FabPro JewelCast GRN

A green material ideal for small, fine featured jewelry master patterns for gypsum investment casting applications. This material leaves minimal ash after burnout to produce superior casting quality. Create and produce custom jewelry or other investment castings that capture fine detail with a smooth surface finish.

Part Quality and Accuracy Tips

In order to achieve good accuracy with JewelCast-GRN, it is important to follow the part setup instructions below for orientation and supports. Some other key tips are as follows:

  1. Follow and apply accuracy wizard procedure for each printer to get highest accuracy parts.
  2. Manually check support location before printing.
  3. In thicker cross sections for large rings or non-ring geometries, go up in cure depth to avoid delamination between layers. Go up in 10µm increments to prevent over curing features.
  4. For parts thicker than 3.5mm use Heavy Mode to print the ring. If any cracking is seen after printing in Heavy Mode, raise the cure depth by 10µm.
  5. If positive features have poor resolution, the Border Thickness parameter in the build style could be increased up to 20%. It is not suggested to go higher or negative features might get closed or too small.
  6. If detail is blurry, check for proper cleaning method. Insure cleaning solvents are not saturated and parts are allowed to dry before post cure.
  7. If detailing is still blurred, lower cure depth in 10µm increments.
  8. If detail remains an issue or accuracy is hard to achieve run the accuracy wizard for this build style.
  9. Verify proper cleaning method. Insure cleaning solvents are not saturated and parts are allowed to dry before post cure.
  10. Make sure all IPA has been evaporated off, and allow for parts to dry completely. If surface finish is still shiny and not matte after cleaning, not all resin has been removed and it will show up in the casting. Repeat cleaning and drying until parts do not have any excess material.

Orientation

The orientation for thick parts is best when oriented vertically to minimize supports.

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Figure 1. Ring print orientation in 3DSprint

 

Add Supports – Full Arches

Add supports to the part using the Create Supports function under the Smart Supports icon. Look at the supports and determine how they may need to be modified.

Jewelry parts will need to be checked manually to verify supports are on the correct part of the rings to prevent damage to the part during support removal. In 3DSprint start by viewing the rings from the bottom-up.

Thin and Multiple band Ring Geometry

Rings with thin bands and multiple-band geometry need to be properly supported to maintain roundness of all bands.

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Figure 2. Ring view from bottom-up.

 

Go to the Analyze tab in the Smart Supports and Update Placement to view the default supports. Many of these supports will need to be removed.

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Figure 3. Default support placement.

 

After loading the default supports go to the Manual Tab to remove supports. Remove the supports that are on the crown. Note also that this part of the ring is mostly self-supporting. The reason the software adds these supports is that the default supports must cover all general parts. Thus, the support coverage will be conservative for reliability.

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Figure 4. Manually edited support removal result.

 

Use the Clipping function in the View window to scroll thru the part to see if any anchor points are on the inside that need to be removed.

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Figure 5. This ring has many anchor points that need to be removed from the inside of the part.

 

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Figure 6. This ring has the anchor points removed from the inside of the part.

 

Next, be sure to remove anchor points from features that can be self-supporting.

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Figure 7. The ring on the right has the feature anchor point removed.

 

The band and underside of the crown are the ideal places to support. This is because support removal is easy and less likely to scar the part in these areas. Support the extra bands with more anchor points at the starting area of the ring.

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Figure 8. Anchor points added to starting point 2nd and 3rd bands of the ring.

 

To maintain roundness of the part during printing, add anchor points at intervals going up the ring sides. Ensure all bands of the ring are supported.

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Figure 9. Anchor points added to starting point 2nd and 3rd bands of the ring.

 

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Figure 10. Ring with final support solution.

 

The tips can be made smaller if desired by using  The Pillar Top Ratio parameter in the Tip section.

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Figure 11.The Pillar Top Ratio parameter is highlighted with a star.

 

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Figure 12. Note the support tip change by making the Pillar Top Ratio 0.3 rather than 0.15.

 

Wide Band Ring Geometry

Rings with wide bands require more anchor points on the bottom half of the ring band. This will help maintain the roundness of the ring and control the shape of the bottom of the ring to minimize post processing.

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Figure 13. Wide band ring.

 

The default anchor points on the ring band will not be enough to maintain the shape.

NOTE: Because the manual support editing is necessary, the 3DSprint software defaults to less supports so removing supports and adding supports is easier for the user.

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Figure 14. Default anchor points on thick ring band.

 

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Figure 15. Modified anchor points on thick ring band.