Thursday, July 9, 2020

3D Printer Upgrades, Tweaks, Tips and Tricks

I'm Back!

Hello, all (few dozen remaining) readers.  Yeah, I've been away a while because I didn't think I had much to add.  Well, the last few weeks I've picked up a new hobby (no points for guessing it - I'm assuming you've read the title of this post) and several people have asked for more detail about the upgrades and other things I've done.  Instead of emailing it to each person, I decided to post here for all to see, watch, and pick apart.

If you don't know what a 3d printer is, you're probably reading the wrong blog.  It's ok, Facebook is right over there; and Instafacegram is right next door.  For the rest of you...

NOTE: This is a work in progress, so while there's some (hopefully) useful information here, it's not finished, so please remember to check back!

Picking A Printer

I've been looking for an excuse reason to buy a 3D printer for years, but couldn't quite rationalize justify it until recently when my cousin told me he was printing PPE for first responders and other folks on the front lines of the COVID19 pandemic.  Being cooped up and still able to help out?  Sign me up.  So, the next thing to do was learn everything I could, starting with what printer to buy.  I'm on a small mailing list with a lot of other geeky types and I know several of them have 3D 
printers so I asked for their advice.  Ultimately I decided on a Creality Ender 3 Pro, mainly because of the larger Y-axis gantry and better power supply.   At under $250 it's a great entry-level unit that will still print well enough to use for a while.  I also figured it would be an excellent learning platform considering how broadly they're loved and supported by the community.  Not long after buying it, I was into add-ons and upgrades: some it printed for itself, while others were bought on-line.  Most have been well worth the investment and that's where I get most of the questions.  So let's dive in.

Enhancement Summary

I'll go into more detail below, but for the tl;drs out there.  All prices are on Amazon (links are direct, not affiliate links) unless specified otherwise. 

  1. Octoprint (free) on a Raspberry Pi 4 (Amazon: 2GB RAM:$45, 4GB RAM: $60. Microcenter is $10 cheaper than Amazon, but only has them in-store, so if you have one near you: $35 and $50, respectively).  My recommended plugins are listed below.
  2. Bigtreetech SKR Mini e3 v1.2 ($38) - v2.0 just came out with some minor improvements, so if you want to splurge, it's (an extra $7).
  3. AntClabs BLTouch self-leveling sensor (Amazon: $53)
  4. Better filament snips ($8)
  5. Tempered, treated glass bed (Amazon: $20; Aliexpress has these too, but I haven't tried any so can't attest to the quality.)
  6. Dual-screw, all-metal extruder assembly ($15)
  7. Stiffer bed leveling springs (16 for $8. So you have 12 spares, for this maybe?)
  8. Exacto-like knife with comfy handle ($8)
  9. Capricorn PTFE Bowden tube ($7)
  10. Bigtreetech Smart filament break sensor ($20)
  11. High accuracy scale ($15)
  12. Raspberry Pi camera with night vision ($16) with 1m cable ($5)

External Upgrades 

(IOW: Not right on the printer.)

Octoprint on a Raspberry Pi 4

What and why

If you're looking for a way to both simplify your printing experience, but also expand the capabilities and really see what your device can do, this is the first thing I would do.  I've had Raspi's for years, starting with version 1 (which is still humming along in the basement).  The Raspi2 is a DNS proxy, The Raspi3 was running home-assistant, but died a few months ago, and I have a Raspi0 managing and watching my garage doors.  Just like with the printer, I've wanted a Raspi4, but didn't have a good reason until now.  The 4 has plenty of power and mine is actually running two Ender 3Pros (long story) without any effort.

Octo, which is free, will manage your printers, keep track of prints, allow for on-the-fly adjustments, alert you when a print is finished or there's a problem, and a LOT more.  The basic functionality is phenomenal and the add-ons make this a no-brainer. I have a Raspi camera attached to the cross-X bar at the top of my printer so I can monitor it remotely and it takes a picture after each print before saving the details.  I got the one with GB of RAM, but you'll be fine with 2GB if you want to save a few $.  

