As known to all, initial layer adhesion is critical for FFF 3D printing, on which we would spend a lot of effort, such as tuning the slicing parameters or using various tools. That’s also why Snapmaker specially designed a detail-rich print sheet to minimize the troubles. Now, let’s take a look at this product and learn some basic daily maintenance and cleaning skills.
Design & Material
The print sheet of the Snapmaker 2.0 machines consists of two parts: the steel plate and surface stickers on both sides.
The steel plate is made of carbon steel with high toughness and strength. Though the print sheet can be bent slightly, it will immediately return to its original flatness once the force is stopped, thus ensuring that the entire printing platform can always be kept flat during printing. At the same time, its magnetic design also provides great convenience for removing prints and replacing the print sheet.
Although not fixed with screws, the strong magnetic attraction between the print sheet and the heated bed helps them stick firmly together. Without intended human force (which must be very strong, actually), the print sheet will not move during printing.
The sticker of the print sheet is made of polymer materials, of which the surface is specially processed to further improve the adhesion effect of the initial layer. Though named as “sticker”, it is highly flame-retardant, oxidation-resistant, as well as heat-resistant.
Thanks to its material properties, the print sheet sticker can effectively accelerate the cooling process of the extruded filament when the initial layer is printed, making it adhere to the print sheet faster and better, and also reducing the possibility of wrapping. Internal tests have shown that our specially designed sticker can effectively improve the initial layer adhesion of a wider variety of filaments, compared with the Polyetherimide (PEI) stickers or coatings used in many other printing platforms.
Moreover, the print sheet of Snapmaker 2.0 has stickers on both sides. This not only ensures the flatness of the steel plate when heated, but also increases the utilization of the print sheet. You can switch the front and back sides at will to use, thus reducing the frequency of replacement.
How to Avoid Print Sheet “Injuries“
Traces or marks may be left on the print sheet due to various reasons over repetitive use. If not handled in time, they can affect the printing quality. For example, filament residues on the print sheet may negatively impact the initial layer adhesion in the next printing. What’s more, if filaments of different colors are used over two successive printings, the bottom of the latter print is likely to be branded with an undesirable “gift” from the former print, as shown below.
Also, dented traces pressed out by the nozzle on the print sheet may leave some “3D tattoo” on your future prints.
Some of these traces are reversible and can be erased by later cleaning, while others are permanent. Therefore, before we proceed to cleaning methods, let’s go over some preventive measures and precautions that can help you avoid such “injuries” to the print sheet.
- Don’t set the Z height too low.
Many Makers, including myself, tend to set the Z height as low as possible during the heated bed leveling or after the printing starts, so as to reduce potential problems that can happen to the initial layer adhesion. However, the nozzle can easily leave dents on the print sheet in doing so. At the same time, the extruding of filament may be hindered or even stopped if the nozzle is too close to the print sheet, which could give rise to discontinuous lines, uneven surfaces of the printed object, or even nozzle jams. A failed printing process can be restarted, a jammed nozzle can be cleaned, but the dent left on the print sheet is irreversible. What’s more, an excessively low Z height may cause the filament to stick too much to the print sheet, bringing about more troubles in the cleaning process afterward.
- Don't take out or elevate the print sheet when the machine is still working.
Sometimes when the printing of the initial layer is not going well and thus you decide to remove the filament and start over, you might just take out the print sheet directly without pausing the machine. In this case, the distance between the nozzle and the print sheet will suddenly decrease, and the nozzle may leave dents or traces on the print sheet as a result.
- Use masking tapes on the print sheet.
As one of the favorite tools among Makers, masking tapes can improve the adhesion of the initial layer. Every time before a new print, you can just conveniently tear the old tapes off and apply new ones. More importantly, they won’t damage the print sheet. If your print sheet already has traces that can affect printing quality, you can cover them with masking tapes to minimize their annoying effects.
There are things you should pay attention to when using masking tapes:
- Do not overlap masking tapes, for the nozzle may lift the overlapped part of the tapes when printing the initial layer. Beyond that, take special care when sticking the edges of masking tapes. When the 3D printing module finishes heating and moves from the bottom left of the print sheet to the target area, it may easily scratch up the edges of masking tapes.
- The area covered by masking tapes should be larger than the printing area; otherwise, the nozzle might also scratch the edges of the tapes.
- Level the heated bed again after applying the masking tapes before printing. This is because the tape itself has a certain thickness, so printing without a second leveling may cause extra problems.
- Apply washable glue to the estimated printing area on the print sheet before printing.
Note that one or two thin coats of glue are enough, and make sure the glue is applied evenly to avoid lumping. When the printing is completed, you can easily remove the glue traces with water and a towel. Besides, it’s better to clean the glue immediately after printing when the heated bed has not cooled down, or you can clean the glue with warm water.
- Set the Line Count to 3 or above if you choose Skirt as the Build Plate Adhesion Type in the slicer.
Setting the build plate adhesion type helps enhance the initial layer adhesion, but when you select skirt and set the line count to a value smaller than 3, there are chances that some filament residues would stick to the print sheet and be difficult to remove.
We have collected some practical cleaning tips from our colleagues and forum, which can be roughly divided into physical and chemical ones. When there are filament residues or grease on the print sheet, you can try some of the methods below.
You might be wondering: Nobody cooks on the print sheet, so where does the grease come from?
In fact, our skin produces natural grease that might stick to the print sheet while we operate the 3D printer. Besides, dust from the air can also fall on the print sheet. The accumulation of grease and dust over time will inevitably affect the adhesion performance of the print sheet. Therefore, we need to clean the print sheet regularly, even if there is no filament residue. If you print frequently, it’s best to wipe the surface of the print sheet with a clean towel after each printing.
The simplest and most effective physical method to remove filament residues is as follows.
- Heat the heated bed to a temperature above 70℃ (gloves are suggested to protect your hands).
- Clean the print sheet either with the palette knife in the Snapmaker tool box, or with a similar plastic tool.
Be careful about your force in the process so that the palette knife doesn’t damage the print sheet. It’s recommended that you hold the front part of the knife with great care, concentrate the force of your fingers, and slowly clean the residues.
The palette knife might leave some tiny scratches during this process, which are tolerable as long as they don’t affect the flatness of the print sheet.
Actually, we don’t recommend that you use the chemical method. As mentioned before, the surface of the print sheet sticker is specially processed for better adhesion performance. However, the chemical solvents may damage the surface. Therefore, use the chemical methods as a last resort and with caution even if they can help sometimes. Only when the physical method doesn’t work and you have no other print sheets for replacement can you try the chemical ways.
According to tests, the 70% (or above) isopropyl alcohol (IPA) may help remove filament residues yet must be used in a well-ventilated area with protective measures. Additionally, ensure the heated bed has cooled down when using this method because the IPA is highly volatile.
It should also be noted that for filament residues accumulated for a long time, neither physical method nor chemical method is of much help. Therefore, it’s better to clean the print sheet after each use.
If one side of the print sheet cannot be used anymore, switch to the other side. If the damaged side is uneven with filament residues, you need first remove the residues before switching, or the flatness of the print sheet could be influenced. If both sides of the print sheet are damaged, you can place an order at our official store for a new print sheet with a few clicks!
We hope this article could be useful for you!
In the future, Snapmaker Academy will bring you more fun topics, so stay tuned!
If you are interested in other content of 3D printing, feel free to contact us at firstname.lastname@example.org or leave your message in the community.
All the methods in this article are for reference only.
Snapmaker does not assume responsibility for loss, injuries, damage, or expense arising from or in any way connected with the methods in this article.