Best Spray-On Finish for Pedals?

[Ice-9]

I have always found the best for good smoothe results is to use cellulose auto touch up paint. It's not the toughest of coverings but gives a pro looking finish. MXR have used the stuff since they began and there pedals when old still look good. As R.G. mentioned it is in the prep and primer that makes a big difference in quality.

[The French connection]

That looks just like what I have done, but I still have the thick, drippy edges problem.

Here are some pics of a Small Clone Chorus I did a while back.  Note that this one has a light plate; red for power and blue for effect on.  You can see the drips along the bottom edge of the box, especially in the close ups.

If I could solve that problem this would be my favorite finish.  Hard as a rock.

I got the feeling you put to much resin and wipe just once or twice...Sometimes i use the micro-torches to heat rapidly around the drops to permit wiping more of the overflow. But you got to be careful to not overheat the resin locally.

[KazooMan]

I probably did use too much resin, but I do keep wiping for quite a while.

I know what you mean about overheating the resin.  You can get a nice toasty brown color on a white pedal if you over do it.

[vigilante397]

I have always found the best for good smoothe results is to use cellulose auto touch up paint. It's not the toughest of coverings but gives a pro looking finish. MXR have used the stuff since they began and there pedals when old still look good. As R.G. mentioned it is in the prep and primer that makes a big difference in quality.

Is there a particular brand you've found that works well? Where do you buy it and how much does it typically cost?

[davent]

That looks just like what I have done, but I still have the thick, drippy edges problem.

Could that not be reworked with a fine file and then wet sanded to smooth it all out?

dave

[vigilante397]

Another remarkably general question (new to this):

Assuming the box has been prepared properly (cleaned, sanded, etc), how many coats of primer, how many coats of paint, and how many coats of clear coat? Is there a right/wrong answer to that, or should it just be as many as I feel it takes to get it looking the way I want?

[R.G.]

Talk to the custom car and custom guitar painters. For a truly amazing finish, the answer is "more coats and work than you're willing to do".

The really good finishes, like on high-end grand pianos and unlimited-cost autos have dozens of coats of paint and clear coating, each one hand rubbed to flat before the next coat.

Do it till you get tired or until you think it's good enough - and I find that my "good enough" varies downward with the amount of work I do. 

[vigilante397]

Talk to the custom car and custom guitar painters. For a truly amazing finish, the answer is "more coats and work than you're willing to do".

The really good finishes, like on high-end grand pianos and unlimited-cost autos have dozens of coats of paint and clear coating, each one hand rubbed to flat before the next coat.

Do it till you get tired or until you think it's good enough - and I find that my "good enough" varies downward with the amount of work I do.  

Could not have asked for a better answer I think I'm about ready to have another go at this, which is good because my next shipment from tayda gets here tomorrow ^_^

Also, The French connection, I decided I'm going to try out your Envirotex lacquer. You were right about eBay, I've got an 8 oz bottle heading my way, definitely going to try it out!

[bwanasonic]

Talk to the custom car and custom guitar painters. For a truly amazing finish, the answer is "more coats and work than you're willing to do".

The really good finishes, like on high-end grand pianos and unlimited-cost autos have dozens of coats of paint and clear coating, each one hand rubbed to flat before the next coat.

Do it till you get tired or until you think it's good enough - and I find that my "good enough" varies downward with the amount of work I do. 

I found the same to be true back when I read hobby magazines about scale modeling. The finishes that I drooled over were pretty much beyond my attention span as a young modeler, and involved many layers of spraying and sanding.

[vigilante397]

Talk to the custom car and custom guitar painters. For a truly amazing finish, the answer is "more coats and work than you're willing to do".

The really good finishes, like on high-end grand pianos and unlimited-cost autos have dozens of coats of paint and clear coating, each one hand rubbed to flat before the next coat.

Do it till you get tired or until you think it's good enough - and I find that my "good enough" varies downward with the amount of work I do. 

I found the same to be true back when I read hobby magazines about scale modeling. The finishes that I drooled over were pretty much beyond my attention span as a young modeler, and involved many layers of spraying and sanding.