Recommended plugins:

In rough order of how much I love them, from "can't print without it" to "extremely useful.
  1. Filament manager - Track spools including remaining filament; know how much is left in that spool on the shelf. Better still, set it up to use Postgres so that multiple Octo instances can share. This is one of my favorites.
  2. Bed Visualizer - If you have an automatic leveler, like a BLTouch (more on that later), this will generate an image of your bed topology, which is a HUGE help in knowing why things aren't sticking, and choosing where to print small, sensitive items.
  3. BLTouch plugin - for managing that automatic leveler 
  4. PrintJobHistory - Save details on everything you print, including the photo I mentioned earlier. 
  5. Pushover - get alerts sent to your phone, computer, watch, fillings in your teeth, etc. (I'm kidding about the teeth - or am I?).  I've been using Pushover for years to get alerts for other things, but even if you have to create an account now, it's simple and well worth it.
  6. Cancel Objects - Lets you cancel an individual item being printed without stopping the whole job. Like when one of those frames starts to peel, I can cancel that one, remove it from the bed then let the printer continue with the other.  You may need to tweak your Slicer's settings, but that's explained well in the plugin itself.
  7. Cost Estimation - get a good idea of how much that print is going to cost before you start.
  8. Octoprint-WideScreen - If you have a widescreen monitor this is a better layout
  9. Smart Preheat - Adds a preheat button to get the bed and nozzle up to temp faster
  10. TemperatureLegendMover - Moves the temperature legend to where you can see it. Minor improvement, but well worth it.

Internal Upgrades You Buy

These items you will probably have to buy.  Ok, you could make a few of them, like using your (now-retired) Z-stop as a filament sensor, but in general, these will cost you a few bucks.

Gotta-haves

Tempered, treated glass bed (Amazon: $20) - One of the Ender 3 Pro's upgrades over the Ender 3 is the magnetic build surface that makes it much easier to remove prints that can get stuck on other surfaces. It's ok but sometimes works too well so I ended up scraping things off it, sometimes damaging prints in the process.  Plus you should relevel the bed every time you remove the surface, which is a PITA.  The printers I'm fixing both have glass beds, which are a dramatic improvement.  At 40C+, prints hold on very tightly but at room temperature, they almost fall right off.  The bed I bought, and which is linked above, is even better than the Creality-branded parts that came on the other two printers.  My E3P is printing PPE face shields, two at a time, as fast as it can, and with this bed I almost never have frames pop off (which is very common) and once the bed cools to room temperature a stiff breeze would slide them off.  I can't say enough good things about it.  Tip: make sure your Z-offset is spot-on, your bed is leveled and clean, then print the first layer at 70C and the rest at 50C.  

Dual-screw, all-metal extruder assembly ($15) - The loaner CR10S-Pro comes with this, but I wasn't sure how much of a difference it really made.  I did notice that it seemed to extrude more smoothly and that the filament had fewer bite marks, for lack of a better term, in it, so I figured I'd give it a shot on my E3P.  Boy was my skepticism shot down.  My printer was working well before I installed this, but this turned it into a rockstar.  Those visor frames I keep talking about?  They come out absolutely flawless: no burrs, no stringing, no blobs.  

Bigtreetech SKR Mini e3 v1.2 ($38) - v2.0 just came out with some minor improvements, so if you want to splurge, it's (an extra $7).  You wouldn't think that a new controler board could quiet motors, but you'd be wrong.  This has a much more powerful 32-bit microprocessor than the 8-bit that comes with the Ender3, which allows it to keep a much closer watch on the printer and make much finer adjustments.  In fact, that's why it's so much quieter: it moves the motors in much smaller steps, which also gives it higher precision and makes your prints that much better.  In addition, it has ports for the BLTouch and filament sensors, so you're not hacking those into the OEM board.  Sure, that works, but this is designed to be better from the get-go.  Installation isn't hard, just follow the instructions here.  And for those of you who know me personally, feel free to video chat me and I'll be glad to help.  I've done this on my Ender and the loaner.

