Is it behind the knob in the picture?
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Well…the first two and last two letters are right 
L’s and C’s are so similar anyway 
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Close… I’ve labeled the second knob delay not decay 
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My goal is to 3d print as many of your panels and then make some of my own - do you have a stripboard layout for the 808 Kick handy (pure laziness on my part)
I don’t. The 808 kick was my first attempt at doing a DIY PCB instead of a stripboard.
There’s a schematic, and a “paper PCB” layout from M4TM which I based my build off of, and my PCB…but I’m not aware of a stripboard layout.
No worries! - ill see if I can draw one up tomorrow
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So feeling a little frustrated that my progress has stalled lately. I know it would slow…the pace I dug in at wasn’t sustainable and I fully expected a tapering off. But I haven’t completed a module in 2 weeks…and that was an almost passive multiple. I’ve started a few things and have a couple of things in-progress…
But really I just need a break. Not a break from the synth…but unfortunately a break from the only room I have to work on the synth in. Just feeling burnt out from work and don’t want to spend much leisure time in the room I work at sitting at the computer I work at. Which is kind of extra frustrating because I do want to make hobby progress and that’s the only place in the house I can make that progress.
So, things have been getting ignored and I’ve been catching up on some reading and flattening the couch cushions instead. Unfortunately instead of feeling rested and restored I just feel lazy and like nothing is getting done 
But - work usually slows down a bit in January which should help (the past few weeks have been crazy busy for me.)
I did order myself a new toy to experiment with today though. A vibratory polisher along with a few types of media (ceramic rods, walnut shells, and various grits) to see how it does at finishing SLA printed parts. I’m really curious to see if it can polish things like the sequencer buttons to a nice smooth shine. I’ve been searching for others who’ve tried this for awhile and finding surprisingly little information. But what little I did find looked promising so figured I’ll give it a go. I was originally thinking about just building something like a rock tumbler…but the vibratory polisher seems like a better route so we’ll see how it goes.
I do have a set of @CTorp’s k25 modules on the way…and really want to build his sequential switch I’ve got the boards and all but one component for…and still need to build my @analogoutput modules that have been sitting for FAR too long. I just kind of wanted to fill the new case with only modules I did 100% from scratch…but I already cheated and put the 1222 and some multiples in there because I didn’t want to deal with screwing them into the old case’s wooden rails. So…guess I should just dig in on getting some of these built soon.
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I feel you man, I got burnt out and work was a pain this time of year. Don’t dread lack of progress, just chill and you will get to it.
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I took a building break in 2019 that ended up being 8 months long.
I got over it.
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Happy new year all! - wish everyone the best.
Thought I’d post a pic of progress… mostly has been printing and fitting hardware to plates, although I did manage to build two of @juggles modules from his Github (so far!) 
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So glad to hear what I’ve shared has been helpful @GhostBassist!
I got my vibratory polisher yesterday and have been doing some tests on trying to polish my 3D printed knobs/buttons and such.
The polisher I got is the cheapest I could find on Amazon…and it’s designed for cleaning brass for ammunition reloading. It has rather large warnings not to use it with water or you’ll void the warranty. Oh well. I didn’t expect to use the warranty anyway
And the bowl is completely sealed so I don’t see much risk of using it with water. All the same I gave it a go with the suggested walnut husks it was designed for first. As I expected it was a bit loud to leave running in the house. So it got put outside. Also as I expected the walnut husks did almost nothing. The instructions say 30-60 minutes should completely clean brass…but 4 hours did almost nothing for SLA or PLA printed parts. Well…not exactly nothing…it did do a great job of getting tiny bits of walnut husk all but irrevocably embedded into any small openings.
While that was running I printed a cone to go in the center of the bowl. See…most vibratory polishers have a torus shaped bowl…but this one is pretty much just a bowl. And a lot of the reviews suggested putting a 5" funnel in the middle to get better action. Instead of a funnel I 3D printed an insert that screwed onto the center post and had curving sides to encourage better circulation of the media. It also fills a bunch of space so I can use less media with my small parts. A quick test with the walnut husks seemed promising and they did seem to get better circulation with the insert.
And it turns out the bag of ceramic rods I got isn’t really enough for the bowl on this machine. So good thing the insert takes up a bunch of space…with it installed the rods are just barely enough to be usable.
The one website I found with someone actually using this process on SLA parts they just use the ceramic rods with a constant flow of water. I can’t really rig up the constant flow of water on mine…and I did want to use some polishing compound anyway. So I gave it a go with some 400 grit “pre-polish” first to see how it would do. At first I had way too much water…but after doing more research learned you just want enough water to get the grit to stick to things - you don’t want the parts and media floating. So I got that adjusted and let it go for 4 hours.
The results…were…not stunning…but noticable. Which is about what I expected from 400 grit.
All of those had 4 hours in the grit. Only the PLA printed wheel on the left is really noticeably changed with the slightly scuffed looking surface. The box in the back also is significantly less shiny. The small knobs/buttons/standoffs feel smoother…but don’t look that much different. I’ve sanded SLA parts with 300 grit sandpaper before and this is about the same finish…so more or less what I expected.
