Bubbles Under Laminate

Help with a visual defects associated with spray contact cement and laminate countertops. April 21, 2011

For years I have used Wilsonart roll-on contact adhesive for making laminate tops. In the last year, I have discovered the benefits of using a spray on contact adhesive. I switched to a Starstuk clear spray on adhesive in the canisters. The problem I have is that I seem to always get lines and round bubble spots that can be seen in the tops when you look at them at the right angle. What can I do to eliminate this problem?

Forum Responses
(Cabinetmaking Forum)
From contributor K:
Cloth, iron, re-heat adhesive, and re-roll.

From contributor T:
I don't know if this is the case in your situation, but back in the days when we did laminate tops, we were very careful to fill all the voids left from seams or screw heads.
Sunlight or a Mr. Coffee Maker, anything that transmits heat, can heat trapped air molecules. As the air gets hot, it expands and lifts the laminate like a balloon would. We would fill these holes with bondo or fixall and sand that down before we glued the surface.

From contributor P:
You have to spray the glue very evenly or the lap marks will telegraph. Another problem with this glue is a very short open time. You have to pay close attention to the time frame from when you spray it to the time you stick it down.

From contributor R:
In a previous life I did quite a lot of laminate work as a small production shop owner. Although my primary interest was solid wood architectural woodwork and furniture, I used to get more than a little enjoyment from plastic laminate... and no, that didn't include getting high off the fumes. Unlike general woodworking, plastic laminate counters, cabinets and furniture offered a predictable, forgiving and mindlessly simple outcome, given a disciplined approach to the work at hand.

Like you (I assume) I evolved from the tedious and messy process of rolling to spraying on the contact cement. I was convinced by the salesman and others that it was necessary to buy a pressure pot, which I did and it worked well. Spraying on the Wilson art (red) adhesive was the mindless part - about 80% coverage of a spidery/pebble like pattern with a quick second coat around the perimeter did the trick. I think you could spray the stuff up in the air and as long as it landed on the surface it would work. Open time was never an issue as working fast was one on the perks of laying down laminate.

After coughing up the price of a pressure pot and gun I soon found that a standard siphon cup set up for lacquer (Binks 2000) would work as well with the pressure set high at about 50-60 PSI. The pressure pot and gun were subsequently dedicated to finish work and the contact was applied with the siphon cup which is more practical for limited production.

I never experienced the issues you describe or had to deal with callbacks after delivery, with one exception - a lab using a Bunsen burner directly on top of the laminate, which charred the chemical resistant laminate into ash... Not what I would consider a glue failure.

I will admit I have no experience with the Starstuck canisters you are using, but why use a glue that has to be "applied like lacquer" when there is such an easy alternative? Overlap telegraphing through a .0625" laminate short of being ladled on would never have been in my vocabulary. Unless there is some overriding advantage for this product, I would stick with the older technology.

From contributor P:
I agree - the older glues were much more forgiving. The reason I don't use them anymore is because it is illegal in my state. The canister setup is very convenient but I think the price of the glue line is too expensive.

From contributor C:
I have done a fair amount of HPL work, not a huge volume. I have a CNC with vacuum hold down. I have been cutting HPL on it for several reasons, one of which is safety. I had the need for some 30 plus sheets a while back and it was not available in the standard grade but was in post form grade, so I just used that. I found some likes in it, one being the black line is a bit smaller. The one thing I could say is that when the sheet is being cut, you can see every line in the spoil board from previous cuts. Another thing could be the sheen of the HPL. Debris is a problem, but I never plug screw holes as long as the main plain is in good shape; it is a fairly forgiving thing to do. Different from stain cabinets for sure.

From contributor M:
Sounds like you missed a spot when you j-rolled it. I find pressure is more important than most guys hand rolling something out realize. Even though it sticks with nearly no pressure at all, it's not a guaranteed permanent bond until it's pressed properly. If not, the problem sounds like issues with your joint not being flush or being able to move. Bubbles could also be trash/debris underneath. We use the same glue (StarStuck, in clear and red).

From contributor L:
It seems the glue is a little thicker than the rolled on type. I have learned to spray the glue in a close parallel pattern, not overlapping as in a spray finish. This will look better in a reflective view. I believe the guns on the market also have a finer tip made for them. There may be a clogging problem with them. Good to always have a spare one in a thinner can.

From contributor N:
It may be the adhesive you're using. Wilsonart is not the best when it comes to contact adhesives. There was a period when I was using Wilsonart. The material bonded okay but not nearly as well as a 3M product. I've been quite happy with 3M, both water and solvent base. It's a bit pricey but it's well worth it. A few of those jobs I used the Wilsonart adhesive on resulted in callbacks where the laminate pulled apart. I also agree with the poster who suggested better surface preparation. I can't emphasize enough how important this is. I use bondo myself. If you're doing a lot of laminate work, you might want to invest in a pinch roller.