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Great work!
I'm at the beginning of a similar project, will probably steal some of your ideas

hi,
not much of a help, but your tl072 doesn't get 9v on pin8 while regulator does, that is strange as they are on the same potential - trace.
Did you check for shorts between anything that is close but should not be connected?
you can also try to take out the ICs and measure voltages on socket pins, see if they change, if you get 9V on tl072 pin 8 and PT2399 pin 1 maybe something's wrong with the ICs

put a 1M resistor on a switch in series with the pot

I sold Carbon Copy, twice. First time for paying the bills, second time for a new amp. I still miss it, but it goes against my principles to buy another one because it's not diy , so i get by with my DBD clone

Well, if you put a volume pedal before dirt, it acts as a guitar volume pot, it doesn't lower the volume but cleans up the sound. If you put it after dirt then you are controlling volume of a distorted sound. 

I face the same woes,
as i mostly play thrash metal where right hand tight picking is usually more important than left hand fingering wizardry i have trouble with precise and tight picking + singing at the same time. But i have a very good rhythm player by my side so i can always turn myself down a little bit when i sing and play

yes to both.

looking at the video it doesn't transfer toner completly.
In my expirience if the toner isn't completly transfered to the enclosure so that no toner is left on the paper, it won't work as an etch resist.

I hope somebody proves me wrong, im tired of all the sanding and ironing and cursing because one half of one letter hasn't transferred well so i have to start all over again. 

Alright, here is the buffer schem with power filtering and the input impedance cap.



Why isn't the pot value so important?

just one thing, your power supply portion of the schematic doesn't have any filtering. It has a small value resistor which can help reduce noise and interference, but for power supply filtering you would use capacitors. Every power supply has some ripple, that means that DC voltage isn't excatly a constant value but it fluctuates.That fluctuations can introduce noise.

Here's a picture to help clarify things
Have in mind that the numbers on the pictures are purely for demonstration, i haven't done any math, so don't take them as is.


Top left picture shows your power supply fluctuations, according to the picture, it fluctuates between 9 and 8.5V every milisecond. We need a cap here.
Why capacitors? Capacitors are devices used to store charge/energy. As such they need some time to to fully charge/discharge, as you can see in the top right picture.
The trick is to use capacitor which needs much longer time to charge/discharge than the actual time of your power supply variation. That way, when your PS starts dropping from 9 to 8.5V rather fast, capacitor discharges much more slowly thus making the voltage much more stable as you can see in the bottom left picture. We can say that when PS voltage starts dropping, the capacitors gives it's own accumulated charge to compensate.
Bottom right picture is the usual way of power supply filtering in pedals.

Hope this helps

1. i would say that that the value isn't of much importance, but i may be wrong
2. yes it is

with just R18 and R19

2. My mistake, i thought ypu were building a wah, prolly had few too many beers
Vb is between 1M resistor which run from Vcc to +input of opamp then another 1Mres from +input to ground

I believe you could ommit the 100nf cap before 2nd opamp input, but i may be wrong.
3. If it's a vol pedal, then the pot is used for volume change, no res change necessary

why do you need a pot between the buffers?
it would only serve if you want to attenuate the signal
and why use two buffers in series?
if you wanna use two buffers, one for input and one for output, you would connect wah input where the wiper is connected and wah output on the input of second buffer
but, if you want this arrangement, you don't need 1M res to ground before second 100n cap, in fact i would say you don't even need the second 100n cap because 10u cap before pot does the ac coupling

great looking etches!

tThanks guys for all the nice words

Very nice & tidy build. The etch looks clean. If I would suggest one thing it would be to get yourself a tooth brush (or something of the sorts) and you can use it to clean the PCB off of stuff that clings on like dust and even wire trimmings. Just a suggestion.


Cody

Thanks for the tip

Cool, how's it sound?

Gotta check the data sheet, some suppliers don't follow all the same conventions.

Fuzzy. Can't really tell, i'm not much of a fuzz guy, and never played a fuzz besides BM, but i like it