Friday, March 17, 2023

a material handling incident Wile Coyote would have recognized

  So there I was*, minding my own business in my shop, making a lifting rig for my rotary table, so I can hoist it to and from my mill's table with ease and safety...

 For a while now, said rotary table has been sitting on a wheeled cart, on top of a random steel framedingus to bring it to a convenient height, all just so I can move the damned thing around the shop easily.  note: the top of the cart has carpet on it.  (former bell cart)

 The steel framus is just a random leftover, roughly cubic, from something I once took apart.
note that it is smooth(ish) and painted on top.
note that the bottom of the rotary is very smooth indeed... and it leaks oil.
  (ooh! foreshadowing!)

 Said cart was in my way, so I gave it a shove with one foot.  A hard shove, since there's some two hundred pounds total mass there.  To my astonishment and horror, the cart moved smartly as intended, the cubical framatron went with it as intended, and the rotary stayed put in mid-air for a split instant (because Newton was a savage motherfucker, shit must have been wild before he invented inertia) then succumbed to gravity and fell to the remaining top of the cart.

 It did not hit the cement floor and break (cuz cast iron, cuz!) and it did not touch my foot.  My ancestors were looking out for me this morning.

 I moved the cart to take the picture, but everything on it remained where it was after the incident (and will remain there - the rotary at least - until the paint has dried on the second half of the lifting sling I was making).  The gizmoframe was shifted by the table coming down at an angle.  No toes were harmed in the making of this safety film.

 Speaking of lifting slings; the reason I was making a lifting sling is that I have (temporarily, until the hoist cart is built) rigged a hoist over one end of the mill table, enabling me to get the 59kg / 130lb beast up and down without hurting my back.  So far so good.  But the table has long rods for handles, 11.5cm / 4.5in long.  Putting a chain sling or hooks on these and lifting is dangerously unstable.

 Maybe I've spent too much time as a Texas Tank Watcher, but the "correct" solution seemed obvious: make a custom lifting rig which solidly prevents shifting and makes for a clean, level lift.  This we then do.  I finished the first half a few days ago.  Fabbing the second hook took only a few hours early this morning, followed by primer.  I will be show it in use when the paint is dry.

 This is a typical pattern of fabrication for me whenever I need to make more than one of something (unless I have drawings and am doing precision or interchangeable parts); I complete one to figure out how, then I make #2 - #N, subtracting any mistakes I made on the first one.

EDIT: action shot:





* 'there I was' indicates this is a 'war story'. If it were it a fairy tale, it would begin with "once upon a time."

Tuesday, March 7, 2023

blog colors changed

 by popular request, I've changed the default blog colors to eye-searing black text on bright white background.

 I'll just have to make it look the way I need for my light-sensitive vampire eyeballs, using DarkReader.  Hmph.

temperature control system for 3D printer enclosure

 The Problem:

 My 3D printer is in a basement room which, in the winter months, stays well below reasonable printing temperatures. The house is literally 115 years old, so fixing the room temp isn't going to happen.

 The First Half of the Solution:

 Fortunately, a very good friend gave me a heat-resistant 3DP enclosure.  The printer alone dissipates over two hundred watts between the bed heat, hotend, and motor drivers.  So I measured temps after the printer had been in "preheat" mode for 30min, and it plateaued just below where I needed to be, while the room temp was on the "high" side of its low range.  Well poop. 

 My tent needed a heater, but obviously if I just stuck a small heater in there, there would be nothing to stop the temperature from climbing so high it cooked the printer's electronics.  It was time to consider a proper temperature control.

 The first bit of good news is that I've done this sort of thing before so I already knew how easy it really is.  It's just a matter of buying a few Commercial Off The Shelf parts and connecting them together with a few simple screw terminal connections.  Usually, you don't even need to solder.

Complete kits containing the PID controller, a "solid state relay", and a heat sink can be found online for under $30, so I did that because I was broke and cost had to trump quality this time.

  (for the reason 'SSR' is in quotes, please see this Big Clive video, in which he tears down an identical unit)

 So it's a fake SSR in the strictest sense, a sense we don't care too much about, but the screw holding the thermopad / TO220 style device inside to the back plate was literally sticking out of the heat sink surface! I had to file and sand all of that flat to get a good mate to the all-too-thin Chinesium heat sink.

 Fortunately, the thing has astonishingly low forward drop compared to the devices I am used to; it didn't get warm at all under a 20A load, and the device is nominally rated to 40A.  I flatly did not believe that number before I tested it... but it might be possible!  In any case, the load for this application is only 2.5 amps.

