Dust Frames for Dresser

[Dan Gill]

I'm planning to make two Mission style dressers from the plans in one of last year's Wood magazines (sort of). That plan has the case made from birch plywood, which has always seemed very heavy and sort of clunky to me. I want to modify the plan and make the case from dust frames. (Please correct me if my terminology is wrong - I'm thinking of a frame made from 4/4 wood with a thin plywood panel in the center - much like a frame and flat panel door.) In an effort to save on hidden materials, though, I've been wondering about building the frames from strips of hardwood ply. I'm thinking of rails and stiles made from 2 1/2 or 3-inch strips of plywood, probably joined with pocket screws. My drawers would be of hardwood, with glide tape for the slides.

Any thoughts on this? I realize this is not exactly traditional, but that doesn't concern me as much as strength and durability. And of course, cost is an issue or I wouldn't be considering this.

[Norman Hitt]

Others may have different thoughts on this, but I wouldn't trust the strength of this combination of materials. It just reminds me too much of the cheaply made storebought furniture. There's too much work involved to scrimp that much on the material, IMHO.

I don't see any problem using the plywood to make the actual internal "Dust Frames", or internal dividers, but Not for the Case Frames. How are you going to treat the exposed edges of the plywood strips that are the rail and stiles for the end case, where there will be some exposed ply edge between the face and the groove/slot for the 1/4" ply panel?

[Herb Blair]

Dan,
I don't see anything wrong with using plywood for dustframes. You may want to make the frame members a little wider that if you were using hardwood. I would glue the plywood panel in place. This will give it a lot of rigidity. I've used plywood on several chest projects and they worked out fine. I also have a work bench with plywood frames in my shop and some of those drawers have at least 100 lbs. in them..
As far as using UHMV or Teflon tape for drawer runners, I wouldn't, as time will cause the adheasive to let go and then you have a mess. The plywood will wear over time, so I would inlay a 3/4 strip of hardwood (maple is best) in the frame about 1/16" proud of the surface of the frame for the drawer to ride on.

[Fred LeBail]

When I build a Dresser with dust dividers my secondary wood of choice is Pine.
I build the frame using Mortise & Tenon joinery which gives me the strength . A 1/4 " panel of Masonite or some other less expensive material is used to complete the dust divider. They are installed in Dadoos that cut in the frame. Same as a panel door.



Fred

[Jim Becker]

I build them with 2" strips of birch plywood and pocket screws. Fast. Strong. Cheap.

[Scott Parks]

I have used plywood for my dust frames many times. However I would not use pocket joinery for them. I use mortise and tenon joinery and glue the plywood panel in place. I can whip out mortise and tenon joined flat panels using my table saw in no time at all. When you glue up and clamp the panels, you can shoot the joints with 5/8" brads and use the clamps for the next panel. I also make cabinet doors in this fashion.

[Jim Becker]

I have used plywood for my dust frames many times. However I would not use pocket joinery for them.
Just curious...why do you prefer not to use pocket screws (and glue) for this application? I used to do them with tongue and groove (essentially cope and stick) but that took more "work" than the pocket screws do now. M&T is an order of magntude more work than T&G, especially for joints that have any stress spread out over "long distances"...IMHO, of course.

[Dave Brown]

Hi, I may have made that exact dresser last year, was it about the april mag. issue, w/ option on tqall legs or short? I did it w/ short legs and they wanted all 3/4" plywood for dividers, it would have been HEAVY!!!!!!!!!!!!!!!!!!! and I instead did cope and stick frames, 1/4" plwood in middle, it was fine and as it was this thingh is a BEAST to lift, I cannot imagine w/ all the pyywood!
take care, dave

[Scott Parks]

Just curious...why do you prefer not to use pocket screws (and glue) for this application? I used to do them with tongue and groove (essentially cope and stick) but that took more "work" than the pocket screws do now. M&T is an order of magntude more work than T&G, especially for joints that have any stress spread out over "long distances"...IMHO, of course.
Hmm..., Jim, that's a good point. I use pocket joinery all the time for face frames (solid lumber)... But I'm hesitant to use them in plywood.. In my mind, plywood just doesn't hold a screw well. With that statement, I'm sure I just opened a can of worms for discussion. Just a personal preference, that's all. That's why I prefer the cope and stick over pocket holes in plywood.

[Jim Becker]

Hmm..., Jim, that's a good point. I use pocket joinery all the time for face frames (solid lumber)... But I'm hesitant to use them in plywood.. In my mind, plywood just doesn't hold a screw well. With that statement, I'm sure I just opened a can of worms for discussion. Just a personal preference, that's all. That's why I prefer the cope and stick over pocket holes in plywood.
Scott, the glue is the key...you don't just use screws. Once the glue is cured, the wood will splinter before the joint parts! Frames made this way are extremely strong. In fact, I'll admit that some of the face frames on my kitchen project were made with birch plywood using pocket screws and glue...the edges were filled with spackle before spraying...hee hee

[Dan Gill]

Thanks for all the suggestions. I had already planned to use pocket holes and screws for joining the frames. That's just too easy and fast to pass up. I like the idea of inlaying the hardwood strips for the drawer to run on. I'll have to look into that. Now I just have to find the QSWO for this bedroom suite. I think I have that tracked down now.

