# Spraying adhesive



## Julio Navarro (Oct 20, 2012)

I am using a spray gun to apply Wilson art laminate adhesive (contact cement) but my gun spits it out not very uniformly. I am spraying with a compressor at the recommended pressure for the gun. Kobalt from lowes.
Do I need to thin the adhesive? What am I doing wrong?


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## Hammer1 (Aug 1, 2010)

There are special sprayable contact adhesives, ordinary contact adhesives shouldn't be used. They don't spray like paint, there can be spitting. If you aren't in the business, it's a lot easier to use a roller.
http://www.tacadhesives.com.au/products/203-premium-spray-contact-adhesive


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## BZawat (Sep 21, 2012)

Hammer1 said:


> There are special sprayable contact adhesives, ordinary contact adhesives shouldn't be used. They don't spray like paint, there can be spitting. If you aren't in the business, it's a lot easier to use a roller.
> http://www.tacadhesives.com.au/products/203-premium-spray-contact-adhesive


+1 definitely better to use a low-nap roller and disposable tray if not doing production work. Most contact adhesives are not sprayable. Thinning contact cement is never a good idea, it will take away from the glue's adhesion and bonding properties. If you are working with a sprayable adhesive, be sure your gun is made for spraying adhesive and has an adjustment for fan width, adhesive volume, and air volume. Should be sprayed at high pressure, most portable compressors don't produce enough CFM to do it. If not properly done, you can get puddling or striping which will show through the laminate.


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## cabinetman (Jul 5, 2007)

Julio Navarro said:


> I am using a spray gun to apply Wilson art laminate adhesive (contact cement) but my gun spits it out not very uniformly. I am spraying with a compressor at the recommended pressure for the gun. Kobalt from lowes.
> Do I need to thin the adhesive? What am I doing wrong?



If your adhesive is a spray grade it's ready to go. If it's a brush grade, it has some retarder in it, and may be slightly thicker. It can be thinned some with lacquer thinner, but not a lot. When you spray it it will be in a spitting form. If you try to get a smooth output, it will be too thin and flash dry. It will get like angel hair. So, regulate your gun to get a path width 6"-8" at about 12"-18" distance. Solvent grade contact cement can be sprayed out of a conventional ordinary siphon cup and gun. I use the same needle/tip/cap that I use for film finishes, and have no idea what size it is...whatever it came with.:yes:








 







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## Steve Neul (Sep 2, 2011)

I've sprayed a lot of contact cement. Visually it should look like your spraying rubber bands. You should also spray from a greater distance than spraying paint so its half dry and leaves a cobweb pattern on the work. For laying laminate 100% coverage isn't necessary. Just cover the entire surface with the cobweb pattern.

I've also rolled a lot of contact cement too. If you are working with formica when rolling cement it gets the wood wet with solvents more and swells the wood. If you roll it I would wait 24 hours before you trim and file it because the wood will shrink and the plastic won't. Then you end up having to file it again and perhaps overfile it.


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## cabinetman (Jul 5, 2007)

Steve Neul said:


> I've sprayed a lot of contact cement. Visually it should look like your spraying rubber bands. You should also spray from a greater distance than spraying paint so its half dry and leaves a cobweb pattern on the work. For laying laminate 100% coverage isn't necessary. Just cover the entire surface with the cobweb pattern.


That "cobwebbing" is the flash drying I called "angel hair". It doesn't make a good bond to the surfaces. A good bond is from the spitting in small dots that are wet when they hit the surface. The further away you are from the subject, the worse it gets. Most guns, even the cheap ones work with 50LBS -60LBS PSI line pressure. It's not a matter of atomizing the cement, but rather just pushing it out of the gun.










 







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## Steve Neul (Sep 2, 2011)

cabinetman said:


> That "cobwebbing" is the flash drying I called "angel hair". It doesn't make a good bond to the surfaces. A good bond is from the spitting in small dots that are wet when they hit the surface. The further away you are from the subject, the worse it gets. Most guns, even the cheap ones work with 50LBS -60LBS PSI line pressure. It's not a matter of atomizing the cement, but rather just pushing it out of the gun.
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No you misunderstood. I'm not talking about the overspray that leaves cobwebs all over the place, I'm talking about the texture that Wilsonart recommends. The cement lands wet and sticky, it just leaves the pattern.


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## Steve Neul (Sep 2, 2011)

cabinetman said:


> If your adhesive is a spray grade it's ready to go. If it's a brush grade, it has some retarder in it, and may be slightly thicker. It can be thinned some with lacquer thinner, but not a lot. When you spray it it will be in a spitting form. If you try to get a smooth output, it will be too thin and flash dry. It will get like angel hair. So, regulate your gun to get a path width 6"-8" at about 12"-18" distance. Solvent grade contact cement can be sprayed out of a conventional ordinary siphon cup and gun. I use the same needle/tip/cap that I use for film finishes, and have no idea what size it is...whatever it came with.:yes:
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> 
> ...


I would not thin the contact cement with lacquer thinner. The manufacturer has recommended solvents for their cement and I wouldn't use anything except their solvent if thinning is needed. Very likely the solvent is toluene but without knowing the specific cement you are using I would be reluctant to recommend a generic solvent for anything other than clean up.


