help with sizing Blum Tandem glides... am I reading this wrong?

[Michael MacDonald]

I spent most of my shop time last night scratching my head over this one... I can't rationalize the reality of the hardware to the on-paper specs. Can anyone with Blum experience help me out?

I am installing the 563H series--for the 12 inch length drawer. It says 12-inch in the literature, and the brochure defines the length as the back of the drawer-front to the back of the drawer-back... so if you had a 3/4 inch face, the total outside dimension of the drawer, from front to back, would be 12 3/4... I've looked at it a million times, and this is what I see.

So I built my drawer to be 12 inches, not including the drawer face thickness. But when I am getting ready to install the drawer, I turned it upside down to see how these Blum glides work—and I find that the drawer is ½ inch too long! I need to shim the front locking devices ½ inch away from the inside of the drawer front to enable them to catch on the glide. I have drilled the hook hole in the back, and I can see that the hook is embedding in the hole—so the difference is not the hook.

I posted a pic of the upside down glide with locking devices... the tape measure shows that the distance from the front edge of the locking devices to the base of the hook is 11 1/2. Can anyone with Blum experience tell me what I am doing wrong? I noticed the model number stamped on the glide is 563H305-02B.. the 2 is NOT in model number in the literature—do I have the wrong model? The order form has the right model number... so I assume that is just a convention for their warehouse.

blum measurement.jpg
blum brochure.jpg
I am going to shim at this point. But I would love to know why this didn't work out.

[Jamie Buxton]

.. It says 12-inch in the literature, and the brochure defines the length as the back of the drawer-front to the back of the drawer-back...

There's yer problem. Consider a drawer box intended to get an applied front stuck to the front. That is, the drawer box has two sides, a front, and a back. The 12 inches is the overall depth of the box -- from the back of the back to the front of the front.

[Curtis Myers]

Installed some 563's a few months ago.
what I did was made a moch up drawer out of some junk ply to ensure I had the measurements correct. Thay were only an inch or two tall. The first moch up drawer I made was incorrect so it was worth my efforts to spend half an hour making the mock up.
FYI - My tandems had a setback of 1/8" from the front of the cabinet face frame. I found out the hard way to ensure to get a consistent 1/8" setback. I ended up making a small jig. Worked much better then using a ruler.

Hope this helps
curt

[Michael MacDonald]

Jamie -- I guess you are right. Most of the pics in their brochures are for applied fronts, and they talk about inset drawers and overlay drawers. I had it in my head that I was going to make an inset drawer, but it didn't occur to me that the pics were referencing the back of the applied fronts vs. box fronts... see pic below.


Here is a derivative thought. This glide model is meant to be 5/8 on the side. So since I am 1/2 inch off in length, that would mean that the back hook of the glide is meant to sit 1/8 away from the back of the drawer, and not be seated fully within the bore hole. Would you agree with that? I wonder if that had something to do with Curtis' setback... not sure I understand that. But I can see how making a mock-up is a good idea.

drawer dimension.png

Also, I was so taken up with the math on making drawer fronts angled by about 20 degrees to match the angle of the face frame, that I didn't have any brain capacity left for the blum instructions... here is the drawer... nothing a 1/2 inch shim can't fix... I will get the next set right.
drawer pic.jpg

[peter gagliardi]

Unless they've changed the hardware, whatever the inch size of the hardware is the overall length of the drawer outside to outside eg. 12" = 12" o.a. 15"= 15" o.a. 18"=18" o.a. etc... I have made perhaps a thousand drawers with this method, and it has worked. I will say, their " new" locking devices are a royal PITA compared to old ones. You don't need all those adjustments, you just need to be accurate and know what square really is.
Peter

[Roger Rayburn]

I will concur that I find the literature a little confusing. One of the lessons I actually learned over the years is to order the hardware for a project before I cut the first piece of stock. Having the slides in my hands and seeing how they worked saved me a lot of the kind of grief you are experiencing. That is how I learned how long a 21 inch drawer actually was, not the same 21 inches I thought it was.

[William C Rogers]

I will concur that I find the literature a little confusing. One of the lessons I actually learned over the years is to order the hardware for a project before I cut the first piece of stock. Having the slides in my hands and seeing how they worked saved me a lot of the kind of grief you are experiencing. That is how I learned how long a 21 inch drawer actually was, not the same 21 inches I thought it was.

So how long is the 21 inch drawer if you remember. I am getting ready to build some tomorrow. Will definitely builds a trial just to be sure.

[Roger Rayburn]

Well, it actually is 21 inches from the back of the back to the front of the front (not including the false front). That dimension applies if your front and back are exactly 1/2 inch stock. If it's 15/32, all bets are off. The slide member fits into a hole in the back of the back and then the locking hardware screws to the back of the front. In the first drawers I built using them, there was zero tolerance. They have made some design changes so now you can order locking hardware (an option) that gives you a little wiggle room. I don't do this day in-day out so for me it's still a little stressful.

[Erik Christensen]

From what I know - having built maybe 30 drawers with blum tandem slides. You buy slides for a specific drawer side thickness - 1/2" or 3/4". The specs on length are outside dimensions - so in this case the drawer should be 12" long without false front - measured from outside edge to outside edge. If your stock is off a < 1/16" the rear pin just seats in the back hole a bit more or less. I can tell you stock off by 1/4" is a no-go because I mis-ordered slides one and tried to put a 3/4" drawer on a slide set for 1/2" - that did not turn out well at all.

as long as you have room in your cabinet case to move the slides back 1/2" you should have no issues with the 1/2" shim fix and nobody will ever know unless they take the drawer off the slides and turn it upside down

[Chris Friesen]

You don't need all those adjustments, you just need to be accurate and know what square really is.

You realize of course that all those adjustments were invented so that people didn't need to be as accurate up front, but could tweak things once installed.

[Jim Neeley]

You realize of course that all those adjustments were invented so that people didn't need to be as accurate up front, but could tweak things once installed.

Adjustments will help you with "accuracy" but if you get out of square all bets are off... DAMHIK.. <g>

Well, except I still need to re-make my first-ever shop drawers; they irritate me whenever I use one, I just haven't got my ROUND TUIT yet!

[Gerry Kaslowski]

I just made the same 'mistake'. I just bought one set of 563H to test them out. I agree that the instructions appear to be from the back of the drawer front to the back of the drawer back. I also made a test drawer, and found the length incorrect. The 18" drawer should be 18" in depth, then add on your drawer front. Now it fits.

[Bob Grier]

I have had the same problem. Now, before cutting drawer sides I attach the release hardware to a piece of plywood (1/4") and then fit that to the slide. Then I measure from back end of plywood to front of release and that is the dimension I build the drawer to fit (back of back to back of front). For me, I have a bunch of older slides that I think are 1/2" different than the slides shown in current instructions. Also, my releases do not have all the adjustments shown for new ones. Anyway, the "profile setback" on my slides is 1/2" greater than listed in the current literature. Even doing the mock up, I sometimes have to make small adjustments to some of the finished drawers using shims to make the inset drawer front match the face of the cabinet.

I like the slides but I don't build enough drawers using them to have everything figured out so I have to do the mock up every time I make a new set. I also don't trust the literature because hardware has changed and my slides are older.