3D Printers

[Spectere]

Had a bunch of underextrusion issues recently, then a bunch of misdiagnoses. Basically, the old extruder gear was set up in such a way that the spools of Hatchbox PLA that I have would pose no threat to it. The Flexion, however, would skip. I'm thinking that's because the MK10 extruder has a bunch of long teeth while the Flexion has a bunch of sharp, short teeth designed for gripping flexible filament. That pretty much all comes down to the Wanhao-style spool holder; it's barely long enough to hold 1kg Hatchbox spools, so the spools rub against the metal arm on the spool holder.

I'd initially misdiagnosed this as the extruder needing to be recalibrated, so I spun my wheels with that for a while before I remembered that PETG printed perfectly. The spool of PETG that I have is eSUN branded, and they use narrower 1kg spools than Hatchbox does. I set everything back to normal, did some of the calibration tests again, and found that if I manually unwound the Hatchbox the results came out perfectly. If I let the extruder unwind the filament, the gear would slip and I'd get wicked underextrusion. Grr. As least that only resulted in one wasted night.

So I ended up printing an extended spool holder and installing it. I didn't have time to really test it, but I did throw a kilo spool of Hatchbox on it and it spun much more freely. I don't have any picture of it handy (I installed it at like 3AM, forgot to bring my phone downstairs with me, and was too lazy to run back up and get it). I'll try to remember to snap a pic when I get home today.

Edit: Spool holder!



Also, my first Maker Box arrived today. It's got some really pretty Proto-pasta metallic blue HTPLA inside:



It also had...Landfillament:



There were a couple more things but LANDFILLAMENT.

[Spectere]

Got a few more mods incoming! I think I'm as addicted to modding that thing as I am to the sweet smell of melted PLA.

First off, the build surface on my printer is basically fucked. On my OctoPrint camera rig, the edges of the Chinese BuildTak knockoff print surface still have that matte appearance, but the center looks very smooth. In person it looks even worse, thanks to my noobish scraper stabbing (mistake #1, don't use a 60C hotbed setting for PLA, seeing as its glass transition temperature is 60-65C; mistake #2, if the print has a chance to cool all night, don't jab it with a scraper--heat the bed up to temperature, then let it cool to help release the print).

Basically, the bed was starting to become nearly impossible to properly level, giving me highly inconsistent first layers (some parts would be very smooth, other sections would have obvious printer lines) and poor adhesion for smaller models, among other things. I tried to fiddle with it the other day but I literally couldn't even get a calibration cube to print. That's pretty sad. I could have printed it offset, but that's not exactly fixing the underlying problem.

Wanhao/Monoprice helpfully provide a second build surface, but I'm not going to go that route. That material is very much temporary. Even without my questionable techniques it probably wouldn't have lasted that much longer than it did. Instead, I opted to upgrade to a glass bed with a PEI sheet. It's going to involve a bit of relearning (and ripping off a lot of adhesive from the metal hotbed) but from what I've seen and heard it'll be well worth the effort. That'll give it a nice, rigid surface to print on, and using PEI will ensure that the bottom of the print is extremely smooth. I didn't really want to screw around with hairspray or glue sticks and blue painter's tape adds a distinct texture to the base of the model.

That's the most functional upgrade I'm doing this time around, but it should be a pretty big one. In addition to that, I'm also going to be replacing the linear bearings for the bed to make y-axis movements smoother and quieter, as well as replacing the belt tensioners. The ones that are included are spring-loaded so they have a bit of slack. I'm going to print new ones out of PLA, which should prove to be a bit more rigid.

In other news, Proto-Pasta Translucent Silver Smoke HTPLA looks gorgeous:

[Bobbias]

Nice choice of background for that picture.

[Spectere]

Thanks! My SNES/PVM setup is right near the printer. It definitely comes in handy when I'm calibrating or doing a lot of small prints.

Also, mods were installed. I'm really amazed at how much of a difference the linear bearings and glass/PEI made! The linear bearings drastically reduced the noise of y-axis movements (not sure if the bearings or white lithium grease made a bigger difference--either way, it was effective). The glass/PEI surface makes the base of the prints unbelievably smooth and, as an added bonus, makes them much easier to detach. Before I'd have to pretty much pry prints from the bed, especially if the heated bed cooled to room temperature, but earlier today I was able to just pull the print off. As for the skirt, a quick jab with my fingernail caused it to release. Holy crap.

