DIY Painting Tips

[Langanobob]

Would warming it up a little bit with a hair dryer after poking a hole in it  help the blister to shrink and flatten better when you work it?  Too much heat will  make a mess but carefully warming it to make it a little  more flexible might help.  Disclaimer, no FHE.

That is vinyl, not paint?  Only time I've had a similar problem turned out to be a pinhole leak in the tank and fuel coming from underneath lifted the paint.

[ducpainter]

Would warming it up a little bit with a hair dryer after poking a hole in it  help the blister to shrink and flatten better when you work it?  Too much heat will  make a mess but carefully warming it to make it a little  more flexible might help.  Disclaimer, no FHE.

That is vinyl, not paint?  Only time I've had a similar problem turned out to be a pinhole leak in the tank and fuel coming from underneath lifted the paint.

Heat might help, but if done incorrectly it could also cause more issues than already exist.

The plastic tanks absorb moisture, which could cause this issue, as well as a small air bubble from the factory that expands from exposure to the sun.

Hard tellin'.

[gentlemanjim]

I've had terrific results with SprayMax 2K.  Comes gloss, semi Matte and Matte finishes clears, black and primers.  Gasoline and solvent resistant.  Goes on with a fine mist, no runs or orange peel if your careful. Here's a link to my source: http://www.repaintsupply.com/spraymax-2-part-2k-urethane-aerosol-clear-coat-p3685.html  Eastwood has them too just more pricey.

[LowercaseJake]

OK, I have 2 rare pieces which were hand brushed. A Roadracing tank and DP aluminum cowl.. I need to choose the correct clear coat. I'll either be using Eastwood 2k or having my coater apply a clear powder. Question is this: what gloss level do I choose, matte/semi/or full gloss? First link is to the hand brushed tank, second link is to the look I'm after. I'm thinking a high gloss clear but wanted to confirm. Thanks!

https://photos.app.goo.gl/giVTWdiBFcMafcJS2

https://photos.app.goo.gl/Iqad2joVDZtoZNSv1

Or to put it another way, I want to mimic the look of the BMW RNINET hand brushed tank and tail. :

[Langanobob]

The bare brushed aluminum has a natural sort of matte finish and, in my opinion, it might look plasticky and artificial with a gloss clear coat.  I would lean towards a semi-gloss or even matte.

Maybe you could mimic the brushed aluminum by scuffing up a piece of scrap aluminum with sandpaper and experimenting with rattle can clear coat. 

[ducpainter]

I'd go with satin/semi if you want to match that BMW tank.

If you are talented with a buffer, you could go matte and if it's too dull, polish it to satin. Wouldn't do that if you decide to p/coat it.

Keep in mind whenever you coat bare aluminum, whether liquid or powder, it's all about chemical treatment of the bare aluminum when it comes to longevity of the coating.

[LowercaseJake]

The bare brushed aluminum has a natural sort of matte finish and, in my opinion, it might look plasticky and artificial with a gloss clear coat.  I would lean towards a semi-gloss or even matte.

Maybe you could mimic the brushed aluminum by scuffing up a piece of scrap aluminum with sandpaper and experimenting with rattle can clear coat. 

Funny you mention that, because the factory R9T tanks actually *do* have a plasticky look that I don't entirely hate...In an odd way I like that it both looks painted and like the bare aluminum it actually is. I'm pretty sure the photo I posted above is a tank that's received additional treatment.

"plasticky" OEM BMW alloy tank (perhaps a bit too blingy, which I *don't* want:) https://indianautosblog.com/wp-content/uploads/2016/03/2016-BMW-R-nineT-brushed-aluminium-tank-welding-seam-at-2016-BIMS.jpg

You guys are probably right about a semi/matte gloss level. I think (hope) it'll look good regardless, provided it's applied correctly, simply because what's underneath is legit.

