Alice Mic Build

[ballpein]

So I got lucky and scored a couple Alice kits from Scodiddly, after somebody else bailed on their purchase (thanks, whoever you are).



Scott packs a mean kit. You've gotta respect a guy who goes for genuine Ziploc brand bags.



The more diy stuff I do, the more I realize that the hard part isn't building the stuff, but sourcing parts - so it's pretty great that Scott goes to the trouble of putting these kits together. He even includes the shrink tube.

[ballpein]

Here's the 1" copper tube with the handy template applied.



Unless you count fashioning an emergency hash pipe out of an empty beer can, I haven't done anything like metalwork since 9th grade shop class. I wasn't any good at it then, and there's no reason to think I've gotten better in the intervening twenty years. Scott's notes advise practicing on scraps before doing the actual cutting, which was pretty good advice. I picked up a few pieces of 3/4" coupling from the plumbing section of my local hardware store and cut them to bits before tackling the 1" tube supplied with the kit. I've looked in a few hardware stores now and, while they all carry lengths of 1/2 and 3/4 inch copper tubing, none of them have stocked 1".



It's a little tricky to get a perfectly straight cut, and the corners are a little tricky - I managed to botch one corner on each of the tubes. A quiet voice was telling me to drill the corners out before cutting, but I think I was a little drunk on the power of Dremel. At any rate, I was just happy that I didn't totally destroy them.

There's a lot of copper dust involved in this step, so definitely wear the eye protection. I wish I would have worn a dust mask, too - I probably inhaled about a half gram of copper.




By the way, King Tubby was the soundtrack for the first night's work, and I highly recommend a little dub for any DIY. I'll have to put Trevor's mix on my ipod so I can listen to that in the shop.

[ballpein]

Here's what they look like after a little filing and sanding. I decided to embrace the crudeness of my metal work, and went with a mottled / burnished treatment for the tubes.




The one on the left is the first one I did... I decided to try a bevel on the cutout, and got a little carried away with the filing, until eventually I realized I wasn't improving anything, just filing - I think this might have been caused by the same sort of phenomena that leads to women with drawn-on eyebrows.

The second tube (on the right) I barely filed at all, just enough to take off the sharp edges. I'll give them both another going over before I laquer them.



In Vancouver a while back, it was all the rage for crackheads to sneak onto construction sights at night and strip all the copper pipe out of a building, to be hawked at the salvage yard. Just think of all the mics they could have made.

[ballpein]

At this point, I'm giving myself a C- on the metal work. Next up, I wanted to fit the XLR jacks and drill the screw-holes for them - I figured that would be a no brainer.

The XLR jack nuts don't fit into the tube, so here they are just before having their pointy bits filed off:





The corners file down pretty easily. I think I have a real knack for crudely filing stuff. Some day I should try my hand at grinding.

[ballpein]

now to put the pieces together.



I found out the hard way that the washer doesn't fit the tube. Naturally, I was tempted to file it down, but opted instead to simply do without the washer.

That little PVC collar is a very tight fit. I couldn't think of any effective way to smash it into place with a hammer, so I had to settle for threading it onto the jack.



There's probably a way to do this without chewing up the jack with the vice, but by this point I'm too hopped up on copper dust to care. But don't worry, I can quit any time I want.

[littlesongs]

Great work so far! Scodiddly makes the coolest little condensers. I agree that using genuine Ziploc shows that he cares enough to send the very best. In all seriousness, I keep swearing to myself that someday I will get an Alice or Audrey. It is really cool to see the process unfold.

I think you are spot on about the penciled eyebrows theory too.

[Scodiddly]

Looks pretty good so far, actually. Doing the metalwork is one of my favorite parts.

[ballpein]

Thanks for the encouragement, fellas. I am enjoying this build so far, the metalwork is actually pretty enjoyable. My problem is that I'm a) inept with most mechanical tools and b) a perfectionist - so building stuff can be pretty frustrating for me.

Anyways - when I left off I was putting the XLR jack assembly together, like so:



Note the washer: Scott's notes explicitly state that it won't fit into the mic body, and even if you hadn't read the notes you'd know it just from looking. I had read the notes and I still tried to put it together with the washer. Moments like that make me feel like a chimp in a lab experiment.

