PPCB Acid Rain Fuzz for my SCHMORG

[dawson]

:: TRIGGER WARNING ::
RUSSIAN MUFF KNOBS USED


I couldn't help but be curious about this fuzz the moment I saw it- it's a bit mysterious.

"PedalPCB Original Fuzz" is the only description you get on the store page- I figured it's got to be pretty good, coming from somebody who's traced and laid out a billion other fuzz pedals.. I would always just scroll past it since I have more fuzz pedals than I use already, but due to constant praise and recommendation of this circuit on the forum, I decided to build it out, along with a couple other highly recommended circuits (I build in batches.)

Here it is:

^You can see where I re-worked a couple resistors. I seated a 100k & a 10k in the wrong spots and had to swap them.. that's what I get for populating PCB's in the middle of the night.

It sounds much better now than it did before the circuit was assembled correctly and is a pretty cool-sounding fuzz with a wide range of tones. I look forward to trying it with different guitars, because although I can tell that it's got a lot of potential, it's really not jiving too great with my main instrument right now (Reverend Descent Baritone.)
The Acid Rain just cleans up too quick for it! I plugged in and was just getting boost/light overdrive tones and thinking "WTF?" until I realized I was cutting the signal with the BASS CONTOUR knob on the guitar.. in other words, I can't effectively EQ the guitar without losing that sweet, sweet gain. *As I'm writing this, I'm thinking, "maybe hit it with a pre-boost or a little pre-drive?" I'll report back after I give that a try, but as of now, the PPCB Scarab will remain the only fuzz in the SCHMORG.

The graphic was made using the vector tools in PhotoShop and etched with ferrich chloride, as always.
I know there are some knob purists around here who may block my profile after seeing these SmallBear reissue knobs on a non-Big Muff circuit.. but I bought a lot of them in a panic when SB was "closing," and they look really, really cool.
It's got a red 8mm LED sitting on top of 2 lime green 3mm LED's:

If you're wondering WTF is wrong with this guy who thinks it's okay to build upside-down pedals with no pants on, this thread may answer a question or two:
SCHMORG

 

[Bio77]

Great build! That LED is idea is pretty sweet.

I picked one of these up recently but haven't built it, yet. I would have guessed from the name that this was related to the Raincoat, which I believe is Bugg's original inspired by a Muff. So, maybe you're okay with the knobs?!?

 

[fig]

SCHMORG!

Acid Rain = Flesh-melting droplets of tone.

 

[Diynot]

No shame in some righteous knobs! I too have a stash of them acquired from SB. Love the etching. Do you go in and back fill with anything or just leave it raw after the etch? Also digging the all blue caps and resistors.

 

[peccary]

Do you heat your ferric chloride before etching? I need to take another crack at it as I've only really tried it twice and didn't like my results and have a big bottle of it eyeballing me every time I go in to the garage.

Edit: I forgot to mention how bad ass this build is, but to be fair I am just sick of telling you how awesome you are

 

[Harry Klippton]

Do you heat your ferric chloride before etching? I need to take another crack at it as I've only really tried it twice and didn't like my results and have a big bottle of it eyeballing me every time I go in to the garage.

Pretty sure you not supposed to get it in your eyes brah

 

[dawson]

Great build! That LED is idea is pretty sweet.

I picked one of these up recently but haven't built it, yet. I would have guessed from the name that this was related to the Raincoat, which I believe is Bugg's original inspired by a Muff. So, maybe you're okay with the knobs?!?

Thanks! I'm totally okay with the knobs, but there were a fair number of memes deployed in opposition of the idea so I thought I'd goof in remembrance.
You know, I thought I read someplace that it's inspired by a Muff as well, but I couldn't recover the thread that mentioned it, so that's what aided my knob choice here. After playing with it for awhile though, it doesn't feel like a Muff to me at all.. but that only means that Bugg's ideal "Muff" is a bit different from my ideal "Muff," and there isn't anything wrong with that!
Glad you dig the LED's

SCHMORG!

Acid Rain = Flesh-melting droplets of tone.

You know it- glad to finally join the Caustic Chemical Club!

No shame in some righteous knobs! I too have a stash of them acquired from SB. Love the etching. Do you go in and back fill with anything or just leave it raw after the etch? Also digging the all blue caps and resistors.

