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Bob Cooper
12-29-2020, 10:01 PM
Just started using the prefinished plywood for cabinets. I can imagine there’s going to be situations where I would normally use pocket screws and glue to join the face (now pre-finished) to an edge. How do you guys handle this? Use something like guerrilla glue?

roger wiegand
12-30-2020, 7:55 AM
I plane off the finish on the glue surface to reveal raw wood.

Kevin Jenness
12-30-2020, 8:11 AM
I use biscuits. You could try melamine glue.

Andrew Gibson
12-30-2020, 9:28 AM
My question is always what are you expecting the cabinet to sustain with glued plywood edges that it won't with pocket screws alone? If your cabinet gets hit by a Buick you have bigger issues. I worked in a commercial cabinet shop as QC Supervisor building restaurant and hotel interiors for a while. Everything was screwed or crown stapled together, never glued. IMO strength and longevity with ply is more about geometry. My argument is not will the glued cabinet be stronger, but does the project require the added effort to gain the strength. I was the guy that got sent on site to do repairs and deal with failures.

Consider the can of worms opened... :D
PS. I just finished my kitchen remodel with pocket screws and pre finished ply cabinets with no glue, so I'm putting my money where my mouth is. The cabinets I tore out were 30 year old particle board that was crown stapled. They still put up a bit of a fight coming out.

Brian Tymchak
12-30-2020, 9:58 AM
Consider the can of worms opened... :D
PS. I just finished my kitchen remodel with pocket screws and pre finished ply cabinets with no glue, so I'm putting my money where my mouth is. The cabinets I tore out were 30 year old particle board that was crown stapled. They still put up a bit of a fight coming out.

I used pocket screws only for my hanging tool cabinets in my shop. 10 years and they are still rock solid.

glenn bradley
12-30-2020, 10:14 AM
My question is always what are you expecting the cabinet to sustain with glued plywood edges that it won't with pocket screws alone? If your cabinet gets hit by a Buick you have bigger issues. I worked in a commercial cabinet shop as QC Supervisor building restaurant and hotel interiors for a while. Everything was screwed or crown stapled together, never glued. IMO strength and longevity with ply is more about geometry. My argument is not will the glued cabinet be stronger, but does the project require the added effort to gain the strength. I was the guy that got sent on site to do repairs and deal with failures.

Consider the can of worms opened... :D
PS. I just finished my kitchen remodel with pocket screws and pre finished ply cabinets with no glue, so I'm putting my money where my mouth is. The cabinets I tore out were 30 year old particle board that was crown stapled. They still put up a bit of a fight coming out.


The sheet goods I get as a hobbyist are not the quality that a shop that buys it by the truckload gets. I just help my SIL build some drawer boxes for a shop fixture out of something that looks like Baltic Birch ply but, is a bit rougher. The only drawer box that didn't stay square is one where we missed the glue on one corner. The force of the warped sheet goods was enough to tweak the joint. Fortunately with pocket holes we just backed the screws out, glued the joint, put the screws back and clamped the box flat to a surface. Once the glue dried it was fine.

We all have viewpoints and give advice based on our experiences. That is the beauty and the value of forums like this. I appreciate your input and am not taking a contrary position. I am just adding value by sharing my experiences with glued versus non-glued pocket holes. That said I have done plenty without glue when using better materials. I agree that sheet goods construction is strengthened by good assembly methods. The need for glue will be based on what you are building and how you are building it.

Bernie Kopfer
12-30-2020, 10:44 AM
The OP asked a question about what glue will work with prefinished surfaces. There wwas a similar thread the other day and a similar question was not answered. It appears that there is not a glue that anyone trusts to hold to a varnished or painted surface.

Andrew Gibson
12-30-2020, 10:51 AM
The OP asked a question about what glue will work with prefinished surfaces. There wwas a similar thread the other day and a similar question was not answered. It appears that there is not a glue that anyone trusts to hold to a varnished or painted surface.

Good Point, I have not found a glue that I would trust without removing the finish if I needed more strength than screws alone.

Bob Cooper
12-30-2020, 5:58 PM
OP here...thanks. I knew that glue on that joint even on unfinished plywood was pretty unreliable (edge to face) so it doesn’t surprise me that many folks don’t use glue at all and just rely on physics and pocket screws. There’s really not much force on these joints especially in a base cabinet.

Personally I think I’ll use guerrilla glue if I need some additional strength as I think it will bond to the prefinished plywood. I was curious what others did and how concerned they were. So I appreciate the answers to my questions.

That other thread is actually what triggered my question as I didn’t see an answer and thought my use case might be slightly different.

So maybe one more question. When you guys attach a face frame — I know...old school — what method do you use? Me...glue and either nails or pocket screws (pulling the FF in). I have never tried biscuits as it just seemed like it might be tough to align everything and wasn’t sure they were needed as once everything’s together they shouldn’t go anywhere.

Jim Andrew
12-30-2020, 6:27 PM
When I worked at the cabinet shop, we ran a 1/4 x 1/4 groove on the face frame, then machined the side panels so they had a 1/4 x 1/4 tongue, then put glue in the groove, slid the side panels in and then stapled through the tongue into the face frame. We could then take the pressure off, and set the cabinet off to the side to dry, The bottom and top also had tongues that fit in grooves in the face frame. We ran a groove for the bottom and top in the sides as well, and put some glue in that groove before nailing through the side into the top and bottom. Made for extremely strong cabinets, and no nail holes in the face frames. The back was grooved in to the sides, and you could slide the back in before gluing and nailing the nailers in the back, so the box was clean on the inside. We used 5/8" thick nailers.

