The Air Scrubber is almost done, I am just testing it before it is installed in the "enclosure".  So far it is working great though on my desk.  The blower puts out an impressive volume of air and although I had planned to control it using PWM, it seems to be running just about where I would want it when simply connected to 12V (red is +12V and black is Ground), so I think PWM is not necessary.  Running full open at 12V it only draws 750mA so it could go higher if needed - but that would require PWM control since I don't think it runs at full tilt otherwise (could be wrong but it is rated at 1.8A and it is not pulling close to that).  I filled the carbon filter box with some activated carbon pellets made from coconuts which is the way to go I think.  Some activated carbon comes from bituminous coal, so I thought it best to steer clear of that for this project.  Above the carbon box is a HEPA filter and the airflow goes from fan > carbon > HEPA.  I know this may not be the way many filters work, but I wanted the HEPA to filter any fine particles from the carbon filter before exhausting to the room. 

The black tape is 1mm neoprene gasket tape which I used to help seal between the filter body and the carbon tray, and avoid leaks, which seems to be working well.  I did not detect any leaks around the body of the filter so all the air seems to be moving through the HEPA (and I can feel the airflow though it also). 

The funnel like thing in the 1st pic is an adapter for a CPAP hose, which, when connected still has some mild suction at the end of the hose - though the hose is over a meter long and will be cut down in the final application.  I am still not sure if I will use the hose, but want to try it out as a point filter.  I should have some pics of this installed and set up soon.

I'm still working on the enclosure for my CR10S Pro, but decided to make the Air Scrubber now since I think I may be able to use it without the enclosure (for the time being).  The scrubber will use a HEPA filter for a vacuum cleaner and some granulated activated carbon made from coconut shells.  I have seen several designs for scrubbers but for some reason they place the filter before the carbon.  This filter will have the dirty air pass through some carbon granules and then through the HEPA filter before being exhausted.  I am going to try to use a CPAP hose to suck the air from around the nozzle which I suspect could help keep the particulates down, even without an enclosure.  The base is printing now (it is a 26 hour print), using a 0.6mm nozzle. 

I am building a door (two actually), for my CR10 enclosure, and so I need to have some sort of door latch.  I had started designing a latching mechanism and then thought, why not use an interior door latch from a Jeep, which is a pretty basic door latch.  When I started poking around on Amazon, I found something possibly better - a door handle from a Toyota 4Runner (and some other vehicles).  It is a bit big. but I think it will work.  I just had to model the handle (roughly) and design a mount for it.  The mount shown above is designed to help me finalize the design, but it works (roughly). The way it works is the stock door handle moves a part which connects to a block (which has a spring in it to allow it to be closed without opening the door handle).  When the door handle is opened, it moves the connector to the right, which pulls the block out of the way and allows the door to be opened.  To close the handle moves the connector to the left which pushes on the sprint loaded block and pushes it into the hole in the door sill which latches the door closed.  It is a bit thick, but I don't think it will be too ugly looking.

I bought a Lenovo M700 Tiny PC as a 2nd PC to use with some projects, but as small as it was, I needed a better solution than leaving it on my desk.  I made an under desk mount for it, with a couple dovetail rails so it can slide out when I want to work on it, or just get at the back of the PC.  I am using Mouse Without Borders with it which helps keep the desktop real estate freed up, and have managed the wires under the desk. 

I tried posting this to Thingiverse, but after adding the files, and writing up a description, the site hacked, and coughed when I hit the "publish" button, so I ended up with all my work down the toilet.  Thingiverse has been rightly taking heat from the user community lately.  It is like a slow motion train wreck, with numerous problems that seem to never get fully solved, though I like to think they are trying.  Lately though, it has become almost unusable.

Anyway, enough about Thingiverse, when (if) it comes back, and works long enough for me to post it, I will post this up and then a link here.  It will probably be called something like the title of this post.

So I had a failed print today, and since it was about 1/2 done in a 5 hour print, I decided to try and save it.  Saving a print is not easy, but not hard either when the basics are known.  I listed some steps below which I have found helpful.  These are from memory and also recent experience, so use this method at your own risk, and keep in mind that every situation is different.  Please don't copy and paste the examples below since they will NOT WORK, the gcode shown are just examples of print I was trying to save today.  

The pic at the left is from an older failed print I was able to salvage after a filament jam.  IRRC the failure was right below the chin on the model which was a good place since it was hidden, but even so I cannot see it from looking at where it failed unless I look really close.

