Explore 3D

13 Tips and Tricks to 3D Printing

Johann Wyss

Issue 20, March 2019

Whether you’re just starting out with your 3D printer or you want to learn how to get better results from your prints we’ve got some great tips and tricks for you to try.

3D printing is an extremely fun and rewarding hobby. There is no better feeling than starting a project with an idea and ending with a product in your hand a short time later. It can, however, be a very frustrating hobby due to it’s sometimes steep and relentless learning curve. Hopefully, we can help alleviate some of the newbie issues you’re likely to encounter and in turn make your introduction into 3D printing that much easier and more enjoyable.

Tip 1:

Safety First

printing

It is important to be safe around 3D printers and to also have a safe environment for your printer to operate in. For the most part, 3D printers are no more dangerous than many other electrical devices you use daily in your home. There are, however, a few points that you should be aware of when you begin your foray into the 3D printing world.

DON’T LEAVE YOUR PRINTER UNATTENDED.

3D printers provide very little feedback while they operate. The printers usually have no way of telling if they are working correctly or if they are turning your build platform into a plate of spaghetti. It is best to keep a constant eye on your printer.

Incidentally, this minimal feedback also has the potential to cause injury to anyone who puts their body parts into the build area. In the vast majority of cases, 3D printers are not designed to detect if they are obstructed. This means you should keep your hands and fingers, etc. well away from the machine if it is operating. The build area of a machine moving 200°C+ blocks of metal around at 50-200mm a second is not a place one should want to put their fingers.

SMOKE DETECTOR

By their very nature, 3D printers have moving parts that heat to high temperatures to melt plastic (The filament). We strongly encourage anyone involved with 3D printing to install a smoke detector in the room they use for 3D printing. 3D printer fires are not common thankfully, however, you should be prepared in case your printer unexpectantly fails. Smoke detectors are quite inexpensive, so it’s good peace of mind to have one.

VENTILATION

Recent studies have shown that 3D printing can produce airborne particulate matter which humans are capable of inhaling. It is good practice to keep a well-ventilated work area i.e. keep a window open while your printing for some fresh air.

SCRAPER

A common injury you see with 3D printing enthusiasts is small cuts to their hands and arms caused when removing the print from the print surface using a scraper and brute force. To avoid injury, we recommend you leave the part on the bed until the bed cools. As the bed cools it will shrink slightly, which will help the part to release.

If you simply must have a part removed off the bed in a hurry, keep a can of freeze spray on hand. A quick blast of cold liquid/gas on the base will usually cause the part to unstick quickly (Compressed air works too, just invert the can!). Caution: Freeze spray is generally fine with glass beds too, provided the manufacturer is using glass designed to be heated. i.e. borosilicate glass. Borosilicate glass is the only glass you should be using as a heat bed because it is doped with boron trioxide to give it a much higher tolerance to thermal shock. If your printer has a glass bed, make sure you check it is proper borosilicate glass before using a cold spray as the sudden thermal differential is likely to cause standard glass to crack violently.

Tip 2:

Keeping it Clean

glass

Pay close attention to your printer’s build surface. The build surface is the material that holds your print while it is being printed. It is easily one of the most vital components for successful 3D printing, yet it is without a doubt, the most neglected component. Keeping it clean and damage free should make your 3D printing experience much better. The two most common build surfaces today are PEI or glass.

PEI

Most printers today come with a PEI (Polyetherimide) sheet, which is a textured build surface designed to promote adhesion. Long term use of a scraper on this PEI sheet often results in a reduced adhesion as the textured surface is damaged. This is another good reason to keep away from the scraper. We also highly recommend you use Isopropyl alcohol before each print to clean the build surface. This will help to remove dust, oil and other contaminants, providing much better adhesion.

You can usually purchase replacement PEI sheets if your PEI base gets scratched.

GLASS

We prefer to print directly on glass, especially when the surface touching the build plate is a visible part. Printing on glass often produces a very shiny and smooth bottom layer, which is very appealing in some cases. Glass can be difficult to get good adhesion when compared to PEI, so it requires very careful leveling and a good clean with Isopropyl alcohol. With some trial and error, you will soon learn how to produce consistently great results.

PRINT BED TAPE AND STICKERS

There are various tapes and stickers you can use to apply to your print bed to help improve the adhesion force between the filament and platform.

Kapton tape and BuildTak are just some of the options available. The options vary from round or square adhesive sheets, adhesive tapes or magnetic plates.

You would need to test these to see what works best for your printer.

