Thermo101 Impossibleratio

. Thermoforming 101 The Impossible Draw Ratio A Technical Article – 2006 Volume 26, #3 . By Barry Shepherd (Technical Editor’s Note: Looking back over the last 9 years at 36 Thermoforming 101 articles, which are all presented in our annually updated booklet, it is the most comprehensive collection of basic technical information one could … Continued

Thermo101 Reality

A TECHNICAL ARTICLE 2005 VOLUME 24, #2 Comparing Concept to Reality1 We began our discussion of part design by reviewing why we might not want to quote on a job. If we are serious about fabricating the customer’s concept, we need to understand the methodology in reducing a concept to reality. Naiveté v. Experience Before … Continued

Thermo101 Recyrstal

A TECHNICAL ARTICLE 2004 VOLUME 23, #1 Recrystallization – What Does That Mean?1 In the last TF101, I mentioned recrys- tallization. In this tutorial, I will explain what it is and why it is important in thermoforming. Amorphous and Crystalline Plastics – A Brief Review In a very early lesson, we learned that there are … Continued

Thermo101 Stretch

A TECHNICAL ARTICLE 2005 VOLUME 24, #3 Understanding How a Sheet Stretches1 We began our discussion of part design by reviewing why we might not want to quote on a job. But let’s suppose that we did quote on the job. And we got it. Now what? Forming into a Mold v. Forming onto a … Continued

Thermo101 Downgauging

A TECHNICAL ARTICLE 2007 VOLUME 26, #2 “Down Gauging” – It’s a Good Thing How many of us quote jobs and specify the starting gauge? I would suggest that the majority of custom thermoformers are accustomed to quoting this way. In the case of proprietary thermoformers producing such things as food service items, although the … Continued

Thermo101 Draftangles

A TECHNICAL ARTICLE 2006 VOLUME 25, #1 Draft Angles Some time ago, we discussed shrinkage and warpage. At that time, we pointed out that plastic, like most other materials, increases in volume when heated and decreases in volume when cooled. And we said that to form the desired shape, the hot plastic is pushed against … Continued

Thermo101 Drawratio

A TECHNICAL ARTICLE 2005 VOLUME 24, #4 The Ubiquitous1 Draw Ratio Probably the first thing a novice hears in thermo- forming after he/she learns to spell “thermoforming,” is the phrase, “Draw Ratio.” So, this lesson focuses on the concept of draw ratio. Is There More Than One Definition? Unfortunately, yes. There are at least three … Continued

Thermo101 Cycletime

A TECHNICAL ARTICLE 2007 VOLUME 26, #1 Process – Cycle Time (Editor’s Note: This is the first Thermoforming 101 article written by your new technical editor. Dr. Throne wrote 34 articles that date back to 1998, Volume 17, Number 3. He had originally intended to write a series of 18 general interest articles but the … Continued

Thermo101 Design

A TECHNICAL ARTICLE 2005 VOLUME 24, #1 Why is Part Design Important? Throughout this series of tutorials, we have assiduously1 avoided the issue of part design. And for good reasons. First and foremost, technologists – of which I am one – are normally not good designers. We tend to get hung up on the nuts- … Continued

Thermo101 Corners

A TECHNICAL ARTICLE 2006 VOLUME 25, #2 CORNERS Most plastic parts have corners. And most corners are radiused. Designers often seek sharp corners or more properly, corners with very small radii. Aesthetics is often cited as the reason for this. But aesthetics is not the only reason. Often the container must contain material of a … Continued