One issue is that I'm using binder clips to hold the surface on now. It does a good job holding it, but considering how large my cooler is now it's noticeably decreasing the amount of space I have. There are a couple of options: I could either attach the PEI directly to the glass. The glass has thermal pads that are holding it pretty firmly in place, so I could get rid of the clips altogether. Alternatively, I could experiment with other methods of adhesion and print directly on the glass.

[Bobbias]

Note to self: if I ever get a 3D printer, get something that doesn't end up causing me to make a million mods

[Spectere]

Ooh, good luck with that.

Honestly, it all depends on what you're willing to spend on the base printer.  My printer was about US$300. I put maybe $350 worth of mods into it (the most expensive one being the extruder at $180), but with the combination of mods that I selected it gives it the level of performance as a $1500 printer (Edit: lol no). It did take a bit of work to get it there, but I enjoy doing that sort of thing.

Additionally, this is a good printer to get started with. Aside from one mod that I'd consider important for safety (bypassing a screw terminal that isn't rated for the current passing through it--a MOSFET board, a few cents worth of wire, a printed raft for it to sit on, and some industrial velcro to hold it on--roughly $15 total cost), none of the other mods are essential for getting great prints. Even right out of the box that printer is kind of a beast for the price. The commonly recommended mods for it really just take it from making great prints to making even better prints. It's a great base unit for getting into the craft.

If you want one that's truly going to give you an amazing out of box experience, you'd want to get something like an Ultimaker. It's very expensive ($2500 for the UM2+ and $3500 for the UM3) but with that price you're buying a stellar machine and excellent support. Another option is the Prusa i3 MK2S ($699 for a DIY kit, $899 pre-assembled). Basically, it's an evolution of my printer's design, and includes a lot of great features (auto-leveling bed, included all-metal E3D V6 hotend, PEI surface, 50 micron layer height, etc). IMO it's a bit of an expensive beast for just breaking into the hobby, but it's a nice piece of kit for the cost.

I have to admit, I'm really considering moving up to the Prusa just because of this upcoming kit. 4 material prints? Sign me the fuck up.

Alternatively, I could always just build my own multi-material printer. That might be fun.

[Bobbias]

Yeah, currently having enough trouble saving up for my PC, so any 3D printer I buy will be a long way off, if I ever decide I want one bad enough.

But seriously, a screw terminal not rated for the current? Jesus...

[Spectere]

It's a fun "quirk" with the Melzi boards, and the screw terminal that they use now isn't nearly as bad as the connectors that they used to use. I'm not aware of recent v2.1 Di3s catching on fire (seems like it's mostly the old v2.1s and earlier) but I don't really want to risk it. I've been thinking about getting a MOSFET board for the hotend as well, though that doesn't draw nearly as much current as the hotbed does.

And hey, it's still a downright safe system compared to other i3 clones, like the Anet A8. Anet actually disabled the thermal runaway protection on the standard firmware. Who knows what else they skimped on.

Edit: Also, I should add that "Melzi," being Italian, is pronounced "MELT-zi." Hah.

[Spectere]

I got a new printer! Here's some pics (warning: might be NSFW):

aaahHhHhhhhhhhhHHhhHhHHhhh pic.twitter.com/jE9rkDqDFE

— Ian Burgmyer (@Spectere) January 29, 2018

And a video to show how quiet this damn thing is:

IT’S SO QUIET pic.twitter.com/FS2L9Q5WFB

— Ian Burgmyer (@Spectere) January 29, 2018

[Spectere]

I think I'm just going to keep this thread a bit active just to ramble about this stuff. Here we go!

So I've been playing around with flexible PLA. It prints super stringy (I thought PETG was bad...this is much worse) and it takes a bit of tweaking to get any actual flex out of it.

As for what I'm printing now...



Hmm, what could these be?

Edit: Oh yeah, I also published my first object on Thingiverse the other day: https://www.thingiverse.com/thing:2852942. It's a mount for the Raspberry Pi Compute Module I/O board. Looks like five people already put it on their to-do list.

Here's a pic with the board mounted:

[Spectere]

'tis finished!

Ladies and gentlemen, meet my new best friend. pic.twitter.com/6jaixLgGpk

— Ian Burgmyer (@Spectere) April 11, 2018

[Spectere]

So I bought a new 3D printer today, because why the hell not.