Unfortunately I did not get pics of this failed print today when it happened, but I found that there was a bit over a meter of crushed filament that spewed forth from the side of the extruder and the printer had "finished" printing.  I cleaned up the mess and did not find anything awry with the extruder so it is still a mystery what happened.  The pics below show how the print turned out (the silver color print is the one that failed today).  The first pic shows where the failure occurred very well, but when looking at the part from the face side it is much harder to tell (2nd pic).  Physically the part is very strong and I plan to still use it.

How I save a failed print:

1. Find the layer it failed at, this can be done by measuring with a caliper.  I check in several places and then make a guess or take the average.  

2. I then need to know what the following values are, they can be found in the slicer or the gcode (Cura gcode shows them at the bottom), or take an educated guess.

Layer Height
Initial Layer Height

For this example, lets say those are:

Layer Height         0.2mm
Initial Layer Height    0.24mm

(Since the Initial layer height is just a small amount larger I will round it down, and use 0.2 there as well.)

3. Next I needed to determine what layer number the print failed at.  The layer numbers in Cura start at zero, so keep that in mind.  On my print, I averaged several measurements to be at 7.4mm where the print failed.

7.4mm / 0.2mm = 37 (in this case I rounded down the initial layer height to 0.2mm)

So my print failed at the 37th layer which, since they begin numbering at zero in Cura Gcode, will be known as "LAYER:36" in the Gcode.

4. I opened the gcode in a text editor (Notepad++ is good), and searched for "LAYER:36", I found this in my example:

;LAYER:36
M117 INDICATOR-Layer36
;TYPE:WALL-INNER
;MESH:Object 1
G1 F300 Z7.4
G1 F2700 E3259.6837
G1 F2100 X175.868 Y149.679 E3259.69867
G1 X176.236 Y149.631 E3259.71364
G1 X176.596 Y149.55 E3259.72852
G1 X176.948 Y149.441 E3259.74338
G1 X177.293 Y149.299 E3259.75843
G1 X177.624 Y149.126 E3259.77349
(etc)

I needed to grab some info from this layer 36 data.  

A. I need to know what the last value was for the extruded length.  This is necessary since it is like an odometer on a car, and needs to be reset to the last value or else the printer will (in this example) go from zero to 3259.6837mm, which would not be good.  Here the value needed is (you guessed it) from this line:

G1 F2700 E3259.6837

I am not changing that line, but have to note the value is "E3259.6837".

B. I need to know where the X and Y are going to be at the start of layer 36.  This is not really necessary, but I like to place the nozzle at the start X and Y position, and raised up by an inch or two above the top of the print on the z axis.  This way, when it starts printing again, the nozzle will go straight down and begin printing.  I took the start X and Y position from this line:

G1 F2100 X175.868 Y149.679 E3259.69867

Here I needed to note the X and Y positions which are "X175.868 Y149.679"


5.  Next, I took a look at the Gcode and commented out most of the start code, and left just what is needed to get the print going again.  This means removing any commands that are running a mesh (g29), homing (g28) or drawing priming lines (G1).  In my case, I commented out (placed a ";" in front of the lines, but they can also just be deleted).  I commented out everything in the start gcode but the following:


M140 S60             ; set bed temp to 60 degrees C, and continue
M105                 ; report temps on the terminal
M190 S60              ; set bed temp to 60 degrees C, and wait for it to stabilize before proceeding
M104 S217            ; set hotend temp to 217 degrees C, and wait for it to stabilize before proceeding
M105                ; report temps on the terminal
M109 S217             ; set hotend temp to 217 degrees C, and wait for it to stabilize before proceeding

M82 ;absolute extrusion mode
M201 X500.00 Y500.00 Z100.00 E5000.00 ;Setup machine max acceleration
M203 X500.00 Y500.00 Z10.00 E50.00 ;Setup machine max feedrate
M204 P500.00 R1000.00 T500.00 ;Setup Print/Retract/Travel acceleration
M205 X8.00 Y8.00 Z0.40 E5.00 ;Setup Jerk
M220 S100 ;Reset Feedrate
M221 S100 ;Reset Flowrate
M420 S1 Z2 ;Enable ABL using saved Mesh and Fade Height
G92 E0 ;Reset Extruder to 0 mm extruded - I will next add the correct value

; I added the following to get the nozzle to a safe spot prior to starting on layer 36:

