Below are some of the most frequently asked questions that we have heard and answered since Dream's inception in 2003.

1. Q: Are all carbon fiber parts brittle and therefore extremely fragile? 
....A: This is a common misconception. Dream's properly made carbon fiber parts are not fragile. Please see the videos on this page as a vivid illustration of just how rugged Dream's advanced composite parts are. Also keep in mind that Dream's composites are inherently resistent to moisture/humidity, are non-corrosive, have a low CTE, low thermal fatigue and are quite chemically resistent. Because we cook each part in one of our ovens, the parts are also stable at higher temperatures.

2. Q: Do all carbon fiber parts vary in mechanical performance from part to part, making them impossible to use in high-performance opto-mechanical systems?
....A: Most of the time this comment is coming from companies or individuals that have little to no knowledge of advanced composites. Or they have tried Dream started as an advanced composites company solely for the purpose of making structures for opto-mechanical systems, which require high-stiffness, not strength, and low CTE. Dream isn't a standard "composites shop" that makes fiberglass boats or car bumpers. Such shops lack an understanding of the extremely tight tolerances that are required for opto-mechanical systems. We are the only company in the world that has a deep understanding of optics and a deep understanding of composites. Dream understsands composite materials & methods as they relate to stiffness and CTE. We have tight process controls, like our +/-1°F largest composites oven. Bringing all of this together has allowed us to focus on methods that are highly consistent from part to part.

3. Q: Do all carbon fiber parts vary in Coefficient of Thermal Expansion (CTE) from part to part, making them impossible to use in high-performance opto-mechanical systems?
....A: As stated above Dream has always had optical systems in mind for the composties. We are not a general composites company that is trying to shoehorn our composites into precision optical systems. Dream was formed specifically for the opto-mechanical industry. We can produce a part today, then again two years from now with extreme consistency in the part, both mechanical performance (question 2. above) and CTE (question 4. below). They typically coincide with each other (mechanical and thermal), although mechanical properties and thermal properties are two completely different attributes of a part.

4. Q: Do all composite parts have resin-rich areas that will have a wildly different CTE than other areas, therefore causing the part to distort?

....A: From day one Dream has always; paid especially close attention to fiber orientation & resin content, used high-temperature epoxy that is specifically engineered for an optimal match to our mirrors, used vacuum bagging and high temperature baking of the parts to provide the utmost in consistency and part performance. Wildly varying performance is common in wet layup parts that do not use vacuum bagging. Overwrapping the parts with weak plastic, similar to Saran Wrap, will have almost no force on the part and therefore are not consolidating the layers of CF. Part thickness can easily be double when full vacuum bagging is not used. If carbon fiber parts that you have received from others make cracking sounds when you squeeze them tightly, they are inferior parts. Those are void areas collapsing and are a red flag that the piece is not a high performance part.

Full vacuum is applying roughly one ton of force on the part per square foot. A part with six square feet of surface area has roughly six tons of force applied across the part. Unlike a press, that inherently will have "hot spots" (higher pressure and subsequent lower pressures), properly executed vacuum bagging will produce the same pressure across the entire part, regardless of it's shape. It is technically impossible for Dream's advanced composite parts to have wildly different CTE, because of our extensive exerpience, focus on making consistent parts and proven methods that we use.

Contact Dream today to discuss your project with our experts.

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