clear coat

[jkokura]

My question about that self leveling: How does it go around the corners of the box? do you pour it on the top, and then it drips fairly evenly over all four sides? How thick is it on the corners/edges? And how would you remove it if there was a mistake?

Jacob

[G. Hoffman]

I know this has been beat to death but I need a clear consensus of what is the hardest most durable clear coat to put on pedals... I tried finger nail polish... ah no, Krylon acrylic clear... nice clear but not really durable..., clear epoxy... wouldnt self level, lacquer... again wouldnt self level.... does anyone have a secret out there... I want a hard durable clear coat. The epoxy and lacquer looked like water droplets on the pedal, not a bad effect if thats what your going for....

and yeah I've searched it and have read them all...

I just want a hey this works, I know because I did it.

First, "hard" and "durable" are two very different things.  A harder finish will tend to be brittler, and will be more prone to most types of damage (chipping, scratches, etc.).  

Second, the one most important secret to ANY finish work is sanding/good prep work.  Its always a temptation to skimp on prep work so you can get to the part where you get to put on your pretty colors or fancy graphics.  

Don't give in to that temptation.  

Ideally, before you start any kind of finish work you surface should be so nice that you don't want to put any finish on it.  If you can find any imperfections in the surface, you have work to do.  My main material is wood, but metal is no different when it comes to the importance of prep work.  Sand each grit until you have a perfect surface.  Don't skip grits.  Don't ever say, "that's good enough."  When it comes to surface prep, the only thing that is "good enough" is perfect.  Trust me, you can do it.  Its boring, but you can do it.

Also, when it comes to spray finishes, though I know the internet always tells people to spray light coats, I've got to tell you that no professional finisher would ever do so.  Ever.  It wastes time (because you have to spray too many coats), a dry coat of finish will never level properly, and will never really flow together right.  Also, from the point of view of a professional, you want to get as much finish on as possible without sags, so you can spray fewer coats, which saves both time and money!

But even if you are not a professional, if you want things to look good, you MUST spray a wet coat - while avoiding sags - or your finish just won't look right.  On my guitars (yeah, they're wood, but after the first coat of finish the material underneath doesn't matter, I'm spraying finish on finish), I spray "double coats," which is to say, I spray one (barely) wet coat, and then as soon as I finish the first coat, I immediately spray a second (barely) wet coat.  This allows the finish to flow out better, and is less likely to sag than just spraying one heavier coat.  Success spraying a flat wet coat, however, comes down to technique and experience.  Until you get the experience, you just have to deal with sanding out the sags (try strip sanding - you use a small strip of sand paper, hold it down with one finger directly on the sag, and pull with your other hand - it makes getting rid of sags a lot easier), and be careful not to sand through.  Oh, and the other part of spraying a flat wet coat?  Good surface prep.  Scratches can cause sags, as they break the surface tension.  

So, I guess what I'm saying is the problem is likely not the finish material you are using, but your technique.  The one thing which is certain, though, is that the better your surface prep, the better your final finish.

Epoxy is definitely the hardest clear coat, short of exotic aircraft paint or something. I've used this stuff:

Most epoxies don't actually dry all that hard.  Finishing type epoxy (bar top finish epoxy, or certain marine epoxies) will certainly be durable, but is usually pretty soft, relatively speaking. When thin enough, they can seem hard, but don't be fooled - they aren't particularly.  They do self level pretty well, at the expensive of excessive thickness (which looks cheesy to me - kind of like the crap Fender was doing in the seventies).

Actually, the hardest finish I can think of off the top of my head is Shellac, which when properly dry in a thin film, is crystal hard, but it is also rather brittle and not particularly durable.  (Don't ever spill your beer near it!)


Sorry about the length - I'm kind of a wordy guy.


Gabriel

[davent]

Hello,
Haven't built anything in quite awhile but for my last pedals used the waterbased sanding sealer and lacquer sold by Stewart Macdonald.  Took a ridiculous number of coats (and wet sanding back) over the course of many days to build up a level finish but the results i think were worth it. Being water based there's no noxious fumes so can spray inside year round without driving us all outside.

