Blum undermount question

[Jeff Monson]

Working on a kitchen job right now, using blum undermounts for the drawer runners. I've used them in the past, I have always cut the 1/2" deep by 9/16" wide groove on the back of the drawer for the runner. On this project I'd really like to finish the drawers and install the bottoms afterwards.

My question, Is it ok if I leave the back of the drawer 1/2" short, so I can slide in the bottom and pin nail it after finishing? This would not leave me the 9/16" notch that the runner fits in. Seems logical to me that the locating pin on the rear of the drawer would be sufficient but I'd like to make sure before I proceed.

[Don Wacker]

Thats how alot of factory cabinets are made.

Don

[Peter Quinn]

I think that should work fine. I always make that notch a bit wide on my own drawers (I just whack it out with the BS), the locator hole in the back really does the job, and gravity does the rest in use. We buy prefab dovetail drawers that come prenotched, and theirs are just a bit wide too. Its not a snug fit, its more of a minimum clearance issue.

[Jeff Monson]

I think that should work fine. I always make that notch a bit wide on my own drawers (I just whack it out with the BS), the locator hole in the back really does the job, and gravity does the rest in use. We buy prefab dovetail drawers that come prenotched, and theirs are just a bit wide too. Its not a snug fit, its more of a minimum clearance issue.

Kind of what I was thinking Peter, I just wasn't quite sure if the rear of the drawer would "walk" side to side without a notch.

[Lewis Ehrhardt]

Jeff here is a website that might help
http://www2.woodcraft.com/PDF/77B74.pdf (http://www2.woodcraft.com/PDF/77B74.pdf)

[Paul Grothouse]

Instead of boring the hole at the back of the drawer, just make the drawer sides long and the drawer bottom long and shorten the back and dado it short of the back. The back pin on the slide will engage the drawer bottom instead of the hole. This was orginially the basis of this slide design, when people would dado the back of the drawers and dovetail the fronts. This has changed to the hole in the back of the drawer primarly because the the cheap CNC dovetail drawer manufacturing techinques developed in the last 10-15 years.

I think Norm made his drawers this way in his kitchen cabinet project. He covers this in detail in the series.

[Peter Quinn]

Kind of what I was thinking Peter, I just wasn't quite sure if the rear of the drawer would "walk" side to side without a notch.

No walking IME as long as the hole is drilled precisely in terms of diameter and height. There is actually adjustability via that rear hole mechanism that can raise the back of the drawer up a bit to adjust reveals as necessary, so its the pin in hole connection that has to be precise, not the notch so much. One issue you may have is that there will only be 1/16" of drawer back at the bottom edge of this 1/4" pin hole once you have cut the drawer back to slide in the drawer bottom. I figure 7/16" (distance from drawer bottom to hole center) - 1/4" (drawer tongue thickness) - 1/8" (1/2 of hole diameter) leaves you 1/16" of material. But the drawer bottom should run to the edge of the drawer back if you are sliding in the bottoms post finishing, and that should give you the strength needed to keep it all together. Might be worth making one test drawer to verify? In reality the weight of the drawer and its contents are supported by the slides at full extension, and the slides are held captive by the carcass, so there is little room for anything to move around much.

[Steve Griffin]

I used to finish drawer bottoms separately all the time with Blum tandems.

Just make all your drawer parts normally, and rip off the groove on the back. Slide in the drawer bottom after finishing, and staple the back edge. This also saves the step of cutting notches for the runners---the whole back of the drawer is a notch.

You will have a little cuttout missing from the back corner side. But guess what--once the drawer is installed no one sees it or cares.

I actually now assemble all my drawers normally, and find it's actually easier to finish all together. I don't even sand between coats and tell my clients I purposely leave the bottoms a little rough so stuff doesn't slide around ;)

[Jeff Monson]

I actually now assemble all my drawers normally, and find it's actually easier to finish all together. I don't even sand between coats and tell my clients I purposely leave the bottoms a little rough so stuff doesn't slide around ;)

Steve, that is my normal assembly also. These drawers are for a space saver corner system, There are lots of angles, with 2 small triangle shape cavities in the front. I cant imagine trying to spray those with a drawer bottom in place.

Thanks for all the great info. guys I will proceed as planned!

[Jeff Duncan]

I do mine just like Steve with the exception being that I screw the bottoms on. I figure if your going to build them this way anyway, why not get the full benefit and be able to remove the bottoms in the future if necessary? I also use 3/8" ply as I find it's thick enough for heavy pot/pan drawers, while still fitting within the 1/2" dovetail size so the groove is hidden.

good luck,
JeffD

[Chris Friesen]

Instead of boring the hole at the back of the drawer, just make the drawer sides long and the drawer bottom long and shorten the back and dado it short of the back.

This is certainly doable, but it means you lose some interior drawer length..