The LR32 and Blum's Process32 unbalanced system

[fshanno]

I use Blum's Process32 system with the unbalanced panel.  It's a little more complicated than the balanced panel systems but it's better for me.  Why?  For two reasons.  

You are always referencing from the front and from the bottom.  The top and the back can basically run wild, within reason.  

Second, it's perfect for Tandem glides which is about all I use.  Balanced 32mm panels don't give me the optimum placement of that bottom glide on base cabinets with drawers.  And base cabinets with drawers is about all I'm doing lately.  It doesn't take much talking to talk people into springing for drawers vs. doors on their base cabinets.  If they can't afford dovetail drawer boxes fine, I'll nail some plywood together to make a box and we'll stick a nice drawer front on it and call it a day.  Those glides work so smoothly and because the sides carry zero weight even a relatively flimsy drawer box will hold up just fine for years and years.  And if you go with soft close there's even less strain on the system.  

Anyway, it's 46.5mm from the bottom to the first hole.  The case is 30 1/2" tall so top/bottom balancing is out of the question.  This is all kind of important for base cabinets with 3 and 4 drawers because you don't want to waste any space at the bottom.  

So, I know there must be a bunch of folks using the LR32 to make Process32 cases.  If it's okay to ask, how are you doing it.

Maybe this should be in the How To but it could affect purchasing decisions too.

 

[peter halle]

Hopefully Brice will be able to visit and give guidance, but in the meantime you might want to take a look at this video that Brice made that uses the parallel guides in conjunction with the LR 32 system.  It may give you some ideas.

Brice's LR 32 and a parallel guides video

Peter

 

[fshanno]

Hopefully Brice will be able to visit and give guidance, but in the meantime you might want to take a look at this video that Brice made that uses the parallel guides in conjunction with the LR 32 system.  It may give you some ideas.

Brice's LR 32 and a parallel guides video

Peter

Very cool.  For a balanced panel where you don't need all the holes this method would rival a small line boring machine.  The fly in the buttermilk is that Tandem slides don't work with a 37mm offset from the back of a standard depth case so the notion of rotating the panel for the back row won't work.  But seeing it does help. 

I do have a set of parallel guides and based on what I see here a system utilizing them for unbalanced panels could be devised.  I'm going to need a custom stop to attach to the bottom of the guide for initial setup to get that first hole 46.5mm from the bottom.  Set the stops on the parallel guides and have a couple of story boards to put between the stops and the work piece to get the piece in the right position for each row.

So I feel very comfortable ordering the router sled thingy and the 55" hole guide.  I won't need all the other stuff because it's all for balanced panels. 

I've never seen a Blumotion style soft close draw glide that would work with a balanced panel without including unused holes.  Salice has the same hole pattern as Blum and so does then newer TopSlide undermounts that Rockler is offering.  So, we need a solution for Blum Tandem.  When I get it rigged up I'll post it. 

Incidently, you don't need to pay $32 dollars for a pair of 21" Blumotion slides.  Check with A&H Turf. 

And just out of curiosity, if you are using 1/4" backs in dados with a 3/4" offset for back stretchers how do you use a balanced panel in the first place?  You're killing an inch or 24mm of that 37mm.  Seems like the rows would look funny, unbalanced actually. 

 

[Brice Burrell]

.....I do have a set of parallel guides and based on what I see here a system utilizing them for unbalanced panels could be devised.  I'm going to need a custom stop to attach to the bottom of the guide for initial setup to get that first hole 46.5mm from the bottom.  Set the stops on the parallel guides and have a couple of story boards to put between the stops and the work piece to get the piece in the right position for each row......

Sounds like you've pretty much got it figured out. 

.....And just out of curiosity, if you are using 1/4" backs in dados with a 3/4" offset for back stretchers how do you use a balanced panel in the first place?  You're killing an inch or 24mm of that 37mm.  Seems like the rows would look funny, unbalanced actually.

There's a very simple way around that.  You can set the stops so your holes are 61mm (24+37) in from the edge.  For the front row of holes you slip in a 24mm shim/spacer to get the 37mm setback. 

 

[builderbob]

If I heard correctly in the video, I think Brice mentioned adjusting the measurements of the parallel guides to accommodate a back panel. Seems it would make the most sense to drill all your fronts and then change the backer thickness on the parallel guides and drill all the rear portions. Since they're all balanced panels, it's one change from front to back!

Bob

 

[fshanno]

If I heard correctly in the video, I think Brice mentioned adjusting the measurements of the parallel guides to accommodate a back panel. Seems it would make the most sense to drill all your fronts and then change the backer thickness on the parallel guides and drill all the rear portions. Since they're all balanced panels, it's one change from front to back!

Bob

Yes, I heard that on the second time through.  And of course that would handle it.  The panel wouldn't be balanced front to back but it would be balanced top to bottom.  And that's all you need to make left and right sides interchangeable which is one heck of nice feature of the 32mm system. 

