I ran into a problem where one of my Pi's that has not been used in months, would not connect to my WiFi.  I found the issue was in the octopi-wpa-supplicant.txt file (which can be found when installing the microSD from the printer in a PC and browsing the files there.  For some reason I had not added the key_mgmt field (in bold below), but everything else was set correctly.  When I fix that, it worked again.  I know this Pi had worked when it was last used so it's strange that the line was missing, but in any case it's fixed now.

This is the entry from octopi-wpa-supplicant.txt that I updated on the MicroSD ( done from my PC using Notepad++, but notepad works too ):

## WPA/WPA2 secured
network={
  ssid="YOURNETWORKNAME"
  psk="YOURPassword"
  key_mgmt=WPA-PSK
}

Some other commands I found helpful to see what WiFi was doing are below (I used these while I had the Pi connected via wired Ethernet and ssh'ed in using Putty):

ifconfig -a
iwconfig
iwlist wlan0 scan | grep ESSID:

The last one clued me into the problem since I could see my network, but it was not connecting.

While I was ssh'ed into the Pi, I took the opportunity to run these as well (the 2nd one takes several minutes to complete):

sudo apt-get update
sudo apt-get upgrade

Then I rebooted and updated Octopi itself (from the browser, login to Octoprint, click the wrench at the top left, select "Software Update" and then click "Update All").  After that and blowing the dust off this neglected Pi, it's back in working order.

Pools are great, when they work, and a huge pain when they don't.  Recently my Dad's pool has been having several issues including a worn water rotor (replaced some parts), blown start capacitor (replaced), leaky seal between the pump and impeller assembly (replaced the gasket and lubed it up), and then a cracked coupler between the filter and backwash valve (repaired - hopefully). 

That last one has been the biggest problem, and forced me to (eventually) empty the filter of sand and re-level the base in order to get it to line up with the backwash valve (which is actually called a "Vari-Flow Assembly").  The problem was that the coupler had cracked (see pic below) and started to separate.  Ideally I would replace the coupler, however it seems that it is not possible to replace the coupler without replacing the valve (or finding the correct offset parts for the valve), since the coupler is a captive nut.  The reason the coupler cracked in the first place was due to the filter slab and filter being out of level (so the filter was pulling away from the valve). 

To "fix" the coupler I glued it back together using superglue, and time will tell if it will crack again or not (but it was clamped for 2 days to cure and the crack was clean so it was a best case for superglue to work).  Due to the issue with the slab though, it would surely crack again if I forced it together, so I had to level the slab.  My dad, remembering back to when he helped out with the Great Pyramid of Giza, suggested using a lever (specifically a 2x4 or 2x6), which was a decent idea, but due to the close quarters, not workable.  So I recalled seeing some 300 lb air wedges at Harbor Freight, and thought they could work, but I wanted to get some with the largest capacity possible.  I bought these air wegdes  (which have a 500 lb capacity), and they did the job.

My method was to clear some space for the air wedges to slip under the slab (or pavers under the slab in this case) and then pump them up evenly.  They become very tough to pump when they start getting to the limits, and I certainly pushed them since, although the filter was drained of water, it was still full of sand at the time).  It would be cool if they made these air bags with a schrader valve so I could pump them using my bike pump though, the bulb design worked OK, and is probably used since it's self limiting (hard to blow out the bag when the bulb would probably go first).  To jack the slab using the air wedges, I had to  wedge some large rocks under the base as I went, and pounded them in with a hammer, then pumped the shims up and wedged again with rocks, and pumped the shims some more, till the base was level. Then I backfilled under the slab with large rocks and sand and packed them in, before releasing the pressure and removing the bags and backfilling some more. 

I know that sucks, and I will probably regret not getting some actual concrete mix to fill the void, but as you can see in the pics, it was late, and I was in a bit of a rush to try and wrap it up.  I'm sure the pool gods will punish my laziness when I have to come back and pour a slab for this damn thing (hopefully in the off season), and probably replace the "Vari-Flow Assembly" as well.  But the pool gods did get one good laugh at my expense, since I ended up having to remove some sand in order to re-position the filter - after I had leveled the slab with all the sand (but no water).  I should have emptied it to start and it would have been much easier to level the slab, but this is my stoopid stuff lol. 

