Our 3D Printers operate on many of the same principles, but have some important distinctions between them which will affect how you get the machine ready to print your part. Be sure that you’re using the same machine you sliced the file for in Cura, otherwise you will likely have a bad experience.
Lulzbot Taz 6
The Taz 6 uses 2.85mm diameter filament, and has a
larger build volume. To load filament
1. Power the machine on.
2. In the navigation menu, choose ‘Change Filament’
3. Choose either ‘Preheat PLA’ or ‘Preheat ABS’, depending on the temperature needed by the filament you are using. Getting an exact temperature match isn’t crucial here, so consult the Material Chart and pick which one more closely fits you filament.
4. The printer will home, begin heating, and unload any filament that is loaded. While it’s doing this you can get your filamnet loaded on the spool holder and ready to go.
5. When prompted, disengage the filament guide on the print head, feed your filament in until you get a bit of resistance, then engage the filament guide once
again. Sometimes the guide may need to be adjusted a bit, this is done with the two thumbscrews on the left hand side of it.
6. Confirm in the panel that the filament has been loaded. The machine will feed some through, let it finish then discard the excess filament it fed through.
7. With the filament loaded, you can either load your sliced file into the Cura install on the printer laptop, or attach your own laptop via USB with Cura set up for the Taz 6. Either way, once the filament is loaded, be sure your file is sliced, then hit ‘Send’ in the lower right corner of Cura. The printer will run through a homing and leveling process, then begin printing.
8. Watch the first few layers go down, as this can be a good indication if the print will have any issues. Making sure the first layer has good adhesion and doesn’t have any weird issues is always a good idea. After confirming this, the print will proceed as needed, and finish close to the estimated time given in Cura.
9. To unload filament, select ‘Change Filament’ again, and repeat the above steps until the filament is ejected from the print head. Now you can power the machine off and put the filament away.
Wanhao Duplicator i3
The Wanhao uses 1.75mm diameter filament, and has a bit smaller total build volume. To load filament
1. Power the machine on (switch is one back of control unit).
2. In the navigation menu, choose ‘Quick Settings’ -> ‘Preheat PLA’ or ‘Preheat ABS’, depending on the filament you’re using. Try to roughly match the nozzle temp to whichever material your filament is closest to.
3. Back out of the menu so you’re looking at the main screen. Here you can monitor the nozzle and bed temperature. Wait for the nozzle to heat to either 215C or 240C, depending on what you chose above. While the nozzle is heating you can get your filament ready and on the spool holder.
4. Once the nozzle is within a few degrees of its target heat, insert the end of your filament roll into the PTFE tubing. Don’t force it in, just put it in until you feel a little resistance.
5. In the navigation menu, select ‘Extruder’ -> ‘Extruder Position’. Turn the dial clockwise to feed filament into the hot end. This interface can be a little finicky, but stick with it a few turns at a time until you get a steady flow of filament out of the nozzle. Remove any of this extra filament, and make sure the print bed is clean (Isopropyl Alcohol and a rag work great for this).
6. Back in the menu, choose ‘Print File’. Be sure that the micro SD card is inserted in the machine with your sliced file on it BEFORE powering the machine on. If not, just shut the printer off and turn it back on with the micro SD in. In the ‘Print File’ menu, navigate to your sliced file (the newest file will populate at the bottom of the list, so just scroll down a bit to find it). Select your file, then wait for the printer to home and begin printing. If there’s any material ooze from the nozzle while it homes, feel free to carefully remove it with a pair of tweezers.
7. Wait to confirm that your first layer has successfully layed down. A lot of print issues can be solved by making sure the first layer adheres properly. After this, let your print run until it is finished. Watching the first several layers can often give a good idea of if there are any issues to deal with.
8. To unload filament, pre-heat the nozzle, and use the ‘Extruder Position to back the filament out until it can be pulled free from the PTFE tubing.
Machine Panel Options
All our machines can be tweaked and operated from the front panel. Some of these options are for advanced users and should be left as they are, and some are necessary to use the printer. Some of the more necessary options are:
Lulzbot Taz 6
Movement will allow you to Disable Steppers in order to move the build plate manually, andMove axis if you need to lift the Z due to a failed or problematic print.
Temperature controls the Nozzle and Bed Temp. if you need to set either outside of load- ing in filament. Cooldown will cool down both.
