Dream specializes in the use of Carbon
Fiber skinned, thick-walled Sandwich Core
technology (CFSC). Dream's specific CFSC matrix offers our clients
the highest stiffness to weight
ratio, helping to maintain optical alignment and focus all-sky
and over very broad temperature ranges. |
They
are specifically designed to closely match the CTE of borosilicate
glass. |
We have over 10 years of empirical data
showing our telescopes can maintain focus and optical alignment,
all-sky, over 20°F temperature changes using the
following system: |
- f3.75: Depth Of Focus
is 31 microns. (DOF of f10 = 220 microns. Can absorb
much larger focus shifts.) |
- 52mm image circles: 37mm x 37mm detectors.
The larger the focal plane, the more sensitive the system. |
- Telescope tubes 3x longer than compact
SCT's. Focus shifts are based on length and CTE. |
|
Dream's CFSC tubes do NOT require something else to be bolted
to them in order to achieve their incredibly high stiffness.
They can be attached to a mount on one side of the tube. What's
the point of investing in a carbon fiber tube if it requires
other supports to achieve a stiffness that can't compare to Dream's
CFSC tubes? What happens when this 1.85 pound
Dream CFSC strut is replaced with a solid laminate (no
core) strut of the same mass? Answer; the floor... |
|
All of Dream's advanced
composite parts are designed & fabricated in-house using
high performance, high temperature epoxy, vacuum bagged
and cooked in one of our ovens. A black-surfaced material
in the Sun on a day when it is only 70°F will go to over
160°F. |
Dream uses vacuum bagging because it is 20-40+ times more force
than compression-wrapping. Vacuum bagging is far more uniform
as well. In composites we need to force out air, moisture and
excess resin in order to reduce voids and to get the fibers closer
together. Performance is in the fibers, not in the heavy resin.
We've seen what very low vacuum does to the parts. It's a night
and day difference in performance. |
What happens to layers and layers of carbon
fiber that are progressively added to the outside of a male mandrel,
then lightly compressed inward? They form wrinkles. The greater
the number of layers added, the bigger the problem. Small-scale
wrinkles are the Achilles heel of composites. It is to be avoided
at all costs. Dream's tubes are fabricated using a method that
tensions the carbon fibers. |