 The next item I needed was an enclosure.  Because I needed to preserve as much desktop real estate as I could, I decided I wanted a deep enclosure with a small front panel.  After poking around the usual places, I was astonished to find that I couldn't find one to buy at any price, so I decided to make one.

 A quick review of available materials and a bit of brainstorming assisted by a bowl of the finest Longbottom Weed, I realized a scrap of extrusion which has been knocking around my shop for literally decades had finally found its final fate. All I had to do was cut it in half, patch up a bunch of ugly holes, mill a bunch of not-ugly ventilation slots, oh and figure out how to attach the two cut halves to each other in a permanent and durable way, without being able to weld aluminum.  Visions of Rosy The Riveter, hashtag 'we can do this'.

 This we then do.


  I drilled matching holes in the thicker bits where the two halves would meet, epoxied little aluminum pins into the holes, applied epoxy to the roughened edges, and "glued" the two halves together. 

 When done, I lacked confidence in those pins and their small surface areas, so I added three machined 'clips' and epoxied those to the inside, around the thick edges.  NOW I am semi-confident that the two pieces will remain one piece... provided nobody drops it.  I wish I had thought to take a picture of them before I painted everything black but I didn't so there it is.

 Next I needed a front panel for the controller and a power switch, and a back panel for power entry module, fan and heater output receptacles, and thermocouple input terminals.  That effort looked like this:

Blogger won't let me put multiple photographs on the same line, isn't that amazing?

 The back panel was a bigger PITA than the front, because it had more fiddly holes in it, but nobody sees it.  

 The front panel needs to look good, but it's only got two big square holes and the four small panel mounting holes.

 I have to assume this extrusion was intended for making things like this.

 I decided to make the front panel unnecessarily thick, so I could unnecessarily counterbore the panel screws and use socket-head cap screws for added sexiness.

 This is why some of my simple projects take a long time, but I was motivated to do a better job than I usually would (for myself) because I planned to blog about it here, and I didn't want to embarrass myself.

Fiddly, fiddly. Measure thrice, cut once.

 At least with the front and back panels, if I scrapped one, I could replace it.  That wasn't true for the enclosure halves, and I was tense about that a few times when I was cutting on them.


Milling thin materials - or rather, fixturing thin materials so you aren't also milling your machine's table... can be interesting.

 I saw no reason to put much effort into the finish of the back panel, so I just ran it over a convolute wheel on the buffer a few times.

 Then came paint.  On a lark, I decided to coat it with Rustoleum™ texture paint (rattle-can).  I bought it with my employee discount at the store where I work.  This won't be an endorsement, nor a condemnation, because while I like the finish, Rustoleum seems to have a problem with their cans; since they now spray in any orientation, it's not possible to clear the nozzle & valve per the instructions still printed on the can.  

 As a consequence, you can get two, maybe three spraying sessions out of a can before the valve clogs.

"image enlarged to show texture"
( for scale, that's a countersunk hole for a #10 screw )

 Seriously, this stuff has a lovely appearance and feel, at least for my aesthetics.  The feel / texture is not "rough" in that it does not drag against the skin the way, say, sandpaper might, as the peaks are not sharp, but it is noticeable.

 The character of the texture changes somewhat with additional coats.  I did a few tests on other bits of aluminum, and it adheres under abuse, and once baked on with heat (always do this if you can) it becomes quite scratch and abuse-resistance, as much as any paint I suppose, but I think the texture helps to hide marks.

 I could have hidden the seam lines in the enclosure using epoxy or bondo and a bunch of sanding and/or milling... when I got to  that decision point in the project, it seemed like a lot of additional work, and I decided to try to reign in my OCD at that point to save myself much frustration, and remind myself of the wisdom of Voltaire: "Perfect is the enemy of Good".

Ze Back Panel.

 The controller can use either T/C or RTD input, and I have brought both out to terminals on the back panel.

 Ground wire is connected to the shield of the T/C cable.

 Yes, there is a missing screw. We don't talk about the missing screw. That was a Very Bad Day.


 The controller is the auto-tuning PID sort, very easy to use if you are patient and follow the instructions.

 It's not as easy to use as an Omega, but an Omega is $200 whereas this thing cost me $20 including a SSR and heat sink.

 Sometimes Chinesium wins. :(

haha, wut? (awful eBay advertisement - more real posts coming soon)

You could be forgiven for not knowing what the hell is being sold here...

1. The newest embedded square LCD display table headers, so that the sewing machine looks more compact, avoiding accidental collision damage to the table header, voltage direct intuitive reflect. More detailed shell process for aluminum panel drawing process, more stylish, shiny appearance. Internal process on all models more excellence, this is definitely a good partner Hi-Fi.

