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Veneer Laminate may be fabricated in the same manner as conventional Formica® laminates, but its composite form requires special care before and during fabrication.
Substrates
The recommended substrates for use with Veneer Laminate are MDF, chipboard and plywood. The substrate must be of good quality, with a smooth surface.
Plasterboard, calcium silicate boards, blockboard and solid timber are not recommended.
Do not bond Veneer Laminate direct to plastered or rendered walls.
Observe all the usual precautions to avoid telegraphing: a clean press area, freedom from dust and debris, and uniform adhesive spread.
Adhesives
Veneer Laminate should be properly press bonded to the substrate using a rigid or semi-rigid adhesive such as UF or PVA. Contact adhesives, particularly hand applied, are not recommended.
Remove any adhesive smear with a damp cloth before curing takes place. Do not use any solvents on Veneer Laminate.
Pressing
Cleanliness in the pressing operation is of paramount importance. Veneer Laminate may be hot pressed, but the press temperature should not exceed 60°C. Cold or warm pressing will produce better stress-free panels. Pressures should be normal for the type of adhesive used, typically 2kg/cm2 - 5kg/cm2 for PVA, and 3kg/cm2 - 5kg/cm2 for UF.
Postforming
Postform Veneer Laminate in the same way as for conventional postforming laminates, using static forming machines. However, the forming temperature is lower and the window of formability is much narrower. The ideal forming temperature is between 140°C and 150°C. The minimum recommended forming radius is 12mm in the longitudinal direction (with the grain) and 25mm in the transverse direction.
Those temperatures and minimum radii are a guide only and may vary slightly with the grain pattern and type of postforming equipment. Postforming fabricators should conduct their own preliminary trials.
The protective film may be left on during the postforming process, but remove it immediately after forming.
It is possible to postform Veneer Laminate on continuous postforming machines, but carry out trials to ensure that the protective film does not foul the rollers. If the protective film is removed, carry out trials to ensure that the forming bars and rollers do not mark or damage the surface.
Machining
Veneer Laminate may be cut and machined using the same equipment as for conventional Formica laminates. TCT saws and cutters are recommended; keep these sharp and in good order.
When cutting double sided panels, take precautions to prevent splitting and break-out on the underside. A scribing saw is recommended, particularly on cross-grain cuts. Lowering the saw blade also reduces underside chipping.
The saw fence must be parallel with the saw to prevent face chipping caused by the back of the saw flicking up the surface.
Trim off any overhanging laminate with normal laminate trimmers using sharp TCT cutters. Make sure that any guide wheels are rotating freely to prevent marking the surface. Do not use cutters with fixed pin guides.
Veneer Laminate may also be trimmed with a sharp block plane, and finished with a file or fine abrasive paper to remove the arris.
Cut-outs and Through-fixings
Veneer Laminate is more susceptible than conventional laminates to the effects of humidity changes, so it is important to follow the recommendations for avoiding stress cracking given under 'Dimensional Movement' in the ‘Design Issues’ section.
Any cut-outs (for access, switches, ventilation grilles, etc) with side length of up to 250mm must have the internal angles smoothly radiused to a minimum of 6mm. Increase this radius pro rata as the side length increases. In general, the larger the radius that can be accommodated, the lower the risk of stress cracking. Where radiused corners are not possible, use butt joints to achieve right-angles.
Where appliances are to be fixed to the face of a panel, bore clearance holes through the Veneer Laminate for screw or bolt fixings. Also provide adequate clearance to holes for fixings that pass right through the panel and into the sub-structure. The minimum recommended clearance is 1.5 times the diameter of the fixing. Countersinking should be in the surface of the substrate, and not in the laminate itself.
Never drive nails through a Veneer Laminate panel. Skirtings, cornices and other applied timber mouldings should be bonded or screwed in place. If screws are used, provide adequate clearance as above.
Edge Lipping
The edges of panels surfaced with Veneer Laminate may be edged by any of the conventional methods. The most sympathetic material is real timber, but edging with Veneer Laminate or with Formica ColorCore® can also be used to good effect.
Do not allow excess adhesive to cure on the surface, as its removal may result in damage. Release agents may be used, but should be first checked on an off-cut to ensure compatibility. Remove any residual release agent carefully. Do no use any solvents on Veneer Laminate.
Seal and finish solid timber edges according to the application.
Counter-veneering
The following table summarises the recommended balancers for Veneer Laminate.
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Category A
Optimum Flatness
(Better than BS 4965 limit)
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Category B
Flatness meeting
BS 4965 limit
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Category C
Sealing purposes only:
flatness not guaranteed
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Laminate identical to that of face laminate
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Universal Backing Board
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Any conventional laminate backing board
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For optimum flatness use the same laminate on both sides (Category A).
Flatness meeting BS 4965 requirements (1mm maximum distortion over 600mm length) can be achieved using the appropriate balancer (Category B).
For small panels, or where flatness is less important, any conventional laminate backing board may be used (Category C).
Finishing
Veneer Laminate is pre-finished so requires no further surface treatment.
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