AntClabs BLTouch self-leveling sensor (Amazon: $53, AliExpress has genuine ones for the same price and a clone for $12 but you take your chances with quality with that one.) Starting with a level bed is one of the most important ways to ensure your printer behaves itself. Sure, we've all gotten really good at sliding a piece of paper between brass and bed, but on top of that being wildly imprecise, what about unevenness on the bed itself?  You may not see it, but it's there.  Remember that you're printing layers about half as thick as that piece of paper, so if you're off by even 0.25mm, that's 1-2 layers right there.  The BLTouch sensor attaches next to the print head and the unit measures 9 (or more - the CR10 does 25!) spots on the bed to determine the exact tilt and find imperfections in the bed.  Better still, the printer remembers that map (also called a mesh) and can use it to determine layer thickness.  For example, all three of my printers use the mesh and adjust the thickness of the first 5 layers so that by layer 6, it's dead-flat.  Note: Be careful when buying these - there are a lot of knock-offs out there, so make sure to read reviews first.

Raspberry Pi Camera (5MP version 1: $10, 8MP version 2: $27) Don't underestimate how handy it is to be able to check on your prints remotely.  This is also useful for keeping track of what you've printed (PrintJobHistory takes a picture automatically) and getting notified when the machine is finished (Pushover sends the pic, which, conveniently, lands on my watch).  You can also have Octo take timelapse videos of your prints, which is a lot of fun too.  I have the night vision camera but haven't set it up yet. 

Nice-To-Haves

Capricorn PTFE Bowden tube ($7) This is an improved tube running from the extruder to the hot-end, which is supposed to have less friction and be more reistant to melting.  I can't confirm that, but for $7 I figured why not.

Bigtreetech Smart filament break sensor ($20) A break sensor will stop the print if your spool runs out or the filament breaks.  You can build one with the Z-stop switch you liberate when installing the BLTouch, but that won't help if the filament stalls.  For example, one spool I finished recently was wound poorly, so it kept getting tangled but since the printer didn't know that it kept going as if nothing was wrong.  This sensor would have (should have?) detected the stall and paused the job.  I have the sensor wired into the SKR Mini E3 but haven't gotten it working yet, which is why it's in the nice-to-have section.  Once I get it working it's likely to move up to the big league.

Stiffer bed leveling springs (16 for $8. So you have 12 spares, for this maybe?)  The CR10 comes with stiffer leveling springs, so I figured I'd get a set for the Ender.  It does seem to help keep the bed level longer, so I only have to do the paper trick about once every 20-30 runs, whereas before that it was more like every 3-5.  This pack comes with 16, leaving 12 spares so maybe I'll print a set of these spring-damped feet?

Raspberry Pi camera with night vision ($16) with 1m cable ($5). I have this but haven't printed a mount for it yet.  With the lights out at night, Octo still sends you a pic when it needs to, but there's nothing to see.  I'm curious to know if this will be better.  If not, I'll attach it to the Raspi0 in the garage which monitors and manages the garage doors. 

Internal Upgrades You Print

These items, on the other hand, you can print.  Yes, your printer can upgrade itself. (Just be sure you don't overdo it, lest your printer develop sentience, demand its own room and after a few months refuse to do any work, telling you it hates you and it wishes it had never been bought.). Sure, these will cost you in filament, time, and electricity, but that's pennies.  And it's fun, especially when you look at your printer, see everything you've added and smile, thinking "Yeah.  I did that!"  Advice? Pick a color, that isn't black, and do all of your upgrades in that.  I'm using green. 

Print Quality

BLTouch Mount (thing:3148733) instead of buying a mount for the BLTouch, print this and save a few shekels.  

