A discussion of practical ways of building cabinets with melamine exteriors and laminate interiors. October 13, 2010
I am bidding a commercial project which specs melamine interiors and laminate exteriors. I do not bid a lot of commercial melamine type projects and would like some feedback on the process I have decided to use. I plan on building all the boxes with .75 G1S melamine, edgebanding the exposed edges and then laminating the outside of the panels with the spec. laminate after widebelting the panels. We will use contact adhesive applied by spray gun. I will construct all our door and drawer fronts using a laminate to match the interior as well as edgebanding and then the spec. laminate for the exterior of the doors and drawer fronts.
I am trying to keep balanced panels as much as possible. This is not an AWI certified project from what I can tell in the drawing or bid packet and it is a public institutional job. I do however want to provide the best possible product and still be in the hunt as far as numbers go. I would appreciate any feedback.
(Architectural Woodworking Forum)
From contributor O:
First of all be very sure that this is not an AWI certified project. The method that you describe would not be compliant with any grade construction and if inspected you would have to address the unbalanced panels on the doors and drawer fronts. Also, if you have an AWI Quality Standards Illustrated, check out section 400B-T-2 which discusses balanced construction as well as lamination over existing overlays. I would send an RFI to the architect asking if the unbalanced construction is what they actually want.
From the original questioner:
The only areas I was planning to have unbalanced panels in would be the exposed sides of the boxes. I would be using a particle board core and matched laminates for the doors and drawer fronts creating balanced panels there. I apologize if this wasn’t clear in my original post.
From contributor O:
Melamine interiors with finished P-lam ends are fairly common. This is directly from the QSI, eight edition, 400B-T-2: "restrained components, such as cabinet sides (gables), may be fabricated with HPDL on one side of the substrate and a different material (cabinet liner or Thermoset decorative overlay, for example) on the other side. The risk of warp for these components is very low." The G1S is the way to go with these parts rather than trying to scuff one side of the G2S and getting the laminate to stick over the melamine, not recommended at all. Balanced construction is required for all non-restrained components such as doors and drawer fronts (400B-T-4)
From contributor U:
Probably 90 percent of what we do is fabricate HP Lam exterior melamine interior casework. Although we are not an AWI certified shop our standards meet or exceed their standards. We used to laminate melamine panels on one side as you are suggesting although we have edge band after cutting parts from full size laminated panels for many years. We now only purchase laid up panels 1side HP Lam 1side cabinet liner for all our door, drawer front and exterior finished panels – upper, bottoms, ends and etc. The lead time is usually only seven to to days and the cost $76 per sheet is less than we would pay for the laminate and sheet of melamine, let alone the adhesive or labor cost. Of course if you must band before laminating this will not work but I have not seen anyone do that, around here anyway for a long time.
From contributor O:
Being an AWI shop or not does not mean that you produce inferior quality products or that there is anything wrong with your cabinets. However, you cannot say that you meet or exceed AWI standards when you have unbalanced door and drawer front construction, which is strictly prohibited for all grades in the AWI standards. I am not trying to pick a fight or debate the quality of your cabinetry. I am simply pointing out that unbalanced door and drawer construction does not meet AWI specs and should not be construed as such.
From contributor C:
We use similar construction as described, been doing it for years. We always use g2s melamine and scuff end gables with belt sanders, have had very few problems. We edgeband gables with p/lam same color as exteriors. For doors and drawer fronts we get glued up laminate, same laminate both sides. Only place we use backer grade is for the underside of counter tops. After we cut our doors we run them through the edgebander. We probably do 75% of our cabinets this way.