Question about Blum Tandem 563 drawer slides and rear mount brackets

[Phillip Mitchell]

Need a little clarity. I don’t do cabinet hardware stuff enough to know the right answer to this. There are some photos below to go along with all the words.

I’m building a large vinyl record storage cabinet that is going to have 12 drawer boxes on 15” Blum Tandem Blumotion slides. Looking at the specs for the drawer slides (+ the interior dimensions I need for record storage) helped me size the drawer and therefore the cabinet opening side to side. The slide paperwork said to add 1 15/16” overall to the inside dimensions of my drawer box for the outside dimensions of the slides and where they mount on the horizontal plane inside the cabinet. I took that to mean that was also where my vertical divider/partition would be as well as I was under the impression that the slides have screws they hold them both down the the horizontal part of the cabinet as well as screwed into the sides/vertical divider part.

In a mock-up yesterday trying to sort things out, I slide the rear mount bracket on the back of the slide and see that it projects out beyond the outer edges/dimensions of the slide about 3/8” on each side. Did I get the wrong rear bracket? Do I need to use them?

The issue is that the cabinet size and all the divider locations are already sized based on me adding 1 15/16” to the interior drawer box dimensions as per the slide instructions and I don’t have the extra 3/4” (3/8” on each outer side of each slide) in the current cabinet size. The cabinet parts are not cut to final size yet (or assembled) but I don’t have the extra length to add 3/4” to each drawer bay.

If I need them installed, do I need to make a little notch in the rear lower corner of each vertical divider to allow them to have the correct placement? Even then, one may collide with or touch the adjacent one, but that may not be a problem as long as they are just touching and not overlapping.

All material in this part of the cabinet and drawer boxes is 3/4” hardwood veneer plywood.

Attached the rear brackets I have and now I see the spec sheet on it calling out 15/32” of space that is takes up beyond the outer edge of the slide...

Am I missing something or just thinking about this wrong?

Thanks for any clarity!

[Dan Friedrichs]

That is the correct rear bracket, but you don't have to use it if you can use the screws on the sides of the slides.

Notice that the rear bracket allows some left-right play between the slide and the bracket, though, which can help resolve any slight mis-alignment issues. If you don't use it, make sure your cabinet and drawer are square.

The rear bracket is for a face frame cabinet where there is no vertical divider to screw into. Think of kitchen drawers - the drawers usually sit in a cabinet box with no vertical or horizontal dividers at all - just a face frame and a rear panel.

Here is an example of how they are used in face frame cabinets:
https://s.yimg.com/aah/dlawlesshardw...ide-pair-4.gif

Here is an example of how they are used in panel (frameless) cabinets:
https://www.rockler.com/media/catalo...42-03-1000.jpg

[Paul F Franklin]

If you sized the opening so the slides will be against the sides of the opening, you don't need the rear brackets, just fasten the slides into the cabinet sides. If the opening is wider, you can block out the sides the appropriate amount and screw the slides to the blocks. The rear brackets are only needed with a face frame cabinet where the slides are spaced away from the cabinet sides and you can't or don't want to add blocking to the sides.

[Phillip Mitchell]

Ok, great. Thank you both for the responses. Makes total sense, I’m just not familiar enough with drawer slide hardware to know. This cabinet design is frameless so I will just screw into the vertical dividers and not use the rear brackets.

[Ron Citerone]

I used Blum slides for the first time on my cabinet build recently. Face frame and rear supports. My conclusion is I won’t use the rear supports next time, but I will add strips the sides of the cabinets and screw the glides to the strips. I found the rear supports hard to align and not real strong for a drawer full of silver ware. I might be wrong here, and would encourage more experienced people to chime in if I am missing something.

[David Zaret]

i use pallets of these slides, and i think i can count the number of back brackets i've used on one hand. 98% are mounted to the cabinet sides.

[John Erickson]

Been using Blum Tandem for years building face frame cabinets, I flush the gables to the inside of my 1.5" x .75" frame. Pre-drill the gables for slide mounting 5mm x 11mm euro screw prior to assembly of the box. Once your box is assembled and frames are attached install the hardware.