Drawer Box Advice

[bstern]

Hi all, I am a closet manufacturer and currently make my drawer boxes out of matching 3/4 melamine. Thinking about switching to doweled wood drawer boxes.

I can buy 2 sided 1/2" prefinished "imported" birch for about the same as wood grain melamine, about $30.00 a sheet.

I am thinking of making sides and bottoms out of this 1/2 material. This will keep my stock down.

My method would be 5mm dowels on 32mm.
Cut, Dado for bottom and vertical boring for the dowels would be done on the bot. Then take front and backs to horizontal boring machine. Assemble and pin nail to avoid clamping.

Questions:
1: Anyone have any experience with 2 sided 1/2" imported birch? (not baltic birch)

2: What do you think of the construction method?

3: Using 1/2" ply, do I need to leave room for expansion on the bottoms?

Thanks
Bob

[Gary Campbell]

Bob...
We have just started offering a CNC cut draw box to our customers. Some specific and general answers are:

1) The Chinese birch is full of voids, delaminations and chunks of most anything off the floor, including metal. We were not able to use it for large parts, small parts would be worse. We have found a very nice 5/8" (1/2" is available) that we use for our draw boxes. It runs $46/sht locally. $24 for 1/2"

2) if you have other operators in your shop, this out to 2nd machine may work for you. We, and others have adopted a CNC cut tenon dado draw box that requires no secondary machining, hence could yield lower cycle times. Don Thomson has the lead in this dept.

3)We use eCabs for our design and cutting and our bottoms have .020 clearance into the dado and .010 on the sides of the slot.

Hope this helps, Gary

[bob_s]

Bob;
Be careful with the plywood if it's from China! I just finished some pieces that seemed fine until the weather changed and then small blisters showed up on the B side of the Chinese B/C natural birch plywood. I showed the lumber wholesaler and the said - yup it is an increasingly common problem. Luckily the pieces were still in the shop. From now on I will make every attempt to avoid Chinese plywood. It is cheaper - But...

[bstern]

HI Gary,

Thanks for the response.
I will be careful with the material.

i did a search on the tenon dado and this thread was the best I found:

http://www.talkshopbot.com/forum/messages/29/21849.html

How to you cut for the bottoms?

[dlcw]

Bob,

As Gary indicated I have used blind mortise tenon joinery exclusively in 5/8" prefinished baltic birch for all of my drawer boxes. I use either 1/4" or 1/2" prefinished AMERICAN maple ply for the drawer bottoms fully inset into dados on all 4 sides of the box. Drawer bottoms are 1/2" from the bottom of the drawer sides to allow for Blum slides.

Once all the drawer sides comes off the CNC it's a simple matter of taking them to the EB25 edgebanding machine and putting prefinished edgebanding on the top edges of the drawer sides. Makes them look like solid maple drawers.

Avoid imported Chinese plywood. I had 3 sheets completely delaminate and also found some non-wood looking stuff in two of the sheets. Thank goodness I was using the cheap sawblade that came with my cabinet saw to cut the material. I would have been really $@(*)$@ off if it had been a good plywood blade or one of my compression bits on the CNC. Like particle board, Chinese plywood is not allowed in my shop and my customers are REALLY happy because of that rule.

I use Titebond II yellow glue along with pin nails as "clamps" and I can assemble many, many drawer boxes in a day. I have a squaring jig I put the parts in to ensure the box is square prior to pinning.

I use eCabs and Shopbot Link for all of my drawer part cutting but have been known to put together layouts in Partworks when I have only one or two boxes that are not going into cabinets designed in eCabs.

My clearances are set to .015 for the depth and .007 width. These settings are for my machine only. Your mileage my vary. With these settings I can assemble a drawer without pins or clamps and it will stay together. Super nice fit. Took about 5 tries to get it dialed in but now it is really nice.

Don
www.dlwoodworks.com (http://www.dlwoodworks.com)

[bstern]

Hi Don,

Thanks for the info.
I am still trying to figure out how to cut the dado for the bottom on the front and back?

thanks Bob

[dlcw]

Bob,

The front and back require either a flip operation on the 'Bot or in my case a trip to the tablesaw with a dado blade. I can rip through dozens of drawer fronts and backs in a matter of minutes. I use the drawer sides to setup the tablesaw so the dado depth and distance from the bottom of the sides are exactly the same.

I find that for drawers, the tablesaw is much faster then doing flip ops of the 'Bot.

Don

[bstern]

Thanks For all the great response.

I will look into using this box method.

I guess it a matter of choosing horizontal boring and inserting dowels vs. one pass on the table saw.

Seems obvious the winner here.

I have some code to start writing!!

[wberminio]

I also use prefinished "American" maple ply.
It's great for cabinet interiors and drawer boxes.
I cut my boxes with my KCD link. All sizes and joints calculated in the software and cut on the Bot,similar to you guys with the "Link".

I stopped making plywood drawers years ago,because of the work involved.Now ,because of the economy,and because I can do it easily,I'm making plywood drawers again.

[bob_s]

Bob;
If you are not using Ecabs or some other high end software you might want to look at Ryan Patterson's CabinetPartsPro. It makes boxes with any style dado a real easy job. For the price of 250 I could not find anything nearly as fast or easy to learn. I just used a tiny version of an open upper as the basis for my draw boxes and because it is parametric, once i found a configuration that I liked I haven't had to change anything but the draw dimension. It also nests and writes shopbot files really well.

