Advice needed: Building in Dunlop Fuzzface Case

[Pete-Galati]

I bought a recent Dunlop FuzzFace a few months back, pretty much just because I'd never actually owned a Fuzzface and I figured I had to get it out of the way. :roll:  Should have built it myself.

Here's a peak at the insides of what Dunlop's building.  Egads:




So I figured, ok, I'll just build this right some day because I love the case that it's in, it just drives me up the wall how they attached the PCB.

I figure that I'll probably build it close to the Roger Mayer mod about 7/8th down this page: http://www.geofex.com/Article_Folders/fuzzface/fftech.htm

But where the circuit board is supposed to be screwed down, those bosses aren't drilled and tapped.  And I only have limited experience tapping holes, and decades ago, when I just used what they handed me at work, and squirted some oil in the hole, and hoped I wouldn't break the tap!

But what size drill should I use, and what tap should I get?  I'm sure I could buy the tap at the nearby hardware store.  Are there guidelines for selecting what size drill to use for what tap?

Thanks.

Pete

[waldo041]

you could try these instead

small bear:
http://www.smallbearelec.com/Detail.bok?no=76

mouser:
http://www.mouser.com/index.cfm?&handler=data.listcategory&D=*561LAD187*&terms=561-LAD187&Ntt=*561LAD187*&Dk=1&Ns=SField&N=0&crc=true

peace,
waldo

[C Bradley]

But what size drill should I use, and what tap should I get?  I'm sure I could buy the tap at the nearby hardware store.  Are there guidelines for selecting what size drill to use for what tap?

Thanks.

Pete

You might try a google search for American Vermont or Union Carbide drill and tap charts. I used a lot of that when I was working in different machine shops. I think the rule of thumb is that the drill diameter should be 80% of the finished thread diameter, but I always went with the chart.

80% sounds about right. For a 1/4-20 NC hole, a #7 drill is recommended. That's .201", IIRC. 80% of .250 would be .200

When tapping a blind hole (one that doesn't break through) you should turn the tap a full turn and then turn it back the other way 1/2 a turn; this breaks the material the tap is removing into smaller chips, which relieves some of the strain on the tap. When you get close to the bottom, remove the tap and blow the hole out with an compressed air or tap on the back of the enclosure to knock out the chips, then you can tap another full thread or two.

[formerMember1]

hey, that is a good question man, i just signed onto the forum to ask the same thing,  I too have the same fuzzface, and what i did was take the pc board out and put it in the garbage, i am using the wire and pots and jacks for spare parts.  I am building the axis face from fuzzcentral.  You should check it out, it looks really good, i can't wait to place my order for my parts, (after i make sure i didn't forget anything)

cool

Luckily, my father is a carpenter, and he has virtually every tool you could imagine, (except i bought a new drill press, since our old one is pretty shot)

good luck my friend

[AL]

The plastic stand-offs are really convenient. If you can't get hold of those you could always get some regular stand-offs and instead of drilling your enclosure use some JB Weld to attach them to your case.

AL

[Pete-Galati]

Thanks guys.  I was thinking afetr I posted that that I should ask for alternatives to drilling & tapping too.

It's not like my pedal is going on a world tour or anything, and needs to be screwed down.  But I'd found pictures of the insides of FuzzFaces from years ago, so I knew how they were supposed to be built.  More or less anyhow.

I'm not really sure what to do with the plastic standoffs though.  Do you just drill those, and attach the board with sheet metal screws, or something like that?

I remembered that I bought two 10-24 taps to try to repair stripped threads in a SoundCity SC120 chassis.  I just looked at those, still in the Sears Hardware packaging, and they say to use a "25" drill.  25?  What the?

This web page seems to indicate that a 25 drill is 0.1495, which is somewhere between  9/64" and 5/32".  Now I have both of those sizes.  I bet I'd get away with the larger 5/32" size drill bit.  Those bits are so close in dia. that it's real hard to tell the difference.

