If you want easy access to the deepest part of the drawer, you’ll want to install full extension drawer slides.
This is a type of drawer slide that uses ball bearings and a 3-piece rail system for extra extension. You can pick these up at any home store, at various lengths. You’ll want to choose the slide that is equal to or just less than the depth of the side of the drawer.
In this guide I’m going to show you how to install full extension drawer slides on a drawer for a computer desk I’m building.
I’ve already built the drawer, which I detailed in this guide. Now to install the drawer slides, I’ll be using the Kreg drawer slide jig. You don’t have to use a jig to install these slides, and I’ve done plenty of them without jigs. But getting the Kreg jig is one of the better decisions I’ve made for my furniture projects.
I’ll be doing a full review of this jig in a future post which I’ll link to here when it’s complete.
As for the drawer dimensions, you’ll want to read the instructions that come with the slides, or measure their thickness, and use this to figure the final width of the outsides of the drawer.
The extension slides I’m using are 1/2″ thick, so my drawer is 1″ narrower than the opening of the desk that will house the drawer.
What’s Needed To Install Full Extension Drawer Slides
All you’ll need for this process as I’m doing it, are the Kreg drawer slide jig, a pair of drawer slides with the included screws, a drill, and some clamps.
I also use small strips of wood and diagonal cutters to make a simple gauge I use to make sure both slides are installed the exact length from a given reference point. For this guide, that point will be the under-surface of the desktop.
The Installation Process
Mark and Set Your Kreg Jig
I don’t have any pictures of this step, but basically, you want to measure the height of your drawer face, add the gap you want above (I usually go with a 1/8″ gap).
Then make you a pencil mark. Assuming the bottom of your drawer is flush with the bottom of the drawer face, this mark will be the bottom of the drawer and the bottom of the full extension drawer slide. So this will also be where to clamp the Kreg jig.
I do this on one side, then I make the wooden gauge I mentioned earlier. I just take a small strip of shim, and using diagonals I cut it to length until it sits in place:
And using this gauge I can now clamp in place the other jig on the other side. No need to mark, the gauge sets the elevation perfectly.
Now with both clamps in place, we can move on to install the slides in the cabinet.
Mounting The Full Extension Drawer Slides
For this step, you’ll first separate the 2 sections of each drawer slide. If you extend the slide out, you’ll see a release lever. Push this lever and continue extending and pull the small section completely out.
You’ll need to set the larger part of the drawer slide on the jig, 3/4″ back from the front edge of the cabinet face. This allows space for the drawer face:
Then while holding it firmly in place, extend the slide until the mounting holes you want to use are revealed. Mark these holes with a sharp pencil. Do this on both sides. Then remove the slides and the jigs, and drill some pilot holes to take the mounting screws.
You can now use the screws that came with the drawer slides and mount the large section in the cabinet.
Be sure to use the same mounting holes you used when making your marks!
Installing The Drawer
For this part, you’ll be putting the drawer in place using the Kreg drawer slide jigs. Then marking holes and mounting the other section of the slide to the sides of the drawer.
So to start, you’ll swap the direction of the Kreg jigs, and clamp them in place pressed firmly against the bottom of the drawer slide. Most of the jig will be extruding out from the face of the cabinet:
Now you’ll want to re-insert the small sections of each full extension drawer slide. Partially extend them out in preparation for setting the drawer in place:
Now carefully set the drawer on to the Kreg jigs. Be very careful not to bump them hard enough to shift them out of place.
When I install full extension drawer slides with the Kreg jigs, I also use Kreg’s vice clamps. They work really well together, and they hold very firmly. Another cool feature with these clamps is their large clamp faces. When clamped tightly on wood, this reduces the chance of the clamps marring the material.
Once the drawer is resting on the jigs, slide it back until it’s balanced and doesn’t want to tip off forward or back.
Make sure the drawer slides are extended out and touching the back of the drawer face. Then holding the drawer down against the Kreg jig, mark one hole of the slide on the side of the drawer, with a sharp pencil.
You’ll only need to mark the front hole at this time. You will mark the back hole over at the workbench, making sure the slide is perfectly in line.
So with the front holes marked on each side of the drawer, take the drawer back over to your workbench. Pull out the small parts of the drawer slides, remember this is done by releasing that small lever that’s exposed at full extension.
You can also now remove the Kreg jigs from the cabinet. You won’t be using them anymore at this point.
Go ahead and drill pilot holes at these 2 marks on your drawer:
Set your slide in place and screw in the front screw at this pilot hole. If you use 1/2″ plywood to build your drawers, then you’ll want to get some 1/2″ #8 wood screws. Most drawer slides come with 3/4″ screws, which will be too long for our 1/2″ plywood drawers.
Once this first screw is in place, measure the distance from the top of the drawer to the top of the slide. I’m using my combination square to make this really accurate. Be sure to do this right at the point where you installed the first screw.
Now lift the back of the slide up so the measurements match, and mark the back hole. Then you can make your pilot hole and install the back screw.
I would go ahead and sink one more screw in the middle of the drawer slide if it’s very long. Now repeat these steps on the other side of the drawer, and it will then be ready to install.
Putting It All Together
Now slide the drawer into the cabinet. Be sure to align the slides up just right. It’s possible to insert them incorrectly and still slide it back. This could damage the drawer slide, so be careful and insert it properly the first time.
And That’s All There Is To It
So there’s my guide on how to install full extension drawer slides. Sign up below for content like this (and free plans) send directly to your inbox.