Dan

[Scott Parks]

Oh, yeah. I just remembered the biggest reason that I use cope and stick. You have to dado the edges anyway to accept the panel. It only takes a couple minutes to put a tenon on the adjoining peice. Hmmm... I've got an idea..... I'll be right back......

[Scott Parks]

First of all, take this for what it's worth. I claim to be no expert. I did this for grins and giggles only... So here's the story. I joined some peices of plywood with pocket screws and TiteBond II. I let it dry at 70+ degrees for 11 hours. It took only about 5 pounds of force to break this joint. Granted, in a dust frame situation, there would be no stress on this joint anyway. Plus it would also have a panel glued into it for added strength.

Note how the screw splits the plywood as it enters. Also, note that the plywood edge under the head of the screw also failed. Most of the glue joint stayed intact, but the plywood failed....

More to come tommorow night!!!

[Dan Gill]

First of all, take this for what it's worth. I claim to be no expert. I did this for grins and giggles only... So here's the story. I joined some peices of plywood with pocket screws and TiteBond II. I let it dry at 70+ degrees for 11 hours. It took only about 5 pounds of force to break this joint.

Good to see an experimenter here. However, you have set up an end-to-end joint. I'd be more interested in seeing an end-to-edge joint as in a face frame. I'm sure it can be broken, but It shouldn't be much weaker than a cope and stick joint in the same materials. In fact, I'm going to try that tonight. Don't expect results before Thursday, though.

Dan

[Jim Becker]

Dan, although I'm comfortable with using pocket screws and glue with plywood for this, Scott's demonstration is good. Since this is plywood, there is no "end to end" orientation, per se... Of course, the type and quality of plywood will make a big difference in this application. Some material is prone to having layers tear out like is shown in the pics. You will be less likely to have this happen with BB or other "many ply" materials.

One thing that puzzles me from Scott's pictures, however, is how "flat" the screws appear to be oriented to the wood. My pocket screw system puts them in at an angle.

[Scott Parks]

Dan, although I'm comfortable with using pocket screws and glue with plywood for this, Scott's demonstration is good. Since this is plywood, there is no "end to end" orientation, per se... Of course, the type and quality of plywood will make a big difference in this application. Some material is prone to having layers tear out like is shown in the pics. You will be less likely to have this happen with BB or other "many ply" materials.

One thing that puzzles me from Scott's pictures, however, is how "flat" the screws appear to be oriented to the wood. My pocket screw system puts them in at an angle.
Jim, I agree that Baltic Birch would be more durable, and have far superior results. I used a standard ply such as would be used in carcasse construction (scraps as origianally suggested for the dust frames.) I use a generic pocket hole jig clamped to my wood. The screws are at more of an angle than it appears. Also, I used #8 screws. A #6 may not have split the plys. I simulating building a frame in the rail and stile method.

Dan, in an edge joining situation, I would not hesitate to use pocket screws in plywood. It would probably be much stronger than joining in this method.

This was a non-scientific experient, and I claim to prove absolutley nothing. I just thought it would be fun to go out to the garage and fondle my tools.:D

Expect a follow up experiment tonight!

[Dan Gill]

I'll see how my tests come out. This is all intensely interesting.

[Dan Gill]

. . . This was a non-scientific experient, and I claim to prove absolutley nothing. I just thought it would be fun to go out to the garage and fondle my tools.:D

Amen to that! I'm always looking for a better/cheaper/faster way, and for an excuse to build something. Especially with a new tool. When I got my planer, I planed wood away to nothing just for fun.

[Ken Salisbury]

The original question in this thread was on making dust frames. In my my close to 60 years making furniture I have made what you might call a "considerable number" of them. Of course these were all before the neat "pocket hole" thingee's (of which I now have a Kreg Pro). In the past I used 2 methods of construction for their frames. Either half lap or mortise/tenon. I would never even consider using plywood for such an application for numerous reasons which I will not elaborate on. Probably 90% of those made were made using poplar. Just because a piece is hidden from view is no reason to use sub-standard material. "Cheaper is never better"

[Jim Becker]

I would never even consider using plywood for such an application for numerous reasons which I will not elaborate on. Probably 90% of those made were made using poplar. Just because a piece is hidden from view is no reason to use sub-standard material. "Cheaper is never better"Umm...while I agree that using solid stock is probably the best choice for casework that also uses solid stock construction (being careful to accommodate wood movement through proper grain orientation, etc.) for plywood casework, which many folks tend to do these days for any number of reasons, using plywood for the dust frames also makes sense. They are compatible materials. "Cost" is irrelevant, IMHO.