Tip 3:

On The Level

on the level

Keeping the printing bed level is very important. The common cause of poor bed adhesion for beginners to 3D printing is a failure to get the bed level and sufficiently close to the build surface.

We use a business card or a folded A4 sheet of paper to level our printer beds. This is done by homing your printers Z axis, so the nozzle is at its starting position. We then insert the paper/business card between the build surface and the nozzle. Using the thumb screws we raise or lower the bed height so that there is resistance on the paper. You don’t want there to be too much resistance. You want it to be close enough just before the paper wants to bend rather than slide under the nozzle. We do this at every thumbscrew in a circular pattern two or three times before starting a print.

Fortunately, many 3D printers on the market now include automatic bed leveling technology. The Lulzbot Mini 2 and TAZ 6, for example, have a fully automatic leveling feature that runs before each print, which means you never have to worry about bed leveling.

FlashForge also tackled the bed leveling issues by producing a guided leveling process, in which the printer moves the print head above the thumb screws and instructs you to raise or lower the bed until it detects it is level. Both technologies make it significantly easier to level the bed and get great prints.

Refer to the user manual for your printer to see what bed levelling procedure it needs.

Tip 4:

Provide Support

support concept

Pay attention to the support material. 3D printers operate by depositing a very fine bead of molten plastic onto a surface to make the desired pattern. It then adds another layer on top of the previous, and repeats until the model is made. However, what happens when you need to print an overhang? That is, print a layer when there is nothing below it.

Take, for example, this file from Thingiverse. The printer will work perfectly fine for the two main structures of the bridge, however, when it prints the connecting piece there is nothing to support the layer. This will generally result in a “sagging” appearance, and in some cases, a complete print failure.

This part without support took 18 minutes to print. As you can see in the resulting pic, the printer had significant issues bridging the gap between the two towers unassisted. This could be reduced by lowering temperatures of the hotend, reducing how pliable the material becomes, however, that will also affect the quality of the entire print.

To counter this, we can use what is called support material. Various slicers offer different options for support. The support is essentially an object that is printed under to model overhang that the model is printed on. This support is then removed after printing. This, of course, adds to the printing time and also the print clean up because support generally leaves scaring on the print surface (Usually easily resolved with sanding or cutting with a exacto style cutting knife). To solve this, many slicers have adopted tricks or tactics to minimise the support material and its contact with the print.

CURA

cura 2

Cura has custom supports which allows you to place minimal support material by placing it only where you want. This can help reduce scaring of the mating surfaces and also saves significant printing time. You can see the bottom of the print has a bit of scaring, however, it can be repaired quite easily with a little sanding/finishing. This print with linear support structures took 26 minutes to complete.

Flashprint

Flashprint, like Cura, has custom supports, however, it also has “Treelike” support structures. These provide a very small contact with the print, thus significantly reducing the cleanup time. However, as a tradeoff, “treelike” support material takes significantly longer to print in some cases. It does take significantly less work to clean up though, compared to the linear type supports. This test piece using “Treelike” support structures took 45 minutes to print.

There are pros and cons to support material. The part can look nicer when using supports compared to without, however, there is a fairly significant cost in time when using them. The best option is to design or orient the print to require minimal support. Learning to use your slicer support settings will certainly help you achieve great results.

There are many good .stl’s on Thingiverse that allow you to test how far your printer can print with overhangs. Search for “overhang”, “Bridging” or “torture test” and do some experimenting with your printer’s capabilities. This will help you learn the best ways to orient prints to reduce the need for support, which will result in quicker prints, less post processing and less visible scarring on your printed object.

Tip 5:

Build a Raft

Learn when and how to use to use rafts. Rafts are essentially a buffer between your build surface and the object you are printing. It allows you to increase your chances of a successful print, despite your bed not being perfectly level or close enough to the bed.

To demonstrate this, let’s print a Cali Cat or calibration cat from Thingiverse. If we were to print this at 0.3mm layer height, we would likely have very little issues. If each filament layer extruded was 0.3mm thick, that gives us quite a bit of room for error i.e. differences in level, etc.

If we print this at 0.08mm, suddenly the bed level and consistency become significantly more critical. In these situations, we recommend using a raft. A raft will significantly increase your success rate when printing at ultra-fine and high-quality resolutions. It wastes very little plastic, especially once you consider failed prints.

The tradeoff to using rafts is that there will always be scarring on the mating surface, as you can see on the underside of this print. Therefore, I suggest you avoid using rafts if you need to print the face of your print oriented flat on the raft surface i.e. the side most visible flat on the print surface. If the situation demands the part to be printed face down, and you need the ultra-fine resolution, you may need to think carefully about other options in your slicer such as variable layer heights etc.

