Slides
Center mount drawer slides explained, and the box we build for a single rail under the drawer
Dressers, desks, nightstands, older kitchens and a fair number of bathroom vanities run their drawers on one rail down the middle of the opening. The drawer sits on that rail and slides along it. Nothing mounts to the sides of the box, which makes the box simple, but the height and the bottom have to be right or the drawer drags.
Quick answer. A center mount slide is one rail that runs under the middle of the drawer box, front to back, with the drawer riding on it. It comes as a wood guide in older furniture or a metal slide in newer pieces. The box needs clearance under it for the rail, and the width is usually the opening minus a small clearance each side, so measure the old box. We build to those dimensions. Order a custom box with slide prep None and tell us in the order notes that it is center mount so we confirm the bottom clearance before we cut. Gritly builds the replacement box to your old box’s exact width, depth and height, cut to the 1/32 in, so a center mount drawer gets the same dovetailed box as any other.
How to recognize one
Pull the drawer all the way out and look into the opening. A center mount cabinet has a single track down the middle of the opening floor, front to back, and nothing on the side walls beyond maybe a thin wood strip. Flip the drawer over: a wood center guide shows as a notched block or a pair of strips glued under the back of the box that straddle the rail. A metal center mount slide shows as a light steel channel screwed to the underside of the box along the centerline, with a matching channel in the cabinet. If there is a rail under each bottom edge with a wheel, that is bottom mount; if there is a steel slide on each side of the box, that is side mount.
What we do to the box
- Width. Built to the old box. Center mount drawers are usually a small clearance narrower than the opening on each side, just enough to slide without rubbing, and the old box tells us exactly how much.
- Height. Built to the old box. The rail takes up room under the drawer, so the box height has to leave that room inside the opening. Go taller than the old box and the drawer binds on the rail or the top of the opening.
- Bottom. 1/4 in captured in a groove on all four sides, or 1/2 in if the slide screws into the bottom and you want more for the screws to bite. The bottom is what rides on or straddles the rail, so we confirm how far it sits up from the bottom edge of the sides before we cut.
- Sides. Plain, no prep. Nothing mounts to them.
- Depth. Built to the old box, 9 to 24 in.
Every center mount order gets a look from us before it goes to the saw. You put “center mount” in the order notes, we check that the bottom clearance and height work with what you described, and we ask if anything does not add up.
Wood center guides versus metal center mount slides
A wood center guide is the older of the two. A hardwood rail is fixed to the cabinet floor or the frame, and the drawer carries a guide under its back edge, a notched block or two parallel strips, that straddles the rail and keeps the drawer tracking straight. The drawer’s own bottom edges ride on the cabinet frame or on kickers above them. When you replace the box, the guide block is glued and screwed to the new bottom in the same spot.
A metal center mount slide is a two piece steel slide, one channel on the cabinet and one on the underside of the drawer, sometimes with a small roller. Most are 3/4 extension or less, none have soft close, and the drawer member screws into the bottom of the box at the front and back. Either way, the box we build is the same: plain sides, exact dimensions, and a bottom placed where the old one was.
| Spec | Center mount drawer box |
|---|---|
| BOX WIDTH | Match the old box; usually the opening minus a small clearance each side |
| BOX HEIGHT | Match the old box; leaves room under the drawer for the rail |
| BOX DEPTH | Match the old box; 9 to 24 in custom |
| SLIDE PREP | None. Plain sides; write “center mount” in the order notes |
| BOTTOM | 1/4 in captured in a groove, or 1/2 in for more screw bite; clearance confirmed before cutting |
| SIDE THICKNESS | 5/8 in standard; 1/2 in or 3/4 in on request |
| EXTENSION | 3/4 or less on metal slides; wood guides stop at the drawer stop |
| SOFT CLOSE | Not available on this slide type |
| LOAD | Light duty; check the slide’s rating |
| HARDWARE | Reuse the old guide or slide; we do not stock center mount hardware |
What to measure
Take the drawer out and measure the box, not the front. Outside width, outside depth front to back, and outside height of the side, to the nearest 1/32 in. Then flip it over and measure two more things: how far the bottom panel sits up from the bottom edge of the sides, and where the guide block or metal drawer member sits front to back. Those two numbers are the bottom clearance we confirm on a center mount order. Photos of the underside help. The measuring guide shows the basic three; the find my drawer tool routes furniture drawers to the custom box.
Thinking about swapping the slide for something modern? Side mount needs 1/2 in per side, and undermount needs the runner’s width rule plus room under the box, and an old furniture opening often does not have either. Measure the clearance you actually have, then read the slide types overview or undermount page, or ask us with the numbers.
How to order a box for a center mount slide
Measure the old box and its underside
Outside width, depth and height, plus the bottom clearance and where the guide sits. Snap a photo of the underside while it is out.
Enter it as a custom box, slide prep None
On the custom box, enter the old box’s width, depth and height, leave slide prep at None, and choose Baltic Birch or Hard Maple (Select Grade). Pick the 1/2 in bottom if the metal slide screws into it.
Write “center mount” in the order notes
Say whether it is a wood guide or a metal slide and give the bottom clearance. We confirm it against your dimensions before the box is cut, and reach out if something looks off.
Fit the guide and install
Move the guide block or the metal drawer member to the new box in the same position, set it on the rail and attach the front. The install guide covers the front.
Questions
What is a center mount drawer slide?
A single rail under the middle of the drawer, running front to back, that the drawer rides on. It is either a hardwood guide in older furniture or a light metal slide in newer dressers and vanities. Nothing mounts to the sides of the drawer box.
How do I measure a drawer box for a center mount slide?
Measure the old box: outside width, depth and height to the 1/32 in. Then measure how far the bottom panel sits up from the bottom edge of the sides and where the guide or slide sits on the underside. We build to the old box and confirm the bottom clearance before cutting.
Can I replace a center mount slide with side mount or undermount?
Sometimes. Side mount needs 1/2 in of clearance on each side of the box and undermount needs the runner’s own width rule plus room underneath, and older furniture openings often lack both. Measure the clearance you have and ask us with the numbers before ordering.
Does it matter if the center guide is wood or metal?
Not to the box dimensions, which come from the old box either way. It matters to the bottom: a metal slide screws into the underside, so the 1/2 in bottom option gives the screws more to hold, while a wood guide block is glued and screwed to the bottom in its original spot. Tell us which in the notes.
Do you stock center mount slides?
No. We build the box to fit the guide or slide you already have. If the metal slide is worn, replacements are sold at hardware stores; a wood guide usually only needs the wear point dressed and a little wax.
How to install center mount drawer slides?
For a wood guide, fix the hardwood rail down the center of the cabinet floor and fit the notched block or strips under the drawer so they straddle it. A metal center mount slide fastens to the cabinet at the front and the back, with its runner under the middle of the drawer, so follow the maker’s sheet for the positions. Gritly builds the matching box to the size of your old one. See our how to install drawer slides guide for the general steps.
How do you remove a drawer with a center slide?
Most center mount slides have no release clip to press: pull the drawer straight out until the guide block or channel underneath clears the end of the rail, supporting the front as it comes free. See our how to remove a drawer guide for the steps on other slide types.
A new box for an old rail
Measure the old box, note the bottom clearance, and we build a dovetailed replacement that sits on the same rail. Cut to the 1/32 in, checked before it is cut, built in our Las Vegas shop.