Castle Island's Web site
Internet Editorial

By Terry Wohlers

An edited version was published in Rapid Prototyping Journal, Vol. 7, No. 5, 2001, MCB University Press. Copyright 2001 by Terry T. Wohlers

From time to time, you discover a website that is loaded with useful information, costs nothing to use it, and is light on advertising.  Castle Island Company offers such a website (  The site includes a directory of service bureaus, an RP patents database, and a listing of RP publications.  It also includes listings of RP machine and materials manufacturers, an introduction to RP technologies, a brief tutorial on RP and rapid tooling, and a discussion on medical applications of RP.  

The website was developed and is being maintained by Ed Grenda, an electronics engineer based in Arlington, Massachusetts, USA.  Grenda founded and was CEO of Cambridge Technology, a leading manufacturer of optical scanning instrumentation.  In addition to optical components, Grenda has experience in the development of electromechanical systems such as computer peripherals, printers, optical character readers, and data collection terminals.  Today, he spends much of his time building the Castle Island website.

The service bureau listings, referred to by Grenda as the Worldwide RP Service Bureau Directory, include 540 service provider locations with descriptions.  The companies are categorized by geographic region, so it’s easy to find a company by region.  Keeping the directory up-to-date, however, looks like an almost impossible job.

It’s easy to tell that Grenda spends considerable time with his RP patent database.  As of August 2001, it included nearly 750 RP-related patents filed in the USA. Due to recent legal changes, according to Grenda, published patent applications are now also available.  The patent database includes a search engine that helps find patents by topic.

The listing of RP publications, dubbed The Mother of All RP Bibliographies, includes nearly 3,400 references.  Grenda says that it is the largest source of technical information on RP in the world.  Its search engine did not find any matches when I entered “market trends” which I found a little odd.  Also, it did not find a listing for an established RP publication, so it may exclude others too.  Recent additions to the database include abstracts of dissertations and reports from Clemson University's Laboratory to Advance Industrial Prototyping. 

The website can be a little difficult to navigate and it could include more pictures and graphics to help offset the paragraphs of text that might overwhelm some visitors.  Overall, however, Grenda did a fine job pulling together the information and making it available at the website.  He is a good researcher and an excellent writer and I recommend the site to anyone interested in the subject of rapid prototyping.