In 2010 we came out with the Analog Man Astro Tone fuzz, a new fuzz based on the
old Sam Ash and Astrotone fuzzes but improved for better sound.
For more info, see
buyanalogman.com
Vintage Effect Pot Repair
By Analog Man
Here is a pedal we got in for repair and some fabrication work in Aug 2005, from the UK. We have to do this sort of work often on old pedals like E-H pedals due to pot damage from being stepped on. This pedal has a recessed knob area so very rare for this sort of damage but somehow it happened (blame Roger).
This pedal arrived with no bottom plate, no battery clip, and
not working. There was some internal rewiring also, as a British
Fuzzface jack had been replaced the original grounded output jack.
A ground wire was running around inside from that jack which we
removed when we added the original switchcraft jack.
I have a mint in box Sam Ash Fuzzz Boxx which is the same
pedal, made by the Astro Amp company in '66 - '67, so I could
make sure I restored it with the correct parts. The Astrotone
knobs seem to be unoriginal but I will leave them on. We have had
several of these pedals over the years, there is one version
without the recessed knobs, we had a 1967 model like that.
The Sam Ash Fuzzz Boxx is
the first pedal I ever cloned, in the early 1990s. Here is the
one I made at left, build into a CRAZYTONE fuzz box that I got
from Angela Instruments (remember their crazy catalogs!). Mine
was really a clone, down to the artwork on the board and the
board mounted pots. Works pretty well!
Here are the insides, after I replaced the output jack and
rewired it like mine. His is an early 1967, you can see the 1966
pot codes below. My red one has 1966 pot date codes too, but
seems to have different type capacitors (film vs ceramic) and
circuit board material. Mine also has an original plastic input
jack. The input jacks have a built in switch to disconnect the
battery (+) side when you unplug, it was before they figured out
the simpler method of using a stereo jack with the battery (-)
wire going to the RING connection.
After rewiring and installing an old blue battery clip that I
found in my drawer, it worked but not well. Looking closely we
saw that the VOLUME pot was falling apart. It is the one at the
left, note the space under the metal cap and the crimp legs bent
out. This happens when someone steps on the knob. EH pedals used
nylon pot shafts which often broke before the pot would open. If
that happens, and you have a donor EH pot of any value with a
nonbroken shaft (good luck), you can follow the steps below and
install a new shaft and rotor into the old pot.
First we had to unscrew the knobs and pots to remove the board
from the case. Then we needed to remove the pot from the board,
as it was impossible to recrimp it as it was. Also we could clean
it up nicely after removing it. At the left you can see the three
solder lugs desoldered and lifted up to allow removing the pot.
The traces are very fragile so it was done carefully but the top
one broke a bit, not a problem as the tab would about reach the
next wire. I added a short jumper wire to the next pad anyway,
hidden by the solder, just to make it stronger.
After removing the pot, I carefully dissassembled it. Some
later pots will not come apart but this style usually does. I
cleaned out the pot with a Qtip and red DeOxit spray cleaner/lubricant,
and added a dab of grease on the top cover to make it turn smooth
like a new pot. When you sprayclean pots, the cleaner loosens the
grease and that is why the pots will turn too easily after spray
cleaning. The black part has the shaft and rotor, and will come
off on this style of pot for rebuilding.
Then I put the pot back together and crimped two of the legs
so I could test it. You can use long needleneck pliers but I have
a STRAIN RELIEF plier that works really well for recrimping pots
as it reaches around a bit like a C-Clamp. I then tested the pot
with an Ohm meter to make sure it was working over it's full
range with no dropouts. It was fine so I crimped the other 2 legs
and popped it back in the board.
Here is the pot reinstalled and soldered back in.
Here is the top of the pot installed, nice and tight now. You
can see the date code 1376647. 137 = manufacturer (CTS), 66 =
1966, and 47 = 47th week of 1966. Last digits on the other set of
numbers are 10K meaning a 10K pot.
Next was the bottom plate. They were made from sheet aluminum
(or aluminium as they say across the pond) so it would not be
hard to make a good reproduction. I had some scrap aluminum from
a box, just big enough so traced my Sam Ash bottom and cut one
out. Laying it on the handmade sandcast ASTROTONE, I trimmed off
some excess. Then used a large flat file to get the sides
straight and deburred, and round off the corners. Finally when it
fit well, I used scotchbright (synthetic sandpaper pads) to make
the edges smooth and safe, and make both top and bottom very
smooth and clean.
Hope you enjoyed this repair as much as I did, and can use the
info to repair some vintage effects in the future.
Regards, mike ~^v^~ aNaLoG.MaN ~^v^~ vintage guitar effects
http://www.analogman.com