Oh, forgot the webpage:
http://www.evergreen.edu/biophysics/technotes/fabric/number.htm

Pete

[Pete-Galati]

hey, that is a good question man, i just signed onto the forum to ask the same thing,  I too have the same fuzzface, and what i did was take the pc board out and put it in the garbage, i am using the wire and pots and jacks for spare parts.  I am building the axis face from fuzzcentral.  You should check it out, it looks really good, i can't wait to place my order for my parts, (after i make sure i didn't forget anything)

cool

Luckily, my father is a carpenter, and he has virtually every tool you could imagine, (except i bought a new drill press, since our old one is pretty shot)

good luck my friend

I'm not quite sure if I can bring myself to tossing the PCB in the trash.  The transistors migh actually be rather good because Dunlop seems to have gotten NKT275 transistors built for them.  But not being anything even remotely close to a Germanium transistor expert, I have a seaky suspicion that it's an NTE grade transistor that's just relabeled for them.

I was considering reusing the pots and jacks.  I haven't had the thing open for a couple months (old pictures) so I don't know what values they are though.  And I have some SwitchCraft jacks.  The baterry clip loks better than what I have though, so I want to use that.

If Small Bear, or someone else could get those mic stand type cases that Dallas Arbiter & Dunlop used, I'd think it'd be a decent seller, and not ofr just FuzzFace clones.  Because they have a lot of room inside them, and they're really comfortable.  Biggest problem is that it seems to be difficult to change the battery.  Getting that screw back in!!!

Pete

[AL]

Pete,

No need to drill the case if you're using plastic stand-off's. They have a sticky back on them. Just peel off the film and stick them to the enclosure. That's it - easy. You may or may not have to drill the board however. Sometimes the holes for mounting the boards aren't big enough for the plasict stand-off. The radio shack boards are like this.

As for attaching the boards to the plastic stand-off's - just push them down onto the stand-off and they snap in place. No screws needed. They're really convenient.

Ideally, I think that using the metal stand-off's with the screw is probably the "better" method - as far as long term stability - but the plastic is much easier. Your choice.

AL

[formerMember1]

well, i like my rubber feet on the bottom of my wahs.  Easy removal for battery access.   SO i am gonna drill 4 holes around the perameter of the fuzzface shell, and use the four screw in rubber feet.   I also put a battery holder in there side ways. Got it off smallbear.  That way my batttery don't fly around when i travel.  That is my exp... and solutions....

Oh yeah,  The transistors in the dunlop fuzz suck.  It is your option you, personally I would rather use silicon over germanium. The axis face i was talking about is silicon and arranged to sound like germanium.  Then you don't get into $ and temp problems.  I actually prefer a silicon fuzzface anyway.  Hendrix did too.  After i build the axis face from fuzzcentral, i am gonna build a silicon fuzzface(axis fuzzface)

I still gotta get that JB weld , to fill in the potholes, so i could redrill them smaller.  Also gotta drill a 3 rd hole for the smooth pot.  I picked up a unibit.  It graduates down in 1/32" .  I am thinking now, maybe i should have gotten a short unibit.  Instead of it dropping down in 1/32".  Cuz now when i drill it might go through the other side of my hammond 1590B cases,(dont know)  Anybody prefer the short or long unibits?
sorry for rambling and highjacking, just thought i might as well post it here since PETE  was talking about drilling. :wink:

Hey, pete or anybody else,
Those posts in the fuzzface, you know the ones you wanna drill so that you can mount your pc board too.  Are those hollow or solid?

[Pete-Galati]

I assume that those posts are solid.  Here's a look at that picture before I shrunk it for use in this forum.  I'll just post the url of the more or less full sized one:

http://amplifyer.home.comcast.net/fuzzy/fuzzyguts.jpg

Here's the webpage I mentioned earlier.  The Dunlop casting seems to be very close to the '80s FuzzFace.  Search for the words "Rare blue with white lettering":

http://www.foxroxelectronics.com/scrap.htm

Not all of the castings had that little ridge that seems to be there to keep the battery in place.

I bought a few NTE158 Germanium transistors when I built my Rangemaster based pedal.  It's their substitute for the NKT275.  I always buy several spares in case I want to build something twice (never happens) or make drastic mistakes (happens all the time) or both.  So I'm kind of expecting to use a couple of those since I owe Visa too much these days.  I need a few months without big purchases!

Are there more people preferring silicon transistors in FuzzFaces these days?  Germanium seems to be the big buzzword that many of the advertizing departments love to use.  My Rangemaster pedal turned out much better than I was expecting, and it was the first time I'd put anything together using a Germanium transistor.  

I obviously can't speak as the voice of experience though.  Don't know how it would have turned out with a NOS one from Small Bear, or a silicon PNP from PartsExpress.  I just ordered parts I didn't have, and put the thing together.  Slowly.