Like you, I'm "solidly" in the solid stock camp for almost all that I do, other than things like kitchen cabinets, etc, and would use either the same species or poplar for internals. But I'd certainly choose plywood for plywood carcases, both because it goes together well and it's an excellent way to make the most efficient use of material, including scraps!

[Ken Salisbury]

Umm...while I agree that using solid stock is probably the best choice for casework that also uses solid stock construction (being careful to accommodate wood movement through proper grain orientation, etc.) for plywood casework, which many folks tend to do these days for any number of reasons, using plywood for the dust frames also makes sense. They are compatible materials. "Cost" is irrelevant, IMHO.

Like you, I'm "solidly" in the solid stock camp for almost all that I do, other than things like kitchen cabinets, etc, and would use either the same species or poplar for internals. But I'd certainly choose plywood for plywood carcases, both because it goes together well and it's an excellent way to make the most efficient use of material, including scraps!

I was referring to the application of plywood for the dust frame construction. Of course plywood for case construction is another situation all together. Even the dust frame's I have made in the past have been with poplar frames and 1/4" ply inserts - sorry I wasn't too clear on my response.

[Jim Becker]

Sorry, my wording was obuse, too, Ken. I was refering pairing plywood for dust frames in plywood carcasses and solid stock for dust frames in casework made with solid stock. My bad!

[Scott Parks]

The results are in. Back to the original question relating plywood dust frames.

Picture 1 shows a completed frame, minus the plywood panel. This is using the cope and stick method, all cut on tablesaw. Each tenons is nailed with (2) 5/8" brads. Total time, start to finish: 14 MINUTES! (And I work slow!) That includes set-up, cut, glue, clamp and nail. No blade changes, no router setups, no drilling/screwing; just fast and simple. My point here is that it is very fast and easy to make these! As for using them as dust frames in casework, using leftover ply scraps; I think it is appropriate. (depending on the peice of furniture)

Picture 2 shows the damage after breaking the joint apart. It still broke fairly easy, but it took much more force than the experiment with pocket screws. Note where the breakage occured. The tenon stayed intact. (I thought the tenon would break off). The failure occured from the plys separating and breaking apart.

Conclusion: Hmmm... I don't really have one. But here are the facts.
1. Strength. As far as strength goes, I think the cope and stick was a little stronger. Neither joint was very hard to break. So with that being said, solid lumber would be far stronger than plywood. In both experiments, the plywood failed, and I feel that solid lumber would hold up better. Also, if using plywood, you would be gluing a panel in the groove which would add strength. In a solid lumber situation, the panel would float, so the plywood panel glue-up may actually be stronger.
2. Efficiency. My VOTE is for cope and stick over pocket screw. If I were making these frames with pocket screws, I would have to: Cut frames. Set up pocket jig. Glue/screw. Set up router to rabbet a panel into place. Too many steps.
3. Durability. I have no opinion here. Two thoughts. If a heavy drawer were riding on this panel, I would vote for solid hardwood. If a carcasse were racked or twisted while moving the peice of furniture, my OPINION is that the plywood dust frame COULD pull apart over time. However, when I broke both of these joints, I levered them apart, not pulled them apart.

So there you have it.... I was not trying to prove ANYTHING or ANYONE, or who's right or wrong. I just tried two methods of joining frames for the FUN of comparison.:) And point out MY observations.
YOU BE THE JUDGE!

[Scott Parks]

Couple more comments...

Using Baltic Birch for the same experiment would have probably had far better results with pocket screws. I may be building a large entertainment center soon, and I might use BB for frames.

Second, my old Craftsman table saw was mounted on a plywood box. I built a plywood frame exactly like this for the top of the box. It held up the 100+ lb. tablesaw for many years, and never failed.

[Dan Gill]

I ran my own experiment to duplicate Scott's original one with pocket screws in a plywood frame. In my test, I drilled the pocket holes in the rail and drove the screws into the stile. I glued it up and let it dry for about 24 hours. I did not make a full frame, but just an L-shaped assembly (one rail attached to one stile). There was no splitting of the plywood in the stile, possibly because I set my drill clutch to avoid that. This was ordinary cheap plywood with five fir plies between the extremely thin hardwood veneers.

When I clamped the stile in the vise, the assembly resisted the strain well in all but one direction. But it was fairly easy to break when pushing the rail down, toward the direction of the pocket holes. It seems as if the pocket holes themselves weaken the plywood substantially. The separation was basically around the holes. This makes sense, as a 3/8 inch drill bit takes out a large amount of material making this hole.

In all honesty, the kind of forces I applied to this joint just won't be applied to a full dust frame in a dresser carcase. But seeing how and when things breaks helps us learn.

Now to experiment with a biscuit joint. This is fun!

[Dan Gill]

Well, I ran the biscuit joint test. It was VERY disappointing. I made it much the same as my pocket hole test, with one biscuit joining two pieces of 2 1/2 inch hardwood veneer plywood at right angles. After drying time I put the long piece in the vice and pushed on the short piece. It snapped very easily, and mainly along the glue line. Perhaps not enough glue? But I had plenty of squeeze out.