Hack Chat Transcript, Part 2

A event log for Microscopy Hack Chat

Let's get small

Dan MaloneyDan Maloney 06/23/2021 at 20:080 Comments

Ahron Wayne12:43 PM
This one?

Dan Maloney12:43 PM
I wasn't going to this time, I swear!

Patrick Hickey12:43 PM
@polyfractal greeting from scotland. I recently salvaged a biorad radiance 2100 confocal, currently trying to source a solid state laser to replace the argon ion laser, any recommendations for a 488nm module supplier?

Ahron Wayne12:44 PM
with "only" 60,000 views and 200 comments, one of whom is applied science guy? :)

polyfractal12:44 PM
yep that one @Ahron Wayne! the results weren't great, but it was a fun project and with some tweaking i think it could work.

And yeah it gained a bunch of traction in the last few months thanks to the big influx of traffic, but it was a "dud" for a very long time which can be demoralizing if you let it get to you :)

polyfractal12:45 PM
@Patrick Hickey oh nice! congrats! afraid I don't have any that come to mind, 488nm is a bit of an oddball wavelength. tbh I do most of my scavenging from ebay too so dont know many real vendors :)

Ahron Wayne12:46 PM
I'll add that one to my watch later then, and it answers my question as to whether you'll turn your attention to metal printing.

polyfractal12:46 PM
is the argon laser dead, or just don't want the hassle of big inefficient gas laser?

Ahron Wayne12:47 PM
If you're actually trying to repair/use the laser Sam's laserfaq is a great source:

polyfractal12:47 PM
@Ahron Wayne heh. I do have some vague plans to work on SLA + nanoparticles + sintering. not quite direct metal printing but roundabout way to get there. ditto to ceramics. Mostly boils down to small enough particles and keeping them colloidal, which usually needs some extra chemistry to work (e.g. alumina will remain suspended in resin if you add some citric acid)

Patrick Hickey12:49 PM
cool, thanks @polyfractal i found a good supplier based in poland “lambdawave” they have many flavours of lasers, arduino controllable and low prices. Hope to connect with you in future! Patrick

polyfractal12:50 PM
related to that old lattice video actually, i'm currently working on some new electroforming projects, building up a really thick deposit on 3D prints for functional reasons. we'll see if it works out for the particular project, but feels underutilized by hobbyists :)

Thomas Shaddack12:50 PM
What resin? I did some research on a now likely dead project with printing resins...

Ahron Wayne12:50 PM
@polyfractal please keep us updated on that. I've been working on bound metal printing with filament for the past few months and there's a huge amount of potential, but I'm especially excited about the idea of working with powders mixed with resin because you might be able to mix your own alloys and also get huge details. One company described SLA-metal powder as "like butter" being spread on the plate which presents its own challenges of course.

Ahron Wayne12:51 PM
@polyfractal You should definitely check out the Virtual Foundry/Bradley woods, he got started with electroforming 3D printing exactly as you're describing before he started manufacturing metal filaments.

polyfractal12:51 PM
@Thomas Shaddack just generic cheap SLA resin so far (elegoo maybe?). Haven't done much work on it yet, just enough to realize that particles either need chemical modification to stay in suspension, or some kind of agitator, or they need to be nano-sized. hit pause on it for a while to work on other projects

Ahron Wayne12:52 PM
There is also some talk in the community about debinding ceramics and other materials and then infiltrating them with metal for composites with no shrink.

polyfractal12:52 PM
ooh interesting, will check out Virtual Foundry!

Thomas Shaddack12:52 PM
I tried some localized thermal laser decomposition of copper oxide in epoxy. it indeed created copper.

Thomas Shaddack12:52 PM
metal matrix composites???

Thomas Shaddack12:53 PM
thought: MMC done by electroforming on carbon fiber.

morgan left  the room.12:53 PM

Ahron Wayne12:53 PM
@polyfractal ++

perlsackhd12:53 PM
@polyfractal microgravity should also avoid separation

Ahron Wayne12:54 PM

Ahron Wayne12:54 PM
The results would also look super cool to scan with your laser doohickey. This is using a conventional USB microscope to scan

polyfractal12:54 PM
haha, now just need to convince Bezos to take me up on his launch :)

Dan Maloney12:55 PM
But he might not be "allowed" back...

Ahron Wayne12:55 PM
One-way trip?

Thomas Shaddack12:55 PM
going to experiment with ar0230 sensor on a raspi. very high sensitivity 2-megapixel camera, datasheet promises a 16-bit raw. may be handy for the spectrum acquisition from the microscope.

polyfractal12:55 PM
@Thomas Shaddack interesting! did you load up the copper oxide into the epoxy yourself or was it a commercial product? Pulsed laser?

Thomas Shaddack12:56 PM
Myself. It was a fairly coarse copper oxide so the result sucked. Handheld 5-watt 450nm blue.

Thomas Shaddack12:56 PM

polyfractal12:56 PM
rad! might give that a shot myself

Thomas Shaddack12:57 PM
Should try acrylate. Burnt epoxy STINKS. The amines, likely...

polyfractal12:57 PM
kinda sorta related, this paper has always intrigued me and I've wanted to try it: tl;dr: coat something in copper, then lase the surface with just enough energy to oxidize the copper selectively

kjansky112:58 PM
Bezos Blue Origin microgravity will only last ~ 3 minutes, I think Elon can do much better.

Thomas Shaddack12:58 PM
Tried if copper on circuitboard could be etched away with nascent iodine from laser decomposition with CO2 laser of iodoform. The board didn't even notice and I stank like an old hospital for next two days.

polyfractal1:00 PM

polyfractal1:00 PM
i really need to get myself a CO2 laser at some point, the wavelength seems super handy to have around the shop

Ahron Wayne1:00 PM
For my goals the problem is avoiding copper oxidation, not causing it... I mean, once you selectively oxidize it, how do you avoid it happening to the rest?

Thomas Shaddack1:00 PM
Todo, same rig, laser soldering. If the beam can melt solder paste with high enough precision.

Thomas Shaddack1:01 PM
Cheapo K40-III. Replace electronics with arduino/Marlin for easy support of gcode, the original software SUCKS.

Thomas Shaddack1:01 PM
Enough to earn the machine the nickname "Blue Horror".

Dan Maloney1:01 PM
So it's 1:00 here, which means we've been at it for an hour now. If Zach needs to get back to work, we'll have to let him go with our thanks. I really enjoyed this chat today, learned a lot. Feel free to stick around and continue the chat, of course -- the channel is always open. Thanks Zach!

Dan Maloney1:02 PM
And thanks to everyone for the great questions, too. Transcript to follow shortly.

polyfractal1:02 PM
@Ahron Wayne yeah, the thought crossed my mind as well :) i figure you'd have to throw some kind of dielectric on top (Al2O3 or photoresist or something) after oxidizing

Ahron Wayne1:02 PM
Got it. And thank you Zach!

polyfractal1:02 PM
Thanks for inviting me @Dan Maloney! was really fun, and i have a list of notes to look into :) I'm good for a few more minutes, but have to jet and take care of my dog in a bit (she just had surgery :( )

Nicolas Tremblay1:03 PM
Thanks Zack. Great chat, learned plenty.