Guidlines
The DTape thickness required depends on the mismatch between the surfaces to be joined. The more closely the two surfaces fit together the thinner the tape can be. As a general rule, the tape can accommodate up to 50% of its thickness in a mismatch (i.e. the tape should be at least twice as thick as the mismatch). If in doubt, use a thicker tape to ensure a significant area of the tape forms a bond..
When bonding sheets or large pieces, the thickness of the material should not be more than twice the tape thickness, e.g. 1.1mm thick tape is commonly used to bond sheets up to 2.2mm thick.
Thermal expansion and contraction or movement in the joint should not exceed three times the tape thickness. As a general rule, a 2.4m length of plastic can be bonded to metal using a 1.1mm thick tape.
In shear (e.g. holding a sign or panel to a wall) the suggested amount of tape to hold up 1 kg is about 55sq.cm or for:
Standard DTape Widths Tape Length: 12.7 mm wide 430 mm 19.0 mm wide 290 mm 25.4 mm wide 215 mm
These amounts of tape include a significant factor of safety to allow for the different properties of the tapes in the DTape range. These amounts can be reduced by up to 50% depending on the tape type if customer evaluation gives satisfactory results.
The desirable tape application temperature range is 20ºC - 60ºC.
The minimum suggested surface temperatures for DTape application are: 0-16Dc. once properly applied, low-temperature holding is generally satisfactory down to -40Dc
Surface preparation method prepared by the DTape technical Department.
- 1. Most substrates common to DTape applications are best prepared by wiping (in one direction) with a 50:50 mixture of isopropyl alcohol (IPA) and water.
- 2. If there are heavy oils or greases are present there may be a need to first cut the oil with a “degreasing” solvent, e.g. Citrus Cleaner or white spirits, but this should always be followed with IPA/water cleaning to remove any residue .
- 3. Abrasion or scuffing of the surface will in many instances enhance adhesion by increasing the surface area available for bonding. Scuffing must be followed by cleaning with IPA/water mixture .
- 4. The surface must be dry. A good way to assess cleanliness is that a surface prepared for DTape application should be as clean as one being prepared for painting. High surface energy plastics include acrylic, ABS, polycarbonate, PVC, polyester, Polyamide, Polyimide, Phenolic, Noryl. Low surface energy plastics include PVA, EVA, polystyrene, acetal, and some paints. They may require priming with DTape Primer. Very low surface energy plastics such as polypropylene, polyethylene, and EPDM are difficult surfaces to stick to DTape primer may improve the performance on these surfaces.
Apply the DTape to one surface leaving the liner in place. Apply pressure using an applicator or a roller. This ensures contact and removes air bubbles.
Remove the liner, fit the two surfaces together carefully, and using a suitable roller to apply sufficient pressure to ensure the tape experiences 1 kg/cm2 (100 kPa) pressure.
Bond strengths at the minimum application temperature will be achieved as follows:
- 20 minutes 50% 24 hours 90%
- 1 hour 75% 3 days 100%
Assemblies can be handled within 10 minutes but bonds should not be stressed before 72 hours
|
Surface |
Surface Preparation Suggestions |
|
Metals
|
Scuff
if oxidized. For copper or brass apply
lacquer or varnish to prevent further oxidation |
|
Aluminium,
anodized |
Clean
only |
|
Some
plastics & paints |
Scuff,
particularly on paints and hard plastics |
|
Plasticized
vinyl |
Evaluate
plasticizer resistant tapes or prime with VHB Tape Primer 9639 |
|
Wood,
concrete, brick |
Seal
surface with paint, varnish or thin coat of neoprene contact adhesive |
|
Glass/ceramic
surfaces |
Use
Silane Glass Treatment in high moisture or humidity environments |
|
Low
surface energy plastics |
Prime
with Primer D313 and evaluate the suitability of DTape |
|
High
Surface energy plastics with mould release |
Clean
with MEK or acetone (ensure solvents do not affect the plastic), then scuff,
IPA/water wipe |
|
Fiberglass:
Gel coat |
Clean
with any General-Purpose Adhesive Cleaner to remove mould release, scuff |
|
Non-Gel
coat |
Sand
smooth, prime with a thin coat of neoprene contact adhesive or Gelcoat |
|
Scuffing
By hand: By
Machine (Grinder): |
Use
Hand Pads Use Surface Conditioning Discs, medium or fine |