Chem-Set VST6100C Clear Acrylic Foam High Bond Tape, 40 mil

Chem-Set VST6100C is a 40 mil clear acrylic foam tape used as a 3M VHB 4910 alternative for structural bonding of transparent and high surface energy materials. The 100% acrylic foam core carries the load while keeping the bond line clear, so it works where the joint shows through glass, acrylic (PMMA), or polycarbonate (PC). It bonds on contact and gives you handling strength immediately, with no cure time, no mixing, and no dispensing equipment.

The foam is viscoelastic, which means it stretches and relaxes instead of fighting the parts. That lets it absorb the differential expansion between dissimilar materials across a temperature swing, and it damps vibration rather than passing it into the bond line. Supplied in 1/2 in, 3/4 in, and 1 in widths on 36 yd rolls with a red PE liner. Sold by the individual roll with no case minimum, and PFAS and PFOS free per the manufacturer.

Key Product Details

Working From a 3M Part Number

If you are specced into a clear 3M VHB™ grade and need another source, use the table below to find the closest Chem-Set match. The cross reference is matched on construction, color, and thickness.

A cross reference is a starting point for selection, not a statement that two products perform the same. The specifications above are ours, published from the current manufacturer data sheet. Read both data sheets and test the tape in your own joint before you commit a production process. Call us and we’ll send a roll to test.

One limitation worth planning around. VST6100C wants the surface at 65°F or warmer when you apply it, which is warmer than some clear acrylic foam tapes call for. An unheated shop in winter is a problem for any high bond tape, and more so for this one. If you bond in cold conditions regularly, the VST 8247 and 8262 low temperature grades are built for it. Service temperature is a separate question: once the bond is properly made, the assembly holds down to -40°F.

Most shops calling us about a clear 40 mil tape are calling because of how it’s sold, not how it performs. Clear high bond grades commonly ship in case quantities from two to eighteen rolls, with lead times measured in weeks. VST6100C sells by the individual roll, with volume pricing when you need it, and in-stock orders placed by 2pm Eastern ship the same day.

How Acrylic Foam Tape Bonding Works

Acrylic foam tape does not dry or cure. It builds strength as the adhesive flows into the microscopic texture of the surface, which means the bond you get is decided almost entirely by surface prep, pressure, and dwell time. The steps below are the ones that determine whether the joint holds.

1. Get the conditions right. Bond in a dust free area. Bring the parts and the tape to at least 65°F before you apply. Cold substrate is the most common cause of a bond that feels fine on the bench and lets go a week later, because the adhesive is too firm to flow.
2. Clean the surface. Fingerprints and light oil come off with an isopropanol wipe. Heavy oil, grease, or mold release needs a degreaser or heptane solution first, then the IPA wipe. Use a lint free tissue and wipe in one direction so contamination comes off the part instead of moving around on it. Surface test inks will tell you whether the cleaner you’re using is actually working.
3. Abrade or prime when the surface calls for it. Mill finish aluminum and stainless benefit from light abrasion followed by a solvent wipe. Painted surfaces, powder coat, and medium to low surface energy plastics need a primer or activator to reach full adhesion. Apply primer only where the tape lands and wipe the excess immediately.
4. Lay the tape, then pull the liner. Apply the tape to one part first, position the assembly, then remove the red liner and mate the parts right away. Once the liner is off, the open face picks up airborne dust fast.
5. Apply real pressure. Press or roll the joint at a minimum of 15 psi across the full bond area. On a production line, roll in one direction at roughly 30 N/cm at about 24 in/min. Pressure is what pushes the adhesive into the surface. A tape that is placed but not pressed reaches a fraction of its rated strength, or none of it.
6. Let the bond build. Handling strength is immediate. Full strength develops over about 24 hours at ambient temperature, and warmth speeds it up. A primer or a short elevated temperature exposure both accelerate wet out. Plan shipping and load bearing service around that window rather than loading the joint the same hour it was made.

Joint design matters as much as prep. Design the bond so load runs in shear or tension across the full tape area. Peel and cleavage loads concentrate stress on one edge and start a failure that walks across the joint. When you need more capacity, widen the tape rather than thickening it. Thickness is for conforming to the parts, width is for carrying the load.

VST6100C is formulated for high and medium surface energy surfaces: glass, transparent plastics including acrylic and polycarbonate, stainless steel, galvanized steel, anodized aluminum, and coated aluminum.

Performance in Production

• 84 lb/in² dynamic shear means a 1 in wide strip across a 3 in bond gives roughly 250 lb of shear capacity before you apply a safety factor. Size the bond area off the load, not off the tape thickness.
• 18 lb/in peel is strong for a clear tape, but peel is still the weakest direction on any acrylic foam. If the design leaves an exposed edge that can be picked at or wind loaded, add a mechanical edge detail or go to a wider strip.
• Bonds on contact with no cure, no mix, and no dispensing equipment, so the part moves down the line immediately instead of sitting in a fixture.
• The 1.0 mm foam conforms to smooth and slightly irregular surfaces, so it tolerates a bond line that is not perfectly flat and handles the slight bow you get on a thermoformed or extruded part.
• 212°F long term and 320°F short term covers dark color solar gain on exterior glazing and brief process heat. The -40°F floor covers cold climate outdoor service once the bond is made.
• The closed cell structure is wind and water resistant, so the tape seals the joint at the same time it bonds it and there is no separate gasket to install.
• Clear on both faces, so it holds appearance in visible bond lines on glass and acrylic where a grey or white foam would read through.
• 24 month shelf life at 40 to 95°F. Keep rolls out of a hot truck bay or an unconditioned mezzanine, and avoid conditions where condensation forms on the roll.
• Test on your own substrate in your own process before you run production. Published values come from lab panels, and surface finish, coating, and cleaning practice all move the result.