I have several Joe Gagan schematics of FuzzFace based pedals, from a few years back.   I brought them over from an old computer that I had to use when my main one got fried by lightening.  I was giving a little bit of thought to building his Easy Face pedal, but that would require ordering parts.  Is Joe hanging at this forum?  Does he still provide access to those schematics he did a few years ago?

Pete

[formerMember1]

germanium is the best for Rangemasters.  I built one with a OC44 off smallbear.  As far as my exp. that and the other OC71(or something like that) are the only ones that actually sound good in a RM.  NKT275 are supposed to be good  too, but i never was able to get one.

About that blue fuzzface with white lettering, Is that rare and worth some money?  I know where one is at, in my area.  Around $400 is the asking price.  I tried it too, it sucked, really bassy and didn't clean up at all with the guitar volume knob.

As for the fuzzface you have, i have the same one.  What i meant by silicon transistors is, I prefer them in a fuzzface over germanium.  Silicon was harsher but more inyour face then the germanium. Hendrix at woodstock(need i say more) :lol:

that is my opinion though

[Pete-Galati]

germanium is the best for Rangemasters.  I built one with a OC44 off smallbear.  As far as my exp. that and the other OC71(or something like that) are the only ones that actually sound good in a RM.  NKT275 are supposed to be good  too, but i never was able to get one.

I probably would have been more worried about using a more proper transistor in mine, but I used .015uf for an input cap to give it more of a full range boost.

About that blue fuzzface with white lettering, Is that rare and worth some money?  I know where one is at, in my area.  Around $400 is the asking price.  I tried it too, it sucked, really bassy and didn't clean up at all with the guitar volume knob.

But you notice that that one was modified.  There might be a good reason for them being rare.  Rare usually brings good money for famous pedals for some reason, whether they're good or not.  I'm not a pedal collector though, and don't understand what's behind it.

As for the fuzzface you have, i have the same one.  What i meant by silicon transistors is, I prefer them in a fuzzface over germanium.  Silicon was harsher but more inyour face then the germanium. Hendrix at woodstock(need i say more) :lol:

that is my opinion though

I wonder if this Dunlop FuzzFace could be improved at all by tweaking those trimpots that that squirted sealant into the holes of.  I assume that those are bias pots for the two transistors.

Pete

[formerMember1]

well, you can pick that glue out of the trim pots with a pin or something.  Dunlop added those trimpots.  One controls a little of the biasing and another controls the volume.  If you look at the one closest to the switch(in physical appearence) that is the fuzz or bias one.  More info on this is here. scroll down untill you see a picture of the fuzzface you got.(bottom of page or so)

http://www.analogman.com/fuzzface.htm

Also, you will have to replace some of the resistors if you wanna change transistors.  
the ones to change would be R1, R3, R5.  What i did was replace them with pots to bias.  Look at Aron's main page for info on this.

In short, what you are doing is replacing say the R1(8.2k) with a 10K pot, and replacing the R3(56K) with a 100K pot and also R5 (470ohm or 1K) with a 1k pot.    Before you solder the pots, you measure them with a multimeter and set their values to the original resistors.  Then you try to get the correct voltages on the transistors by adjusting the pots until that happens.  Then you carefully remove the pots and measure them with the DMM, then replace with the cloesest resistor value.
That's what i did anyway, now that i think about it, you might be able to do some of the biasing with added trimpots dunlop put on  the board.

You do the above when replaceing the transistors.  which i recommend.  the dunlop ones suck in my opinion.  
Get a matched pair off smallbear, they are good, and already sorted for you!!

good luck

I now decided to build my own board and get new pots and jacks and just use the enclosure.  I wanted to start off new,  PLus i got sick of the pedal sounding good one day and bad the next.

[Pete-Galati]

I haven't found the Dunlop FuzzFace to be all that satisfying so far.  The only situations it worked well for me was when driving it with a booster pedal, and using it for slide guitar.  But I'm not a very good slide player, so....

I've been through a lot of OD and distortion pedals in the last few years, but the one I keep going back to is the ProCo "Vintage" Rat.  But I figure I should take a shot at building a FuzzFace.  Can't do worse than Dunlop, right?  I do like my Dunlop picks, and my Dunlop brass slide, I'm just not finding a good use for their version of this classic old pedal.

And I'm a little leary about trying the Dunlop versions of the MXR pedals now too.