G1 Z12.0 F3000             ;Move Z Axis up to 12mm
G1 X175.868 Y149.679 F3000.0     ;Move to start position which was grabbed from the first G1 line of layer 36, in step 4 B

; Below, I set up the extruder, so the software knows where it started

G92 E0                 ; zero the extruder again
G1 F2700 E-3.0             ;Retract a little to avoid a blob as the nozzle is hot at this point
G92 E3259.6837             ;Reset Extruder to the last value from step 4 A

6. So after the start Gcode is configured, I then just removed everything in the Gcode between ";LAYER:0" and the start of "LAYER:36" since I did not need any of that stuff (those layers are already printed).  Below are the first 58 lines of my gcode, I commented out many of the original values with ";".

Below you also will see some duplicate entries for "M92 E0" which just resets the extruder to zero.  There could be 100 of these "M90 E0" commands in there, as long as the last one is "G92 E3259.6837" which is needed to set the extruder to the starting position for layer 36 - sorry if this is confusing. 

It ain't pretty, it's just an example, and what I ran on the silver part in the pic above to resume printing at layer 36:

;FLAVOR:Marlin
;TIME:17494
;Filament used: 20.8972m
;Layer height: 0.2
;MINX:91.208
;MINY:91.207
;MINZ:0.2
;MAXX:208.792
;MAXY:208.793
;MAXZ:15.2
;Generated with Cura_SteamEngine 4.1.0
M140 S60
M105
M190 S60
M104 S217
M105
M109 S217
M82 ;absolute extrusion mode
M201 X500.00 Y500.00 Z100.00 E5000.00 ;Setup machine max acceleration
M203 X500.00 Y500.00 Z10.00 E50.00 ;Setup machine max feedrate
M204 P500.00 R1000.00 T500.00 ;Setup Print/Retract/Travel acceleration
M205 X8.00 Y8.00 Z0.40 E5.00 ;Setup Jerk
M220 S100 ;Reset Feedrate
M221 S100 ;Reset Flowrate

;G28 ;Home
M420 S1 Z2 ;Enable ABL using saved Mesh and Fade Height

G92 E0 ;Reset Extruder
G1 Z12.0 F3000 ;Move Z Axis up
G1 X175.868 Y149.679 F3000.0 ;Move to start position
;G1 X10.1 Y200.0 Z0.28 F1500.0 E15 ;Draw the first line
;G1 X10.4 Y200.0 Z0.28 F5000.0 ;Move to side a little
;G1 X10.4 Y20 Z0.28 F1500.0 E30 ;Draw the second line
;G92 E0 ;Reset Extruder
;G1 Z2.0 F3000 ;Move Z Axis up

;G92 E0
G92 E0
G1 F2700 E-3.0 ;Retract a little to avoid a blob
G92 E3259.6837 ;Reset Extruder to the last value of layer 35


;LAYER_COUNT:75
;FIXUP start at layer36 @7.4mm
;LAYER:36
M117 INDICATOR-Layer36
;TYPE:WALL-INNER
;MESH:Object 1
G1 F300 Z7.4
G1 F2700 E3259.6837
G1 F2100 X175.868 Y149.679 E3259.69867
G1 X176.236 Y149.631 E3259.71364
G1 X176.596 Y149.55 E3259.72852
G1 X176.948 Y149.441 E3259.74338
G1 X177.293 Y149.299 E3259.75843
G1 X177.624 Y149.126 E3259.77349
G1 X177.936 Y148.927 E3259.78841

;and on and on and on, to the end

7. Once the Gcode is settled, now the printer may need to re-learn where home is.  In some cases, when luck is on my side, and the printer is still on and did not loose any steps, it may still know where home is.  When I think it may have lost steps, lost power or I stupidly reset it, I then need to re-home the printer.  I cannot usually simply auto home the printer however, since the print is most likely in the way.  To home it in this situation, I use Octopi, but Proterface or even the printer's native interface could be used.  To do this, I followed this process:

A. Raise the z axis higher than the print so it can move in the x and y freely without hitting anything, I usually go a good inch or two above the print.

B. Home the X and Y ONLY, do not home the Z yet.

C. Homing the Z can be tricky.  My printer wants to home the Z to a position at the front left of the bed so if I had a print there, it would interfere.  If this area is clear, I would move the X and Y to the front left and then home the Z, being careful to watch that it does not interfere and ready to stop the printer.  It's also helpful to keep that in mind when placing prints on the bed in Cura.