That actually brings up another question I had and forgot to ask earlier. Should I be sanding between coats of paint on my boxes or just baking? Sand then bake? Bake then sand? Is sanding an important part here? New at this 

[alanp]

As far as I know I'm the only weirdo who does this, but clear nailpolish works for me. Hard as nails, no faffing about with ovens, one coat does the trick.

[m-theory]

In a previous life, I sold auto refinish products, and have done scores of pedals over the past 6-8 years, so I've got some insight into this that I'd like to share, fwiw.  This will get lengthy, and will probably include some pretty basic, "boring" information that won't be of use to some, but might be to others.  Painting is an extremely complex process, and finish failures can be the result of a failure at any point along the way in the process.  I'm going to provide some information to hopefully help those who're new to this, that will hopefully help them prevent some common failures, and produce great results routinely.  I don't profess to know everything about everything, including this process, but I do have a significant amount of experience in this world, so I want to share at least some of what I've gained from that.  It's still an extremely complex, highly involved process with a tremendous amount of variables that can, and often do, interfere with our ultimate goal of "pretty," but at least if we understand some basics, we have SOME control over the end results, even in less-than-perfect spraying conditions, such as what most of us live with. 

First, nothing that comes in a spray can, regardless of the brand name, is "professional."  It's all a compromise of some sort, because of the simple fact that you cannot control reduction ratios, solvent flash rates, atomization and spray pressure.  You get whatever comes out of the can.  There ARE differences in the actual product inside, but it's not nearly as vastly different as one might think.

What we get in spray cans is either lacquer, synthetic enamel, or acrylic enamel (or, in the case of some clear coats, polyurethane), all of which can produce fine results, but none of which should be confused with "professional" product, not because of the resins and solvents involved with each, but because of the fact that we have zero control over reduction rates, solvent flash times, or pressure/atomization at the point of release.  What we get is what the manufacturer gives us.  Thankfully, for our purposes, what the manufacturers provide is product that's intended to be applied over very small surface areas, which means that it dries pretty quickly, yet can still provide a pretty decent, smooth finish, if applied correctly.

With spray cans, we have to be aware of what products we're using, in order to have an idea as to how those products spray, lay down, and dry, in our current spraying conditions.  Temperate, humidity, and the particular resins and solvents that make up the particular product we're spraying, have dramatic affect on dry time and finish appearance.  We can determine the basic composition of these products by reading the labels on the cans.  Rustoleum is synthetic, or alkyd enamel.  It is the slowest drying, and therefore has the potential for the smoothest finish, but also holds great potential for grabbing onto foreign objects and also re-coat lifting issues, such as lifting/wrinkling. 

Lacquer dries the fastest, and acrylic would be next in line.  All are fully capable of producing results that are excellent, disastrous, or anywhere in between, depending on how they're applied and what the substrate consists of.  As with any refinish project, the end result can only be as good as what's underneath, so if you don't bother to do proper prep work, don't be shocked when the results are less than stellar. 

Beyond the goal of a smooth, clean finish that only results from proper prep and spray work, you want excellent adhesion throughout.  On cast aluminum, this is a rather monumental task at times.  Due to the nature of the substrate itself, as well as whatever mold release resins are utilized to ensure easy removal of the cast product from the mold when formed, it can be difficult to nearly impossible to obtain excellent adhesion to cast aluminum.  The only SURE way to obtain it is with a TRUE acid-etch primer, either of the "wash" variety or the "self-etch" variety.   Regardless of what the can may say, aerosol "self-etch" primers aren't the same. 

True self-etch primers are comprised of two parts, one being a zinc-rich product with build film characteristics and the other consisting of an acid, that literally eats into the metal.  I had a customer eons ago who refinished a boat trailer that he'd painted 10-12 years prior.  He sandblasted the entire thing before starting, and was able to remove all topcoat and primer, EXCEPT the self-etch primer that he'd started with.  It's impressive stuff.  What we get in a spray can is NOT the same.  That said, it is better than most spray can primers, for bare cast aluminum, so I do recommend using it, even though it's not anywhere near auto refinish-level quality product. 

