9. Alternate print surfaces

The Prusa PEI spring steel sheets are amazing. Simply put, for most PLA or PETG printing, you’re going to be hard pressed to find a surface that is easier to use once you master :REF:`adhesion <bed_adhesion>`. Unless you are printing exotic materials, learn to effectively use the PEI surface first. Then, once you’re familiar with its limitations, try others. Here are a few I’ve tried.

Note

These notes are based on my experiences with the Prusa i3 Mk3 and Artillery/Evnovo Sidewinder X1 printers. If you are using a different printer, please verify the hardware details are similar.

9.1. Prusa PEI

The Mk3 is currently shipping with the dual-sided spring steel sheet with smooth PEI sticker surfaces. This is an excellent all-around surface for most consumer-grade printing, and is my overall favorite. Properly cleaned and with Live-Z properly calibrated, nothing else is needed to obtain quality prints.

PEI is a fascinating material that grips extremely well at higher temperatures, but releases prints once cooled. The PEI sticker can be damaged, but should last a long while with proper care. Small bubbles will appear as parts are removed, but will work their way out with heat over time. Higher-temperature and extremely sticky materials can stick too well, tearing the PEI surface. The PEI can be replaced, but it is a messy process. Unless you really like the strong citrus smell of Limonene, simply buying a replacement Prusa spring steel sheet with PEI surfaces already applied may be simplest.

Prusa also produces a textured powder-coated version that is – at least as of this writing – only available to those who ordered it with their printer prior to (roughly) April 2018. Prusa has moved production in-house and is working to produce sufficient volumes to offer this surface for general sale, but right now, it is a hard-to-find item.

The textured PEI surface offers excellent adhesion, but its most compelling feature is the textured surface it produces. This is what Prusa uses to get the interesting texture on the Mk3 parts printed in PETG.

Fig. 9.1 The elusive Prusa powder-coated textured PEI spring steel sheet

In addition to the interesting texture, the surface also has excellent “grip” on most filaments, and may be a bit more forgiving of poor upkeep.

9.2. BuildTak

BuildTak is an alternative to PEI with a grainy texture. Unlike PEI, it is meant to grip prints well even on unheated beds, making it a favorite on economy printers. As a result, it may grip very well and not let go, even once cooled. It can be useful for some exotic materials. BuildTak is a consumable, so expect to replace it.

Caution

BuildTak is not PEI. Do not use acetone on it or you may wind up with “BaldTak”. Acetone will strip the texture and damage the surface, even in small quantities.

BuildTak sells their own version of the spring steel flex sheet. The sheet works well, but I find it considerably stiffer than Prusa’s version.

BuildTak spring steel sheet with original BuildTak surface — Fig. 9.2 BuildTak flex steel sheet with original BuildTak surface

BuildTak also sells PEI adhesive sheets. BuildTak uses an adhesive that is considerably easier to remove and clean up than the 3M adhesives used for most surfaces. A sheet with BuildTak on one side and PEI on the other can be handy for printing with experimental materials. Be sure to research any materials and use proper bed preparation before starting a print. If you do suffer a disaster that damages either surface, it can be replaced relatively easily thanks to the BuildTak adhesive.

Fig. 9.3 BuildTak spring steel sheet with BuildTak PEI surface

Printing on BuildTak produces a sandy-looking bottom layer.

Fig. 9.4 Bottom layer results on BuildTak

9.3. Fake BuildTak

A number of manufacturers produce “fake BuildTak” surfaces, particularly the low-cost printers from AliExpress, Banggood and similar offshore sources. These tend to be poor copies, and wear out quickly in comparison to the real deal. Still, they might be useful in a pinch. Fysetc sells such a surface inexpensively. I haven’t worked with it much, but do have it handy for an emergency.

Fysetc "slab steel" cover sheet with fake BuildTak surface — Fig. 9.5 Fysetc “slab steel” sheet with fake BuildTak surface

Fysetc also produces a “spring steel” sheet. In my experience, this thing is not spring steel, and will tend to stay curved if flexed. It is also heavy enough to remove a toe if dropped. Mine is so thick I have a very hard time finding a usable Live-Z value for it. Some users report good results with the budget sheets from AliExpress, but I find more reliable versions well worth the additional cost.

Fysetc "slab steel" sheet — Fig. 9.6 Fysetc “slab steel” sheet

9.4. Textured vinyl

If you’re in the mood to experiment, or absolutely must have a textured surface now and can’t get your hands on a Prusa powder-coated sheet, you can get some good textured prints on textured vinyl. This is limited to PLA exclusively however. I was not able to get anything other than PLA to print without damaging the vinyl. There are a variety of surfaces available, including basic pebbled, leather, concrete, carbon fibre and high-tech matrix patterns. I had good results using 12x12 inch 3M 1080 wrap samples.

Fig. 9.7 PrintedSolid spring steel sheet with textured vinyl wrap surface

PLA adheres very well to textured vinyl, requiring now additional adhesion measures on a 55C heated bed.

Fig. 9.8 PLA adhesion to textured vinyl

Bottom layer results are interesting, and a variety of textures are available.

Fig. 9.9 Bottom layer results on textured vinyl

Fig. 9.10 Comparison of bottom layer results on textured vinyl surfaces

Texture vinyl is definitely a consumable, and very easily damaged compared to most other surfaces. Fortunately, it removes easily for replacement.

Fig. 9.11 Removing textured vinyl from flex steel print sheet

9.5. Alternate spring steel sheets

PrintedSolid is selling cost-effective bare spring steel sheets for the Mk3. These are considerably thinner than the Prusa sheets, and quite springy.
PrintedSolid is also offering a version with the Gecko Tek surface, but I personally don’t see the advantage for the price.
PrintedSolid recently added “THEKKIINNGG” textured sheets – also available on eBay and Amazon – which I have not tried.
MatterHackers is selling their Layer Lock powder-coated PEI surface which is compatible with the Prusa Mk3. I have not tried this.

9.6. Alternate surfaces

In addition to the surfaces noted above, other surfaces are available.

Ultem/PEI adhesive sheets in a variety of thicknesses can be ordered directly from CS Hyde. Order large and trim down to fit your sheets.
FilaFarm sells their FilaPrint surface for the Mk3 which is widely praised. I have not tried this one myself.

9.7. Print surface recommendation

My personal favorite combination is a PrintedSolid steel sheet with BuildTak PEI. It’s light, very flexible for easy part removal, and the BuildTak adhesive will allow easy replacement if damaged. I’m using a combination of original BuildTak on one side and BuildTak PEI on the other for my “hot and sticky” filaments. However, this is defintely a “nice to have”, not a requirement. The stock Prusa smooth PEI surface is extremely flexible and effective for most printing needs.