Installing heavy duty drawer slides into a project can be a frustrating and tedious task, but there are many things you can do to make the process easier. Because heavy duty drawer slides usually do not have a disconnect feature they need to be installed in a specific way. Some of my installing steps can be omitted or changed, even improved, but the below steps will lead you on a path to success with the least possible chance of error or frustration.
- The drawer box must be sized properly for the opening. It also must be square and not a parallelogram. Your cabinet should also be square. If either is tapered from front to back your slide will bind. Most of our heavy duty slides have ¾” installation width, which is for each side, meaning that the drawer box must be at least 1-1/2” smaller than the opening. Making the drawer box about 1-9/16” smaller than the opening allows some room for error and expansion of the drawer material without the slide starting to bind up. Adjust these dimensions to the actual drawer slide specifications you are purchasing. Also, these slides will need to be mounted directly to the cabinet wall and be secured with an appropriate fastener all along the length of the slide. This means using most of the holes that are machined into the cabinet member slide. This fastening method applies to the drawer box as well. This prevents twisting of the slide as the heavy load shifts along the length of the slides. Please note that we do not recommend mounting the slides flat, especially on any sizes over 24”, as this puts the weight on the minor axis of the slides and reduces the weight capacity by as much as 75%, but never more than 150 lbs. at 18" length. At best, you will have a springy drawer, at worst the weight will pry the ball bearings out of the bearing races and the drawer will collapse and possibly injure someone. If you don’t have a cabinet side wall to mount to, we have mounting brackets that will allow mounting to the floor.
- Remove your new slides from the shipping box and check that they move freely. It is possible that the bearing spacers have gotten out of center in the slide, a full stroke, closed, then open all the way, then closed again, will recenter them. Protect the slides from any dust, dirt or debris during the assembly process, or storage.
- Beginning assembly, have a flat level surface large enough for your drawer box and slides when they are fully extended. If you’d like you drawer box to have some clearance below it, you can shim it up with some ¼” plywood, or whatever dimension you prefer, at each corner. Just make sure it’s all the same thickness. Put your slide next to the drawer box and Index (this is especially important that this be accurate for locking drawer slides) the front of the slide to the front of the drawer box with the drawer member, the thinnest part in the middle, so that you can access the first screw hole, temporarily install this mounting screw, then extend the slide to approximately half its stroke, and add another screw at full extension for the last screw hole at the back. Repeat this process for the other slide on the opposite side. Now remove all the screws and slides. This allows you to have preset holes for the final assembly.
- Take you slides now to the cabinet. Mark a square or level line on both cabinet walls where you want the bottom of the slide/drawer, or offset from the previous step. If you’re installing a long slide I highly recommend temporarily screwing a ledger board or fixture at the line, a 3/4" thick board will support the weight of the slide while you’re screwing it the cabinet wall, you can also clamp it to the wall to make it even easier. An additional option is to make this ledger board into a full mounting fixture by screwing an additional board at 90* on the edge of the ledger so that the drawer box can sit on it for the final assembly. With this option, you’ll need to make the ledger board almost as long as the slide when fully extended. No that you have the leger board attached to the cabinet wall, index the front the slide to the front edge of the cabinet and clamp it, then screw the cabinet member to the cabinet, access holes are available at the front, then start extending the slide to screw in at the back and all along the length. Repeat for the opposite side. Don’t remove the ledger boards yet. Extend your slides fully, then position the drawer box between the extended arms of the slides and align the screw holes then refasten three from step 2 and then test your drawer and make sure there are not binding issues. If you drawer travels freely, but with a bit of resistance, you’re good to go! Now go back a finish screwing into all the holes along the drawer member.
Good luck with your project! Please consider OVIS for all your woodworking and industrial hardware needs