The primer that I've found that has the best adhesion overall is rustoleum auto primer.  It takes a LONG time to dry, so expect to leave it overnight, but once it's dry, it's easily sandable, and sands to a VERY smooth surface, ready for whatever topcoat you want to apply.  Yeah, it's "best practice" to keep products chemically aligned, so, theoretically, you should use either alkyd, lacquer, or acrylic throughout the entire finish process, BUT, we're not painting cars or anything that's going to be exposed to the elements, other than the typical elements that a typical guitar effect pedal is exposed to, so the bottom line is that what we're looking for is a smooth finish (usually) and extremely strong adhesion, in order to fend off nicks and scratches as best as possible.  I've found that the rustoleum primer provides outstanding adhesion at the base, and that carries throughout the rest of the finish, at least in my experience.  Personally, I don't care for Rustoleum products in general.  They're rock bottom, cheapo products overall, because of the chemistry involved in making them, and that particular chemistry doesn't necessarily work all that well for pedals, imo.  They're simply not awesome overall, BUT, again, we can produce results that are either awesome, awful, or anything in between with spray cans, regardless of what's brand name and chemistry involved.  I've just found that the rustoleum auto primer sticks really well...better than some that I've tried, and adhesion is SO important that I've just chosen to stay with what I've found works for me. 

Pay attention to flash times, dry times, and especially, re-coat times.  I've not personally had any luck with baking finishes in an oven, fwiw.  I have much better luck air drying.  Whenever I've baked, I've wound up with lifting problems when re-coating.  When applying non-catalyzed products, it's important to realize that there is never a "cure" process involved.  "Curing" refers to the chemical process in which a catalyzed (Hardened) paint product literally transforms, chemically, from a liquid to a hard, "plastic" surface that is impenetrable.  You can literally take thinner and wash off any paint surface that's not catalyzed, decades after the paint has been applied.  It will ALWAYS be "re-wettable," whereas a catalyzed paint product will NEVER be re-wettable, once it's cured.  It literally becomes something chemically different than it was when sprayed, and will not be affected by solvents after it's cured.  What we use in a spray can will never become that.  It will ALWAYS be re-wettable, which means that ANY solvent that touches the finish has the potential to re-wet and remove it. 

With this in mind, it's critically important to know the re-coat times involved with each product that we spray.  Usually, you'll find that there's a "window" during which re-coating can be done reasonably safely, and beyond which, one has to wait for 7-10 days in order to re-coat.  This is where oven baking can cause problems.  What we're waiting for is for the solvents within the given products to evaporate from underneath the "skin."  Generally, we'll have some amount of hours during which we can reasonably safely re-coat.  Beyond that period, the top "skin" has formed to the point where whatever solvents remain underneath are trapped, and will literally take days to evaporate.  If you apply product during that period, you risk re-wetting the solvents underneath, causing them to force their way to the surface, which, by this time has formed a hard outer layer.  The result is a wrinkling effect, which can lead to lifting and peeling later on.  Wrinkling alone can be a cool effect, but the potential for lifting and peeling comes with it, so be aware of that. 

If you apply additional coats before that magic window closes, or after the 7-10 day period, you'll dramatically limit the potential for wrinkling/lifting/peeling.  In my world, that means that, once I have a dry, sanded, cleaned undercoat, I generally will work through all of my top-coating until it's complete.  The products that I usually use (duplicolor, fwiw) tend to flash very quickly and dry well enough to reapply within 10-20 minute, so even complex finishes involving numerous layers can be completed within a couple of hours.  At that point, I let it sit, until I'm confident that most solvents have evaporated, the finish is fully dry to touch, and doesn't mar from fingernail pressure.  Then, I clear it. 

I'm personally not at all a fan of spray-on, lacquer, acrylic, or polyurethane clear coat.  They all suck, imo.  None of them retain full gloss potential after flash off, all of them require many, many coats in order to obtain ample protection and gloss, and none of them come close to matching what the two-part epoxy clears can accomplish with a simple, single application.  The trick to using these (envirotex is one) is to recognize that there is FAR more mil thickness upon initial application than we need.  Look at your car's finish closely, and you'll see that the actual paint film and clear coat is extremely thin.  What the 2-part clears offer us is the ability to lay down, with virtually no effort, as much as 50 mils of clear thickness.  This is roughly 12 times what we need for protection, and will lead to all sorts of problems, including the globs along the bottom edges, clogging of screw holes underneath, as well as eventual yellowing, cracking, and peeling. 