[Gary Campbell]

Bob Stern...
IF you ask HOW we cut to let in the bottoms, the answer is full dado .25 deep. IF you ask HOW we cut them, they are simply the next sheet in the nest. Either 1/4 or 1/2 depending on the budget. Echo what Bob Schlowsky says on doing this parametrically. Now that we have seeds for each of these types, it takes under a minute to design and another minute or 2 to nest and have a file spooled to cut.

Here is a pic of two of the styles I use. They are designed slightly different than Don's, as I eliminate the Flip op so all cutting is done from one side. Since these are plywood, we treat them as economy draw boxes, our upgrades always use solid wood.

Heres a couple screen shots that give you an idea of the machining: (note that the notches for undermount are included)

6719


6720

The upper draw box has blind dados to allow much faster edgebanding. The lower requires hand work to trim the EB into the corner. (L & R Sides)
Gary

[wberminio]

Gary-That's exactly how we do it.

[loriny]

Gary, in the upper photo are your tenons on the front and back full thickness or are they machined part way through to allow for wood glue to work? I presume this is Prefinished plywood.
Lorin

[Gary Campbell]

Lorin...
No to the machining on the mating face of the tenon. Yes to PF plywood. As stated above, these are an economy product that are held together with staples and/or screws. Our normal product is dovetailed solid wood.
Gary

[ken_rychlik]

I vote for Don on this one. Even though going back to a table saw is considered "wrong" by some people.

Don if you take a cabinet and turn it into a drawer box like this one, you can make any size drawer fast and easy in ecabs without having to build a cabinet just for the drawer. This is just a modified upper cabinet.

Kenneth
6721

[dlcw]

Here's the drawer that I make regularly. It is 5/8" baltic birch sides and 1/2" drawer bottom. All parts are prefinished two sides. On the top of each drawer I edgeband with prefinished veneer using the EB25 bander.

[dlcw]

Here's the drawer that I make regularly. It is 5/8" baltic birch sides and 1/2" drawer bottom. All parts are prefinished two sides. On the top of each drawer I edgeband with prefinished veneer using the EB25 bander.

Cuts are 60% of material thickness. Bottom dado is 1/4" into the sides. Blind tenons are inset 5/8" from the top of the drawer sides.

Don


6722

[dlcw]

One other thing I do is where glue mating services have the PF on them I use my cabinet scraper to scrap the finish away ensuring proper glue bond. Takes about 30 seconds per drawer. Gotta keep the scraper sharp though.

Don

[nat_wheatley]

Bob,

Why are you moving away from the matching melamine for the drawers. The uniform thickness is nice, it makes use of some of the smaller pieces in the nest that might otherwise be scrap, and you could use RTA construction, which would allow you to do all machining on one face of the panels.

[bstern]

Hi Nat,

I had 2 reasons for looking away from 3/4 melamine drawer boxes.

1. They are darned heavy and bulky to lug around.
2. Offer an upgraded product option.

I never really gave much thought to using RTA construction on drawer boxes.

You are correct about the yield. All side parts come out of what would be scrap and thus increasing my yeids. I do not have to stock separate drawer box material. I am able to nest the boxes with the rest of the job out of the same material.

The biggest problem I have is I cant staple through a 3/4 melamine side. I am nailing it with 2" brad. I have not had a problem with a box failing yet. I do feel I could build a better box.

You have really got my mind going on the RTA assy.
The big bonus would be flat packing to the customer site. Assembly on site should not be that big of a deal.

As far as the wood drawer boxes, I think I need to check on material. I don't do that many boxes so keeping 2 different materials for sides and bottom would not be efficient. Neither would the nesting yield. So all 1/2" or all 5/8 will be my choice.
I think I will probably do something like Don's with one pass on the table saw for fronts and backs.

Thanks all for all the input!!

[beacon14]

I'm using 3/4 melamine and Rafix fittings, two per corner. The fittings face the front and back so are not seen once the box is installed and the front attached. We preassemble, staple the bottoms on, and mount the guides in the shop. Pretty economical and a great use of the material.

Now you have me thinking about the solid wood upgrade option.

[gene]

David,
What are rafix fittings? Could you post a photo?

[wberminio]

Gene -
Here is a source:
http://www.hafele.com/us/products/9061.asp

They are knock down fittings that can easily be adapted to the Bot

[gene]

Thanks, I think i'll think on that one.

Don do you have any problems with the eb 25 tape holding , or coming loose?

[dlcw]

Gene,

With the temp set to between 450-500 degrees, I've never had a delam, burning or discoloring problem on unfinished or prefinished heat activated veneer tape.

I did go through the trimming alignment procedure very carefully to get a better trimming job. This is basically the alignment of the trimming cutters to the guide wheels. Now when parts come off the machine it's a simple matter of using a buffing wheel attached to a drill to get a superb finish. Eventually I'm going to build a table with an auto-feeder and upper and lower buffing wheels that I can take parts off the edgebander and run them through the buffer. Once time permits.

Don
www.dlwoodworks.com (http://www.dlwoodworks.com)