Prefinished Versus Unfinished Plywood for Cabinets
For a moderate up-charge, pre-finished plywood saves a lot of labor and finishing materials cost. December 2, 2010
Question
I have always used prefinished ply for my boxes. I finish ff's, doors, drawers, end panels, put boxes together, out the door. This past job I got a slamming deal on unfinished ply, so I shoehorned all the pre assembled cabinets in the sprayroom and did it that way. What are you all doing? I have used prefinished for five years, but after talking to a few guys at the last home and design show they all looked at me like I had two heads when I talked about my construction methods. I found more time tied up in unfinished, and more money tied up in prefinishing. I'm on the fence now.
Forum Responses
(Cabinetmaking Forum)
From contributor Z:
I prefer to use pre-finished ply. It costs about $25 more per sheet, but I think it is well worth it, as I do not enjoy spraying boxes.
From contributor Y:
Prefinished for me. For the money I can't spray the interiors.
From contributor S:
I guess it depends on whether you’re building custom or high end custom. I myself would feel bad selling custom or high end cabinetry with tape lines or hairlines in finish or even scratches in the prefinished ply.
From contributor Z:
I'm not sure what you mean by tapelines. The pre-finished ply that I use looks great. Sure you do need to be careful not to scratch it, just cut good side up.
From contributor J:
I really don't see how you can finish plywood (especially after assembly) for expensive prices than using pre-finished plywood. I occasionally use unfinished ply on some custom applications, but I will still pre-finish it before assembly. I also think that the finish on pre-finished ply is fairly tough and durable. There are some scratch issues, but you just need to be careful. Figure your labor and material to finish boxes (don't forget handling time and clean-up time), and I think you will agree.
From contributor S:
So do you all pre finish f/f then glue to box or do you tape off interior then squirt f/f? When you need to attach wood to pre finished face of plywood what kind of glue are you using? How do you assemble a painted kitchen? You must be dadoing all cabinet parts?
From contributor K:
I use a combination of the two. Prefinished saves a lot of time and shooting, sanding inside a box is a pain. I shoot the face frames and end panels after assembly. Most of my construction is dado, but I don't see where that matters so much.
From contributor U:
After reading your statement I would consider making a final decision based on whether you have more time or money. If you are like me, you may find from job to job this could change. If our shop is busy and our time is limited, but money is more plentiful due to the large number of orders and deposits, we increase our use of prefinished products. This also helps us stay on track with delivery dates by speeding our production time. If we are slow and we have lots of time, but money is less plentiful, we do more in house finishing. I still keep an eye on the cost and profit, but if my orders are backing up, I will sacrifice some profit to purchase prefinished goods, just to keep the customers happy and the final checks coming in on the completed orders.
From contributor J:
We use 3/4" shop grade birch plywood (unfinished). We stain the faceframe and the outside end panels and the bottoms of our uppers. We do not stain the inside of the box. We leave the back off, spray the box, then spay the back laying flat. When the cabinets are done we install the back. Leaving the back off saves us a tremendous amount of time and prevents blowback and overspray. We can finish a cabinet fairly quickly this way.
From the original questioner:
I agree with backs off, don't understand why anyone would finish with backs on. I will say that I'm not a big fan of handling boxes in the spray room. With prefinished I can assemble the box, then bring in the ff, put in the drawer, put on the doors and end panels, then off the assembly table ready to go out the door, a lot less moving stuff around. With the current job it made sense to post fin because the oak ply I got was not expensive. We've been discussing this quite a bit the last few days in the shop, that's why I asked.
From contributor K:
Think of it this way. Prefinished average $25-$30 extra per sheet. But remember, you have to add the finish materials, extra sanding sheets, and the labor to finish/sand the boxes. Not to mention you add another step to your process that can add a bottleneck. That $25-$30 difference for the prefinished is a bargain in the end. We've used prefinished for years, and I have never had a customer complain. Most likely it is because rarely anyone looks inside a cabinet and says "ooh yuck, prefinished interiors" (you don't add your own melamine coating do you?). So if you are already using prefinished and not getting complaints, you could push more products out the door with prefinished and make more money in the end.
From contributor G:
No question in my book. Good quality domestic prefinished maple plywood can't be beat. The finish is tough and the sheets are a breeze to handle but they do seem to leave sharp edges as my hands are covered with tiny cuts. Well worth the extra costs.
From contributor S:
Out of all you that have posted, who builds long runs of cabinets with 1 piece 1 1/2 f/f? Let’s say you have 8` run of wall cabs. Against the wall on the left is an end panel and on the right there is a painted inset with pre finished interiors! 18" single door left, 36" range hood, 18" single door with 24" 2 door and end panel on the right and flush bottom rails with interiors to reduce chipping. This would dado everything for gluing and if I’m not mistaken stretchers and backs are not glued.
From contributor U:
Here's how I typically do this. The size of my preassembled runs for base and uppers is determined by access to the room. If I can gang up a run of individual boxes into an 8' section (including a corner cab.) that section would have a fully assembled face frame attached. I use biscuits and glue to attach the face frame. The boxes are assembled as a unit - laid on their backs on lifts - back edges that is, as the 1/2" backs are kept off until the face frames are clamped on through the open boxes. The frame parts are assembled with pocket screws and glue. Finished ends are attached to the face frames (miters on stain grade, biscuited butt joints on paint grade) and so are attached to the cabinets along with the face frames. Yes, I like that the top of the bottom rails are flush with the cabinet bottoms. Backs are attached with staples and screws. All doors and drawers are fitted before leaving the shop. Does that answer?
From contributor S:
Contributor U - are all your sheet goods pre finished and finish f/f then attach to boxes?
From contributor U:
The answer is yes. I build separate toe bases or some variant.