Below are some pics I took during my recent work on this pool filter mess.  The first pic shows the cracked coupler before it was glued back together (it was not fully cracked).  I'll just mention that the brown start capacitor shown in the pics was mounted on the back of the pump under the back cover, and the sliver run capacitor was under it's own cover mounted laterally on the top of the motor (the run capacitor was OK, but the brown start capacitor was dead).  And since I mentioned the capacitors, I'll also just say that folks gotta be very careful with capacitors.  Capacitors generally and especially large ones, like the ones in the pool pump motor, hold a dangerous charge even when they are disconnected, so they must be fully discharged before handling them.  I don't suggest messing with capacitors unless you know what you are doing.

This site is not abandoned, I have just been extra busy for the past couple months.  My Dad busted his hip and I have been helping him out, so most of my free time was spent assisting him.  He is doing a bit better but it's a slow recovery.  My Job has also become much more stressful with cuts and such, but fortunately they have been understanding on the few times I have had to take time off to help my Dad. 

With all the crap going on in the world right now though, I feel lucky that's the worst myself and my family have to deal with.  Reading whats happening in Ukraine makes me thankful that my family lives in a country which is not being threatened by the genocidal forces of Mordor, and is in fact supporting those who are.  Along those lines, if you live in the USA, and want to help get the ball rolling on more sustainable aid for Ukraine, please consider contacting your Representative and ask them to get a new Lend Lease Act for Ukraine moving so it can be voted on.  You can also find a list of companies and brands that are exiting Russia, and those that aren't as well, at the link here (some that are sticking with Russia will probably surprise you).

As for the content here, I'm gonna try and get my 3D printing and modeling hobbies back on track.  I expect that updates will be slower than my normal productivity, since I am still assisting my Dad.  There are a few new projects I have in mind though, which I will be posting as they develop.

I have been noticing that the flow calibrations have been coming out inconsistent on my CR10S Pro. This started after (though not directly after) some big changes to the machine including a changeover to a BMG (clone) direct drive (and updated the firmware to Tinymachines 7.4.3 for the CR10S Pro V2), so I decided to re-check my e-steps.  When I originally set it up, it was right on at E=415, but for some reason it is now all over the place.

I initially screwed up my e-steps calculation.  Since I was overextruding I had it in my mind that esteps would go down which normally they should in that case, but due to the problem I'm having (where nothing made sense) the numbers I had from the tests would have me increasing e-steps.  In any case my esteps and the values when extruding 100mm are all over the place.

So I took apart the BMG and found the first problem:

The first pic shows the gear which is installed backwards.  I flipped it around so the full depth of the teeth could engage on the nylon gear of the BMG extruder.  However that did not fix the problem...

So I removed the extruder, cleaned everything, and set it up so the hot end would be removed from the path.  Then I made sure everything was tight (especially the tensioner), and ran filament through several times.  The results were slightly more consistent but still not right.  I found that I could stop the filament from moving by holding onto it, though the extruder did not click or complain, and the stepper shaft did not stall or miss a step - which means the gears are not biting strongly enough on the filament.  I cranked the tensioner as far as I could turn it easily and tried again, but I can still stall the filament by hand.  I'm guessing that the tollerances in the BMG clone are just not quite there and there must be either a misalignment or a gap possibly.  I checked over the gear alignment as best I could with the gate swung open and it seems OK though.  

So now I least I know that this is not a problem with the stepper, vref for the e-stepper and probably not the e-steps.  It looks like a problem with the extruder which is allowing the filament to slip.

I dug further into the extruder and next found this, which I overlooked the first time I had it apart (and apparently also missed it when I put it together initially):

It's hard to see but there is no grub screw in there.  This gear was held in place only by the compression of the bearing and the gear pressing on it, which was not much.  I'm kicking myself for not seeing this when I installed the BMG, but I recall that this part was "assembled" when I got the stepper so I'm guessing the grub screw was never there in the first place (I did not find one loose in the assembly either).  I was fortunately able to steal one from an unused stepper and get this working again, but feel especially stoopid for missing not one but tow problems during the initial build of the stepper.  In my defense though, my eyes are not what they used to be :D

I did have to adjust the esteps again, and starting over from 415steps/mm which is the default for the BMG, I eventually landed on 421 steps/mm.  That was at least a consistent value, which I confirmed with two tests that both hit on exactly 100mm when I requested 100mm from the stepper/extruder. 

So although really dum, this was a success, and maybe even more so considering I actually have some really nice prints from the printer, even with the screwed up extruder.  That was until recently at least, when I tried to run PETG and noted the inconsistent extrusion and flow values (which I track using a Google Sheet).  I was also seeing issues with wild retraction settings when checking hatchbox wood previously (a post I will update to point here as a likely cause of that problem). 

