coats. When I got the car, the rear quarter sections both had poorly executed patch welding done at some stage in its life, (on the drivers side the area is large). This had been bogged over, and on the drivers side had completely rusted out again near the wheel. Because these areas will need to be completely cut out and redone again in the short to medium future, I didn't spend too much time on the prep, but gave them the same coating of rust bullet as the rest of the car. I wanted to just hold any continuing rusting in any of the body till I get the cash, parts, and plan for completing the job properly. (This is where it will be interesting to see how Rust Bullet goes with welding at some stage). Anyway when it came to primer and top coat, I decided on the spur to give these sections a go over anyway, albeit only a few light coats, just to make it look a bit more of a going concern.

The pics below show the drivers side rear quarter just before it was painted with Rust bullet and then given a base coat of Dulon acrylic primer around 18 months ago. The rest of the primer surfacer coats and the top colour coat went on about 12 months ago. The pics with the colour coat were taken this week (as again, I lost the pics of just the rust bullet, which is a shame because the top coat hides it, and after 12 months garaged, you'd expect most paints to still look like this). Its not enough of a test yet to know, and these sections will get cut out before too long, but, if you look into the rusted out section, the pics do show in close up how Rust Bullet goes over flaking corrosion. (Btw the angle grinder cuts are to show me where the minimum amount of rust I need to cut out is - because I expected that the Rust Bullet would hide this after painting, - which it would have.)

April May Early June 132.jpg 18 months after RB 12 months after top coat.jpg Close up.jpg

And finally, really ridiculous sections!!

Below are pics of the upper tailgate - its completely rusted out around the window, top and bottom. This would have been almost a chuck out... but its original Sandman, but last on my fix list right now, so I prepped it as well as I could, and the rusted out sections I decided, well, its heritage value.... as long as, (if I do decide to put it temporarily back on the car), it doesn't spread rust to the rest of the body. I gave it three good coats of Rust Bullet wondering why I was wasting the paint.

The effect again was the same, the rusted out sections are not as pliable as they had been, the paint is tough stuff it seems. So then I briefly primed it and very quickly top coated it (using the very last of the Dulon I had, maybe two coats - the pics show where the paint ran out). I've actually ended up with a rough, but serviceable upper tailgate...for the moment... if I keep an eye on it..., this was not something I expected to even bother attempting to paint, but would it now be acceptable to put back on the car without it spreading oxidisation around.. I gotta wonder... I sorta think so yes, and it'll be a good wall hanger for a long time now at least.

090420101914.jpg 090420101915.jpg 090420101916.jpg 090420101917.jpg 090420101918.jpg Dec Jan Feb 2013 2014 001.jpg
Dec Jan Feb 2013 2014 004.jpg Dec Jan Feb 2013 2014 006.jpg Dec Jan Feb 2013 2014 010.jpg

SOME DOT POINT ISSUES AND TIPS:

An opened tin cant stay exposed to air, you have to place glad wrap on the surface of the remaining pant and then fully seal the lid if it beyond the specified time limits.

It cant be sprayed in humidity above 90% - (although it can be sprayed in temps as low as 0 degrees C ! – useful in winter! - remember overcoat paint requirements though)

You can’t taint it with any other paint.

You need a decent water filter on your airline, getting water in the paint will muck it up – although at the end of my third coat my gun started dripping water off the nozzle from condensation, some drops fell on the surface being sprayed, they actually didn’t mix with the paint, they just sat on the top of it and evaporated (I am talking maybe three drops over a whole car here though and it already had two coats on it).

Once I got over its issues, - which took a while… and of course you haven’t got much time to work when it mucks up cause you cant thin it I found it actually sprays pretty nicely off the gun, and it dries so much better.

You do need the recommended type of spray gun or it will stuff up. I used gravity fed HVLP eventually with a 2 mil nozzle as recommended, – I wouldn’t attempt it again with 1.7 even though the instructions say you can – I had trouble at first with even with the 2 mil nozzle – it is thick stuff (and my initial coat was really not satisfactory to me, too thin in parts, with a few spits and splotches, and this took up expensive paint and I had to order more, – but, I ended up in the end with really good coatings.)

And a pretty decent compressor – and a heap of xylene for cleaning everything between coats, its, 4 hours plus to dry for one coat and the paint will ruin the gun in that time if not really thoroughly cleaned.
And you need to spray the moisture out of the gun with xylene first.

You need a respirator of course and full body covering including gloves and safety goggles/ or a full or half face mask.

It is fussy. Very. You need to follow the instructions to the letter, this is harder than it initially seems. (see links below)

Its solvent is Xylene.

It sticks to everything .
(It sticks very well to skin, and doesn’t come off for up to two weeks - maybe more!)

