3M VHB Transparent and Grey Tapes

Key Features

• Clear, double-sided, solid acrylic foam tape.
• Total tape thickness: 0.020 inch (0.5 mm, or 20 mil) for the 4905 variant.
• General-purpose acrylic adhesive on both sides; bonds well to high surface energy (HSE) substrates like aluminum, stainless steel, glass.
• Designed for clear or colorless applications (transparent or translucent materials).
• Excellent for replacing rivets, welds, screws, or liquid adhesives; immediate handling strength, no cure time.
• Long-term durability: withstands indoor/outdoor use; rated for long-term up to ~200 °F (93 °C), short-term up to ~300 °F (149 °C).
• Also provides sealing, vibration/noise damping, moisture/UV/solvent resistance.

Typical Applications

• Bonding transparent materials, e.g., back-lit translucent signs, resin-filled glass, edge bonding of glass.
• Joining metal, glass, high surface energy plastics (e.g., polycarbonate, acrylic).
• Where invisible or minimally visible bonding is desired (since tape is clear).
• Replacing mechanical fasteners in thin/dissimilar material constructions.

Important Specs & Details

• Foam core: closed-cell acrylic foam.
• Liner: Red printed PE film.
• Density: ~960 kg/m³ (60 lb/ft³) typical for the foam.
• Application temperature: can go down to –40 °F and up to +200 °F continuous in some sources.

Summary

If you have a design involving transparent or translucent materials and want a very high bond that remains nearly invisible, the 4905 is a strong option — moderate thickness (0.5 mm) gives a relatively low profile.

3M VHB Tape 4910

Key Features

• Also a clear, double-sided acrylic foam tape, part of the 4910 family (which the 4905 is also part of).
• Total tape thickness: 0.040 inch (1.0 mm, or 40 mil) for the 4910.
• Same general-purpose clear acrylic adhesive; designed for high surface energy substrates and transparent applications.
• Immediate handling strength, similar durability features (resists UV, moisture, can be used outdoors) and can replace rivets/screws/welds.

Typical Applications

• Situations where a thicker foam core is preferred (perhaps more gap filling, more flexibility, more conformability) while still maintaining transparency.
• Bonding panels, frames, signage, glass, acrylic, or other decorative/architectural uses.
• Because of the 1.0 mm thickness, perhaps better for applications with more surface irregularity or needing more “cushion” or alignment tolerance.

Important Specs & Details

• Foam core: firm acrylic foam.
• Same liner (red PE film) and adhesive type.
• Thickness tolerance: ±10% for 4910.
• Similar service temperature ranges as 4905: –40 °F to ~200 °F for continuous use in some spec sheets.

Summary

If you need the same clear/transparent bonding but your design has slightly larger gaps, irregularities, or needs a thicker profile (for example to accommodate thicker panels or surfaces that are not perfectly flat), the 4910 gives that extra thickness while maintaining the high bond and transparent look.

3. Comparison & Selection Considerations

Here’s a quick comparison and tips when deciding between these two (or more broadly within the VHB family):

Key Considerations

When choosing between grey vs clear VHB:

• Is transparency/appearance important? If yes (you want minimal visible bond line or bonding transparent/clear materials), then a clear VHB (like 4905, 4910) is preferable.
• Surface condition & substrate type: If the surfaces are painted, powder-coated, textured, or involve dissimilar materials, a grey version (with more forgiving foam or adhesive) may perform better.
• Gap/foil fill / panel-to-frame applications: If the application involves bigger gaps, thicker panels, exterior durability (e.g., façade, commercial vehicle panels), grey thicker foam VHB may be more appropriate.
• Aesthetics vs performance trade-off: Clear tapes are better for aesthetics/invisible bonding; grey tapes may sacrifice some aesthetics but gain functional robustness.

Summary recommendation

• If your priority is invisible bonding, bonding transparent or clear materials, smooth flat surfaces, and aesthetics: go with a clear VHB (e.g., Tape 4905 or 4910).
• If your priority is structural bond (panel-to-frame, uneven surfaces, painted/powder-coated surfaces, outdoors, larger gaps): pick a grey version (like 4941, 4611, RP+ series).
• Always check the specific datasheet for the exact variant: thickness, foam core characteristics, liner type, substrate compatibility.