Removing the Support Material

After printed models have cooled, the Support material must be removed. This can be done by different methods, depending on the type of Support material, the size of the model, how delicate it is, the amount and location of the Support material, and other factors. The methods described in this section refer to removing general-purpose Support materials from models, for most printing applications. Use this information as a guide, and adapt the methods (or a combination of them) for cleaning your models.

For special printing applications, refer to documents on the Stratasys Support Center or consult a Stratasys 3D printing expert.

There are two types of Support material available:

•

SUP705 (FullCure705), a gel-like Support material.

•

SUP707, a water-soluble support material, suitable for some printers.

Removing SUP705

SUP705 (FullCure705) Support material can be removed from printed models using the following methods, in this order:

by hand

water pressure (in a suitable cleaning unit)

1% caustic soda solution (recommended for a smooth finish)

Removing Excess Support Material by Hand

While wearing protective gloves, break away excess Support material on the outside of the model. For delicate models, use a toothpick, pin or small brush after dipping the model in water.

Removing Support Material with Water Pressure

For most models, the most efficient way to remove Support material is by using a high-pressure water jet. One suitable system is the Objet WaterJet cleaning unit. This device is marketed by Stratasys.

To clean a model using this device, you manipulate it and the water using the built-in, waterproof sleeves. A pump turns ordinary tap water into a high-pressure jet. A wiper keeps the window clear.

Use caution when cleaning delicate models with high-pressure water systems.

Removing SUP705 with Caustic Soda

Soak models in a 1-percent solution of caustic soda (sodium hydroxide) to remove Support material from difficult-to-reach areas and to give the model a smooth, clean finish. The amount of time you soak the model in the solution depends on how delicate it is and how much Support material needs to be removed, but it is typically between half-an-hour and several hours. In any case, you should remove as much Support material as possible before the caustic soda treatment, and rinse the model thoroughly (with a water jet) afterwards.

Caustic soda may cause chemical burns, scarring and blindness. Mixing it with water generates heat that could ignite other materials. Never pour water into caustic soda. When diluting the solution, always add caustic soda to water. Take adequate safety precautions; always use nitrile gloves when handling caustic soda and models soaked in it.

Removing SUP707

SUP707 (water-soluble support material) can be removed from printed models using the following methods, in this order:

water-whirlpool treatment (in a suitable cleaning unit)

1% caustic soda solution (recommended to remove traces of support material)

15% glycerol (recommended to strengthen the walls of the model)

Removing Support Material with a Whirlpool Cleaning Unit

When printed models are placed in a whirlpool water bath, jets of water and air cause the support material to come free of the model and dissolve. One suitable cleaning system is the DT3 CleanStation.

When the cleaning cycle is complete, inspect the models. If additional treatment is necessary, replace the water in the cleaning unit and repeat the cleaning cycle.

Soaking models in Caustic Soda (Recommended)

Soak models in a 1-percent solution of caustic soda (sodium hydroxide) to remove excess support material and to give the model a smooth, clean finish. The amount of time you soak the model in the solution depends on how delicate it is and how much support material needs to be removed, but it is typically between three to eight hours. Rinse the model thoroughly after soaking.

Caustic soda may cause chemical burns, scarring and blindness. Mixing it with water generates heat that could ignite other materials. Never pour water into a caustic soda solution. When diluting the solution, always add caustic soda to water. Take adequate safety precautions; always use nitrile gloves when handling caustic soda and models soaked in it.

Strengthening Models with Glycerol

After printing with SUP707 support material and using the methods described above to remove it from printed models, it is recommended to strengthen the walls of models by immersing them in a 15‑percent glycerol solution for a few minutes.

Note: After this treatment, do not rinse the model, and allow it to dry overnight.