Kevin Jenness
12-30-2020, 8:11 PM
I use biscuits for alignment. They pull bowed panels into line and keep the face frame from squirming around. I offset the face frame 1/32" from the decks and partitions and ease the back edge. Pocket screws where they won't show, and/or just clamps and cauls. I use clamps in any case to pull the joints tight quickly, pocket screws free up most of the clamps to move on to the next box sooner.

You spend more time filling nail holes than you save, they often show through a paint finish, and who wants to see filler with a clear finish. You can use just pocket screws, but you need to clamp as you go to keep them from pulling the frame sideways and you need to work fast on a big box to get everything fastened before the glue tacks off. The Kreg clamps that fit into a pocket hole are handy, but you really need closely spaced holes to use them properly, and manually drilled pocket holes are time consuming.

Tom Bain
12-30-2020, 8:17 PM
When I worked at the cabinet shop, we ran a 1/4 x 1/4 groove on the face frame, then machined the side panels so they had a 1/4 x 1/4 tongue, then put glue in the groove, slid the side panels in and then stapled through the tongue into the face frame. We could then take the pressure off, and set the cabinet off to the side to dry, The bottom and top also had tongues that fit in grooves in the face frame. We ran a groove for the bottom and top in the sides as well, and put some glue in that groove before nailing through the side into the top and bottom. Made for extremely strong cabinets, and no nail holes in the face frames. The back was grooved in to the sides, and you could slide the back in before gluing and nailing the nailers in the back, so the box was clean on the inside. We used 5/8" thick nailers.

I have used a similar approach with prefinished ply and Roo Glue to bond the tongue in the ply to the groove in the face frame. This is not a speedy method as you need to clamp up all the cabinet boxes.

Bob Cooper
12-30-2020, 9:08 PM
Thx...very helpful

roger wiegand
12-31-2020, 9:37 AM
I've spent enough time repairing broken stuff put together with pocket screws that I would never depend on them in a structural joint. I have used them to temporarily pin kitchen/bathroom cabinet face frames together until they could get glued down and they work fine for that.

Jim Becker
12-31-2020, 11:33 AM
The specific situation with a specific joint would guide me. If I needed the strength of glue, I'd carefully remove the finish from that area and still use polyurethane glue like Gorilla brand plus screws. I will make a custom little sanding block I can run along the edge to only remove not quite to the line, etc., I use butt joints most of the time for cabinet carcasses because it's simple and when glued and screwed very strong. Grooves/rabbits can add some strength and alignment with the extra work required for properly fitting the grooves/rabbits to the actual material thickness. (don't assume anything) I will sometimes use pocket screws, but they are not my preference for carcasses. And an end-cap hides the screws from butt joints very nicely.

Andrew Pitonyak
12-31-2020, 1:40 PM
Having taken apart pocket hole plywood, I can say that the glue added a surprising amount of strength (raw wood, not finished). So glue clearly adds strength to the joint so I always use it (because I can). I have only used pre-finished plywood a few times and I used glue when I would have raw edges touching (like in a dado).

I do not hold a lot of hope that my regular glue will hold to the finish. If I really needed the strength, I would at a minimum scuff the surface and I would probably perform a few tests. To convince myself that I was happy with the strength. I would trust E6000 to hold, but that really is not suitable for this application I don't think.

Jim Becker mentioned using a jig to sand right along the edge. I suppose that you could do similar with a router table and do more than scuff the finish.

John Connelly
12-31-2020, 9:37 PM
Roo glue clear.

David Kenagy
01-02-2021, 3:50 PM
The sheet goods I get as a hobbyist are not the quality that a shop that buys it by the truckload gets.

I’ve been fortunate with a company called “DSI” (Distributor Services International). They sell in bulk to pro shops, but they’ll sell single sheets. Their business model is a little funky...you call their headquarters, set up the purchase, then drive to a warehouse to pick up the order. They’ll take checks or cash, but they add 3% if you want to use a credit card.

Jim Becker
01-02-2021, 3:57 PM
I’ve been fortunate with a company called “DSI” (Distributor Services International). They sell in bulk to pro shops, but they’ll sell single sheets. Their business model is a little funky...you call their headquarters, set up the purchase, then drive to a warehouse to pick up the order. They’ll take checks or cash, but they add 3% if you want to use a credit card.

My sheet goods supplier recently instituted a 3% surcharge for CC purchases. I can appreciate why, but it's a bit harder for small operations that don't have "fully stocked" bank accounts to cover a check since those generally get deposited electronically and immediately. But I figure the cost for that into a project so it really doesn't matter in the end. Many suppliers will cheerfully sell to small operators and hobbyists. Mine even delivers with only a fuel surcharge for a $300 minimum order...which is darn easy to hit. LOL If I need just a little more material to make that minimum I add on something for shop utility or "oops" close out material which is darn inexpensive compared to pristine, but is usually 90% usable material.

Dave Sabo
01-02-2021, 9:36 PM
Before I'd use gorilla glue I would use hot melt polyurthane or even construction adhesive. GG is jsut too time consuming and MESSY for carcass construction.