For beginners and experts alike, one of the trickiest aspects of FDM 3D printing is first-layer adhesion. Prints need to stick to the bed surface firmly enough to prevent the base from lifting up during printing, but not so firmly that they get permanently stuck to the bed.

This exercise gets especially complicated given the huge number of variables that affect bed adhesion. Different filaments have varying adhesive properties, while printing temperature, bed temperature, build plate surface material, use of adhesive agents like glue, and the use of rafts all affect how well the printed parts stick to the bed. Taking these variables into account, users must strike a balance between good adhesion and ease of part removal.

It’s not always a problem, of course. With a bit of luck and careful preparation, printed objects will stick to the print surface during printing and then pop right off the print bed once they’ve cooled down. Few sounds are more satisfying than the pop of a print detaching easily from the build platform after contracting slightly during cooling.

However, all printer users will experience an overly stuck print once in a while, and the situation needs to be handled carefully to avoid damage to the parts — or, worse, the print bed itself. This article looks at how to remove 3D prints from bed surfaces like PEI sheets, BuildTak, and glass beds, including those coated with adhesive agents like glue stick and hairspray.

Why bed adhesion matters

When it becomes difficult to remove parts from the print bed, the first instinct for beginner 3D printer users is a logical one: why don’t I just make the prints less sticky? Unfortunately, this often isn’t really an option.

Bed adhesion or first-layer adhesion is a critical part of the FDM 3D printing process. Without proper bed adhesion, parts can peel off the print bed and move around slightly during printing, leading to misaligned layers or total part failure. It’s why printer users go to great lengths — applying fine coatings of glue stick before every build, for example — to make their build surface adequately adhesive.

Getting the first layer right is equally important to good bed adhesion: this requires precise bed leveling and, in most cases, “squishing” the first layer down slightly onto the build surface.

Recommended reading: 3D print not sticking to print bed? Here’s the solution

Setting up a 3D printer for easy part removal

Before we look at how to remove 3D prints from bed surfaces — i.e. things you can do once the objects have already been printed — we should look at the different ways you can prepare your printer for easy part removal.

The two most important aspects to consider here are the flexibility or rigidity of the build plate and the build surface material.

Flexible vs rigid build plates

The build plate is a solid part of the print bed that can be removed from the build platform. Usually made from glass or spring steel, the build plate may or may not have a layer of another material on top of it acting as the build surface.

While glass build plates are common and highly affordable, flexible build plates such as those made from spring steel can make part removal much easier. This is because the build plate can be removed from the printer and bent slightly, creating a gap between the plate and the parts. If the parts have been printed well, they usually pop off the flexible plate with minimal effort.

That being said, rigid build plates offer some advantages. As well as being cheaper than spring steel, glass plates provide a very smooth bottom layer. 

Build surface materials

When trying to facilitate easy part removal, another important aspect to consider is the build surface material, which isn’t necessarily the same as the build plate material.

With a glass build plate, users often print directly onto the glass, though its surface is often coated with an adhesive such as glue stick or hairspray. Alternatively, it is possible to apply a layer of Kapton tape or painter’s tape over the build plate, though this sometimes creates unwanted air bubbles and difficulty removing the tape when it needs replacing.

Painter's tape can be used as a build surface

One of the most popular build surface materials is BuildTak, a proprietary product from Ideal Jacobs Corp, a commercial printing and manufacturing company from New Jersey. The build surface works with materials like PLA, ABS, HIPS, and flexible filament.

Equally popular is PEI (polyetherimide) sheet. PEI build surfaces are often textured to enable easier part removal, and they are also compatible with materials like PETG, which won’t print well on BuildTak.

Recommended reading: Tips to improve PETG bed adhesion

Heated beds

Heated print beds can result in better prints by minimizing warping caused by dramatic temperature changes.[1] They can also lead to better first-layer adhesion, which indirectly leads to easier part removal.

This might sound counterintuitive, as adhesion would appear to make the print more likely to stick to the bed. However, the advantage of the heated bed is that it can simply be turned off when printing is finished, effectively reducing the adhesion as the parts cool and contract. The same cannot be said of, for example, chemical adhesives like glue stick, which remain stuck between the parts and the build surface after printing.

Rafts

Using rafts is not part of the physical 3D printer setup, but it is another consideration that needs to be made before printing rather than after, being implemented using your slicer software.

A raft is a kind of flat support structure that is printed directly onto the build surface and on top of which the actual part is printed. It helps with bed adhesion and minimizes part warpage, and it allows you to be more vigorous if the part needs to be scraped off the build surface. This is because any potential damage from the scraping will be inflicted on the raft, which is disposable.

Cleaning the build surface

Keeping your build surface clean is a good way to improve first-layer adhesion while also making it easier to remove parts.

By removing gunk and residue from the build surface after prints, you improve the chances of natural bed adhesion; this in turn reduces the need to push the first layer too close to the bed, which can cause parts to become overly stuck.

Cleaning the build surface also prolongs its lifespan and improves overall print quality. 