If you get it on you you have to use Xylene to get it off, Xylene dries the skin really intensly, and stings, and can burn, and you may absorb it. Xylene is really bad to inadvertently inhale, a leaky respirator will easily give you chemical pneumonia and a plethora of general side effects and potentially real immediate problems. But then again, so will Tolulene (or other thinners).

Its very easy to end up working in a rich Xylene vapour atmosphere if you are in a garage even with the doors open and the product over thickens, (see above #2) – and of course, venting Xylene to atmosphere is illegal in most states and territories (just like Tolulene).

I have read people who had bad probs, like it just falls off, peels in sections etc, all I can say is prep!! - This paint only likes what is advised, don’t use De-oxidine for instance, doesn’t like it, wants to go on clean steel, or roughed up solid paint.

It was particularly difficult I found, to use it after soda blasting.

It must not be mixed by shaking, or it spoils the product,

It is not supposed to be thinned (although they do now sell a thinner).

Further Links:
http://www.rustbullet.com/uploads/RBAPPLGUIDE711.pdf
http://www.rustbullet.com/faqs_print.asp?id=4

[thatotherguy]

Great thread thanks for posting,not sure if rust bullet is the same but por 15 is not uv stable and will break down if left exposed to sunlight

[SLR_dave]

not sure if rust bullet is the same but por 15 is not uv stable and will break down if left exposed to sunlight

Cheers! Thats something I didnt know. Think of the potential hassle if you had to move the car during the job!

Rustbullet is fully UV stable, it can be a usd as a topcoat. I have had a section of another job with RB on it out in the sun all this sumer, its fine.

[Big Rob]

A comprehensive description mate!

It sounds like a lot of hard work, but with a great result if you do it right.

Another product that is virtually unknown but is top quality, like Nulon when 1st released.

[Duc1991]

Dave
This is a great thread and very interesting and informative. Thanks for taking the time to post. I have retread it about 3 times already.

[SLR_dave]

Thanks Rob and Duc, theres still some pics to come, which give a better idea of the prep I did and the finish acheived on the majority of the car, but perhaps more interestingly, on those areas which have to be cut out or replaced and so the prep was minimal... these are, I think , worth a thought. Anyway I had trouble uploading pics for some reason, I'll try again today.

[SLR_dave]

Dunno if the rusty tailgate pics add to this or not... lol!! I've lost my pics that just showed the rust bullet, still, it gives an idea.

Also (and finally for me for this thread) a member also made a comment recently about prepping the gutters. Here's how I did mine to prep them for Rust Bullet;

Firstly the car had been blasted, but this had not brought the gutters and seams up perfectly. I went over the insides of the gutters with a wire wheel on a drill. The result got most of the paint out, but was still not quite right, I had bits of old cracked seam sealant in the tops of the gutters, and some remnants of paint. There was also old seam sealant left under the gutters (between the gutter and the body looking up from underneath).

I was concerned about the condition of the steel under the seam sealant, so I picked it out top and bottom with a cheap pick (a bit like a very fine scribe) got in a set of four for about 5 bucks. This it turned out was worth doing (pics below). (I later removed the seam sealant with the same pick from the main body seam as well on both sides).

Removing Seam Sealant 1.jpg Removing seam salant 2.jpg Rust under seam sealant.jpg


Then I went over the gutters again with a wire wheel, and eventually, that not getting all of the the inside edge, cleaned it up with a small sanding block (just used a piece of quad) - heres the results.

Passenger side gutter 2.JPG Passenger side gutter.jpg Drivers side gutter.jpg

This left two issues to address, one was simply replacing the seam sealant afterward (there is a thread on this elsewhere) but mostly, now I had removed all the factory paint, how to coat the inside outer edge of the gutters with rustbullet. (Clearly it was going to be difficult to spray here and get reliable cover without messing up the paint on the roof or other places - the gun just didn't look like it would fit, and there'd be paint mess everywhere trying)

gutter with arrow.jpg

It seemed better to mask the roof and brush paint two coats of Rust Bullet into the gutter before spraying the rest of the car - I used two cheap, small/medium sized artists brush to do this (80 cents each) - bent one into a right angle at its ferrule - this let me coat the inside edge with accuracy (pic to come one day maybe if I still have the brush, but its a pretty simple idea - doesn't really need a pic).... although, I did find a dentists mirror and a torch useful to check the coating on the inside lip of that gutter afterward was really useful.

Gutter masked for rutproofing with RB.jpg

Btw I should thank other members who helped me realise the importance of replacing the seam sealant, and helped me with tips and advice about doing this, there is a good thread about doing this on this site in paint and panel, it would be optimum I think to put the seam sealant back on directly after the Rust Bullet, mine actually went on after the Dulon Acrylic sandable primer overcoat, but I personally cant see there's much difference. As long as its back in there over compatible paint, but I think directly over the Rust Bullet would be better (havent tried it yet).

Seam Sealant completed.jpg