If I cannot home the Z normally, then I can do it manually.  This requires a clear place on the bed where the nozzle can be homed and the terminal to send commands to the printer.  I am writing this from memory, but what I recall is that I had to lower the nozzle to the bed and set the offset using the paper or feeler gauge method.  Then I would send "G92 Z0.2", this would take into account the paper thickness of 0.2mm and the G92 command sets the position.  There is no need to tell it what the X, Y or extruder positions are since the X and Y were homed already and the extruder will be reset when the gcode is run.  

D. Regardless of how the Z is homed, before moving on, I would raise the Z to a safe height where it will not interfere with the print, I usually go a couple inches higher than the top of the failed print.

8. So now I have the gcode set up to start at layer 36, the gcode will reset the extruder to the correct starting value, and most importantly, the gcode will not try and home or autolevel before the print as that will hit the print we want to salvage (and maybe break parts of the printer).  I have also homed the X, Y and Z, so the printer has it bearings in the world.  If that is all a go, then I would load the gcode and start it, but keeping a very close eye on the first layer to be sure I didn't screw anything up.  This is very important and if it looks like it is too high or low, I would just stop the print since that can be fixed the same way as this process.  


Last thoughts - It is hard to nail the exact layer though measuring since I sometimes find that measurements taken in different spots don't agree 100%, so I average.  If I guessed high or low by a layer it will usually be OK, but if it will not stick, or looks like it is tearing things up, I would stop it, clean up the print as best I can, and repeat the process but adjusting the start layer by plus / minus 1 or 2 layers or whatever it seems to need.  If the printer did not lose steps of lose the home position then I can sometimes get by without re-homing and just fix the gcode and start again.

Another thought which I did not mention above, is that it may help to get more accurate results when homing the Z to pre-heat the bed.  That will also help insure that the print does not pop off during the process of homing or measuring, which they can do more easily on a cold build surface.  If the print pops off it is pretty much game over since there will be no way to get it back in the same position with any accuracy.

I have saved prints where it is almost impossible to see where the print failed, and some where it is easy due to a missing layer or half layer.  It is more an art than a science, but the above steps should get things into the ballpark.

I just picked up a Lenovo M700 Tiny Desktop with an i5 processor pretty cheap and 2nd (3rd?) hand.  It had no power supply or OS, but the cool thing is, systems that shipped with windows 10 don't need a CD key since the activation is done without it now.  I was able to get a power supply for about $15 and put in a spare SSD I had from a prior upgrade.  Now I have a system to test with, and the form factor is small enough that I can probably design an under desk mount or something for it. 

Since I want to keep things simple, I don't want another keyboard and mouse cluttering my desk, which is where software like Synergy or Mouse Without Borders comes in.  These tools allow one mouse and keyboard to be used across several network connected machines.  Since I'm cheap, and Synergy costs money, I went with (the free) Mouse Without Borders, which is a Microsoft "Garage" project and available here.  It needs to be installed on both machines and I set it up on the primary machine with the keyboard and mouse first.  The setup process requires adding the machine name and a key which you get from the first machine to be set up.  I had a problem however, which was due to the primary machine not having network discovery turned on.  Once I enabled network discovery, everything worked fine and I can move my mouse across monitors to the new M700 PC and back, and use one keyboard with both.  It makes sense that network discovery would be needed since it is a Microsoft product, though some option for a direct TCP/IP connection would be handy.  Mouse Without Borders also allows files to be dragged and dropped across PC's which is pretty cool.  Since I have both PC's connected to the same switch, there is no noticeable lag either - but I would not try to game using Mouse Without Borders.

While figuring this out, I also read that some people suggested manually adding the host and IP instead of letting the program automatically set them up.  I tried that during setup and it did not help with the connection problem (network discovery fixed that) - BUT adding the hosts manually does seem to help with reconnecting after one machine is restarted.

To add the PC's manually, go to settings.  If you are installing and having problems, you can skip the setup and the settings will then open.  In settings, go to the "IP Mappings" tab and enter the hostname of the other machine or machines that you want to share the keyboard/mouse with, and their IP address.  There are examples already there which will be removed when type in the box, the format is:

HOSTNAME IP_ADDRESS

which would look like this:

MYPC 192.168.1.22

You can get the hostname by going to the search box, and typing "cmd" which will show the "Command Prompt" app, click that which will open a window with a cursor.  Click in the Command Prompt window and then enter "ipconfig /all" which will spew out a bunch of information about your IP address, and other things, but what you need is the Hos Name and IPv4 Address, which may say "(preferred)" next to it.  The Command Prompt window can be closed by typing "exit" or just closing it like any other window.  You can use the Host Name and IPv4 address to set up the manual "IP Mappings" in Mouse Without Borders like the example above - by entering the info for the remote PC you want to share with.  I did this on both sides and it helped with reconnecting.