Tip 6:

Slicing it up

Our sixth tip is to tinker with your slicer. Don’t be afraid to experiment with various slicer settings. You can’t really damage your printer by getting something wrong in the slicer (careful with temperatures though, PLA can carbonise in your nozzle at temps over 220°C, which can easily lead to clogging and poor prints).

We recommend you keep a backup of your known working settings, along with a known good Gcode file so you can always revert if it all goes horribly wrong.

You can also use the known good Gcode to eliminate mechanical issues. i.e. If you can’t seem to get good prints suddenly, print the known good Gcode. If it prints poorly then you know that there is a mechanical fault at play and not a software setting (The Cali Cat model is perfect for this).

We strongly encourage you to practice with the aforementioned variable layer height. Learning this will allow you to change the layer height at various stages through a print. This can be used to achieve awesome quality prints that don’t take days to make.

Take, for example, if we were to print this Torana from Thingiverse.

If we were to print it using a 0.3mm layer height, including support material, it would take about 15 hours to print. However, at that layer height, you will see significant banding along the horizontal curvature of the print as shown in the above image.

One option is to simply print the model in a higher resolution i.e. a lower layer height. However, this significantly affects the print time. A 0.2mm layer height takes twice as long as a 0.3mm layer height, which means if you were to print the same model in an ultra-fine resolution of 0.08mm it would take something like 50 hours to print!

Therefore, the best option is to use the variable layer height options in your slicer eg. adaptive layer height in Cura. You can set the curved horizontal layers to print at an ultra-fine resolution while having the rest of the print utilize a much lower 0.3mm layer height. This will allow you to get superb prints without waiting a lifetime for them.

Tip 7:

Applying Heat

fire

Get yourself a hot air gun to quickly and easily remove blemishes and fine stringing from your printed part.

To demonstrate this, we downloaded a Stringing test from Thingiverse and change our slicer settings to exaggerate stringing issues (This can be done by printing at a higher temp causing the filament to ooze as it travels and or by reducing the retraction in the slicer etc.)

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As you can see in the results in the following image, there is some significant stringing as the print moves to the next location.

heat applied
wrapped print
Too much heat can warp the print.

With a quick flick of the hot air gun, we can remove the vast majority of this stringing and be left with small globules which can easily be scraped off with an exacto style knife.

Likewise, the hot air gun can be used to clean up the blemishes left from support material and rafts. You simply remove the support material and give the effected area a once over with the heat. Be careful, especially with smaller parts as they are very easy to melt and warp with the heat from a hotair gun, which will ruin them.

scratches
Panel before heat treatment removed most of the blemishes.

Supports and rafts are not the only things that leave blemishes on the surface of your prints. Take, for example, our Lolly Sorter from Issue #019. It was printed face down on the PEI build surface. Whilst it was a fairly level and smooth print you can see some significant white blemishes across the surface. Giving the print a once over with hot air removes 90% of this blemish, resulting in the finished product you see in the magazine.

Tip 8:

Fresh is best

wire

It’s recommended to avoid stockpiling too many filament colours, even if you own a dual extruder printer. Many 3D printer filaments can be affected by temperature and humidity over time. PLA filament, for example, is a bioplastic and can be made from organic plant-based materials, such as corn starch or sugar cane. This means that it can easily absorb water.

Using filament that has changed in composition can produce poor quality prints, or even worse, damage your printer. Generally, filament should be used within 12 months from opening the factory sealed pack. If you must keep a quantity of filament on hand, we recommend you build a filament storage container. An airtight container with desiccant (moisture absorber) would be ideal. An alternative is to use a vacuum sealed bag with double-zipper with moisture absorber.

You could easily use the inexpensive storage containers you find at shops like Kmart and use moisture absorbers preferably with “rechargeable” desiccant, which will help keep your filament as fresh as possible for as long as possible.

damp rid

Note: Some people use rice as a moisture absorber, but this is not as reliable as commercial moisture absorbers.

Tip 9:

Orientation Matters

hand print

Be mindful of how you place objects on your printer build platform.

Your placement on the platform will have a direct correlation with the strength of the finished product, the amount of support needed and even the quality of the print.

This all comes down to the layer by layer nature of 3D printing, and more precisely, the nozzle diameter you are using. Most 3D printers today come standard with a 0.4mm nozzle, which means the material deposited will be 0.4mm thick. However, our z-axis/layer height has a resolution as fine as 0.08mm.