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## cabinetman (Jul 5, 2007)

Steve Neul said:


> I would not thin the contact cement with lacquer thinner. The manufacturer has recommended solvents for their cement and I wouldn't use anything except their solvent if thinning is needed. Very likely the solvent is toluene but without knowing the specific cement you are using I would be reluctant to recommend a generic solvent for anything other than clean up.


If solvent base contact cement needs thinning, lacquer thinner works just fine.









 







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## VIFmike (Jul 21, 2012)

I've sprayed lots of contact adhesive on vinyl tops and auto interiors such as door panels etc. I've seen it thinned with laquer thinner for many many years.


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## Steve Neul (Sep 2, 2011)

cabinetman said:


> If solvent base contact cement needs thinning, lacquer thinner works just fine.
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I don’t understand how you can stand by that statement. Lacquer thinner and contact cement solvent are two different chemicals. Both are a blend of solvents however lacquer thinner has many more chemicals in it that were never in the contact cement. Most contact cement solvent for flammable liquid cements are a mixture of toluene and methyl ethyl keytone where lacquer thinners commonly contains also acetone, alkyl ester, glycol ether and methanol. The most adverse is wax. Depending on the brand lacquer thinners can contain waxes to retard evaporation and to introduce wax into a cement is a bad idea. Then the lacquer thinner sold in the box stores if formulated primarily as a wash thinner made for clean up. It has a much higher concentration of acetone than the lacquer thinner formulated to thin lacquer. One of the most basic rules in working with adhesives and finishes is to use the same brand of solvent as the product you are using. The companies that formulate these products know best which blend of solvents is best for their product. I can see how it would work to thin contact cement with lacquer thinner however I can see it taking years off the durability of the product. Then if you make people believe lacquer thinner is just as good as contact cement solvent the person that keeps a can of cement for years using a little at a time will end up dumping foreign chemicals into it trying to rejuvenate it every time its used. Before they reach the bottom of the can they are more likely to have a product that is separated and shouldn’t be used for any purpose.


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## cabinetman (Jul 5, 2007)

Steve Neul said:


> I can see how it would work to thin contact cement with lacquer thinner however I can see it taking years off the durability of the product.



I'm guessing it would only be good for 85-90 years.:laughing:



Steve Neul said:


> Then if you make people believe lacquer thinner is just as good as contact cement solvent the person that keeps a can of cement for years using a little at a time will end up dumping foreign chemicals into it trying to rejuvenate it every time its used. Before they reach the bottom of the can they are more likely to have a product that is separated and shouldn’t be used for any purpose.


As with any coating or adhesive, I don't recommend prolonging old stock with a thinning agent or solvent. In the severe case you just mentioned, I wouldn't even use the solvent recommended by the brand...even though it may be twice the cost of lacquer thinner.

For the situation that the OP queried, to spray contact cement, IF NEED BE, lacquer thinner can be used and is used by me and any other fabricator I know of (and I know plenty), without adversely affecting the bonding or lasting ability of the cement.









 







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## VIFmike (Jul 21, 2012)

Guys that use contact adhesive for interiors, vinyl tops etc have been thinning it for many many years with excellent success thinning it with laquer thinner.


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## Hammer1 (Aug 1, 2010)

Lacquer thinner will work as a solvent for solvent based contact adhesive, so will acetone. Using contact for fabric is a different thing than using it for laminated plastic. To bond contact with LP on a substrate you have to use pressure. The adhesive can be compromised in several ways if a thinning solvent is used on LP work. You are better off to use the right product along with the right equipment than to try to make the wrong product work with inadequate spray equipment. If I wasn't doing a half mile of countertop a day, I wouldn't consider using spray, there isn't any advantage to it and there can be a lot of issues.

I seldom do any LP work these days but in the past, I was an architectural woodworker. The amount of LP work we often did was massive. Although we had a separate LP area with a couple of techs, spray booth, pinch rollers and other specialized equipment, at times, everybody kicked in to get those hundreds of lab tops and cabinets covered for the new hospital, or whatever the job was. We all had our rollers and pans. We used the same ones for years, never cleaning the pan or the rollers. Just let them sit a minute in the adhesive and they were good to go. Once about 1/4" of glue was built up and dry, you could peal it off like a rubber sheet. I think a glue covered roller works better than a new one since it's almost like an ink printers roller and applies a nice even coat very quickly and all the adhesive goes on the work, not half soaked up by the roller. I know I can roll a lot of adhesive in the time it takes to clean a gun and not have to worry about anything.


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## cabinetman (Jul 5, 2007)

Hammer1 said:


> If I wasn't doing a half mile of countertop a day, I wouldn't consider using spray, there isn't any advantage to it and there can be a lot of issues.


One advantage is speed. Spraying panels and sheets is much faster, and the adhesive gets applied much smoother. In laminating gloss laminates or paper backed veneer, spraying provides a glue surface that is less likely to read through on the finished face. Gloss laminates show every bump and variation.









 





 

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