But let’s take a slightly closer look.
That’s unprocessed on the left and processed on the right. You can see how the processed one is more even and has less visible layer lines. If you look closely you can also see the edges are softer - look at the top up close - instead of sharp edges it’s all just kind of smoothed over.
But - the embossed lettering still stayed crisp. So that’s nice. I did do a test one one were I had already filled the letters and the filling did stay in and the staining on the outside of the part was mostly removed. But…it also did discolor the filling a bit. So…not quite perfect.
This time I flipped them - processed on the left unprocessed on teh right. It’s hard to tell but the processed one is more even - look for the moiré looking patterns on the top from the layers.
It shows up better if I moisten them to show how they’d look with some clear coat:
You can see the left one is more even and the faint layer lines aren’t as noticeable.
The PLA part the processing removed most of the texture from my textured print bed:
You can still see some shiny spots which is all that’s left…but the “layer” lines from the extruder are now very visible while originally they were completely obscured by the texture.
So - not major changes. But I wasn’t expecting them with 400 grit.
Right now it’s out there running with 1200 grit polishing compound and has been going for almost 2 hours. So in another 2-3 hours we’ll see it’s doing. I did check on it about 10 minutes ago and it did seem like the parts were starting to take a bit of polish so I’m really curious to see how this does.
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Having problems visualizing your polishing set up. Do you have a pic? I was considering using my old rock tumbler for some prints. I’ve used it to clean old guitar parts.
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If I had one I’d have included it…but I keep forgetting to take one 
Since you asked nicely though…
And inside:
Those are the ceramic rods. For rock polishing they’re considered non-abrasive and are apparently just there to fill space and help the grit move around. But for plastic parts they’re abrasive enough they can apparently do quite a bit of smoothing by themselves.
However - as you can see…they don’t fill the bowl on this polisher enough. So larger parts don’t stay under. It should be filled just about to the top of the white insert I added in the middle. (which if you look closely you can see is starting to come apart from the vibrations already…Guess I need to make it a bit beefier around the threads next time.)
And here’s a little video of the action:
Again…the bowl shape and not having enough ceramic has the action not quite working how it should. It should be more of a torus movement with the outside coming up and going in towards the center. But I’m getting more of a circular motion right now which isn’t as efficient. But…you can see some of the small pieces get lifted up and out then pulled back in.
Oh - and while taking these I checked a few parts…and it does seem that the 1200 is polishing. Hard to tell if they’re actually shiny or not without rinsing them off…but they’re definitely getting smoother. Still need another hour or two before I pull the plug though.
This one from harbor Freight is only $12 more than I paid…and looks like it’s more of the design I should have gone with. And they have it (and ceramic media) in stock at my local store too. So I may go up and pick one up if this test proves at all beneficial. https://www.harborfreight.com/5-lb-metal-vibrator-tumbler-67617.html Reviews on it are a bit mixed with a number of people complaining about it not holding up…but…sounds like they’re doing rocks which need to process for days not plastic which can process in a few hours. So my use is fairly light duty compared to what most people seem to use them for.
If nothing else I figure with the walnut husks it will be nice for cleaning bolts and other hardware from time to time.
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at first, i thought you had a laundry basket with huge 3d printed buttons.
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That little “Laundry basket” is actually a case I designed for a MMDVM hotspot for digital radio 
It’s just a little pi zero with a digital modem “hat” - I originally FDM printed the case (the one in the photo here) but then re-printed it with the SLA when I first got the SLA printers and was experimenting with seeing how it would work for functional prints.
First I just re-printed the little lens over the array of LED’s. Then I did the lid…and finally decided to try doing the whole case.
I just don’t “get” digital radio though. It’s nice that it’s super clear…but the whole “radio” part feels redundant. Radio that can’t work without an internet connection and only uses RF for a link of a few hundred feet just doesn’t feel like radio to me. And most of the talkgroups I found were pretty toxic - it was like all the bad things of FM repeaters only with a worldwide audience instead of local. So that gear has mostly been collecting dust. I pretty much stick to HF now when I need my radio fix.
Anyway. Back to the polishing. I did pull things out last night and there’s definitely polishing happening! I didn’t get to any photos last night because…well…I was just too tired and didn’t feel like bothering with photos. Plus…it’s really hard to show the difference at this point. After 4 hours with the 1200 grit things are definitely starting to polish and not just wear down. But the difference is very subtle and hard to show. This is the best photo I could get showing the difference:
On the left is after 4-5 hours of 1200 grit. On the right is unprocessed.
You can see how much smoother the top is. But…what’s harder to show in the photo is that the inner surfaces inside the knurling are still very rough. I think my ceramic rods are just too bit for the level of detail I’m trying to achieve. I’m half tempted to try breaking them into smaller pieces to see if I can and if that will work better. Or maybe trying the walnut husks with grit/water though I’m not sure how well they’d deal with water.
