TMC Lightweight Optical Breadboard 75 Series

• 75 Lightweight Series
  Minimizes both weight and cost. These breadboards have relatively high levels of rigidity, as they utilize our standard steel core, however, with their thin top and bottom skins, they cannot have the rigidity and damping properties of the 78 and 77 series. They are ideal when light loads are anticipated and low weight and/or cost are the most crucial factors. The weight savings – 50% less than the 78 Series Breadboard.

CleanTop Advantage

Our steel breadboards can be readily designed to meet custom requirements including custom mounting hole patterns, through-holes, special shapes and custom materials.

All steel construction. No particle board sidewalls or plastic layer between top skin and honeycomb core. Assures maximum strength and structural integrity

Smallest core cell size, highest core density. The CleanTop design does not require enlarging the steel honeycomb core cell size because CleanTop cups are cylindrical, not conical as found in plastic layer designs. CleanTop's average cell size of 0.5 in.(2) is at least 50% smaller than that achieved with plastic layer designs assuring the highest stiffness and greatest core-to-skin bonding contact area

Steel to steel to steel. CleanTop achieves a spill-proof core with only two bonding layers: top skin to core and core to bottom skin. Imitations must add a third bonding layer which weakens the structure: top skin to plastic layer, plastic layer to core, and core to bottom skin.

Thermal stability. The CleanTop all steel construction assures materials of identical coefficient of thermal expansion ensuring optimal thermal stability. 

TMC's CleanTop Optical Top is the best method yet for providing a spill-proof, clean, precise, and corrosion resistant optical top with unmatched structural performance. CleanTop is now a standard feature of all TMC optical tops.

Individual CleanTop cups are epoxy-bonded under each tapped hole after it is tapped and cleaned. Cups are made from chemically resistant nylon 6, and stainless steel (304 alloy) cups are available. Holes are now tapped and countersunk prior to adding the cups to allow the machined top sheet to be thoroughly cleaned with open, rather than blind, holes prior to bonding. The top plate is processed through a custom TMC industrial cleaning center where a high pressure, high temperature cleaning solution is forced through each threaded hole, completely clearing any machining or tapping debris. Several rinse and dry cycles ensure an essentially "sterilized" top surface prior to bonding the cups.

CleanTop represents another innovation in TMC's long optical top tradition of industry "firsts" including:

• First spill-proof optical top (CleanTop) 
• First all-steel optical top 
• First oil-free optical top 
• First honeycomb core registered  to the tapped hole array
• First lightweight breadboard with formed rather than drilled holes
• First vacuum compatible optical top

Features:

• Liquid spills on the surface are contained and cannot reach the top's honeycomb core.
• The core is completely clean and dry with no residual thread-cutting oils to out-gas.
• Extremely clean tapped holes make screw insertion smooth and simple.
• Easy retrieval of small parts dropped into the holes is assured.
• Since no penetration of the core is possible when dangerous chemicals are used on the top's surface, health hazards will not occur by chemicals reaching the core unnoticed. 

Specifications

• Core: Steel honeycomb, closed cell, 0.01 in. (0.2 mm) thick foil
• Core shear modulus: 275,000 PSI (19300 kg/cm2)
• Core cell size: < 0.5 in.2 (3 cm2)
• Core density: 13.3 lb/ft3 (230 kg/m3)
• Flatness: +/-0.005 in. (0.13 mm)
• Top skin: 430 series ferromagnetic stainless steel
• Top skin thickness: (2 mm) for 75 series
• Sidewalls: Damped formed steel channel covered with vinyl
• Tapped holes: Backed by 1 in. (25 mm) long CleanTop nylon cups.