Recommended reading: How to clean 3D printer beds: glass, PEI, adhesive

Methods of removing prints from the bed

This section looks at how to remove 3D prints from bed surfaces. It starts with quick and simple methods — usually sufficient for moderately stuck parts — and proceeds to more laborious solutions which typically only need to be used if parts are firmly stuck.

Many of these methods are surface-agnostic, though you are most likely to need them when printing directly onto a rigid glass bed. If printing directly onto the build plate (i.e. onto glass), it is best to wait for the parts to cool down before attempting any of the following methods: cooling causes the printing material to contract, reducing adhesion and making the parts easier to remove.

1. Bend the flexible build plate

The first method of removing parts from the print bed is only applicable when using a flexible build plate such as a PEI-coated spring steel one. It is one of the simplest and most effective means of part removal.

Many flexible build plates are magnetic and can be easily detached from the metal base. Once this has been done (with the parts still attached to the build surface), simply bend the plate slightly over a cushioned surface until the parts pop off.

2. Manually pull the parts

For rigid or flexible build plates, parts can sometimes be removed by exerting brute force. Use one hand against the build surface as leverage, and use the other to pull and pry the parts from the bed. This will only work if the parts are fairly large and simple; parts with thin and delicate features may get damaged if you try to yank them from the bed.

A word of warning: do not exert too much force while the build surface remains attached to the printer, as this can damage any clamps holding the build plate in place. If the parts do not detach with moderate force, remove the build plate from the printer then try pulling harder.

3. Cool the build surface

We have noted that parts will detach from the print bed more easily after the heated bed has cooled down. However, you can reduce the temperature further by removing the build plate and placing it in an even cooler environment such as a fridge. If you don’t have room in your fridge, rest the build plate on top of some ice packs. Try removing the parts manually (or with one of the following methods) after 10 minutes of cooling.

Ice packs can be used to cool the build plate

4. Use a scraper

If you struggle to remove the prints manually, use a flat tool like a paint scraper, spatula, or knife to get between the prints and the build surface. Companies like BuildTak sell dedicated scrapers for removing prints from the bed.

Although this method is more effective at prising the parts free than using your hands, it risks causing damage to the build surface, especially when using a knife. This doesn’t matter too much if you’re printing on tape, for example, but you certainly don’t want to be making cuts and scratches on your glass build plate.

It is best to remove the build plate from the printer before attempting to remove parts with a scraper or knife.

5. Use floss

Dental floss can sometimes be used to remove parts from the build surface. This method is effective because the floss is fine enough to get between the prints and the build surface but is unlikely to cause any damage to the 3D printer bed.

Stronger alternatives to dental floss include jewelry wire and soldering wire.

6. Use water

Water can be used in various ways to facilitate print removal from the build plate, particularly when using a glass surface.

One option is to use cold water to create a rapid temperature difference. Remove the build plate from the printer, flip it upside down, and run cold water on its underside to quickly reduce its temperature. When the build plate is cool to the touch, flip it back the right way up and try removing the parts.

If you used glue stick on top of the build surface, you can help loosen it up with warm water. In this case, run the warm water directly onto the joint between the parts and the build surface. After about a minute of water application, try removing the parts.

If you used PVA glue and the parts cannot be removed with any of the above methods, try submerging the entire build plate and parts in a sinkful of warm water for several minutes, then try removing the parts again.

7. Use chemicals

If none of the above methods work, you can try using a solvent like isopropyl alcohol (IPA) or acetone, which is particularly effective for ABS parts. The use of chemicals is best employed as a last resort, as solvents can eat away at your prints and your build surface.

To use a solvent, apply a small amount to the base of the prints with a rag, then try to remove the parts with a scraper.

Key takeaways

Getting the hang of part removal takes some time. And since it depends on your combination of printer, build plate, build surface, and other factors, it’s not always clear what advice you should follow.

While glass build plates are dependable and can provide excellent bed adhesion, beginners struggling with part removal should definitely consider investing in a flexible plate with a PEI or BuildTak surface, as this makes part removal much easier, rarely requiring much more than a quick bend of the build plate.

If a flexible build plate isn’t an option, or if parts are still regularly getting stuck to the surface, then printer users should go about part removal in a methodical manner. The sensible course of action is to attempt the simplest methods of part removal first (using hands, a scraper, or a cooling agent) before moving on to more laborious methods if that doesn’t work (warm water immersion, solvents).

Perhaps the most important thing to remember is that, even though stuck parts can be frustrating, you should always exercise caution to avoid damaging the build plate or other parts of your printer. In other words, don’t aggressively scratch up your glass bed with a knife or pour large amounts of harsh chemicals on your PEI surface just because part removal is taking longer than you expected.

By closely following this guide on how to remove 3D prints from beds, you should be able to easily remove your parts without damaging either the parts or your printer.

References

[1] Nazan MA, Ramli FR, Alkahari MR, Abdullah MA, Sudin MN. An exploration of polymer adhesion on 3D printer bed. InIOP Conference Series: Materials Science and Engineering 2017 Jun 1 (Vol. 210, No. 1, p. 012062). IOP Publishing.