Power jack question

[GuitarPix]

Okay - I realize this is probably a total noob question, but I've been searching for days and haven't found an answer to this problem I'm  having.

I built my first pedal - a fuzz box - a while ago and got it to run and sounded okay. I had it running with a battery and all was fine. However I decided that since all my other pedals are running off a power supply, I'd put in a power jack - which I went out and bought. It didn't work. Take the jack out of the case and it does work - then it hit me, positive to the sleeve, negative to the tip. So the power was running through all the ground points.

All my other pedals have plastic power jacks which would insulate from the case.

What should I be doing? Do I need to buy different jacks for power? (I have a bag full of the metal ones.) Or am I imagining this issue and it's actually something else?

[R.G.]

What should I be doing?

The pedal "industry" has standardized on 5.5mm/2.1mm DC connectors, with the center negative. This apparently dates back to when Boss introduced their AC/DC adapters and used that convention, possibly made opposite to what you'd expect to prevent generic supplies from being used.

What you need to do is decide whether you want or need compatibility with the power jacks of the other 99.9999999% of all pedals and power supplies. If you don't, you can do whatever you want. But if you do -

Do I need to buy different jacks for power?

Yes, you need different jacks.

(I have a bag full of the metal ones.)

Bummer.

Or am I imagining this issue and it's actually something else?

Nope, you're not imagining it. It's real. Snags pretty much everyone when they first confront it.

[GuitarPix]

Thanks for the reply. Alrighty then, where might I find the 'right' kind of power jacks? I haven't found anything useful locally.

[Ben Lyman]

def this:
http://smallbear-electronics.mybigcommerce.com/2-1-mm-all-plastic-round/#PhotoSwipe1444929940536

[peterg]

....or this one if you are not using a battery snap:

http://smallbear-electronics.mybigcommerce.com/dc-power-jack-all-plastic-unswitched/

[Granny Gremlin]

You don't need different jacks; you just need insulation.  This can be a pain.  I had a bag of metal power jacks from before I was making pedals and the things I tried were:

- drill out the chassis hole a bit large and paint it (inside and outside enclosure as well as the inside of the hole) with laquer or nail polish to insulate (let dry for 48 hours before mounting the jack
- use powdercoated enclosures (still need to insulate inside the drilled hole)
- those 3 ring binder paper hole fixer thingers (if the paper rips at the hole, those stickers to fix/reinforce) work well and even take care of the inside of the chassis hole; the hole in the sticker is too big for the jack, so put it over the chassis hole and squish it in. Do the same from the other side and it's pretty well insulated)

Usually I will iuse a combo of some of the above.

But I have since bought other jacks specifically for pedal builds.  I don't like those round plastic dc jacks most people use (linked above)  because once you solder it up, you can't remove the circuit from the enclosure without cutting the wires or desoldering which just seems stupid to me.  So I use these:

http://smallbear-electronics.mybigcommerce.com/2-1-mm-plastic-round-external-nut/

Same thing but the nut is on the outside.

[hymenoptera]

I don't like those round plastic dc jacks most people use (linked above)  because once you solder it up, you can't remove the circuit from the enclosure without cutting the wires or desoldering which just seems stupid to me.  So I use these:

http://smallbear-electronics.mybigcommerce.com/2-1-mm-plastic-round-external-nut/

Same thing but the nut is on the outside.

I'm really liking these. Only problem is they stick out really far and don't look as good, so I'm thinking I need some washers or another nut on the inside to space them back into the enclosure a bit.

Still though, being able to solder them up and still be able to disassemble for painting is a nice touch. I recommend these "external nut" ones.

[nosamiam]

I don't like those round plastic dc jacks most people use (linked above)  because once you solder it up, you can't remove the circuit from the enclosure without cutting the wires or desoldering which just seems stupid to me.  So I use these:

http://smallbear-electronics.mybigcommerce.com/2-1-mm-plastic-round-external-nut/

Same thing but the nut is on the outside.