This is a screw together coupler for a Bowden Tube, to allow it to be opened at some midpoint.  It is a work in progress right now but 90% there.  Once this is done, I may integrate a runnout sensor into it.

Update 2/8/2022 - I wrapped up the design on this today and it's gonna get posted later this week.  It uses a TPU insert to help seal the connection between the Bowden Tubes.  I don't know how "sealed" it is but I thought "why not" since I have the TPU.  I will also post a version that does not require the insert though.

Update 2/11/2022: This is now posted on Prusa here:

www.prusaprinters.org/prints/132363-bowden-tube-coupler-using-pc4-m10-pneumatic-fittin

No, I have nothing against traditional Dutch footwear, its the clogs which jam up my printer when I do something dum that I dun' like.  In this case I know what happened, I had been messing with retraction, and ramped it up to a higher than normal value when I was testing the Hatchbox wood PLA using my BMG direct drive.  I think I must have left the retraction high when I went to print something else using regular PLA, and that must have sucked some plastic into the colder part of the heatbreak. 

I was getting prints that looked like sponges so I pulled the nozzle off and removed the heatbreak. The clog can be seen in the pic above, it almost looks like the end of a PTFE tube in a non-all metal hot end, but don't be fooled, its a nasty clog, and has to be removed to get the printer working again.  To dislodge the clog, I used the blunt end of a 1/16" drill bit bit to push it out with the block removed (with the heatbreak installed but the nozzle removed), and heated to 180°C.  Once at temp, with the plastic softened, I pushed the drill bit through a couple times to evict the clog.  After that I took the opportunity to swap in a plated MK8 (brass) 0.6mm nozzle which looks like it will work nicely.

As soon as I saw that PrusaPrinters was running a quick contest to design a pen, I knew exactly what I would design if I entered it.  The design would be a pen with a mm ruler, a gauge for several sizes of metric nuts and bolts, a 4mm bit holder and finally a pen :D  I thought that a pen like that would be useful for folks who do a lot of printing or designing things to 3D print.  I didn't think I would be able to get it designed though, before the deadline for entry. 

But then I had some free time this afternoon, and thought I would take a swing at it.  Unfortunately what seems simple usually (for me) evolves into something not so simple, and so a project I though would take an hour took multiple hours - and I have still yet to print and test it.  I am pretty happy with the sliced model though, and once my Ender3 is freed up tomorrow I will try and print it.  If it all checks out, the design will be uploaded to PrusaPrinters and entered in their contest for some filament.  It is designed to use a simple pen insert which I pulled out of a BIC pen.

I took some of the inspiration for this from another handy tool I use pretty often, which is a remix of this thing.  If you need to sort a lot of nuts and bolts, that is a great tool and makes the process easier than just guessing.

UPDATE 2/4/2022 - I did a pretty comprehensive redesign of the pen after testing it.  I thought I would not like the triangular profile but since it is rounded off and tapers, it was not a problem.  I extended the profile (and the ruler) the full length of the pen, and added a magnet to the cap, and have another version with a 10x5x1 magnet that can be glued to the body of the pen (however I don't have these magnets so it will remain an untested remix once I post this).  The pen is also a bit thicker but still normal sized and should be comfortable to write with. 

Getting the fit to work with the pen refill and the 4mm bit was probably the most difficult part of this design.  I printed a half dozen test parts to get it just right - and I hope it will work similarly for other printers.  Getting tolerances right is a big pain with FDM since not everyone's printer/slicer behaves the same, and when dealing with very small close fitting parts it makes it a bit of a balancing act to try to make things work.  My printers are not perfect so that adds to the headaches.  I try to calibrate things when running test prints like these though, to limit the problems.  In any case I hope it will work as well for other folks as it did for me.  I am running a final test print now and will post it with some pics probably later today or tomorrow, once those are done.

Update 2/5/2022 - It's posted on Prusa Printers and entered in their Pens and Pencils Contest!

https://www.prusaprinters.org/prints/129703-multi-function-pen-with-a-metric-ruler-nut-and-scr

Update 2/6/2022 - I made a minor change to the design to allow the pen refill to be installed easier.  It's not a big deal but I felt like it took too much force to install the pen refill and so the updated model (updated on PrusaPrinters), has a modification to add a slight chamfer to the hole, and it was very slightly widened overall.  I printed another one using the new model and it works perfectly so that should be it for changes.