Configuration contains more advanced set- tings, and should not be changed.
Change Filament will allow you to change the filament, with presets or a custom nozzle temperature.
Print from SD will let you print directly from the SD card if you need to (it’s recommended to print from USB most of the time on the Taz).
Wanhao Duplicator i3
Quick Settings Preheat PLA/ABS will pre-heat the nozzle to the necessary temperature. Cooldown will cool down the nozzle and the bed. Disable Stepper will let you manually move the print bed, if you need better access to a part.
Print File is where you select the file to print.
Position X Pos., Y Pos., and Z. Pos will let you move the individual axes. Z. Pos is especially helpful if you have a failed print and need to get the print head out of the way.
Extruder Extruder Position is where you will control the loading and unloading of filament into the machine, after the hotend is heated.
Fan Speed this should be ideally left alone and controlled via Cura.
SD Card if you notice a print failure or need to restart a print, this menu will let you Stop or Pause the print.
The final two main menu options are for more advanced users, and should not be changed.
FDM Printers operate by applying heat specifically where it is required, and getting rid of it when and where it is not. Outside of other machine aspects (motors, control boards, motor drivers, etc.), this is the basic principle of printing. Much of this happens in the print head between the extruder, hotend, heat break, heatsink, heat block, thermistor, and nozzle.
Hotend is made up of several elements, all of which work together to apply heat directly to the filament to heat it to it’s glass transition point. These include:
Heat Break is the internal conductor of heat, which pre-heats the filament as it travels toward the Heat Block.
Heatsink is meant to rapidly remove heat from the hotend, so the heat is primarily directed toward the inner chamber where the filament passes through, and thermal runaway doesn’t occur. One or more fans are mounted near the heat break to help remove excess heat.
Extruder is what applies force to push the filament through the heated elements to the nozzle. There are two types (see next page).
Heat Block is the element which heats up via electrical resistance to provide heat to the rest of the hotend. This is also where the Thermistor is mounted, to keep accurate track of how much heat is present.
Nozzle is what the filament is ultimately fed through. Typical sizes range from .1 to .8mm openings, but for general use .4mm is extremely common.
heat the nozzle to the necessary temperature.
Extruder Types: The primary methods of forcing
filament into a hotend are known as Direct Drive
and Bowden. The primary differences between the
two lie in where the force is applied to the filament
in order to move it forwards and backwards
(extrusion and retraction). Direct Drive systems put
the applied force right next to the hotend. This gives
a mechanical advantage with filaments such as TPU
and to a degree PET/PETG, which can bind up easier
in a Bowden system, but the trade-off is it tends to make the print head heavier, meaning it can’t move quite as fast as a Bowden can. Bowden systems mount the gearing which applies the force somewher on the printer frame, and it is fed through a line of PTFE tubing to reach the hotend.
PTFE Lined vs. All-Metal: A difference between printer extruders is their material composition. PTFE lined extruders have a small run of PTFE tubing which feeds the material into the hotend in a low-friction environment. They ease the travel of the materail, but are more susceptible to the PTFE carbonizing over time, which then creates clogging issues if not replaced. All-Metal extruders solve this problem by using a a tube made of one type of metal to direct material to the hotend, and generally need less maintenance. Bi-metal hotends are tubes made of two or more types of metal, and are generally engineered to apply as much heat as possible to a mate- rial, whether because the material requires it or in order to speed up printing time. In a PTFE lined setup, it is important that the PTFE contacts the nozzle as directly as possible - if there is a gap between the two it can create backpressure, as well as creating a spot which is likely to start oozing out of the top of the heater block, both of which can easily ruin a print and are a pain to repair/deal with.
needed in a part.
Too much cooling. Layers don’t adhere properly and ringing/ layer shift are more likely.
Ideal cooling. Good layer adhesion, and the intended part structure is maintained throughout the print.
Not enough cooling. Parts will tend to warp and deform if they don’t just turn into a blob of goo.
Little or no gap creates an ideal printing environment.
Significant gap can create back pressure and overflow issues out of the heat block.
Nozzle Types: The most common nozzles are made from brass or sometimes copper, both of which have good thermal conductivity, but are more susceptible to wearing out. Hardened steel or Tungsten carbide nozzles are the better choice for abrasive filaments (metal or wood filled or containing Carbon particles), but conduct heat less effectively, thus require more heat from the hotend in order to print effectively.