For dust protection i just pop the enclosure into an old shoebox 'til it's time for the next coat. Like the heating pad idea, have to give that a try, basement can get pretty cool in the winter.

Temperature is definitely a factor, even outdoor house paints wants at least 10°C (50F) before using.

For those in a hurry, Beavis audio in the instructions for finishing a box in a day, suggest using a waterbased polyurethane as the finish of choice.  http://www.beavisaudio.com/techpages/boxinaday.html

Take care,
dave

[23]

will give envirotex a try soon..... I prep my boxes well but tend to like some small imperfections for some reason or another, I usually do the duplicolor transparent paints with a design buffed into the metal, ya know, faux wood grain, swirls, sunburst type things... I just need a good durable, glossy coat to go on top thats better than Krylon acrylic clear.... I took screws and a piece of wood to make a platform to hold the pedal up and use a pyrex dish to cover for dust.

[glops]

Thanks for you input, Gabriel.   For some reason, I was under the impression that cured epoxy was hard as a rock.  Nice to know that may not be so.

I think epoxy looked appealing because of the cloudscapes' boxes.  I'm sure the finish may not be great for every graphic but I think it looks nice
in a jpg format.  Would like to see an epoxied box in person....

[Taylor]

Well, I guess isn't hard. It dries to a plastic-y consistency. But it is durable, in the sense that you can stomp on it a lot and the finish won't come off.

[G. Hoffman]

Well, I guess isn't hard. It dries to a plastic-y consistency.

Exactly the word for it - plastic-y.  Its not soft like taffy or anything, it just isn't as hard as most really fine finishes.

Now, if I were looking for a clear coat that could be done easily at home while achieving really fine results, I'd at least try Stew-Mac's waterborne lacquers, as has already been mentioned.  I might want to spray it over a layer of shellac, since I don't know its adhesion properties with metals.  It  would take a bit longer, but in the end, if you take your time with surface prep, sand appropriately between coats, and wet sand and polish at the end, it could blow peoples minds.  But then, I'm just trying to get my head around Slade's etching techniques, and don't have any real desire to try a clear coat on pedals, since I do enough of that on guitars!


Gabriel

[23]

but wouldnt you want to clear an etched pedal as well? Ive never done etching as Im really a colour person, wouldnt mind trying it tho. A clear would keep it from collecting finger prints right? or do you not highly polish them enough to worry about finger tip oil? I think I would leave little imperfections in them for a more industrial look... shrug

[davent]

I've used Conservators Wax^® on bare aluminum amp chassis' and it does a good job of preventing finger marks from showing.   I bought mine here, little tin should last a life time. http://www.leevalley.com/wood/page.aspx?c=2&p=20090&cat=1,190,42950

dave

[glops]

Hey Gabriel,

Do you recommend wet sanding shellac between stages, as well?  I assume the answer is yes.  I guess I will have to experiment.  I did one
pedal, that I ended up sanding off, with shellac but didn't care for the results.  It was an amber shellac, but I assume there is a clear shellac?

For shellac, would it be advisable to use a spray vs. brushed on?

Thx in advance!

[rjl]

My question about that self leveling: How does it go around the corners of the box? do you pour it on the top, and then it drips fairly evenly over all four sides? How thick is it on the corners/edges? And how would you remove it if there was a mistake?

It self-levels amazingly... I just poured it across the top of the box & the bottom panel and it started leveling immediately and pouring over the sides. Any place that wasn't covered just took another tiny pour and a careful brushing with one of those wood-handled foam brushes (use a clean one). The corners were covered perfectly. If not, just pour a tiny bit more over the corner in question -- so long as it's still wet / within the first 10 minutes or so after mixing-- and watch it level out.

Thickness on corners/edges looks uniform with the rest of the box. Very smooth, glass-like appearance all around. It seems a little thicker at the edges along the bottom of the box, but nothing too bad...

As for making a mistake, the instructions are good at outlining possible less-than-favorable scenarios, how you got there, and how to remedy it. A lot of their fixes involve sanding and re-pouring. Or removing w/acetone.

I just tried this on a box this weekend, and it is quite amazing.