[Langanobob]

...Keep in mind whenever you coat bare aluminum, whether liquid or powder, it's all about chemical treatment of the bare aluminum when it comes to longevity of the coating.

I was wondering about that.  Is a chemical treatment going to change the appearance of the bare aluminum?  Like make it dull and etched looking?

[LowercaseJake]

I was wondering about that.  Is a chemical treatment going to change the appearance of the bare aluminum?  Like make it dull and etched looking?

Same. I'd planned on using the Pre Paint Prep sold by Eastwood, which seems to be some sort of solvent based. As it is I occasionally use it to wipe down the tank and it quickly makes the unsightly oxidation and smudging disappear (for a few days at least.)    DP are you talking about something along those lines (making sure the surface is clean as can be), or actually etching/media blasting the tank somehow?

[ducpainter]

I was wondering about that.  Is a chemical treatment going to change the appearance of the bare aluminum?  Like make it dull and etched looking?

They make products now that aren't supposed to alter the appearance.

I never had the opportunity to experiment with any, and never did find a good source.

[ducpainter]

Same. I'd planned on using the Pre Paint Prep sold by Eastwood, which seems to be some sort of solvent based. As it is I occasionally use it to wipe down the tank and it quickly makes the unsightly oxidation and smudging disappear (for a few days at least.)    DP are you talking about something along those lines (making sure the surface is clean as can be), or actually etching/media blasting the tank somehow?

I'm talking about an actual etch/conversion coating. We used to use Alodyne for aluminum, and Magnadyne for magnesium, but those both are yellow, and contain chromium.

Turns out it's still what's used. Parts need to be clean before use.

Try this...  http://www.chemical-supermarket.com/Henkel-Alodine-1500-Clear-Chromate-Conversion-Coating-p541.html

No FHE.

[Langanobob]

Not much experience painting bare aluminum but I once painted a small bare galvanized steel shop building without using the proper prep.  The paint peeled off in short order.

I think that any chemical treatment is going to affect the appearance in not a good way.  I'm also thinking that a brushed aluminum tank is rough enough and has enough tooth from the paints point of view so that the paint will physically stick to the untreated rough surface.  If it was my tank I'd go ahead and clean it real good and then clear coat it without any chemical prep.  It's not like it's a car where it's a huge job  to redo it if it fails. 

Might try one of the BMW forums at advrider and other places, they might know how BMW clear coats their aluminum tanks or have some experience repairing and refinishing them.

There is also a resin product called Sharkhide that might work as an alternative to clear coating.  No FHE with this either:

http://www.eastwood.com/sharkhide-aluminum-protectant-quart.html

[ducpainter]

I'm not worried about adhesion on brushed aluminum. I'm worried about corrosion occurring beneath the clear, either from atmospheric conditions before you get the coating on, remember aluminum oxidizes in air, or from the chemicals in the clear themselves.

Do what you want. You will anyway.

[LowercaseJake]

I'm not worried about adhesion on brushed aluminum. I'm worried about corrosion occurring beneath the clear, either from atmospheric conditions before you get the coating on, remember aluminum oxidizes in air, or from the chemicals in the clear themselves.

Do what you want. You will anyway.

I definitely appreciate your expert advice, DP. Let's hope my powder coater did what needed to be done.

Here's the results of a high gloss powder over hand brushed cowl. This look was inspired by BMW's zillion dollar R9T aluminum tanks and cowls.

https://photos.app.goo.gl/qRFPB1tPiMDBdgfB3

https://photos.app.goo.gl/Jblnag4GieWI73ta2

https://photos.app.goo.gl/tS2NjzA1hKyYo5HX2

https://photos.app.goo.gl/27ytonpiBwY0HegT2

I'm not tech savvy enough to quite understand why my shareable, public, Google Photos links don't work with this boards image tags. All the logic I can imagine says it should work.

[ducpainter]

Google photos is problematic. I can't figure it out either.

I suspect they don't want the server traffic of hot links so they make it necessary to actually click the link.