Navigator #8, February 2001

Cast Urethane Used for Custom Shoe Soles
7’8” Man Finally Gets Shoes That Fit

The average male wears a size 9-C shoe. Igor Ladan an 18-year-old Russian immigrant wears an astonishing size 25-EEEEEEEEEE. Thanks to custom production soles of cast urethane made by Vista Technologies and the Redwing Shoe Company, Igor can finally enjoy a long walk in comfortable shoes.

The cast urethane soles were created based on designs by the Redwing Shoe Company, based in Redwing Minnesota. Redwing Shoe volunteered its services to make a few pairs of shoes for Igor to make his life a bit more comfortable. Jeff Jablonsky, project leader at Redwing Shoe, asked us if we could donate our services to make the pattern for the cast urethane sole. Creating the sole pattern and mold could be one of the most expensive parts of the shoe. We looked forward to the challenge.

Dirk Cornelius at Redwing Shoe designed a 3D CAD model of the sole using Alias and Pro-E. Based on his data, we made an SLA pattern of both the left and right sole. Each sole ran on one SLA 5000 for over 70 hours. After the SLA master patterns were cured and finished, Joe Roth, president of Precision Models, added texture to the soles to prepare the pattern for the next step. The textured SLA patterns were then sent to Redwing Shoe, where they were used to create an epoxy tool.


Igor 7'8" & Jason Lilla 5'10" stand next to an 8 foot tree holding the SLA patterns.

Redwing Shoe cast urethane into the epoxy tool. When the soles were pulled from the mold, they were to size, with texture and ready for fitting. On December 27, 2000, Redwing hosted an open house for the vendors who helped with this project so everyone involved could meet Igor.

Dan Mishek and Jason Lilla of Vista Technologies attended the open house to meet Igor. Lilla said, “Igor was a wonderful person with a great sense of humor. He seemed to be very excited about his new shoes. He mentioned they were in his favorite color.”

Igor now resides in Rochester and is attending a local community college. We thank Redwing Shoe Company for including us in such a great project, and we wish Igor the best of luck and health.


Vista's sales manager's son, Colt, enjoys his new crib for the time being. (Igor's shoe)

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Do You Know SLA?
Stereolithography Apparatus

This has become a cornerstone for the rapid prototyping industry. SLA has been around for over ten years, now. Everybody knows about SLA, but does everyone know SLA?

Did you know that the largest platform size is 20 x 20 x 23 inches? Parts larger than platform size can be bonded using the same material for a seamless and strong bond. SLA's can be used not only to check fit and form, but for visual content, also. SLA's can be primed and painted to match any Pantone color or PMS number with texture for photo-shoots, tradeshows, or marketing meetings.

SLA's can also be color tinted in a transparent look for last minute meetings. For other surface finishes, SLA is not limited. SLA's can be chrome plated, vacuum plated, or plated with nickel, zinc, or copper. Customized texture can be added to imitate leather, wood grain, or an EDM finish.

SLA properties have changed.Now there are options depending on the application. The options in resin are the standard, flexible, water deterrent, or high temperature resin (up to 400 degree F.)

For more functional uses on an SLA, they can be machined, drilled, tapped, and inserts can be added. Standard SLA material impellers, under the right circumstances, have been tested to run at 15,000 RPMąs.

SLA's are also used daily as master patterns for more functional prototypes. SLA patterns are supplied for RTV (room temperature vulcanizing) molding to create parts from cast urethane. SLA patterns are also used in creating epoxy tooling for injection molded plastic or injected wax.

For metals, SLA's are used as patterns in RPM (rubber plaster molding) to produce nonferrous metals such as aluminum or zinc. Also, a shelled out SLA (with an inner honeycomb pattern) is called a Quickcast® SLA.

These are used as patterns for investment casting (or the loss wax method). Plain SLA patterns can also be used in sand casting and in vacuum forming.

SLA cores and cavities have even been used in plastic injection molding and blow molding. This is called Direct Aim or Bridge Tooling.

All these applications can only be touched on briefly in one article. Please contact your sales representative to see and understand how SLA can help in your rapid prototyping applications.

Quick Quip "Every job is a self-portrait of the person who did it."