Project: Fuzz

Has it really been 5 months since I posted a completed effect pedal build? Holy cow. Time to end that.

I present to you my latest build, a fuzz pedal:

A couple of things about this one.

1. This is my first active build in a 1590a enclosure. I had done a few pickup simulators a couple of years ago. I also built three utility boxes (2x buffer, 1x power conditioner) in 1590a-sized boxes back in March. As for actual active effects capable of bypass, this is my first.

2. This is the “proof of concept” for the new (to me) finishing technique I am developing. It is not as simple as you would think. As you can see, it involves glitter and epoxy, but I am discovering that certain techniques and materials provide the best results. Obviously, the finish on this one is not perfect. There are a few air bubbles, and a few areas of thin glitter. I have a ton of new ideas on how to improve the process and results, and will be sharing them as I test them.

3. The circuit isn’t anything unique or special. It is basically an Axis Face, minus the “smooth” control. When I tested on my breadboard, I wasn’t a big fan of the super low gain of the PN2369A and BD139. I ended up using a BC107 for Q1 and a BC109 for Q2. The HFE is 165 for Q1, and 283 for Q2. It sounds good.

5. There are two 3mm white LEDs mounted to the switch, consuming 6mA total. They make the sparkle areas glow nicely when the effect is engaged. No popping.

6. The knobs are not knobs at all. They are screw protectors, made by Crown Bolt and purchased at Home Depot for next to nothing. There is a black cover pressed on to the potentiometer shaft, and a white cover slipped over the black one. I like it.

Here are the project files for this build. Included is the ExpressPCB/ExpressSCH files, and a PDF toner transfer. Note that there are two PCB files– one has curved traces, the other does not. Your choice, I suppose. Note: This is not an easy build. The board is very tight, the pots require filing to get them to fit, and 1590a enclosures present challenges that are probably best avoided for novice builders.

Project Files [ZIP]

As always, if anyone builds one of these, I would love to see the final results.

More to come!

Epoxy Experiments

I know, I have not actually built anything in a while, but it is not for a lack of trying. I have had a very busy spring and early summer doing projects around the house, and watching the Blackhawks win the Stanley Cup. I hope to be building again soon.

I have a few things in the works, with most of my time going towards a delay pedal with companding, tails, modulation, and an effects loop (wet only, once through or infinity) in a Hammond 1590TRPC.

I do have some cool stuff to report, though. I was surfing around one day, and stumbled upon this topic, which chronicles the building of a sparkle green Telecaster. That got me thinking, and I have been doing some experiments.

I started my experiment by taking a piece of aluminum stock, painting some square areas on it, and etching it with HCl+H2O2. The plan was to put some glitter in the etched areas, and clear coat it. It was not to be, however, and two failed etch attempts later let me looking for a new plan.

The new plan was this: take the same aluminum stock, sand it flat, and drill some holes. Put some parchment paper (silicone impregnated paper) over the holes on the bottom, secured with blue tape. Then, place a drop of super glue from the top, apply glitter, and epoxy over that. Here is what resulted:

As you can see, there is some potential, and some problems. The main problem is that the epoxy I used– Permatex Crystal Clear 5-Minute Epoxy– set way too fast. I had no time to attempt to remove air bubbles. In fact, you can see that some of the epoxy is kind of just piled on there. Not pretty.

The potential is there, though. I am going to switch to 30-minute epoxy to see if I can get rid of the bubbles. If I can get a more even glitter coat, and be more accurate with the epoxy, I could make something really cool.

Experiment two. Since the epoxy in the first experiment didn’t look good, I decided to see what would happen if I smoothed it. I started with sandpaper, which didn’t make a dent, and quickly progressed to a file. Once I got near the metal, I switched back to sandpaper. As you can see, one row of holes has a beveled edge, and the other has a straight edge. Sanding flush to the metal gives a nice, finished effect.

Experiment three. Since I had better success with the filing-and-flattening, I decided to try another one. This time, I drilled four different sized holes in the aluminum, and skipped the parchment paper and super glue. All I did was drill some holes, cover the bottom in blue tape, add glitter from the top, and drip on epoxy. After it cured, I filed it down, and then used a razor blade to scrape it flush with the metal.

I think it looks really good, especially considering I only scraped it. No sanding, no polish.

The next step is to incorporate this into a pedal. I decided to build a simple little silicon fuzz in a 1590a enclosure. I chose a fuzz not only because I have all the parts, but becauseĀ  I will be able to file the word “FUZZ” into the top of the pedal, and fill it with glitter and epoxy. I will then most likely drill a bunch of random holes, and glitter/epoxy them as well. It should be pretty cool.

More to come!