I'm really liking these. Only problem is they stick out really far and don't look as good, so I'm thinking I need some washers or another nut on the inside to space them back into the enclosure a bit.

Still though, being able to solder them up and still be able to disassemble for painting is a nice touch. I recommend these "external nut" ones.

I've done that with the extra nut. Looks pretty pro.

[Granny Gremlin]

I'm really liking these. Only problem is they stick out really far and don't look as good, so I'm thinking I need some washers or another nut on the inside to space them back into the enclosure a bit.

Still though, being able to solder them up and still be able to disassemble for painting is a nice touch. I recommend these "external nut" ones.

You can take up the space on the inside with whatever random washers you have lying around.

Personally I like how it is outside like a bellybutton - makes it easier to squish things into a smaller box sometimes.

[Cozybuilder]

You can use one of those white washers that come with stomp switches if you need to keep most of the jack outside the box, I think the appearance is good for some pedals:

[davent]

Small Bear at one time had a tutorial where the power jack hole was drilled out quite oversize, filled and leveled with Bondo then redrilled, 'jack-size' through the Bondo for an insulated hole.

Outer nut jacks? Used 1/8" aluminum plate to lower the protrusion through a chassis.

[Granny Gremlin]

Small Bear at one time had a tutorial where the power jack hole was drilled out quite oversize, filled and leveled with Bondo then redrilled, 'jack-size' through the Bondo for an insulated hole.

My lord, what a righteous pain.  I know that stuff is used for auto body repair, but I would not trust it on a stress point like that. It's mean to fill dents so they can be smothed over and painted (not structural), but here there's nothing holding it in except the product's own adhesion.  Spidey sense says bad idea.

One thing I forgot to mention above was instead of nail polish (though everyone should have some of that around - awesome for guitar finish touchups) there is an actual thing called "brush on electrical tape"  or "Liquid Electrical Tape" etc depending on the brand.  That stuff is great (just don't use the included brush).

[duck_arse]

I like to space those over-long barrels back into the innards with a (usually) styrene plate of some description. think opical drive blanking plate in a tower pc. and you can use the plate as a mounting bracket for "other things", if it happens to have a bit of right-angle to it.

but I hate those fecking nuts, I've NEVER managed to put one on the jack, in or out of a build, without the nut cross-treading enough to jamb, first try, most second tries.

[davent]

but I hate those fecking nuts, I've NEVER managed to put one on the jack, in or out of a build, without the nut cross-treading enough to jamb, first try, most second tries.

My understanding is it's especially probematic with  a certain supplier of said jacks. I've got mess of 'Mode' branded ones ordered in error and never an issue with the threading or anything else with them.

dave

[GuitarPix]

Thanks for all the great replies.

[Granny Gremlin]

You don't need different jacks; you just need insulation.  This can be a pain.  I had a bag of metal power jacks from before I was making pedals and the things I tried were:

- drill out the chassis hole a bit large and paint it (inside and outside enclosure as well as the inside of the hole) with laquer or nail polish to insulate (let dry for 48 hours before mounting the jack
- use powdercoated enclosures (still need to insulate inside the drilled hole)
- those 3 ring binder paper hole fixer thingers (if the paper rips at the hole, those stickers to fix/reinforce) work well and even take care of the inside of the chassis hole; the hole in the sticker is too small for the jack, so put it over the chassis hole and squish it in. Do the same from the other side and it's pretty well insulated)

Usually I will iuse a combo of some of the above.

But I have since bought other jacks specifically for pedal builds.  I don't like those round plastic dc jacks most people use (linked above)  because once you solder it up, you can't remove the circuit from the enclosure without cutting the wires or desoldering which just seems stupid to me.  So I use these:

http://smallbear-electronics.mybigcommerce.com/2-1-mm-plastic-round-external-nut/

Same thing but the nut is on the outside.