1590a boxing question

[jonboper]

I'm working on my first a 1590a build and am having a really hard time getting things to fit. Especially with the mono jacks, it's difficult.

My question is about whether anything can be touching...I'm assuming the tips and sleeves cannot be touching anything - either the tip/sleeve of opposite jack OR the enclosure itself...is this correct? Is there anything else I need to be worried about making accidental connections?

(I was making a Temple of Giants but that didn't fit. I changed it to an OK which should fit.)

[Ben Lyman]

the sleeves are a common ground so they can touch each other or even the walls of the enclosure. I suppose in theory, you could even cut the tabs off the sleeves (of certain jacks) to gain more room, some people don't even solder any wires to the sleeve tabs because the sleeves make contact with the enclosure (unpainted insides) and form a ground. I recently crammed a Big Muff into a 1590A and I had to use "Lumberg" jacks, look them up and keep a couple in stock for emergencies. Here's a link to the pics of my "micro-muff" 
http://www.diystompboxes.com/smfforum/index.php?topic=64752.msg1105423#msg1105423

[Mark Hammer]

I'm currently working on 1590A builds #4 and 5, and whatever convenience is provided by their small size, is counterbalanced by the sheer hell of getting things to fit.  Some tips, which others can (and will) supplement:

1) Learn how to fit your stompswitch chassis as close to the front skirt of the box as possible.

2) 2.1mm power jacks come in two flavours: innies (secured by a nut inside the chassis) and outies (secured by a nut on the threaded collet outside the chassis).  Innies lie pretty flush with the outside of the enclosure, but at the cost of taking up a lot more space inside.  ONLY USE OUTIES.  If you install the power jack at the rear skirt, and can bend the solder tabs to the side without breaking them, then the little space between the two chassis screws can be used efficiently without taking up valuable real estate.

3) Open jacks, like these - http://www.smallbear-electronics.mybigcommerce.com/1-4-in-mono-switchcraft-11/ - allow for closer spacing of jacks than box-style -  http://www.smallbear-electronics.mybigcommerce.com/1-4-in-mono-enclosed-switchcraft-111x/ .  All you have to do is assure that the spring-leaf portion that makes contact with the plug tip doesn't touch the adjacent one and you're OK.

4) Initially, I was using the black plastic-shaft 9mm pots, because they're cheap.  I would epoxy the chassis to the underside of the enclosure.  But I find it a bit of a nuisance.  far better to spend a bit more and get one of the metal-shaft pots with the retainer nut, and use that to stabilize the circuit board.  If you need more controls, black plastic-shaft ones can be used in addition, without needing to drill absolutely perfectly-placed holes.  This weekend, build #4 will be a FET preamp with volume/treble/bass pots, and two of those little micro push-button switches like you're seeing on more MXR mini pedals.

5) 1/8W resistors, small ceramic caps, and SIP op-amps help a lot in making for small compact layouts.  I know some folks turn their nose up at ceramic caps, but jeez, it's rock and roll, folks.  You're not making a recording studio mic preamp for your $2000 Neuman, folks.

6) Plan, plan, plan, and as the saying goes "measure twice, cut once".

[jonboper]

Here's a link to the pics of my "micro-muff" 
http://www.diystompboxes.com/smfforum/index.php?topic=64752.msg1105423#msg1105423

Would it have been a problem if the lugs on those pots were touching the enclosure? looks close...

[Ben Lyman]

Here's a link to the pics of my "micro-muff" 
http://www.diystompboxes.com/smfforum/index.php?topic=64752.msg1105423#msg1105423

Would it have been a problem if the lugs on those pots were touching the enclosure? looks close...

Yes! that would've been no good. The exception is if a lug were going to ground anyway, like the 1st lug of a volume pot will usually go straight to ground for example. On this build, I had to make careful measurements to make sure the pots were precise. I also use the anti-rotation tabs to make sure there is no way they will move when I tighten the nuts. Some people go all out and shape the tabs with files or shape the holes into rectangles, or drill halfway and shape the tab to fit the divot, etc. I simply drill a 7/64" hole for the tab and call it a day.

[jonboper]

Wow. Intense measuring. I'm not even sure exactly where to measure from, or how, when it's all outside the box and not hooked up...well done man.

[thomasha]

I like to use illustrator, but sometimes even a pdf editor is enough.
Mostly I use it for faceplates, but sometimes there are some pedals that require some extra planning>





Here is the file I use to play around>


Here some picture of small pedals with a different configuration>



and with the open jacks>



cloudscapes also posted a good image, which helps when testing the position of the pots.
Here>


more information here>
http://www.diystompboxes.com/smfforum/index.php?topic=101299.0

[Ben Lyman]

one way is with some calipers, measure the diameter of the pot, 16mm so the middle is 8mm.
measure the thickness of the enclosure wall, about 2mm.
add them for a total of 10mm,
now from the top of the enclosure, measuring in from one side go 11mm and it should just clear the inside edge of the enclosure with about 1mm to spare.
Of course this is all just an example, don't trust my figures but try it for yourself and see how it goes

[EBK]

In addition to calipers, I'll often use a small machinist square when I'm measuring.

[Cozybuilder]

I'm working on my first a 1590a build and am having a really hard time getting things to fit. Especially with the mono jacks, it's difficult.

My question is about whether anything can be touching...I'm assuming the tips and sleeves cannot be touching anything - either the tip/sleeve of opposite jack OR the enclosure itself...is this correct? Is there anything else I need to be worried about making accidental connections?