A few tips I learned from my first time using it:

1. Have the box raised unless you want to cement it to whatever surface its sitting on. I took a small board and drove 8 screws into it (2 groups of 4 - one for the box, the other for the lid/bottom panel). Make sure the screws are level all around. I then made a small foil tray underneath it all to catch any excess ooze, and threw a bunch of newspaper underneath it all.

2. if you're using the 16oz. bottles, probably 1/4 from each bottle (as it's mixed to a 1:1 ratio) is sufficient to cover a small box.

3. Have a small pin handy. The expoy will flow into any drilled holes, and sometimes gather in them (it's pretty viscous stuff). If that happens, just stick the pin into the clogged hole, and run it in circles around the circumference of the hole. Keep going until the stuff pours clear through. I forget at what point I did this, but it was within the first hour or so.

4. You'll see bubbles in the epoxy while mixing. Don't worry about them. They'll disappear when you pour.

5. The bubbles that the directions warn you about seem to be pretty rare, and a little heat will get rid of them. Just catch 'em while it's still liquid / as they appear. I held a lighter near the one that I had, and it just popped, and filled itself back in with epoxy, as it was still liquid.

[rjl]

One more tip - this stuff is gonna ooze into the holes in a pre-drilled enclosure. Even after using the pin-scraping method above to clear out the majority of the goo, you'd benefit from carefully scraping the insides of any holes with a knife, preferably sharp and preferably from the inside of the enclosure, to clear the inner edges of the holes of any Envirotex, else your jacks, pots and LEDs may not fit.

[therecordingart]

Where did you get these knobs?

[Taylor]

http://www.smallbearelec.com/Detail.bok?no=727

[therecordingart]

What did you use to mount the standoffs in the enclosure? JB Weld? Any notes on positioning them correctly?

[head_spaz]

I used JB weld and it worked quite well. I couldn't break them loose with all the thumb pressure I could muster.
Alignment is the easiest part.

Tips...
1.) Use the tip of a needle file to scratch up the surface inside the enclosure where the standoffs are to be glued.
2.) Attach the standoffs to your PCB with screws and snug 'em up tight.
3.) Use some coarse sandpaper to scratch up the sides of each standoff.... but only on the ends.
4.) Mix up some JB Weld (thoroughly!!!) and place a blob of spooey on the end of each standoff - using a toothpick to work some glue into the threads.
5.) Then add a thick blobbette of excess goo around the sides of each standoff.
6.) Then position the whole assembly into the enclosure... and secure it with weight, clamps, or whatever, until the JB Weld cures.

The excess JB Weld, from step 5, will flow down around the standoffs and glue them to the enclosure perfectly. It forms a nice filet at the joint that would make a welder proud.

And that be do it.
Justa lik'a dowwwn towwwn.

[therecordingart]

I used JB weld and it worked quite well. I couldn't break them loose with all the thumb pressure I could muster.
Alignment is the easiest part.

Tips...
1.) Use the tip of a needle file to scratch up the surface inside the enclosure where the standoffs are to be glued.
2.) Attach the standoffs to your PCB with screws and snug 'em up tight.
3.) Use some coarse sandpaper to scratch up the sides of each standoff.... but only on the ends.
4.) Mix up some JB Weld (thoroughly!!!) and place a blob of spooey on the end of each standoff - using a toothpick to work some glue into the threads.
5.) Then add a thick blobbette of excess goo around the sides of each standoff.
6.) Then position the whole assembly into the enclosure... and secure it with weight, clamps, or whatever, until the JB Weld cures.

The excess JB Weld, from step 5, will flow down around the standoffs and glue them to the enclosure perfectly. It forms a nice filet at the joint that would make a welder proud.

And that be do it.
Justa lik'a dowwwn towwwn.

Awesome! Thank you for the info. That is a tidy build!

[therecordingart]

http://www.smallbearelec.com/Detail.bok?no=727

Do you know if these are push on or do they have a set screw. I need small diameter knobs with a set screw because I have round shaft pots.

[Taylor]

Pretty sure all of Small Bear's knobs are made to fit 1/4" solid shafts, and have a set screw.

[Hides-His-Eyes]

I've seen people say "clear nail varnish- nah" but not really why: does it just not self level very well or is there something more to it?