Part Cooling: In addition to the fan(s) which help to cool the Heat Break, most all FDM printers will also employ one or more cooling fans to cool the filament once it has exited the hotend and nozzle. Ideal part cooling will allow extruded filament to adhere properly to either the build plate or the previous layer, while eliminating the likelihood of warping, drooping, or just an overall globbed up mess of a print. It also is key in maintaining dimensional accuracy where it is
Good part cooling will typically direct the cool air provided by a fan more towards the part itself than the nozzle. Some filament types will do better with less cooling as well (PETG for example).
There are a lot of variables in 3D Printing, and figuring out which specific one(s) are causing problems can some- times be a process. A few common problems, and potential solutions:
Filament not feeding correctly through the nozzle, or there is a big pile of goop
on the nozzle or hotend: This is usually caused by a clog in either the nozzle or the hotend. Nozzles wear out over time, and any residue left behind by a lower temperature filament can potentially carbonize when heated to a higher temperature than it is rated for, both of which can cause a clog. Often a clog can be resolved by heating the nozzle up, and using one of the cleaning tips to gently work the clog out of the heated elements. If this helps get the filament flowing again, it’s often a good idea to extrude a little filament to try to grab whatever was causing the clog, then let the hotend/nozzle start to cool down. As the nozzle is cooling, you can do a cold pull (manually forcing a little filament through at a reduced temperature) to help grab any other bits that were causing the issue. Alternatively, this can also be down to extrusion and retraction settings in Cura. If it doesn’t seem to be a clog but you’re still having extrusion issues, try raising your printing temperature and/or changing your Retraction in Cura (you’ll need to enable Advanced or Expert settings for the latter to be visible).
Elephant’s Foot, or warping at the bottom of a print, causing it to loose
adhesion with the bed: Another fairly common issue, this usually comes down to either Print Temperature, Bed Temp., excessive cooling on the first few layers, or Horizontal Expansion/ Speed. Essentially what is happening is that some parts of the print are cooling faster than others, at a rate which is causing noticeable warping. Printing a Temperature Tower can help you determine if it’s an issue with nozzle temperature, if that’s not it we recommend next decreasing your initial cooling, followed by increasing Speed incrementally and/or increasing Horizontal Expansion in small increments.
Print not sticking to the bed, or releasing mid-print: Different materials have different properties, and getting one material to correctly adhere to the print surface can be quite different from another. Sometimes using a little bit of hairspray, or a layer of painter’s tape on the print bed can help with adhesion. A good tip for ABS is to make a slurry out of a little bit of the filament dissolved in Acetone, and paint a thin layer of that on the bed. Glue sticks can help in a similar manner. This can also be a matter of print bed temperature. There are multiple ways to improve adhesion, if you are having an issue a Google search of your specific filament can often help solve the problem.
Poor layer adhesion: This will be apparent if there are small gaps between your printed layers. This can usually be solved through increasing the print temperature in 5C increments, increasing your layer height in small increments, lowering your speed, or reducing your cooling. Increasing Horizontal Expansion can also help, and playing with your Top/Bottom settings can if the issue is more prominent toward the bottom or the top of your printed part.
Stringing: This is what we call it when you get a bunch of small ‘strings’ or ‘fuzzies’ coming off of a surface which is meant to be smooth. This usually has to do with temperature and extrusion, printing an extrusion tower or extrusion test is the first place to start (Google is your friend here).
Ringing or layer shift: Ringing is when the individual print lines of each layer are more pronounce than usual, and layer shift is the extreme end of this, when a layer will noticeably shift from where it should be. The primary culprit in both is usually Speed - when the print head is moving so fast that the motors may skip steps, or the GCode may lose track of correct head positioning. Sometimes fast head movement is ideal, but if you’re having either of these issues, try reducing your speed, and potentially reducing your printing temp. a bit as well to compensate.
‘Bubbles’ in print surface: There are two main reasons you may see this occur - either the filament is being heated too much in the hotend, or it has absorbed too much moisture by
being improperly stored. All polymer filaments are at least a bit hygroscopic - meaning they like to absorb moisture if it’s available in the atmosphere they’re stored in. You can usually tell if a filament has absorbed too much moisture, as it will become excessively brittle the more moisture it absorbs. Filament spools can sometimes be resuscitated by being run through a drybox - really just a dehydrator for filament. This problem will be much less prevalent if filament is properly stored when not in use - in an airtight container with dessicant pouches. Out of all the filament types, PLA, Nylon, PVA, and ABS are the most hygroscopic, while HIPS is among the least.