It really seems that the grit does determine the smoothness - but the filler material determines how small of a surface can get smoothed. The buttons seem similar - but are harder to show in a photo. They’re starting to get a glossy sheen to them…but tighter areas like where the shoulder meets the sides aren’t. So I may need to find some smaller ceramics to make this work well. I’m also tempted to print a new bowl for the vibrator that has more of a torus shape and is smaller so it will work better with less media and fit my needs better.
I tried to do the moistened comparison as well…but can’t really because the smooth one is now so smooth water won’t sit evenly on it anymore and just beads up I’m curious to see how it would look with a few coats of urethane at this point. I suspect I’d get very nice very clear results.
But I want to keep experimenting and try to find a setup that will get into those little nooks and crannies before I go that far.
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Gave in an ordered some smaller ceramic media…but Amazon is apparently hurting from the holiday rush so it won’t be here until Sunday.
In the meantime I did an experiment with some walnut husks and adding some nufinish car polish to them. It definitely shined up the already polished knob even further:
I only have the one polished knob so for before/after you’ll have to compare to the photo above. But it’s much slicker. Unfortunately even with the liquid polish added the husks left a lot of dust in the less polished parts. And after a run through the ultrasonic cleaner to get that off the part is pretty much back to looking like it did before the nufinish.
But it’s still a much more finished looking part after the various polishing steps.
Since I had the husks in there with polishing compound I decided to try them on something more along what they’re suggested for. So I dug into my parts big and grabbed the nastiest most corroded brass, copper, and steel fittings I could find:
And after about 5 hours in the husks:
Not bad at all. Yeah…I could do a lot better with a wire wheel on my dremel or a bench grinder but this took basically zero effort and I’m a big fan of zero effort
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So…I think November was the last time I actually finished a module. And yeah…I have two that just need some jacks and pots wired up. But…I need something simple to get me back in.
So…a k25 attenuator it is - doesn’t get much simpler than this:
And it works. Though…something is definitely up with my synth tonight…horrible buzzing sound coming in from somewhere. The new pup knocked my audio interface around a bit this afternoon so wonder if something isn’t fully plugged in or if some knobs got bumped…will look into that later. Pretty sure it is the interface since it persisted even after I unplugged the synth itself
Anyway, also of possible interest. I have this air quality sensor I’ve been working on the past month sitting on the desk next to my main desk. And all day it’s been reading in the 3-6 range for PM 1.0, PM 2.5 and PM10. Which I’ve found is actually a bit high for my house…usually I’m in the 0-3 range. This may again be thanks to the new pup
But…what is worth sharing…soldering just this simple little module…shot those numbers up to the mid teens for PM 1.0 30’s-40’s for PM 2.5 and 40’s to 60’s for PM 10! And not just while I was soldering. I finished soldering about 30 minutes ago and the numbers are STILL up…they’ve come down a bit…but right now I’m still seeing 13/25/30
So…I ordered a cheap fume extractor from Amazon…will be interesting to see if it actually helps or not.
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Well, I was going to try and finish another K25 module or two tonight…but I can’t quite get to my resistors:
Can’t play with the modular either because the power cords are behind him.
Guess it’s a lazy youtube night
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So…I bought the cheapest “Solder fume extractor” on Amazon for $25. There were other more expensive ones but they didn’t look like they were any more effective. They had bigger fancier cases…but they all used the same ineffective looking “Activated Charcoal Filter” pads. So rather than than buy the fancier ones it seemed the cheap one would be just as effective.
Basically it’s just a standard 110v muffin fan with a grill on it that holds the filter pad in place. You can also see my PM sensor in the background (The little silver box next to the roll of blue tape.)
And at first glance it appears to work well. It’s a bit loud…but tolerable. And soldering about 5" to the right of it where I usually do it easily pulls all the visible smoke away from my iron and no visible smoke comes out the back!
But…The little PM sensor sitting back there tells a different story.
Before firing up the iron I was seeing values of 0-3 for all the sizes of PM. After:
Yeah…that’s the same kind of jump I see without it.
Now I admit the fan is blowing right at the sensor. But…I don’t think it really matters that much…if the filter was effectively removing the fine particles from the solder smoke then it should be fine to blow that exhaust right at it.
So…the filter does remove something since there’s no visible smoke coming out…but it doesn’t remove the fine particles that can really cause lung irritation. It may help by at least blowing them away from your face. But it’s definitely not cleaning the air. I’ll try again tonight with the sensor further away to see how numbers in the room do overall.
Using that same sensor on my 3D printer was interesting as well. Since I have a partial enclosure around my printer I wasn’t that surprised that printing didn’t really register any difference on the sensor about 5 feet away. My enclosure goes around the 4 sides of the printer…but I keep it open at the top unless I’m printing ABS or something that really needs to keep the heat in.
When I put the sensor at the bottom of the enclosure inside with the printer numbers also seemed about the same. But when I put it at the top of the enclosure above the printer…they went up. Not that much though when printing with PLA. Only in the 6-10 range which is no worse than what I see when I cook dinner two rooms away.
But for solder fumes…going to take something a bit fancier than the $25 Amazon special…
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