Common Applications

• Sign and display: bonding acrylic and polycarbonate faces, light box and cabinet assembly, trimless letter work, POP displays and retail fixtures
• Trailer and specialty vehicle: window and lens trim, interior glazing components, marker light and applique mounting where a clear bond line is required
• Metal fabrication: stainless, anodized aluminum, and coated aluminum panel assembly where fasteners cannot show and welding would distort thin gauge material
• Cladding and facade: glazing components, infill and spandrel panel attachment, rainscreen and trim details
• LED and lighting: strip light and linear fixture mounting, clear lens and diffuser attachment
• Appliance and electronics: display windows, bezels, touch panels, and decorative trim
• Replacing rivets, screws, spot welds, and liquid adhesive anywhere a visible fastener or a weld seam is unacceptable

For opaque panel bonding in trailer, metal fab, and cladding work, the grey and white grades usually carry the volume. See the full VST line for VST6110, VST6120, and VST6160.

Available Sizes and SKUs

Every size sells as a single roll with volume pricing at higher quantities. Custom slit widths and 72 yd rolls are available, call for lead time.

Related Products

• Chem-Set VST3050C Clear High Bond Tape, 20 mil for thinner bond lines
• Chem-Set VST6150C Clear High Bond Tape, 60 mil for less uniform surfaces
• Chem-Set VST3025C Clear High Bond Tape, 10 mil for thin, flat, rigid assemblies
• Full Chem-Set VST tape line including grey and white general purpose, low temperature, and low surface energy grades, with the complete cross reference chart
• Bonding clear acrylic and polycarbonate if you are weighing tape against a UV, MMA, or solvent cement approach

Frequently Asked Questions

What is Chem-Set VST6100C used for?

VST6100C is a 40 mil clear double sided acrylic foam tape used for structural bonding where the joint is visible. Typical work is sign faces and light box cabinets, trailer window and lens trim, stainless and anodized aluminum panel assembly, facade glazing components, LED strip mounting, and display and appliance trim. It replaces rivets, screws, spot welds, and liquid adhesive in assemblies where a visible fastener or weld seam is unacceptable.

Is VHB the same thing as acrylic foam tape or high bond tape?

Yes, these all describe the same category of product. Acrylic foam tape, high bond tape, double sided structural tape, and VHB tape are the same thing. VHB is 3M’s trademark for their acrylic foam tape line, so other manufacturers call the product high bond tape or acrylic foam tape instead. Chem-Set VST is our house label acrylic foam tape line.

Can VST6100C replace 3M VHB 4910?

VST6100C is the closest Chem-Set match to 3M VHB 4910. Both are 40 mil clear acrylic foam tapes supplied in 36 yd rolls on a 3 in core, and both are used to replace rivets, screws, spot welds, and liquid adhesive in visible joints. It is not a 3M approved substitution and the two manufacturers do not publish identical test conditions, so the right answer for your assembly comes from testing it in your own joint. Call us for a sample roll. One practical difference to plan for: VST6100C needs the surface at 65°F or warmer at application.

Can I buy one roll, or do I have to buy a full case?

You can buy one roll. Every width is stocked and sold individually with volume pricing if you need more, and in-stock orders placed by 2pm Eastern ship the same day. Case quantities and multi-week lead times are the usual reason a shop calls us looking for another source in the first place.

Which clear VST thickness should I use?

Match the thickness to how flat and how rigid your parts are, not to how strong the bond needs to be. VST6100C at 40 mil handles most clear bonding work. Go thinner with VST3050C at 20 mil when both surfaces are flat and rigid and you want a minimal bond line. Go thicker with VST6150C at 60 mil when the surfaces are less uniform or there is more thermal movement to absorb. When you need more strength, widen the tape rather than thickening it.

Does VST6100C bond polypropylene or polyethylene?

No, not reliably on its own. VST6100C is formulated for high and medium surface energy surfaces such as glass, acrylic, polycarbonate, stainless, galvanized steel, and anodized or coated aluminum. Polypropylene, polyethylene, TPO, and similar low surface energy plastics need either a primer or one of the Chem-Set VST 78xx low surface energy grades. Call us with your substrate and we’ll point you at the right one.

How cold can it be when I apply the tape, and how cold can the finished assembly get?

Apply at 65°F (18°C) or warmer. Below that the adhesive is too firm to flow into the surface, and the bond will underperform no matter how much pressure you use. Service temperature is a different question: once the bond is properly made, the assembly holds down to -40°F. If you regularly bond in an unheated shop or outdoors in winter, use the VST 8247 or VST 8262 low temperature grades instead.

Where is Chem-Set VST6100C made?

VST6100C is manufactured in South Korea and stocked at our warehouse in Huntingdon Valley, Pennsylvania. In-stock orders placed by 2pm Eastern ship the same day.

Questions on fit for your bonding application, or working from a 3M part number you can’t get? Call (800) 220-1966 or email [email protected].

3M and VHB are trademarks of 3M Company. Chemical Concepts is not affiliated with, authorized by, or endorsed by 3M. Third party part numbers are referenced for product identification and cross reference purposes only.