Again, I'll say that NONE of what we use is truly "professional," in the sense that, there is no auto refinisher with any integrity who would stake his reputation on spray cans and hardware-store clear coats.  We can only do the best that we can do, with the products that we have on hand, and, since most of us don't have access to a body shop and the extremely costly, hazardous catalyzed products that they use on a daily basis, we rely upon what the local hardware store can provide, and, if used properly, what we have access to can actually produce some pretty stellar, remarkably durable results.  In my experience, the 2-part epoxy clears offer the best gloss and highest level of protection that we can reasonably obtain at home, but there are some tricks to using it, and the first is to realize that we don't need anywhere near the 50 mils of thickness that it provides us upon pouring. 

First, read the instructions carefully.  This stuff needs to be mixed PRECISELY 1:1 in order to cure properly, and it also needs to be THOROUGHLY mixed prior to pouring.  Two minutes of vigorous stirring is what I give.  You want it to go from a very thick viscosity to a notably thinner variation, with tiny bubble infused throughout the entire liquid.  Two minutes of vigorous stirring usually produces this.  Just be aware that the 1:1 ratio AND COMPLETE mixing is critical with this stuff, in order to get a full, proper cure.  You cannot shortcut this.

I like to use those tin cake pans that you can buy for a few dollars at the grocery store...the ones that come with a clear plastic lid, so you can peer at it from time to time without having to pop the lid.  Once it's cleared, the less you expose it to the air around the room, the less chance it'll attract and trap air boogers/dirt/dust/hair.  Cut a piece of pegboard to fig inside the bottom of the cake pan, and attach long bolts from underneath, to serve as stands to place the pedal box parts on.  The clear is very messy, and stays fluid for a LONG time, so it drips.  You want to have a way for that drippage to fall away cleanly, in order to minimize cleanup after it's dry, so the fewer points of contact on the box, the better. 

Once the clear is fully mixed and stirred, pour it onto the top of the box.  Use a plastic spoon to lay it all around the edges and corners.  Make sure that it fully covers every part of the box.  You can lay it on as thick as you want and let it drip at will.  Once you have it fully covered, either get a blow dryer out on full throttle or take some deep breaths and blow across it, HARD.  You not only want to remove the tiny air bubbles from the clear, but you also want to literally get rid of MOST of what you've poured out.  You only need a few mils of thickness in order to provide ample protection, and the more you have over that amount, the less desirable. 

During the first hour or so, you can literally pick the box us and use your hands and fingers to wipe off excess, if you want, because the clear will completely re-flow to a glass-like surface when let to sit.  I've used the back of the spoon along the lower edge, to remove excess, but I've also used my fingers with equal success.  When it's "young," the clear will wipe off fairly easily with paper towel, and remaining clear washes off hands easily in the early stages, so don't be afraid to touch it early on.  It's non-toxic.  Just be careful where you work, because this stuff does cure like concrete.  Chances are, your significant other won't appreciate seeing globs of hardened clear on the counter or kitchen table the next day!  (more experience speaking here!)

I'm still trying to find a way to keep the clear from invading the screw holes at the bottom of the box.  I tried toothpicks, but that turned out a failure, when the toothpicks simply snapped off as I tried to remove them.  I'm sure that there's a size of metal dowel or something that could be inserted prior to clearing, that could be easily removed after cure, but I haven't found it yet.  Suggestions would be openly and graciously accepted!  The fact is, as great as this clear is in so many ways, the cleanup effort after cure can be truly exasperating, which is why I stress minimizing the amount of clear left on the box.  Get rid of as much of it as you possibly can, while it's still wet and flowing. 

Ok, so now you've got the pedal cleared, it's looking gorgeous, and you've removed all excess clear, including along the bottom of the box.  You'll see it accumulate here for at least an hour after you apply, so go back every 10 minutes or so at first, to remove that accumulation.  The more you remove while it's wet, the less you have to remove when it's cured, and trust me, it's a LOT easier to remove while wet. 

