# Gluing drawer bottoms?



## petergdenmark (Oct 12, 2011)

I am in the process of building some drawers for my shop, and wondered if there is any problems associated with gluing the drawer bottoms into rabbets?

I realize it constricts the wood movement, but using plywood, that isn't really an issue. Further more - the glue is stronger than the wood, so instead of making a groove that the drawr bottom can slide into, why not just use a router to make a rabbet in the drawer sides, and glue the bottom panel in and reinforce it with some screws?

This being shop furniture, where function beats form, my thinking is:

- Not having to make a groove 1 inch from the bottom, gives you more space in the drawer (this is the most important reason for me).
- Making a groove of about half the drawer material thickness will make it weaker, where strength is most needed. This is avoided.
- Gluing in the panel takes out ratteling.
- If the bottom fails or is damaged (spilling paint or solvent into it for instance), it would be a lot easyer to replace, since you wouldn't have to brake the drawer sides apart.
- The glued bottom would assist more in holding the drawer square.

I follow Matthias Wandel of woodgears.ca, and he always seems to glue his bottoms into rabbets - even the ones for heavy duty use. Now - i'm not saying he's a guru, but he's not the worst woodworker in the world either .

Now if i was to use a solid wood bottom panel, that would be a different story, but isn't the convention of the groove and floating panel just a case of "better safe than sorry" when applying it to sheet material?

Just a small side question: I'm building my drawer sides out of 3/4 (18mm) 11-ply birch plywood, and could save a whole (very expensive) sheet, if i oriented the drawer sides "cross grain" in one of the drawerss, in my cut list. I know it's stronger going with the grain of the outer ply's, but using 11-ply birch, wouldn't it be strong enough anyway?

Thanks - all this plywood and full extension drawer slide business i very unfamilar to me


----------



## cabmaker (Sep 16, 2010)

I didnt read your entire post(life is short) but I would rethink that rabbitt on the drawer bottom. Especially for shop stuff. Why would you consider a rabbett there anyway ?


----------



## madts (Dec 30, 2011)

Peter: I would just slap an over-sized bottom on the bottom of the drawer. 
Glue it and screw it. Then route round the outside. Since this is shop grade, quick and dirty and this is good and strong.

I am from Denmark but live in the USA.


----------



## sillac (Oct 31, 2010)

What kind of drawer slides are you going to use? I use the roller type that hold the weight of the drawer at the edge. I which case I think it would be fine to build the drawer anyway you like. I build mine out of 1/2 ply for the sides, back and bottom, 3/4 ply for the front and for the faults front and glue nail everything together and screw the faults front on. I do use a rabbit for the bottom at 1/2 inch up from the bottom, takes a little longer to make but helps to square everything up.


----------



## bondogaposis (Dec 18, 2011)

For the most part I think it isn't going to make much difference whether you rabbets or grooves for a plywood drawer bottom. I do think that you might get a little more support from the grooves though and I would go that route if you are planning on storing a lot of heavy tools in it.


----------



## SnowyRiver (Nov 14, 2008)

I usually do dados (groves) around the bottom sides/front/back of the drawer sides. Slide in the plywood bottom and glue up the drawer sides. I let the bottom float without glue.


----------



## petergdenmark (Oct 12, 2011)

I make the rabbet because it looks just a little better, and doesn't take that long to make.

I do actually use the method of gluing and screwing over sized bottoms (out of OSB) when i build spruce storage boxes for my loft, and one of them is a 30×20x10 inch box, that holds 200 lbs of free weights, and it holds up just fine.

I'm using the side mounted drawer slides, that screws into the (middle of) drawer side. They are 30 inch full extension rated at 150 lbs, and all the supplier had was 9mm or 18mm birch ply, so i wen't with the 18mm.

But i guess gluing in a bottom is no problem according to you, so what ever method i'm going to use, i will glue them in.

Thank you - and in danish: Tusind tak for hjælpen .


----------



## rance (Sep 30, 2009)

No need to waste an inch with the grooves(or dados). 1/4" below the bottom is fine. Grooves are much stronger than screws. With screws, the weight of the contents is hanging on the number of screws you use. Of course the glue helps too. I'd still recommend going with grooves over screws. You only loose 1/4" + thickness of bottoms.