Pete

[formerMember1]

yeah try searching the forum for some info on the mxrs.

I have a dunlop GCb-95 wah, i don't like it at all. So what i did was take everything out and am replacing the board with my own home made board and parts.  Gonna build the vox clyde mccoy wah, like hendrix's.\
In other words, i am just using the enclosure.

you should visit this site if you haven't already.(that is the axis face silicon rev 3 i was talking about)

http://fuzzcentral.tripod.com/axisfacesi.html



I also have a dunlop univibe which i might sell.  I will probably build my own.  Anybody know how these compare to vintage univibes?

I also have another dunlop univibe that doesn't work, I bought it really cheap off a guy, i am just gonna use the enclosure probably.  (i don't know what he did to it, but a jack is broken and a pot is snapped right off)

[Pete-Galati]

Thanks for the earlier info about which trimpot is which formerMember1.  For some ridiculous reason, I just figured, two trimpots meant two bia pots.

I was digging around in the schematic forum yesterday (still finding my way around) and ran into this schematic of the Dunlop FuzzFace:

http://www.diystompboxes.com/pedals/ff99.gif

Strikes me that they made a simple design more complicated.

For A/Bing:

http://www.montagar.com/~patj/fuzzface.gif

I'd heard some things I didn't like about how Dunlop built their versions of the old wah pedals.  By now, I forget what that was about.  Some mass production thing.

But I've heard that Vox still makes respectable wah pedals though.  Have forum members been pleased with Vox wah pedal construction?

I haven't messed with a wah pedal in a long time.  I broke my Cry Baby years ago trying to turn it into a volume pedal.  So I got a Morley to replace it, and didn't get along with the thing at all.

Pete

[formerMember1]

i am sorry man,
I ahad a whole big long page of step by step instructions for you here, I typed for ever, I meant to put a link in here and accidentally closed the window erasing it all.  :oops:   I'll have to post it in the future when i got time.

In very short words i found the best mods to the dnlop fuzz were to :
change transistors,(socket them)
bias it right,
change C3 cap(orange little thing) to a metalized film .01uF cap
change the 500k vol pot to 100k and the fuzz pot to 1k audio reverse taper pot from smallbear.(i didn't try that fuzzpot yet, but hear it is the best thing out there now)

good luck and sorry :wink:

[sir_modulus]

For the drilling...I don't see the problem too clearly. If you have a Home Depot near you, they sell Vermont tap and drill sets. You get the right tap, and the right trill bit for it, and it gives you the screw size. I'd get either 10-32 or 4-40 machine screws(with non flat heads), and buy the corresponding tap set. That's for the Box. For the board, just drill the holes bigger than the threads on the screw, but smaller than the head, and you're set.

As far as I've seen, the Dunlop transistors are not that great. They may be real germaniums, but no time is taken to match them, or even test them beyond to see if they work. For the price of em, I'd just go with the small bear ones, because they sound great, and they're hand tested and matched for you!

As for mods....
http://www.geofex.com/Article_Folders/fuzzface/fffram.htm
Just read through that, and look at the differences between the various fuzz faces. Phillip's site (fuzz central) has a good version of the fuzz face (sounds real nice). It's a bit different, but I like it. Personally, I'd just socket a lot of the components (input cap etc..) and tweak the circuit to your liking before building it in there.

As for the existing parts, I'd leave the jacks and battery snap, but scrap the pots and get new ones from small bear. They just have a better feel to them, and have a more suitable taper for a more linear feel.

Cheers,

Nish

[formerMember1]

hey pete, i just remembered something i thought would be useful to ya,

One of the reasons i threw my dunlop fuzzface pc board away was because it had the switch on the board, and i didn't feel like removeing it and figuring out what to do next,

that is another reason why i am building my own board,

Let me know how it works out for you when you drill and tap the screw holes in the fuzzface enclosure.

:wink:

[joegagan]

You can just drill the holes in the standoffs and tap some self tapping screws right into the holes if you choose your bit size carefully.

I re use those carling switches from the PCB on late model dunlops but I have found the fastest way to remove them to be to use a cut off wheel on the Dremel to cut the pcb around the switch lugs, then desoldering is much easier!

Re using the late model dumop board is a waste IMO, it doesn't take mods well, too much work, never sounds as good as a simple Ff anyway (IMO)

I did a 'feng shui(sp?)' type term strip easy face a while back
see pics