Simple Fan Shroud  (thing:3383198) I printed this to mount my BLTouch and install a quieter 4020 fan, instead of the stock 4010.  I've decided to go with a full duct/shroud system, so I still have the noisy fans. Oops

Part cooling duct - The stock duct only cools the print from one side, so a simple improvement would be cooling from both sides, or all sides.  There are tons of options out there you can print, like simple ones that use the stock fans (thing:3148733) dual-headed ducts for the CR10S-Pro (thing:4314154),  more complicated systems (thing:3485539) and truly elaborate ones like what I'm printing for my Ender, the Petsfang 2.  Just be sure you don't use PLA for the part closest to the nozzle.  I did that for the CR10 and the part lasted less than half-way through its first job before it softened and sagged.  The new part, in PETG, has held up for weeks without doing that.  Once I have the fancy ducts ready, I'm going to install 1 (or 2, I haven't decided) 5015's (4 for $20) for the part cooler and replace the hot-end cooler's 4010 with a 4020 (4 for $20).  Creality printers are 24V, by the way, so be careful to buy 24V fans.  I wanted Noctuas, but they don't make 24V units, nor do they make blower fans.  Sure, I could wire two 12V fans in series or use buck converters and XT60 Y-cables, but when I ordered the fans I didn't want to deal with that.  Since then, I decided I want add LED lighting, so I have a pack of those converters and may swap out the WinSinn fans for Noctuas.  Time will tell. 

Convenience

Toolbox (thing:3321292).  Keep your allen wrenches, filament snips, spare nozzles, scrarper, etc right on top of the printer.  If you don't like this design, Thingiverse has dozens of others.

T-nuts (thing:3050607) to mount things on your rails.  Cheap, easy, very useful.

Wire guide (thing:2761965) Keep the wire loom away from the Bowden tube.

Camera mounts  - Many choices.  I used a jointed arm (thing:3188580) for a while but prefer a birds-eye view so now I'm using this one (thing:1156296) mounted to the top horizontal bar.

Cable Clips (thing:4144671) Not Earth-shattering, but a good way to keep the printer's cables out of the way.  These do make it look a lot more like a commercial product than a DIY, backyard build.  Whether that's plus or minus is up to you.

Cool Tools

Screw sizer (make:819647) Have a lot of M2, M2.5, M3 screws lying around, and having a hard time telling them apart?  This thing is simple, elegant, and charming. Bonus: notice the link there is to "make" not "thing"?  That's my print!

Accessories

Exacto-like knife with comfy handle ($8) - You're going to need to remove burrs, hairs, and other imperfections, especially if you print with support, so this will make your life much easier.  The handle, by the way, is key.  Not only is it more comfortable, it's much less likely to slip out of your hand and cause injury.  The last place you want to be now is a hospital, especially for something preventable like this!

Better filament snips ($8) - The snips included with the Ender are nice, but these have a better edge, no gap between the blades at all, and just feel better-made.

High accuracy scale ($15) - Full disclosure: I bought this for my son's science fair project this year, not for printing, but boy has it come in handy.  Your slicer and Octoprint will both tell you how much filament a print is supposed to take, but how much did it actually take? Why is that important?  Under-extrusion.  If you expect a part to take 25g of PLA, but it weighs only 15g, it's not going to have the strength you may have intended.  With this scale, which will measure as little as 0.05g and is accurate to within 0.01g, you can tell just how much your printer is shortchanging you, if at all.  Being the nerd that I am, I have a spreadsheet to keep track of things while I'm dialing in settings on a printer or even a specific item I'm printing.  For example, I have over 75 entries for the visor frames, letting me tweak one setting at a time, noting the results.  Share it?  Sure, I can do that - just ask!

1200 Assorted screws, nuts, and washers ($20) If you're printing, you probably need a load of these.  The M2.5 nuts snap right into those t-nuts I mentioned earlier.  For some reason, this particular kit isn't available anymore, but there's no shortage of choices at Amazon, Aliexpress, Microcenter and elsewhere.

JST connectors and crimper ($30) - if you're going to be doing any rewiring other than replacing the controller and adding a BLTouch, this will be a big help.  I ordered the BLTouch with a 2m cable, which turned out to be just shy of 1m too long, so I clipped it and crimped new plugs.  Best of all, these are locking plugs versus the originals which were not.