Mouse Without Borders works when the logon screen is active as well - which would be a problem otherwise.

Update - There was one thing that was bugging me about the way MWB works.  Without a physical mouse connected, it did not show the cursor for resizing a window when hovering over a edge or corner.  This was fixed by plugging in a mouse to the PC (I just plugged one into the back of the PC).  I may try a wireless usb mouse to see if that will make it work.

After all the luck I've had with the Ender3, I thought I'd double down and buy a used CR10S pro.  I was looking at several printers including the Artellery Sidewinder X1, the Anycubic Chiron and the CR10S Pro.  Although all those printers have their pluses and minuses, the largest community is going to be for the CR10 variants.  That mean a lot when you can expect to have problems.  Sealing the deal was a used CR10S Pro I found and the fact that my Ender and Delta are now offline for a while due to the heat where they are stationed (garage).  I can't get reliable prints from either of them right now and it make sense the heat is the problem.

I don't like having printers in the house because of the air pollution they can cause, as well as the noise.  Since I would need to bring a printer inside to use it in the heat of the summer, I am making an enclosure.  Since I have not received the printer yet, I cannot be sure if it will fit so if it doesn't, the Ender3 will get a new home.  If it does fit, it will be tight, though I have some ideas on how to make sure it does fit.  The biggest problem is the cost - this comes in at about $325 including shipping but not including tax.  I also need test print some of the parts to verify they will fit the way I want them to (so this project has a ways to go). 

This has not been posted and may not be since there are a ton of better Titan Aero mounts for the CR10 / Ender3.  My mount however has had one major issue which was the fan duct.  The original duct was too close to the hot end, and over time the airflow became disturbed as the duct warped a bit.  Also it was not low enough.  I redesigned it to hopefully fix both issues and feel that this new duct should be pretty robust and offer a much less restricted airflow than the old one.

The old version of the duct is below, and regardless of how well the new one works, I won't be going back to the old design.

I bought some TPU to try out, but I read that the stuff needs to be kept dry, more so than PLA.  I just keep PLA in bags and am not really good about monitoring humidity (but I have found that it seems to recover pretty well in a dehydrator).  I checked around for filament boxes, and it looks like people use the rubbermaid cereal storage containers for single rolls, which should be air tight.  One of those, and some silica gel beads should work out OK, but I want to keep the filament in the box while it is being used.  That means I need to have a way to get the filament out of the box.  I saw something like the design above on thingiverse, but I could not find it when I went back to locate it.  Once I find it, I will add the link (UPDATE - here it is) , but for now, this is what my version of a filament pass through is looking like.  It will have a screw on cap for storing the filament, and there will be an o-ring inside the cap, along with a place for another one on the back plate.  I expect that I will need to use silicone around the screw holes and on the front plate, but the combination of o-rings and sealer will hopefully keep the box air tight when stored with the cap.

Update 7/21/2019:  The filament pass through is posted here.

Update 7/20/2019 - The design for the filament box is almost completed and I am pretty sure that the remaining changes will not affect the way it fits or works much.  The major changes from the initial design was to drop the part that that goes through the center of a spool and just have it roll.  To help wrangle the smaller spools, there is now a small vertical roller which slides in a dovetail track.  The final design adds a rubber band to keep some tension on the vertical roller.  You can find the final design (not fully tested yet) here.

I was having a problem with a surface which I was trying to run Active Backup for Business to do a bare metal backup of the C drive to a Synology NAS box.  It kept failing with an error code 8004230f.  Researching that error, I found some info that it could be a conflict with other backup software, but there was no other backup software installed on the box (ever). 

The event viewer showed some errors for VSS (Volume Shadow Copy) which were found under the Event Viewer > Windows Logs > Application and had a source of "VSS".  The errors were 22 and 12292.  Looking those errors up, I found this which solved the problem - that is, I backed up the registry and then removed the VSS provider key for Hyper-V, rebooted and kicked off a backup (from the Synology) which is now running without errors.