Thursday Tech Tip: SUP705 Best Practices
Today, we'll be discuissing Polyjet support removal with Applications Specialist Ronald S. Stratasys has two great options for support materials; SUP705 (a non-soluble support) and SUP706 (a soluble support). SUP705 is the support material utilized by all Polyjet Desktop 3D Printers, and can also be utilized with the Objet Connex and J750 3D Printers. Effective support removal is one of the key pillars of overall Polyjet part quality, and can make the difference between good and great results. This Thursday, we'll be walking you through some tips and tricks for effective removal of SUP705.
Before printing, we must select the support style that we wish to utilize: Matte Mode, which coats the part entirely in support material, providing us with uniform surface finish, or Glossy Mode, which builds support structure only where required for the model. From a support removal perspective, parts produced in glossy mode typically provide much faster support removal than their matte counterparts. We also have the option of choosing from light, normal, or heavy support style. Choosing between the three adjusts the amount of model material interspersed in the support material, to optimize the resulting stiffness of the support structure. Again, from a removal perspective, light supports require the least effort, whilst heavy will take the most time.
After printing has completed, it is good practice to inspect your part for any defects or errors. Any defects should be noted, and if serious, sent along to our Applications Group to ensure your printer is working optimally. At the same time you can also remove large chunks of support structure manually, saving time in the WaterJet and minimizing cleanup afterwards. This also helps gauge the stress you can apply to the support removal process, something more difficult when spraying the part with water. From experience, we find that basic clay sculpting tools provide the accuracy and durability needed for easy support removal. Although some uses may employ powered tools, we prefer the manual process as it ensures part quality and integrity.
After examining the location of the support material, and removing any bulky supports by hand, it is now time for the WaterJet. This apparatus allows us to efficiently clear the support material attached to the model. We highly recommend investing in a WaterJet, as it reduces the time and effort for support removal, especially for parts with internal cavities where hand tools are unable to reach. The waterjet system is capable of two spraying mechanisms:
- Wide Set Spray: great for removing support material off of flat surfaces and in large quantities; this nozzle can cut through the support and lift off large chunks.
- Concentrated Point Spray: this nozzle increases the force and minimizes the area of contact; we'll use this option for clearing out support from cavities, or to create a 'pilot hole' through a support structure - we most often use this nozzle for cleaning vascular structures and internal channels.
CimTip: Rubbing the part with a large-area, soft-bristled brush will expedite the process and minimize the amount of WaterJetting required. We find that a soft wire brush works best. Be careful to ensure that you are not scratching the part during this process - typically darker colorurs will show scratches more easily, whereas white parts hide any imperfections well. If you wish, the part can be wet-sanded with fine grit sandpaper to make the part appear uniform if it has been scratched.
After running the part though the waterjet as much as you can, take the part out and let it dry for about 5 minutes. This will allow you to see if any leftover support material is visible. Then scrape the surface with a tool or fignernail to ensure there is not any excess supports. As you gently scrape your part, the clear indication that there is additional support is visible white material flaking off of the model surface. If this occurs, put the part back in the waterjet and repeat until no support remains. For parts printed in matte mode, this process is typically repeated at least twice.
After following the above steps, you should be left with a support-free part that looks and feels like the intended product. Remember, being thorough does take time, and it is ultimately the needs of you and your team that will dictate the appropriate amount of time to allocat to this process. Hopefully this guide has provided you with a bit of insight into our process. As always, stay tuned for future tips and tricks from our team, and please feel free to reach out with any inquiries you may have.