Bed Leveling: If you’re having issues with your first layer not laying down properly, chances are it could be a calibration issue having to do with bed leveling. The Taz 6 will auto-level, but even auto-leveling beds still need some occasional hands-on to maintain that level. If you suspect one of our print beds is getting out of level, please let us know ASAP so we can address the issue promptly. Not all printers feature knobs on the print bed for manual bed levelling, but it is becoming a more common feature. The Wanhao does have leveling knobs located on the underside of the print bed. If you ever suspect the bed is out of level, you can check by running a leveling test print (a search on Google or on your 3D model repository of choice can help you find one, generally it’s a single layer grid pattern which is layed down). This test print can show you if there are any areas of the bed where the filament is not properly adhering (whether it’s not sticking down, or is not laying down a continuous bead of filament). It’s normal for beds to sometimes have small, micro valleys in spots, these are more difficult to solve for with bed level and will require more of a Slicer-based solution. If one side or one corner of the bed appears out of level, that can be easily solved by bed leveling. To level the print bed, you want to get a sheet of regular paper, and move the nozzle from one bed corner to the next, after Homing the nozzle to it’s set Z axis home height. At each corner, you want the paper to be able to slide between the nozzle tip and the bed without interference, but not have any further gap than this. It’s a good idea to get a little interference, then back that off very slightly until the paper can slide cleanly between the two. Each corner will have a knob below it to adjust the height up/down. Doing this at each corner will suffice for setting the bed level. Many more modern printers can auto-level the bed with a mesh leveling process, we will update this guide as needed to cover that. Please also make sure there is no filament deposition on the nozzle prior to leveling, as this will throw the process off.
Bridging is the term used to describe a strand of filament layed down between two points, without the need for support underneath it. Long bridges can be difficult to achieve, but with sufficient part cooling they’re made easier. Ideal part cooling will blow cool air just below the printer nozzle, so that the layer being printed can sufficiently adhere to the one under it, but isn’t so hot that it wants to sag or warp.
Overhangs and Support are directly related. An overhang is when a printed layer lies outside of the layer beneath it - a general rule of thumb for over- hangs is that they’re fine up to 45 degress, and any- thing over 60 degrees definitely requires a support structure. The 15 degrees in between can vary from material to material, but Cura is fairly good at guess- ing this.
Alloys and Material Science It used to be the case that filaments could be divided among clear lines between different types of material, but with the popularity and ease-of-use of PLA, it has recieved a lot more attention in terms of R&D. What this means is that there are now multi- ple alloys and specific formulations of PLA which can perform near the thermal and toughness properties of other materials (ABS, PET, etc.). If you have a specific use case which requires a particular material, then obviously that material is best suited to your use, but if you’re okay with approximate performance you can often get good results out of a PLA Pro or PLA +, which tend to be easier to print with. Higher temperature and more industrial materials like Nylon, PC, and Carbon filled still have their own unique benefits, so the playing field hasn’t been entirely leveled.
Bed Adhesion: Some filament types tend to require specific aids in adhering to the print surface. These may include: painter’s tape, kapton tape, hairspray, glue stick, a slurry made of the filament material (mostly ABS for that one). Other, more advanced solutions include PEI coated sheets, Buildtak or similar sheets, G10 Garolite, and other sheet goods which can be cut to a bed’s specific size and held in place with binder clips while the print is running. Some materials can bind to specific build surfaces much more permanently than others (glass build plates like the one on the Taz 6 are more susceptible to this), and damage the print bed when removed. If you’re unsure about a specific material, please google it before printing to see if it requires any special treatment for proper bed adhesion.
SLACK We’ve tried to build this guide to be as comprehensive as possible, while still maintain- ing enough brevity that it’s not strictly a technical manual. With so many variable present in the world of 3D Printing, we heavily encourage new users to use our Slack workspace if they are having issues, or have any questions they’d like answered. We also don’t always have all the answers, so we highly encourage people to utilize their search engine skills if they’re having a particular problem.
Thanks and Happy Printing!