(I was making a Temple of Giants but that didn't fit. I changed it to an OK which should fit.)

Hadn't seen the schematic for the Temple of Giants before, found it here: http://www.grindcustomsfx.com/wp-content/uploads/2017/05/TempleOfGiants.pdf

Its pretty much a straight forward silicon fuzz face with switchable diode clippers, just a single knob. This is a circuit you could fit in a 1590LB, a 1590A will have tons of room.

[Cozybuilder]

Good advice from Mark above. In addition:

2) 2.1mm power jacks come in two flavours: innies (secured by a nut inside the chassis) and outies (secured by a nut on the threaded collet outside the chassis).  Innies lie pretty flush with the outside of the enclosure, but at the cost of taking up a lot more space inside.  ONLY USE OUTIES.  If you install the power jack at the rear skirt, and can bend the solder tabs to the side without breaking them, then the little space between the two chassis screws can be used efficiently without taking up valuable real estate.

3) Open jacks, like these - http://www.smallbear-electronics.mybigcommerce.com/1-4-in-mono-switchcraft-11/ - allow for closer spacing of jacks than box-style -  http://www.smallbear-electronics.mybigcommerce.com/1-4-in-mono-enclosed-switchcraft-111x/ .  All you have to do is assure that the spring-leaf portion that makes contact with the plug tip doesn't touch the adjacent one and you're OK.

5) 1/8W resistors, small ceramic caps, and SIP op-amps help a lot in making for small compact layouts.  I know some folks turn their nose up at ceramic caps, but jeez, it's rock and roll, folks.  You're not making a recording studio mic preamp for your $2000 Neuman, folks.

6) Plan, plan, plan, and as the saying goes "measure twice, cut once".

2: There are 2 flavors of innies: the switched and non-switched variety. Use non-switched for small box builds unless you are using a 9V battery in the box too (there are some who have done that in 1590A)
Small Bear (SKU: 0661G), BLMS (Thinline 2.1mm DC power jack), and Tayda (SKU: A-991) supply them.

3: Another good choice on open frame jacks is Lumberg, they are smaller than the Neutrik and Switchcraft jacks. Available from Small Bear & BLMS.

5: ⅛ watt resistors can be found at Mouser in about any value you think you might need. Check them also for small ceramic caps- 0.1" lead spacing, this gives you a lot more flexibility in designing your layout.

6: Use dial calipers to measure thickness of walls while planning the hard-parts layout. Don't forget to consider how the circuit card will be mounted so that it stays in place without shorting on other components in the box. I typically mount all the hardware first (pots, any toggle switches, I-O-Power jacks, stomp switch, and LED. Then fit the card in on standoffs, using JB Weld to attach them to the box. After all that, then I design the circuit card so that all components on it fit without interference with the hardware in the box.

Good luck, you'll find small box building is not that difficult if you take the time to plan things out first.

[davent]

Check out Madbeans 1590a (Babyboards) build guide. Lots of good info on layout and parts selection. Bean is around on this forum.

A note on resistors, i've found resistors up to a 1w rating in the same size as the 1/8w so check the datasheets, you're not limited to 1/8w to get them in a very small size.

http://www.madbeanpedals.com/downloads/BabyBoardGuide.pdf

dave

[Mark Hammer]

Hadn't seen the schematic for the Temple of Giants before, found it here: http://www.grindcustomsfx.com/wp-content/uploads/2017/05/TempleOfGiants.pdf

Its pretty much a straight forward silicon fuzz face with switchable diode clippers, just a single knob. This is a circuit you could fit in a 1590LB, a 1590A will have tons of room.

Actually, not a Fuzz Face derivative from what I can see,  Really more related to the Knight-Allied Fuzz, an early commercial DIY kit.

[MaxPower]

Holy hell those things are small. I stack two altoids tins for my small projects. Place the pots, switches, and jacks on the top tin and the circuit & battery in the bottom compartment.

[jonboper]

This is a circuit you could fit in a 1590LB, a 1590A will have tons of room.

Yeah, maybe if I'd drilled the box more carefully...but.

A lot of great information here, and some great resources. Really appreciate the product information too, helpful to be pointed in the right direction. You all are nuts with some of these little builds - I didn't think it would be as difficult as it has been...the great curve.

[Mark Hammer]

I received a request from a local player the other day for a loop selector in a 1590A package.  The quarter twist was that he wanted a second DC jack; a "power-thru" outlet, if you will.  By mounting the stompswitch just a tad off center, I had enough space to install a second DC jack to the side of it.  The power to feed the LED comes inthrough the rear skirt, as it does on many same-sized pedals, and can be fed to other parts of the pedalboard by exitting the left side of the stomp (he wanted the selector for engaging a wah off the board to the right).

[rankot]

I have one question - what to do with vinyl washers? I usually put them outside, but they look a bit ugly. Why using them, anyway? To reduce switching mechanical noise, or some other reason? What happens if it is put inside the box? 

[Mark Hammer]

The white ones?

They prevent scratching of the surface of the enclosure when tightening or lossening the retaining nut.  The limited height of a 1590A enclosure means that placing such a washer inside will raise the height of the solder lugs inside such that you may not be able to close the lid without shorting them.

If you don't like the look of the washer, leave it out.  Just be careful with how you put the retaining nut on.

[Ben Lyman]

BLMS has metal washers (hardware store probably does too)
http://www.bitcheslovemyswitches.com/#!/Metal-Footswitch-Washer-BAG-OF-10/p/26629491/category=5027572