Madeinusa

POLYJET PROTOTYPES

Ability to create prototypes utilizing multiple materials.

ABOUT POLYJET PROTOTYPES

Polyjet™ 3D printing works by depositing multiple drops of photopolymer resin on the build platform and immediately passing a UV light source over the layer which cures the resin.  This cures the layer.  The platform lowers by one layer, and the next layer is deposited onto the previous layer.

The advantage of Polyjet™ technology is the ability to incorporate multiple materials into a prototype simultaneously such as rubber-like material over or next to polypropylene-like material.

Our Polyjet Process

Our in-house Polyjet™ prototyping facilities provide prototype parts quickly and cost effectively with the highest build quality standards.

Utilizing Stratasys Connex™ technology allows us to print multi material parts quickly and cost effectively.

Our staff has decades of experience not only in prototyping but also in product manufacturing.

We offer a range of build resolutions, materials and finishing options.  We are happy to discuss any special needs or requests.

PolyJet Prototype Specification Guidelines

Outlined below are the options which need to be specified when ordering a PolyJet prototype. This includes materials, resolutions, and finishing.

Rigur RGD450

Rigur is a rigid, off-white model material that simulates polypropylene in appearance and functionality. It offers excellent durability and dimensional stability. Rigur is ideal for flexible closures, reusable containers, packaging, and white appliances including consumer goods, household appliances, consumer electronics and automotive parts.

TangoBlackPlus FLX980

Tango is a flexible photopolymer that simulates soft-touch coating, nonslip surfaces, rubber surrounds or over-molding.

FLX4840-DM

A rubber-like digital material with a Shore A hardness of 35-40.

FLX4850-DM

A rubber-like digital material with a Shore A hardness of 45-50.

FLX4860-DM

A rubber-like digital material with a Shore A hardness of 57-63.

FLX4870-DM

A rubber-like digital material with a Shore A hardness of 68-72.

FLX4885-DM

A rubber-like digital material with a Shore A hardness of 80-85.

FLX4895-DM

A rubber-like digital material with a Shore A hardness of 92-95.

Material Selection Options

Photocurable Resin

General Resolution Info:

The printing resolution is 600 x 600 dpi in both the X and Y Axes.
The accuracy is 0.1 - 0.3 mm (.004 - 0.01 inch) typical. The accuracy varies according to geometry, part orientation and print size.

Standard Resolution

Layer thickness of 16 micron (0.0006" layers).

Low Resolution

Layer thickness of 30 micron (0.001" layers).

Build Resolution Options

Basic Finish

Part is cleaned. All support material is removed

Standard Finish

Basic finish + Part is sanded to remove the heaviest of the stair stepping (build lines) on the exterior or outside of the part.

Finishing Options

PolyJet Design Considerations

You can design for the PolyJet process, however, it is more advantageous to design for the manufacturing process you will ultimately be using. Then make any small changles needed for the PolyJet process, in any.

Designed parts should have a minimum wall thickness of 0.025″ or 0.6 mm.  If the wall is load bearing or part of a structure, the wall thickness should not be less than 0.40″ or 1 mm.

Adding fillets, where two different sections of the geometry meet, provides additional reinforcement and stress relief.

Placing a larger fillet radius on internal surfaces, increases strength and decreases the effect of thin walled sections with fillets acting as a spring.

For embossed and engraved details follow these recommendations:

  • A minimum line thickness of 0.5 mm.
  • A depth of 0.5 mm is optimum.
  • A raised height of 0.2 mm above the surface of the model.
  • Font selection is important.  A bold sans serif, such as Arial boad / rounded is ideal.

Follow these recommendations and considerations to print screws and threads.

  • When printing very small threads that will be subjected to regular operation, the threaded section may become stripped over time.  Off-the-shelf hardware will be more durable.
  • When printing threads:
    • It is not recommended to print threads below M5.  Although they are printable, they are unlikely to hold up to any torque without the thread stripping.
    • An ACME or BUTTRESS type screw-thread should be used.  For best results, ensure an offset clearance betweein mating part of 0.15 – 0.2 between the male and female threaded section.

Follow these recommendations and considerations to incorporate off-the-shelf hardware into a printed part.

  • For screws that will be subjected to regular use, print a socket or a pocket for the nut (with a 0.1 mm offset) that can be press fitted into position.  If the screw or bolt will be subjected to frequent extraction and re-insertion, then glue it in place.
  • Design a cylinder, which will be manually tapped after printing.  Alternately, design a rough thread to be printed, and then manually tapped to clean up the channel.
  • Avoid using self-tapping screws (for plastic) for applications that require frequent assembly or disassembly, as the threads may shear and the bosses may crack.
  • Use press fit or heat-set inserts.
    • When designing for heat-set inserts, design extra space/tolerance around the diameter of the insert so that the adhesive can bond effectively.
    • The knurled textured outer surface on heat-set inserts make them very effective for providing plenty of surface area for adhesive.
    • Use either a 2-part epoxy for Cyanoacrylate (CA) glue.
    • Make sure that adhesive is not applied on the internal thread.
    • Make sure that the adhesive has fully cured before inserting screw.
    • Add textured geometery to the inside of the insert housing to provide greater surface for the adhesive.
    • If possible, design the insert so that it is inserted from underside of the part and the bolt pulls against the shoulder of the pocket for extra strength.
  • Use an expanding threaded insert.

Snap-fit tabs are used in many applications, form enclosures to clasps, and are used in product assembly to make the use of screws and additional processes redundant.

  • Snap fits can be design to be lock and inseparable, or in a way that enables frequent operations with a secure fit in the engaged position.
  • A simple cantilever style snap fit is the most effective.
  • Long snap-fit tabs should be slightly tapered towards the tip for an even distribution of stress.
  • For longevity, the tab should be created with fillets at the base.
  • The fillet radius should be at least 0.5  the thickness of the cantilever.
  • To remove some of the shear stresses from the snap fit, add location geometry guides to other parts of the model.
  • A tolerance/clearance of 0.3 mm between parts is recommended.

Other types of snaps that are easily printable can be used, including snap pins.

  • Design snap pins with the same considerations as snap-fit tabs.
  • For firmer, more positive snaps, the taper can be removed.

POLYJET Prototype Quote Submission

You will receive an e-mail confirming receipt of your request.

Files up to 20MB may be sent via e-mail to:  Sales@Versadyne.net