So, off with the washer and - dang, still no fit. The PVC collar is a little too big to fit comfortably into the tube. I decided I'd come back to that bit later on.

[ballpein]

Next I drilled the holes for the screws which will mount the XLR jack. I went with a 3/32" bit.





And then a 13/64" bit for the countersink - not a very pro way to do it, I know, and the screw head doesn't actually sit flush, but close enough. My shop is uninsulated and unheated, and it's a couple degrees below freezing right now - so after an hour or two in the shop, my perfectionism gives way to my discomfort, and I wind up making compromises... and then rushing things. And then stuff like this happens:

[ballpein]

Luckily I was alone at this point, because what I said right then would have been offensive to gay people, women, and dogs - for starters - and I'm pretty sure I took the name of at least 2 major deities in vain. This is the part of the experiment where the chimp gets sick of trying to stick the square peg into the round hole, and starts flinging pooh instead.

The perfectionist in me wanted to scrap this body and start a new one. The cold, cranky, monkey-ish side of me wanted to just drill a new hole, eat a banana, and call it a day.

Then I remembered Dad's ol' soldering kit:



I figured I'd just fill the hole with solder, sand it down and start a new hole. Plumbers solder this stuff all the time, right? I felt like a very clever monkey indeed. Plus, the Weller packaging says "expert" right on it, so how could I go wrong?

Well, it turns out that 5 inches of copper tube makes for a damned efficient heatsink. Even Dad's trusty Weller wasn't going to get this job done. I was almost back to flinging pooh when I found the answer, right there in front of me:



Fire! Great blasting jets of it! Suddenly this build had gotten much awesomer. Soon I had this:



and eventually this, which I'm pretty darn happy with, all things considered:

[Scodiddly]

Hmm... the PVC rings I made for the kits seem to fit the XLR just fine, but are a bit too big for the copper pipe! Should be possible to sand them down to fit (a snug fit is best), but if anybody with a recent kit can't get that to work I'll come up with replacements.

[Scodiddly]

OK! I figured out the "plastic ring doesn't fit" problem. The rings are roughly the same, maybe a little thicker wall so it's harder to fit onto the XLR. But the real issue is that the copper pipe is a bit different, also a thicker wall so it's got a smaller inside diameter. Not much, but when I was comparing to a scrap of the previous batch I could see it. So the plastic ring as it comes won't fit.

It should be possible to sand down the ring to fit, since the XLR will fit easily enough. If anybody with a recent kit has too much difficult with this let me know and we'll figure something out. I've got to build a few mics out of this pipe too (already did the metalwork) so I'll be dealing with this too. Oh, and similar situation with the wooden plug.

[ballpein]

Wasn't too tough to get the rings to fit, I gently trimmed them down with fine grit sanding collar on a dremel. One came out perfect, the other now fits a little loose - I'm hoping the copper tape will fix that, if not I'll have to build it up a bit which shouldn't be a big deal. I'll have to sand the wooden plugs down next.

I plan to post a bunch more pictures this weekend, and hopefully I'll have the mics completed by then too. In the mean time, here's a couple questions for Scott:

- your notes mention applying lacquer to the fet and 1G resistor area - is the idea just to sort of seal the fet and resistor themselves?

- I've managed to replace one of those tiny little screws - can you offer any leads on where to source a replacement? I'm striking out all over the place right now.

[Scodiddly]

1. I use the lacquer over the FET and 1G resistor to seal out moisture. With an impedance in that range a warm moist breath can cause the mic to stop working.

2. I've been buying the screws at the local big Ace Hardware stores. It's something like a #2 wood screw, the smallest they have. Then I use the Dremel to cut off the tip.

[cdixon6]

That's a pretty bitchin' mic. I built the Austin ribbon using a copper pipe. I sand blasted it though and clear coated it. It looks nice, and it offers a little cover up on any minor grinder flubs. The only problem I had was finding a fitting that looked good on the bottom and I like the way yours looks. Mine is just a pipe fitting with a chassis mount xlr on it.