An
effective table top design must incorporate
three critical factors: mass, stiffness
and damping.
Mass ensures that forces applied to the
table top will cause minimal displacements. Stiffness raises the
table tops lowest resonance
out of the working range and provides a
more stable work surface. Damping decays the higher frequency vibration
that reaches the top.
TMC provides three basic versions of table tops: stainless steel laminate, CleanTop® II steel honeycomb, and granite.
Stainless Steel Laminate
The standard TMC top plate is a 2 to 4 in.
thick, highly damped, high stiffness lamination
of steel plates sandwiched around a lightweight
damped core, rigid epoxy-bonded into a
seamless stainless steel pan with rounded
edges and corners. With their combinations
of structural epoxies and visco-elastic
adhesives, these tops will not delaminate
due to heat, humidity, or aging. TMC laminated tops are recommended
for most applications not requiring mounting holes.
Laminated tops are standard on 64 Series TableTop™ Platforms, 65 Series Floor Platforms, and 63-500 and 68-500 Series Lab Tables, and 63-600 ClassOne™ Workstations, and Quiet Island Floor Platforms. They can also be supplied with a plastic top skin laminated onto the stainless steel to make an even more easily cleanable surface. Plastic skins do, however, detract from the ferromagnetic properties of the top and are unsatisfactory for magnetic hold- downs.
Steel Honeycomb CleanTop®
Increasingly, researchers are using honeycomb
construction tops with their lab tables to facilitate bolt-down
mounting of their equipment to a flat and stable work surface.
TMC's spill-proof CleanTop® II is uniquely suited
to such applications.
For a complete discussion of CleanTop ® Optical Tops, see our Optical Tops Section.
Granite Tops
Granite surfaces are standard with 64
Series tabletop platforms. They are available on special order
with other isolation systems. The advantages of a granite top are
its relatively high mass and stiffness and the potential for being
lapped to a precise surface flatness. Granite's non-magnetic nature
is useful in some applications.
For small tops, granite is an inexpensive,
moderate performance material. In larger sizes, however, granite
is more expensive than standard TMC top plates, sacrifices damping,
and does not have other desirable features.