Now, let's say that we're at the point where you're confident that it's as perfect as it can get.  The clear coat has laid down like glass across the entire box, and you've removed all excess from the bottom edge.  There are no serious boogers that you can see.  Now, cover it, and leave it covered.  There is nothing further that you can do that will make things better.  Anything and everything you do, from about 45-60 minutes after pour, on, will make things worse.  At this point, the clear has become gummy, and will no longer flow freely, so whatever you do now, will remain.  That little piece of hair that you just noticed?  Leave it.  It's too late now to do anything about it, other than make matters worse.  Chances are, when it's cured, if you leave it be now, that tiny hair won't be so terrible that you have to remove it.  And, if you DO feel that it has to be removed, it can be MUCH easier removed once the clear is cured, by wet sanding with 1200-1500 grit paper, then re-applying clear. 

That's it, really.  If you finish your clear coat work by say 10pm, you'll be able to CAREFULLY handle the box by 8am or so, and should be able to start cleanup by that evening.  The clear will remain somewhat soft for about 2-3 days, so be aware of that.  If you can wait for 2 days to start clean up and assembly, that's best, because you CAN leave permanent fingerprints, if you hit it too soon. 

For cleaning excess, cured clear, I use a straight edge razor, a scraper, and, for the screw holes, a small screwdriver.  For the holes, you don't necessarily HAVE to pry the clear out of the holes.  You can also push it inside the hole, as it's drilled far deeper than the screws seat anyway.  Again, the best solution there would be to prevent the clear from getting into the holes in the first place, though I've yet to uncover the magic prevention cure for that dilemma.  Obviously, take great care in removing the excess, cured clear with sharp edged utensils.  The clear cures extremely hard, and is not at all easy to remove.  If you take great care to eliminate excess while it's still wet, you shouldn't have too much difficulty in removing whatever excess remains after cure. 

Again, this whole finish "thing" is a very complex, highly involved, multi-step process.  It's important that we recognize that stepping in, so that we can apply the appropriate level of attention to detail all along the way, in order to minimize failures and maximize successes, to whatever level of "perfection" we hope to attain.  Fwiw, I've come to really appreciate the powder coated finishes that have come to the market over the past few years.  I still like to apply my own art work touches, and still apply the clear coat, but it's hard to beat the durability and smooth finish that powder coating provides, and, when you consider the cost of materials and the enormous PITA involved with spraying primer and color coats ourselves, it seems like a heck of a bargain. 

Be safe with this stuff.  None of what we spray is good for us, so take appropriate precautions.  Take care, pay attention to detail, be aware of the particular characteristics of what you're working with, try to develop a pattern that works for you, and have fun!  I know that I do! 

[KazooMan]

I haven't tried to file and sand down the drippy edge.  It would probably work, but believe me, this stuff is hard!  I don't see the drips when the pedal is on the floor, so I just try not to think about it

[bluebunny]

@m-theory: thanks for such a compelling read!  Really useful.

[duck_arse]

wowee, that's a real painting primer.

are there any different/special rules for paint on steel?

[davent]

Epic post m-theory, thanks for taking the time to put that together!!!

As far as the screw holes go, would wrapping a screw with plumbers Teflon tape and screwing it in prevent the hole filling and still be easily screwed back out once the clear has hardened?

I switched to an airbrush and artists waterborne acrylics a number of years ago to get away from the noxiuos spray can fumes and also to reduce the clutter, can get the paint in much smaller quantities as opposed to the rattle can products.

dave

[vigilante397]

As far as I know I'm the only weirdo who does this, but clear nailpolish works for me. Hard as nails, no faffing about with ovens, one coat does the trick.

I must have skipped over this as I was reading everything else. Alanp do you have any pictures? If it works well and is easy to use I'll definitely give it a shot Nail polish seems like a reasonable option, has anyone else tried it?

[bwanasonic]

There was a recent post asking about uses for vaseline, and I'm wondering if it couldn't be used to protect the screw holes during resin coating?

[PRR]

> vaseline, .. to protect the screw holes during resin coating?

I was thinking candle wax.

Either way, you must NOT!! get any on surfaces that paint must stick to.

[Morocotopo]

m-theory, outstanding explanation. Thanks.

I used some time ago what I believe is the equivalent to Envirotex, a gooey clear that came with a catalyzer, here the product it´s called "Vidrio Líquido" (liquid glass), I guess it´s an epoxy.

Question. To solve the dripping problem, is there a solvent that can be used to thin the stuff? Thinner maybe? Or something specific for epoxies? I also once used water based two part epoxy clear, that was easily thinned with, well, water.