2. 3000W strong load power, together with its two-inductor-current filter, can easily bring all kinds of HiFi, AV equipment, 27 to 50-inch large color TV, three shots projection, LCD rear projection, high-power amplifier and various theater equipment. 
3. Made of imported high-quality components common mode, differential mode AC power supply filter, with surge surge absorption, l ightning, the current automatic circuit overload protection. Analog output with professional-level AC voltage meter header, filter output at any time direct the level of AC voltage 220V to audiophile level of the output voltage will be adjusted to your sound system the best audio and visual effects. 
4. Filter internal material examination: imported power cable, shielded metal in fever-Germany-jamming WIMA MKP capacitors, German professional filter capacitor. 16A surcharge short-circuit protection. 
5. Innovative ground, the line (FireWire) automatically detect whether the circuit that can detect your wall outlet is grounded, zero line and the line (FireWire) is reversed, and indicated on the dial.

Got it figured out yet?  Perhaps this photograph will help.

Yeah, it's a power line filter.

And you know what?  People are gonna buy the hell out of it because it looks sexy and buyers are ignorant.

Monday, January 2, 2023

my slow progress isn't all on me- I've had help!

 "This package is delayed due to severe weather in the delivery network."

 Nah, horseshit Amazon; this package was delayed because you had it right here in Denver, but instead of dropping it at my house, you sent it to a ski resort sixty miles west of here, up in the mountains, and then you had to send it back to Denver.  Well done, Amazon.  Golf clap.

 So now you say it is "expected" by today.  Expected by who??

 And this shit has been constant.

ex: I have a major network upgrade for the garage, my shop, and my wife's office which is held up for lack of a $5 wall-wart and a $3 conduit nipple which I have to drive out to the 'burbs to purchase.

ex: I broke off a tap in a piece of work which is essentially irreplaceable, so I spent eight or ten man-hours trying unsuccessfully to remove it, and I had to buy another tap before I could finish the other holes.

 My slow progress (on anything worth blogging about, at least) has not been held up by the lack of big expensive items or by serious back injuries or meteor strikes.  No, progress has been glacial because of an endless parade of seemingly trivial yet effective setbacks.  I don't know why the gods wish me to fail, but it's clear that they do.


 PS: on an unrelated note, I wanted to point out another reason for the rarity of my posts: I'm trying to only post about what I myself am actually doing.  I'm trying NOT to post "helpful hints" about topics of interest which can be found all over the net.

 So for example, I won't post about how to stop a Raspberry Pi from fighting with a Creality 3DP control board, because that's well documented and _I_ am catching up in that regard, I'm doing nothing different there.

 However, I absolutely am blogging about the temperature control system I've made for my printer's enclosure, and will eventually do a proper write-up with entirely too many pictures, because:
A) I haven't found anyone else doing that, anywhere, not even on the Creality discord
B) It might actually be useful to other people who need to run their printer in a too-cool room
C) Making a fancy (heating only) temperature control system is much, much, easier than one might think, and does not require an EE degree to do, with today's readily available and inexpensive parts.

 That sort of thing might actually be worth typing up a long windy document, not to mention wrasslin' with Blogger's primitive image-handling. :)

Sunday, January 1, 2023

I have not forgotten about my blog...

 I've just been really, really, busy, and I've been forced to prioritize my free time.

 I have loads of pictures I need to upload to this clunky, obsolete platform through its clunky, obsolete web interface... and I've been telling myself pictures are worth a thousand words, so I have been waiting to upload the pics and therefore not writing any words. 

current efforts:

1. moisture extraction system for air compressor
2. The 'Surgical Style' Work Light

(3D printing)
1. a metal housing for the electronic parts of the
    temperature control system I designed for the
    printer's environmental enclosure
2. finishing setup of an OctoPrint (R-Pi) & webcam,
    just waiting on a longer camera cable now
3. new all-metal heatbreak, currently waiting for it to
4. waiting for 5VDC isolator connector to arrive
    (for USB connection between Raspberry Pi & Ender 3V2)


 For the moment, I am more focused on the 3DP efforts than the shop stuff because frankly, it's just more interesting.

 Plus, I've had the printer up and dialed in to what's considered "good enough" for most people (judging from other people's calcubes, benchies, etc) and various minor upgrades and work on the work area have kept the printer from running for a while now, so I'm pretty eager to wrap up this upgrade session and go back to printing to see how much difference the upgrades (mainly the heatbreak and controled-temperature tent) will make on my prints.