NOTE - SEE UPDATE FROM 2/11/2022 BELOW.

I have been using a bit of wood PLA lately and really like Amolen Dark Wood PLA which uses walnut, and also Hatchbox Wood PLA, which is lighter in color.  Both these print well, even with a 0.4mm nozzle on my ender3, and both have made some really nice prints.  I recently picked up a couple of spools of Hatchbox wood, and noted that there is quite a bit of oozing on these new spools, which I had not noticed in the past.  I normally run less than 1mm of retraction on my direct drive converted CR10S Pro, however with the Hatchbox I have found that I need to raise that quite a bit.  I have gone to 5mm, but still have significant stringing and blobs.  I just tried 6mm and it looks like that may do it, but I will try increasing the retraction speed to see if it's any better.  I have lowered the temps (to 205°C) and speeds (to 40mm/s) previously, and dropped flow (to 90%), and plan to tweak the extra prime once I get the retraction to where it looks OK.  I'm also running these tests with coasting turned off, but will tweak that after everything else is optimized as best I can get it with my printer.  I'm really interested to see if the combination of an aggressive retraction to reduce the blobs, combined with some extra prime to get things restarted after a reaction may work for a filament that is really oozy like the Hatchbox seems to be in my printer.

The Hatchbox almost seems like a foaming PLA with the way it oozes, but I have never used those before so cannot really compare.  I don't recall that happening in the past but I also did not have a camera on the nozzle to see happening live so cannot be sure.  The models I have been printing with wood PLA have not been a good test for retraction either, so they may have hidden the oozing issue.  I'm primarily interested in reducing the z-seam in my prints, since that is what my models will show the most (stringing is less of an issue).  The Hatchbox does seem to be forgiving when dropping flow however, and even though the pics show what looks like a rough surface, it is actually very consistent when viewed normally. I still think Hatchbox wood is one of the best for wood filaments, so it's worth the effort to try and get it looking as best it can. 

Update 2/3/2022 - Well I printed about 20 of these things and a few of my test cubes once I had the settings down.  I ended up by turning the flow down a bit (89%) and went with 4.5mm @ 45mm/sec for the retraction using my BMG direct drive.  I did not need to use the "Extra Prime" fortunately.  When I tested with it, it only caused more stringing with no noticeable benefit to the seams.  I'm not happy with the seams still but I gotta actually print something sometime, and found the best middle ground for stringing and seams that I could at this point.  If I figure something else out I will update here, but for now this is gonna be it.  

Update 2/11/2022 - I found a major problem with my BMG extruder (a grub screw was missing from one gear), so this was all for nothing, but the problem is at least fixed now.

I need some way to store my growing collection of flex steel build plates for my CR10S Pro, so I designed the thing above.  It looked cool I thought, and should store several plates safely.  I even thought that maybe with the 0.6mm nozzle I could get it down to a reasonable amount of time (I told myself).  Well I probably knew I was lying to myself if I thought this print could go under a day, but I rolled the dice, and Cura popped up a day, 19 hours and 1 minute to print that beauty.  It will also take half a kilo of material, so I'm gonna pass. 

But this experience did give me some ideas on a more modular approach to this problem, which would take a more reasonable amount of time to print (each part).  Hopefully I can get rid of all the supports too and give it a nice surface finish.  So it's back to the drawing board, since I'm not into multi-day (or even full day) prints for various reasons.

Update - I couldn't leave this alone and re-designed it from the ground up.  I'm thinking I may be able to cut down on the print time further, but the longest plate in this model (the base which has a lot of solid areas) will take about 12 hours, while the leaves are about 6 hours each.  I think it can probably be cut down further since I can boot the speed since it is flat. 

I'm still not sure though if I will tackle this print since it will take several days and I already have things going on, but will add this to the list.  I need to get a safe storage solution for my build plates though...

I saw that PrusaPrinters has a contest going to design a button.  I was looking through the rules and then this just popped into my head, and I already had the shutdown symbol ready to go from work on the Pi button module (several posts down).  This is a two part print, some glue may help hold the inserts.  I have no idea how well it will do in the laundry though:D

You can find it here:
https://www.prusaprinters.org/prints/122790-shutdown-button

Edit - well I guess it was not as unique an idea as I had thought.  I found a couple of other entries that beat me to it :D  And one of those entries points out that this is the "Standby Button" not a power or "Shutdown" button.  Oh well, this is my stoopidstuff anyway, so I'm leaving it as the "Shutdown" button (and yes I feel horrible about that :D).