Why Can't You Print a Model by 3D Printer Without a Support Link?

In the use of 3D printer printing model, certainly can not be separated from the support of this link, if there is no support, those overhanging or tilted model will not be printed, so on this is also unavoidable trouble link, the next to speak in detail about this support.

1. When do I need a support structure?

When the model has an overhang or cross-bridge structure and there is nothing underneath to hold it up, you need to use a support structure. Not all overhangs need supports. If an overhang is tilted at a vertical angle of less than 45 degrees, then it can be printed without support. The horizontal offset of the 3D printer moving between the connected layers is very small (almost insignificant). Thus, instead of one layer being completely superimposed on top of the previous one, one layer is superimposed on a smaller offset. This drives the printer to print overhangs that are not too vertically inclined. All overhangs less than 45 degrees can be held up by the previous layer. 45 degrees is generally considered the critical angle. If the vertical is less than 45 degrees, no support is needed. But conditions vary from person to person, and much depends on your printer, including the performance of the printer and the materials you are using. A poorly performing printer may not be able to print a 35 or 40 degree vertical overhang!

2. Defects in 3D printed support structures

If you are using 3D printing in production, then you will care about the cost of each model. If you are a hobbyist on a tight budget, you may also be concerned about this issue. 3D printed support structures obviously increase the cost of the model. Support structures are material intensive, and some of this material is then removed and discarded. So every time a support structure is added to a 3D print, it is adding to the cost of the model. The support structure also increases the printing time. Post-processing work increases, such as removing the support. The support structure is attached to and placed on the surface of the model. If the 3D support is not removed carefully, it may leave defects on the surface of the model. In the worst case, part of the model may break off with the support structure. All in all, there are obvious drawbacks to using support structures. Therefore, use support structure as little as possible and add support only when necessary.

3. Support types

Tree support: Tree is a tree like structure used to support the overhanging part of the model. This type of 3D printing support is only connected to the overhang at some location points. The advantage of tree support is that it is easier to remove and does not destroy the overhanging bottom too much. However, it is important to note that it is only suitable for non-planar overhangs such as nose-tips, fingertips or arches. For flat overhangs, tree bracing does not provide sufficient stability.

Linear / bellows shaped support: A more common type of support in 3D printing. This type of support consists of vertical columns, and some of these columns are connected to the entire overhang. Almost every overhang and span bridge can use this type of support. But it is more difficult to remove, and then there may be damage to the surface of the model.

4. Removal of supports

First of all, observe the support structure, where it is easy to start without cover, and try to break the support with your fingers. Be as gentle as possible. If the method is correct, most of the supports should come off very easily. Use a tool to cut off some of the supports in the corners. There are many different opinions on which tool is best to use. You can use a pair of pliers, a scraper or a carving knife. Naturally there are also combinations that can be used. When using a knife or scraper, the model or blade can be moderately heated. This makes the support structure easier to remove. A small butane gun can be used, but be sure not to destroy the model. Many people do not recommend using a carving knife because it is very sharp and dangerous. Sandpaper is also a good tool.

5. Chamfering

   Another way to eliminate the support structure is to chamfer the corners. Chamfering is a clever way to turn what would otherwise be an annoying overhang into a safe overhang with an angle of less than 45 degrees. In short, many times, it is inevitable to use the support structure. However, it is also important to try to ensure the stability of the support structure without wasting too much material, easy to remove and without damaging the surface of the model.