 Funny thing about 3D printing: it takes a long time.  So if you're really into it, keeping the printer up and actually printing is important.  So that's been chaffing at me; I got stuff I wanna MAKE!

 Secondarily, if you're a noob like me, and/or you're not made of money, knowing that the currently running print is still, yanno, printing, and not making spaghettini, is a pretty big deal.  I don't want to leave a print looking good, go to work, and come home nine hours later to find that it all went to hell five minutes after I walked out the door, and I've just wasted a pound of filament -- oh wait I've already done that once. 

So... I'm really looking forward to having the webcam available, assuming I can convince myself that the camera and printer controls can be placed on the web without compromising the security of my home network... I haven't made up my mind about that yet.

And that's where I'm at.  Pictures and more words to follow when I get another moment.

Monday, October 24, 2022

Inkzall™ markers are no joke (an uncompensated endorsement)

 This is an unsolicited plug for Milwaukee brand InkZall™ markers, which arrived on the market making two promises:

#1, the marks won't fade (I'm testing that in the sun vs. a Sharpie right this very minute - but it'll take a few weeks/months)

#2, they will make a permanent mark on almost all hard-to-mark surfaces which give other products trouble, the classic example being oily / greasy metal.

 So far I have tested Inkzall markers on oily metal fresh from the mill, rusty metal (not fresh) from the scrap yard, glass, and silicone rubber.

 I stopped there, because I ran out of surfaces which I've ever had trouble marking with a Sharpie, and the Inkzall does all of them.

 In all fairness, some markers do glass just fine namely, most solvent-based markers.  I've seen loads of markers that make clear marks on glass.

Wax was the one surface I thought would be hardest to make a clean, non-beading mark on.  Guess not... yeah, I couldn't remember the name of the markers - it has worn off of the two that I have when I made the photo...

 There is one other little feature of interest to those who wear hard hats: the marker's clip was designed specifically to clip onto the brim of a hard had neatly.

  Of course, the extra performance doesn't come for free: these things run about five dollars apiece, which is I think somewhere around twice the price of Sharpies. 

 I think they're impressive, but I probably wouldn't be using them if not for the fact I can get them at a discount. :)

Sunday, September 4, 2022

catching up, Part Two, Episode Nine, Book Six Rides Again...

Mr. Prongy over there is what one does when one needs to solder four brass bearing surfaces to the inside of a square tube.

(As soon as you heat the tube to install the next one, one or more of the others melt and fall off or move.)

Using a shop-made tool†, the procedure is merely slightly fiddly:

  1. generously tin 4 inside surfaces
  2. generously tin the bottoms of 4 brass bearings
  3. using your preternatural manual dexterity, place all four bearings in place, using the tool to hold them.
      (note: the author lies, he soldered two of them in place first before he realized he was stuck and would need a tool, so now it will be much easier than the above.  -- sincerely, the author's other hemisphere)
  4. apply heat until everything settles into place under spring* pressure

Goddammit,, why are you like this?!?   

 * "springy", LOL, yeah right! This is A36 structural steel, it has forgotten what carbon ever felt like, so good luck actually making it springy, temperoid, hardish, etc. The fingers were springy enough to do the job once I cut them 2X as long as I thought they needed to be...

† took me, oh, 30min of actual labor I suppose - not including a break or three. Not a lot of time for a project taking many man-days of labor

Thursday, July 21, 2022

can't work, can't type

 Having trouble getting started in the shop again, for a variety of reasons including being desperately broke nerve impingement, arthritis, and tendonitis issues, heat, and other domestic problems.

 Can't easily create posts or even use the computer for more than a few minutes at a time, same reasons.

Wednesday, June 22, 2022

well, this is awkward..., which is to say, Google, lied to me.  So here's the thing: this blogging platform provides quite a lot of statistics about visitors to the blog, including per-post granularity.

 And the stats page has been telling me for months that nobody was reading a damned thing I wrote.  So, I felt I was wasting my time.

 So now I have some human feedback telling me that - shock, surprise! - Google's shit is broke here too, just like search, just like YouTube...

 I have plenty of trivia I could write about, but virtually none of it is particularly important or note-worthy, with the possible exception of an upgrade to my surgical-style shop light, which is finally getting the ceiling mount it needs, so that the @#$^)* salvaged Ikea Stolmen post - to which it was formerly attached - can get the hell out of the middle of the shop...

 Well, I'm pleased that anyone is getting anything of value at all out of all this blather.  Both I and my other half are recovering from various hurts, so it may be a while before much more appears here...