So...I have a LulzBot TAZ 6 now. pic.twitter.com/9i8Fd3oTiD

— Ian Burgmyer (@Spectere) April 28, 2018

And to give y'all an idea how big it is, here it is next to the Prusa:

This thing is freaking huge. XD pic.twitter.com/CYoYOZet9p

— Ian Burgmyer (@Spectere) April 28, 2018

[Bobbias]

That is substantially larger lol

[Spectere]

YEP. It took a bit of shuffling to get everything to fit comfortably. The build volume is a fair amount larger than my Prusa i3 MK3. The Prusa is 250x210x210 while the LulzBot is 280x280x250, so I'm looking forward to taking advantage of that.

I'm only on my third print on the LulzBot (as opposed to the 20+ days of printing time I've clocked up on the Prusa), but here's some observations so far:

- The Prusa is much quieter. Than again, that's kind of a selling point for the MK3. I don't think it's a stretch to say that it's the quietest FDM printer on the market.

- The LulzBot has a borosilicate glass plate with a PEI sheet affixed, held on with washers (which double as probing points for the bed leveling system). The Prusa uses a spring steel sheet with a PEI sheet affixed, held on with rare earth magnets. Obviously the Prusa wins here. I've never had to take a scraper to the build surface, but I've had to scrape both prints off the LulzBot's bed. Talk about nerve-wracking. I have a feeling that's more due to the sample material being colorFabb nGen, which is a copolyester. Copolyesters tend to cling to PEI sheets. I put down some glue stick to act as a separation layer, but it really didn't seem to help much, heh. I'm printing with PLA right now, so hopefully that'll release more easily.

- The Prusa uses 1.75mm filament while the LulzBot uses 2.85mm, so I can't use my old stock. I did get a spool of 2.85mm Polyalchemy Elixir, but I can't really use my old stock. Well, I kinda can. The extruder on the LulzBot can apparently feed some 1.75mm PLA since the material is so stiff, but I don't really want to risk it. However, the tool head on the LulzBot is nothing short of phenomenal. To replace the tool head on most printers you have to literally disassemble it. On the LulzBot, you remove a screw and unplug a wiring harness, then swap it with a new one. I could build a tool head that can accept 1.75mm filament with relative ease, and I believe there's a vendor that sells them pre-assembled. Being able to swap between 1.75mm and 2.85mm in about the time it would take to swap filament is freaking amazing.

- Aleph Objects, the creators of the LulzBot, are based on the US, while Prusa Research is based on the Czech Republic. I'm not saying that to be Das Überpatriot, but it does make getting replacement parts (should I need them) much faster.

- Both printers are fully open source, run the same basic firmware (Marlin), contribute heavily to open source projects, and ACTUALLY HAVE THE GODDAMN SAFETY FEATURES ENABLED IN THEIR FIRMWARE SO THAT THEY DON'T BURN PEOPLES' HOUSES DOWN.

- Seems like it can print at about the same speed as the Prusa, though from what I understand it handles 50 micron layer heights quite a bit better.

- The part cooling system is significantly better on the LulzBot. The Prusa has a decent part cooler, but the TAZ 6 just throws subtlety out the window and has two fans on either side of the print. I'm going to need to do some bridging to test this.

- Build quality is stellar. The frame feels solid and the linear rods are about 50% thicker than what most printers use (it looks like they're 12mm, while most use 8mm). I think even Ultimaker uses 8mm rods.

- I haven't done enough printing to have fully tested this, but on my initial prints there seems to be less obvious ghosting than what I get on the MK3. I'm thinking the more rigid frame has a lot to do with this, not to mention the filament spool being low on the side rather than wobbling around above the gantry.

- The power switch on the LulzBot is something to behold. It sort of has a similar feeling to the old IBM AT power supplies. It's either firmly on or firmly off, with no chance for any in-betweens.

- The display is laggier than the one on the Prusa but more responsive than the one on my old Wanhao i3. Not a huge deal.

- As with the Prusa, the installation manuals and user guide are super useful.

- Most importantly: Aleph Objects are fucking memelords. Their assembly guide is called OHAI ("Open Hardware Assembly Instructions" but YOU KNOW WHAT YOU DID). One of their upgraded extruder tool heads is called the MOARStruder. I mean, they call their printers LulzBots FFS.

Yeahhhhh, I love it.

[Bobbias]

Fucking memelords indeed lol. And yeah the stiffer frame probably contributes quite a bit there.