Therefore, to get the highest quality prints, especially in relation to fine details, you want the details to be along the z-axis.

Take this awesome bust of Nikola Tesla for example.

In this case, we certainly want to print it in the native orientation, all of the important detail we want to capture is in the Z axis.

x axis print
X Axis Print
y axis print
Y Axis Print

The individual layer height here is .2mm or half of the nozzle diameter, if we were to keep all the settings the same and simply rotate the model so the fine details that we want to print is in the x y plane we can see the nozzle diameter has distorted much of the detail we wish to capture.

Obviously, this isn’t the best example as one would intuitively decide to print a bust in the vertical orientation however it serves the purpose of explaining the issue. The take home should be that fine details are best printed using the layer height and not the much larger nozzle diameter.

With that said the quality of the print is only a small part of why orientation of your part matters. Let’s say you wanted to print a mechanical part. Something which required a load to be placed upon it. The way you print this item will have a serious impact on the strength and therefore load capacity of the item.

Let’s take for example a Nema 17 Bracket from Thingiverse.

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Vertical Orientation Print
Vertical Orientation Print
Horizontal Orientation Print
Horizontal Orientation Print

There are several ways you could print this part. In its vertical orientation as seen above the print will require support material to protect the overhangs which makes this orientation less than ideal however there is also a significant problem for the part’s overall strength.

In this orientation, the layer lines which form the weakest bond are across the part directly where the downward force is applied. This orientation would result in a weak bracket.

This horizontal orientation will result in a stronger part, which is quicker to print and requires less material than the previous orientation. So be mindful of what your part is intended for and orient it to suit the task.

Tip 10:

Repositories

computer

Source actual 3D printable models. Not everything you find on the web in .stl format is 3D printable. For best results, we strongly recommend you only print objects which state or show that they can be 3D printed. There is nothing worse than finding an awesome model and struggling for ages to print it only to later find the source of all your frustration was a model not being optimized for 3D printing, ie not a solid object or containing holes etc.

Also, don’t fall into getting all your files from one place otherwise you may miss out on some fantastic designs. There are a bunch of awesome sites to find 3D printable models.

tag

Our top recommended places to find printable .STL’s are:

THINGIVERSE.com

Whilst not everything you find on Thingiverse is 3D printable the vast majority are. More importantly, you can see how it prints before downloading as most people have images of the printed object on their listing.

PINSHAPE.com

Pinshape has a mixture of free and paid .stl’s on the site. We find it is much less likely to find faulty FDM .stl’s here however due to its relatively young age it isn’t quite as large a selection as Thingiverse.

DIYODEmag.com

All the projects you see in the magazine can be downloaded for free from the Diyode website. This means you can get 100% known working .stls as you have seen them printed in the magazine already.

YOUMAGINE.com

Youmagine is another great 3Dprinting repository full of working .stl files. It has a very active community and the site is not as prone to slow down as some of the others.

Tip 11:

DESIGN YOUR OWN

Printing other people’s designs is lots of fun and will teach you a metric ton about the 3D printing manufacturing process. This is, however, only half of the rapid prototyping process.

To maximise your 3D printing potential, we encourage you to have a crack at designing your own rapid prototyping creations. It does not have to be complex. In fact, we encourage you to start simple. Make yourself a pen or phone holder to proudly adorn your desk using TinkerCAD and the tutorials in DIYODE.

Once you learn the basics, move onto other more challenging things. The best way to learn is to practice. In no time you can be making your own awesome creations to share.

Tip 12:

MAKE IT YOUR WAY

caliper

Once you start designing your own objects to print, use all the knowledge you learned printing 3DBenchy and Yoda heads to design the objects for printing. For example, keep in mind what angles print without any support. Try to design your objects to utilise that angle as much as possible to avoid the need for support material. You can also design your objects to use chamfers instead of fillets for your horizontal edges, which print much nicer and still look great. When you’re the designer, you get to make it your way and on your terms. Use what you have learned about the limitations of 3D printing to make anything you can dream of.

Tip 13:

HELP IS AT HAND

facebook

3D printing isn’t simple. It’s a very complex process that requires a lot of independent systems to work in unison. Things will probably go wrong. You will have failures (probably many failures). but you’re never likely to be alone. With the thriving 3D printing community there are plenty of resources to help you troubleshoot issues and get you back on the road to 3D printing success.

For example, nearly every brand of 3D printer has a Facebook group, full of other people with the exact same tool as you. These groups can be a goldmine if you’re ever having trouble. Probably nine out of ten others in the group have had the same issue as you and may have a way to rectify it.

Happy printing!