Oh, and the depth of the grooves should only be 1/3 the thickness of the sides, not half.

With 11 plys, the difference in strength with grain orientation is negligable(IMO).


----------



## HillbillyShooter (Feb 15, 2012)

Don't know how thick your bottoms are, but 1" up from bottom seems way too much. The max I've ever felt the need to use was a 3/8" Baltic Bitch bottom, dado (groove) between 3/4" and 3/8" from bottom; and that was for some really heavy contents. My normal drawer bottom is 1/4" Baltic Birch, dado between 1/2" and 1/4" from bottom. Otherwise, agree with Bondo a nd Wayne on dado (groove) and free float. Good luck.


----------



## NiteWalker (May 7, 2011)

The best way I've seen drawers done, even for shop drawers, is to rout or use the tablesaw to cut a groove in the front and sides of the drawer box, cut the bottom to fit, but a bit longer at the back, and cut the back of the drawer so it sits on top of the bottom. The bottom gets screwed or nailed to the back from underneath. I like this method because it's easy and should you need to replace the bottom it's very easy to do so.

If you use the table saw with the regular blade you can sneak up on a snug fit and have no rattle.

For plywood, use whichever gets you the most yield.


----------



## davidroberts (Nov 8, 2008)

i didn't read all the responses (life just got shorter) but whoever said cut dados in the sides and slide your bottom panel in get my vote. unless you are storing weights, a quarter inch to 5/16 from the bottom leave enough material.


----------



## pintodeluxe (Sep 12, 2010)

Dado for plywood shelves, and glue in place.
If the drawer bottoms were solid wood, then you would just glue the center so the outer edges could expand across the width of the board.


----------



## jeffl (May 3, 2009)

I've always used 1/2" ply for sides and 1/4" bottoms in grooves 1/4" up from the bottom. Never had a failure and some of my drawers are loaded. Put white laminate ply in the bottom so you can see.


----------



## petergdenmark (Oct 12, 2011)

Ok - thank you for the replies fellows.

If 7mm is enough material under the groove to support the bottom, i guess the extra space it takes is not really an issue.

I just don't see how it is sturdier to have a bottom resting on a 6mm deep and 7mm high ledge, that is made up of thin laminated layers of wood (as it is in plywood  ), than having it "rest" on several metal screws that is embedded into the side of the drawer, and reinforced with glue, that is stronger than the wood.

Guess it's just a matter of aesthetics and tradition, and maybe the groove style is the preferred method because it works with both sheet gooods and solid wood.


----------



## petergdenmark (Oct 12, 2011)

Just another thought here in my process.

Another argument for having the drawer bottom flush with the sides would be, that the annoing problem, og things catching on the ledge, when you accidently put something into the drawer, that somehow brushes up aginst the drawer above, and then you can't open the drawer.

Happens all the time with that "all kinds of wierd things" drawer most people have in their kitchen.

Anyway - thanks again.


----------



## PurpLev (May 30, 2008)

I usually groove the drawers and use 1/4" masonite for the bottoms - or you can use 1/2" ply if you are really planning on loading those drawers up (masonite holds real well for me for the past few years even heavier stuff). I groove the drawer sides 1/2" from the bottom at 1/4" width which leaves 1/4" material below the drawer bottom to support it and it supports it all around as opposed to a few screws in certain locations.

I also leave the back of the drawers undercut so the bottom can always be slid out from the back and replaced if need be (and can be replaced with a 1/2" rabbeted material if need be as well which will still fit and not stick out from under the drawer.

I never glue drawer bottoms, but if I use plywood, then I cut the bottoms to exact fit (as opposed to leaving some room for expansion)


----------



## davidroberts (Nov 8, 2008)

Petergdenmark: Those "thin laminated layers of wood (as it is in plywood  )" you referred to are actually stronger than a solid wood board, at least in theory, or 99.72% of the time. The grain in solid wood runs in one direction (not counting burls, etc) so all the strength is tangential to that direction. The ledge of solid wood made by the dado can easily break compared to the laminated plys where the grain direction of each ply alternates 90 degrees from the preceding ply. Those back and forth alternating plys build up a very sturdy rigid material. "Engineered" as they say. Made by God, improved by engineering, at least in this case.


----------