RAW.

* sort of raw- after etching, I wash the F.C. and toner mask off with acetone, then give it a good scrub with my dedicated "nasty brush." After that I apply a coat of olive oil (first pressing*) and let it sit for a couple minutes before wiping the oil off. Scientists will laugh at me for not knowing if or why the olive oil works.. but the alchemists understand why I do it!
oh, & thanks for noticing the blue thing

Here's an over-etch fail that I didn't oil:

@Barry, I know aluminum doesn't "rust," but what is this^?

Do you heat your ferric chloride before etching? I need to take another crack at it as I've only really tried it twice and didn't like my results and have a big bottle of it eyeballing me every time I go in to the garage.

Edit: I forgot to mention how bad ass this build is, but to be fair I am just sick of telling you how awesome you are

Thanks!
@peccary got me feeling like:

I start my stopwatch and float the enclosure in the room-temp F.C. for 1 min, then lift it out and hit the *face of the enclosure* with my heat gun and dunk it again until 2 minutes comes around and hit it again each minute, on the minute, until it looks ready. I wish there were a good rule of thumb, but there are too many variables for that- even down to the blend of aluminum the part was cast with. I've done anywhere between 4-9 minutes with different heating methods over the years.

If you're doing multiple etches in a row, be careful. The F.C. maintains heat and works faster each subsequent etch.

 

[Barry]

Thanks! I'm totally okay with the knobs, but there were a fair number of memes deployed in opposition of the idea so I thought I'd goof in remembrance.
You know, I thought I read someplace that it's inspired by a Muff as well, but I couldn't recover the thread that mentioned it, so that's what aided my knob choice here. After playing with it for awhile though, it doesn't feel like a Muff to me at all.. but that only means that Bugg's ideal "Muff" is a bit different from my ideal "Muff," and there isn't anything wrong with that!
Glad you dig the LED's



You know it- glad to finally join the Caustic Chemical Club!



RAW.

* sort of raw- after etching, I wash the F.C. and toner mask off with acetone, then give it a good scrub with my dedicated "nasty brush." After that I apply a coat of olive oil (first pressing*) and let it sit for a couple minutes before wiping the oil off. Scientists will laugh at me for not knowing if or why the olive oil works.. but the alchemists understand why I do it!
oh, & thanks for noticing the blue thing

Here's an over-etch fail that I didn't oil:

@Barry, I know aluminum doesn't "rust," but what is this^?



Thanks!
@peccary got me feeling like:

I start my stopwatch and float the enclosure in the room-temp F.C. for 1 min, then lift it out and hit the *face of the enclosure* with my heat gun and dunk it again until 2 minutes comes around and hit it again each minute, on the minute, until it looks ready. I wish there were a good rule of thumb, but there are too many variables for that- even down to the blend of aluminum the part was cast with. I've done anywhere between 4-9 minutes with different heating methods over the years.

If you're doing multiple etches in a row, be careful. The F.C. maintains heat and works faster each subsequent etch.

It doesn't rust as only iron and steel rust (an oxidation specific to those metals), that doesn't mean aluminum doesn't oxidize or corrode

 

[dawson]

It doesn't rust as only iron and steel rust (an oxidation specific to those metals), that doesn't mean aluminum doesn't oxidize or corrode

COOL!
Thanks, Barry.

 

[Feral Feline]

As you know, I'm a big fan of your SCHMORG.

However, I've come to expect certain things of late:

Cool graphic
Etched perfectly
Choice circuit
Clean build
Great build-report
Copulating capacitors

I mean, c'mon, not so much as a reach-around in this build!


However, the ménage-a-trois LED more than makes up for it.

 

[Bricksnbeatles]

To add to what @Barry said (though he certainly knows much, much more than me):

Keep in mind–– The dull grey luster of the surface of a Hammond enclosure; the near-black you get from one of your etches; the blood red of a ruby; the royal blue of a sapphire... They're all Al2O3– just with different 'impurities' that pigment them.

