DIY API 1604 inspired mixer (16x8x2)

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That is an incredible amount of work and persistence.  I’m very impressed.  This is real DIY.  Years of effort.  The meters look great.  VU with a micro for Visual light Reinforcement logic.  The frame you show seems different from the original 3 bank frame.  Beautiful!
 
The frame you show seems different from the original 3 bank frame.
First off, can't say thanks enough Faze;  from going out and copying your original schemas for me, to taking pictures of your channels, sharing your vintage API desk experiences,  plus all the other helpful replies to questions... cornerstone, my friend.

Frame remains the same...Just missing patch section and misc bezel/trim pieces.  Everything has to be stripped and re-painted since flash flood last year ruined powder, and seller no longer makes color. :/  Cutting and shaping the last of the trim pieces this weekend, hopefully!

Now you understand why the Eurorack system uses a pair of extrusions to support back planes. Building a console is a tremendous learning experience. Keep at it!
Yes sir, lol....I see now!  Trial by  :eek:"doh!!!":eek:

Again, thanks everyone for your support and kind words. Really helps right now, during metalwork, which has a fun-factor I put right below trips to the dentist.

 
Thanks Echo.

Today's unfun work:

Stripping old color:
HXTrQC3.jpg


Etching prep for powder
PK2e7xl.jpg


Examples of how varied finish can turn out depending on prep, cure time, etc.
wuQSOIF.jpg


Getting some orange peel finish. Not sure if toaster has insufficient heat, or timing's off.  IR gun measurements showed piece temperatures well below what the stove analog thermometer was showing, so I'm perplexed.  ???
Q2yWHbT.jpg

 
As with most things, it's an art.  Application sheet is rather vague.  Powder wants 400F for 10min--not ambient temp-- material temp, which is hard to determine with crappy IR gun.

Prep is 80%:
Shape piece, 800 grit sand, followed-up with optional 1200, dish soap clean, acetone clean, etch (phosphoric acid or walnut sandblast), distilled water clean, acetone clean, preheat 400deg  for 5-10min to outgas metal (basecoat only).  For topcoat, pieces need minimal handling and should be done shortly after basecoat.

20% is application:  low psi, dial-in cfm, set voltage, hook conductivity, and 'intuit' substrate thickness uniformity with gun passes vs cloud density and distance to part.  I'm still learning. Practice makes perfect.

https://www.youtube.com/watch?v=45gKVb12LGI

Edit: Notice in above vid, the top bar farthest from cam has least topcoat, and therefore shows most blue among all pieces.
Might appear subtle in vid, but that color grade is the goal.

jPbn1qD.jpg

 
boji said:
Thanks Wb. No, went the hard way.  Melanite template and a 1/2hp laminate router. 3-fin carbide flush cut with lower bearing guide, and yep!-- I went through a few of them.

That’s impressive. Do you have any photos of that setup?

I use lacing twine instead of cable ties. I use it kind of like cable ties. I just wrap it around the wire bundle where I want and tie. To do the classic look down the length of the wire bundle you really need  to plan in advance and have a jig. Doing it on the fly doesn’t work very well which is why I do it the way I do.

 
Do you have any photos of that [hackaday milling]?
Hi Gold. Photos are sitting on a old HD somewhere... :/

Thinking about it again, forgot I made a master metal template from melanite template, which I just dug up.  Melanite is still needed for sandwich safety gap (I'll show/explain later).
Because I was surprised how well it worked, I'll have to simulate it for you in a photo, which I wanted to do anyway for photoblog.

Some mistakes while learning: 
Gently approach metal in direction opposite bit rotation or you get runaway or chatter (perhaps obvious).
Do not attempt to cut excess material off and get flush cut at the same time.  This is not like a milling bit, not at all.
Use cutoff wheel / angle grinder to cut up to 1/4" of material near template, then use router to flush metal to template pattern.  Too much feed, too much metal, and you get massive, scary kickbacks. Mock-up to follow.


[Wirelacing] on the fly doesn’t work very well which is why I do it the way I do.
Yes, very hard to make perfect! Totally see how a jig would help. The thought of tying two dozen simple ring knots feels like ...cheating... but I'll give it a try on few remaining that are not yet laced.  Thanks!
 
boji said:
Some mistakes while learning: 
Too much feed, too much metal, and you get massive, scary kickbacks. Mock-up to follow.

That's what I'm scared of. I have a Bosch Colt 1HP router. When I fired it up it was a little too close to a bucking bronco for my taste. I'm sure with some practice I can get better results.

I've been using this:
https://www.grizzly.com/products/Grizzly-4-1-2-Mini-Track-Saw-Super-Kit/T27444?gclid=EAIaIQobChMIxv6Lg8qa6AIVm4FaBR0GqwyVEAQYAiABEgIVU_D_BwE
to cut off excess metal. I use cutoff wheels for short length cuts. This saw is great for cutting off longer pieces. It's relatively cheap and it's built very well. One of the best tool purchases I've made.
 
Ok good news. As it turns out I have to mill 1/8" off some fader 'cheeks' to make room for 1.5" x 8 fader metal.  I'll do a vid.
y0FFUfv.jpg

6bPylVj.jpg


When I fired it up it was a little too close to a bucking bronco for my taste.
Yes, understood. It's more like painting and brush strokes, only in reverse.  :)

Edit: As with most things, the prep helps. If there's only a leading edge of say, 1/8"-1/4" of aluminum hanging off the template, then once you've dug down to template, put preloaded pressure on the bearing and the routers plate while slowly moving forward on the template. 'Brush away' from material with oval-like motion if and when rpm dips too low or you hear an inkling of chatter developing.  It's a sound thing too.  "Wax on, wax off"
 
How I did sides:

After drawing a few ideas, I settled on this shape, which I carefully cut, filed, and sanded as straight to the eye as possible.
WAFrGfq.jpg


Then I made a 'master template' out of metal, using the melanite. (You'll just have to imagine the bit is in the router)  ::)
4zwgvsD.jpg

6q5JUh3.jpg


Once I had master template, I used melanite as insert between metal template and next piece of aluminum stock. This allowed for a safe gap between guide bearing and cutting bit:
3OUEk1M.jpg


cUlyxaU.jpg


These are the tri-carbide bits I used.  Not cheap, but available from your local home despot.  :(  Went through 2 and a half of them. (C'est' la vie)  First one I blew out bearing cause...learning.  Learned I could cut through about 25 feet of aluminum before bit started to give out and kick like a mule.  The slower and more patience I had, the longer the blade lasted.  There's some zen lesson in there somewhere. Did it all dry, so imagine cutting oil would have helped lower blade temps and prolonged bit life.
oVrQ688.jpg
 
Thanks! I guess I set it up wrong from go. I've never used a router before so I'm flying blind. I didn't use a template or a guide bearing. That setup looks like it would be much more stable. I just put the router away after trying it because it seemed scary dangerous.
 
boji said:
These are the tri-carbide bits I used.  Not cheap, but available from your local home despot.  :(  Went through 2 and a half of them. (C'est' la vie)  First one I blew out bearing cause...learning.  Learned I could cut through about 25 feet of aluminum before bit started to give out and kick like a mule.  The slower and more patience I had, the longer the blade lasted.  There's some zen lesson in there somewhere. Did it all dry, so imagine cutting oil would have helped lower blade temps and prolonged bit life.

We used to use slow turns and lubricate with very small amount of oil mixed with high % alcohol for aluminium when I was in school. Our teachers knew their stuff.

 
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