As far as stuff I know nothing about- If I had to guess what caused that weird brown reaction in that etch you got, the fact that, I'm assuming it appeared after the etch and not during (based on the fact that you attribute it to not being wiped with oil), leads me to believe it may very well have a basis in rust (or at the very least some form of iron oxide). I've seen reactions like that more than a few times on etched aluminum, but only specifically in Ferric Chloride etches. I don't know exactly what the byproducts are of a ferric chloride etch on aluminum, but the fact that you start with Al (and some remaining Al2O3, which is more etch resistant, but not etch-proof altogether) on one side of the equation, and FeCl3 on the other side, and have a reaction that gives off Cl2 (chlorine gas) and presumably AlCl3 (Aluminum chloride- one thing that, in solution, would explain some of the yellow liquid byproduct of a ferric chloride etch), means that you need to have that Fe (and the three Oxygen atoms per consumed Al2O3 molecule) go somewhere, and there's a good chance that could manifest in the form of Fe, FeO, Fe3O4, Fe2O3, FeO(OH)[?], Fe6O5(OH)7Cl [?], or your common old rust; FeO(OH)3/FeO(OH). I don't know the exact chemical processes going on in the reaction between Aluminum and Ferric Chloride, but there's a decent chance there's something with an Fe left behind in the etch after you clear away the waste byproducts, and that the oil prevents it from either oxidizing into one of the various aforementioned iron oxides, or something else of that nature, by means of leaving a protective barrier between it and the surrounding atmosphere. Chemistry is a wild thing, and there are way more variables at play than just what is immediately obvious.

 

[dawson]

As you know, I'm a big fan of your SCHMORG.

However, I've come to expect certain things of late:

Cool graphic
Etched perfectly
Choice circuit
Clean build
Great build-report
Copulating capacitors

I mean, c'mon, not so much as a reach-around in this build!


However, the ménage-a-trois LED more than makes up for it.

Oh no! You're right- look at them all just standing around looking at their shoes with their hands in their pockets like they've never seen a disco ball or a crack pipe in their life!

I'm very sorry for the flacid nature of this recent content, @Feral Feline. I really have NO excuse- my capacitors should know better: this is the "ACID RAIN FUZZ," not "Pastry Group Bible Study!"

 

[dawson]

To add to what @Barry said (though he certainly knows much, much more than me):

Keep in mind–– The dull grey luster of the surface of a Hammond enclosure; the near-black you get from one of your etches; the blood red of a ruby; the royal blue of a sapphire... They're all Al2O3– just with different 'impurities' that pigment them.

As far as stuff I know nothing about- If I had to guess what caused that weird brown reaction in that etch you got, the fact that, I'm assuming it appeared after the etch and not during (based on the fact that you attribute it to not being wiped with oil), leads me to believe it may very well have a basis in rust (or at the very least some form of iron oxide). I've seen reactions like that more than a few times on etched aluminum, but only specifically in Ferric Chloride etches. I don't know exactly what the byproducts are of a ferric chloride etch on aluminum, but the fact that you start with Al (and some remaining Al2O3, which is more etch resistant, but not etch-proof altogether) on one side of the equation, and FeCl3 on the other side, and have a reaction that gives off Cl2 (chlorine gas) and presumably AlCl3 (Aluminum chloride- one thing that, in solution, would explain some of the yellow liquid byproduct of a ferric chloride etch), means that you need to have that Fe (and the three Oxygen atoms per consumed Al2O3 molecule) go somewhere, and there's a good chance that could manifest in the form of Fe, FeO, Fe3O4, Fe2O3, FeO(OH)[?], Fe6O5(OH)7Cl [?], or your common old rust; FeO(OH)3/FeO(OH). I don't know the exact chemical processes going on in the reaction between Aluminum and Ferric Chloride, but there's a decent chance there's something with an Fe left behind in the etch after you clear away the waste byproducts, and that the oil prevents it from either oxidizing into one of the various aforementioned iron oxides, or something else of that nature, by means of leaving a protective barrier between it and the surrounding atmosphere. Chemistry is a wild thing, and there are way more variables at play than just what is immediately obvious.

Far out, man.

I knew you were bright chap, but had no idea you're such a renaissance person, @Bricksnbeatles
(Or you're goofing me and this is too far over my head for me to know it's fake!)

*to be fair- I don't think I scrubbed and rinsed that failed etch before it turned brown, as well as not adding oil.. I just make a bigger deal about the oil because I'd like to remain convinced that it's working (first pressed olive oil only*!)