Here's a link to the Blum Literature page.

http://www.blum.com/us/en/02/30/40/index.php

The Process 32 Universal Boring Guide pdf is near the bottom of the list. 

I went ahead and ordered the plate with the centering mandrel and a 55" hole guide.  I think I can rig it up to work pretty much like Brice is doing.  I've got that 46.5mm bottom offset and 56.5mm top offset to contend with so I'll have to make my own linear stops but that should be fairly easy to work out.  We'll see.

 

[ccarrolladams]

As originally intended, the LR32 system was standardized to allow more efficient mass cabinet construction in factories. This was especially critical in Europe following WWII because so many housing units needed to be replace in an era of limited funds and scarce supplies.

At that time I was focused on the custom building of cabinets and related products in the USA. I took the feature that I liked best from LR32, namely the spacing of holes for adjustable shelves, and took with a huge grain of salt many of the other LR32 conventions. I started teaching interior cabinet design in 1952, just after I graduated with a degree in Architectural Structural Engineering. I promoted the use of 5mm holes on 32mm centers for adjustable shelves. Once European LR32mm standard drawer slides reached the USA I advocated also using LR32mm holes on drawer units.

For a long time European style drawer slides conformed to LR32 exactly. Then over the years some hardware manufacturers offered non-standard products. This really does complicate turning designer sketches into finished working drawings.

I totally envy those who can make a living building drawer units using just a single brand of slides. Make a handful of story sticks to space guides the desired distance from the front and bottom and life is good.

Unfortunately for me, I do wholesale custom fabrication. Normally my clients, who are designers, have selected brands and styles of hardware desired by the client. Perhaps some of those clients have side deals with hardware suppliers. Sometimes they want me to buy the hardware, since I do a large volume and often can get a better deal. I have accounts with a whole lot of hardware suppliers, including Blum.

Designing custom cabinets is not simple. Lenders tend to prefer that work surfaces be at standard height above the finished floor. One of the downsides to LR32 Balanced Design was that there was so little room to modify standard height, which at least in Southern California seldom was comfortable for most upscale clients I soon discovered. What I have always taught is that the first thing a designer must obtain agreement with the client is the height of the working surface!

Next, the choice of face frame, European frameless or a compromise which I advocate, needs to be settled.

Then comes the selection of the drawer slide system as well as the hinges. We all know these days there are as many hinge system choices as slides.

After that it is important to settle on the drawer boxes.

When I first saw this topic, Strict LR32 vs Blum 32 Approach, I pulled up my business records from July 2010 onward. Only 20% of our jobs used Blum. The rest is a mixture of 15 other brands. Therefore our working drawing CAD software needs to know all the hole placement of all those slides and hinges. Often for us the best solution is to program one of our CNC nested routers to drill the necessary holes, not all of which are 5mm or 35mm.

Before I owned a CNC router system I owned several Festool OF1010 with many accessories. Since in my own experience Balanced 32 sides are the exception, I have never advocated flipping panels. I also have advocated building the foundation of lower cabinets as a separate unit which includes the tow kick. This "sled" can be scribed to an uneven floor, allowing the bottom fixed shelf to rest on an even surface. I reference both rows of holes from the bottom of base and upper units. When the rear row is not a standard distance from the front, I use edge stops. As supplied by Festool those work fine for 37mm and similar settings. Long ago I replaced the bars on a set of edge stops so I could reach the rear row from the front edge. Yes, making those was not easy, but has saved a lot of time over the years. I also have made various end stops to reference the bottom edge of the panels. The original Festool stops set 16mm and 32mm which often is appropriate, but not with Blum.

 

[Sparktrician]

To piggyback on what ccarrolladams said, I've noticed that there are at least three systems, all within the 32mm concept.  There's the system that has the first hole 9.5mm from top or bottom (for Conformat screws) and every 32mm thereafter, and the ending hole at 9.5mm from the other end.  Then there's the Festool variant with the first hole at 16mm from the end and every 32mm thereafter and the ending hole 16mm from the other end.  Then there's the proprietary Blum system whose sole purpose seems to be to lock people into buying only Blum glides.  Go figure...  The first system seems to be used by Ikea and others in that vein that use the Conformat style assembly.  I can't figure out who uses the Festool system aside from custom manufacturers, but I appreciate its flexibility, and especially so after seeing Brice's video and the way he uses the parallel guides so effectively.  Well done, Brice. 

[smile]

 

[peter halle]

I hope that I will not be insulting anyone, but the concept of the cabinet system is commonly referred to as the 32 mm system.  LR32 is a Festool naming concept.  There might be others who know the meaning of LR in the LR32 designation is based on German, but my guess is that it stands for Linear Rail.

Peter

 

[ccarrolladams]

Hi Peter,

While not arguing with you, over 60 years ago I was reading English language translations of the German articles and books about the then-new construction standards based on 32mm. Over half of those referred to LR32. Consequently I have retained that term in my own articles and classes. Leaping ahead several decades, when I started buying Festools in 2006, I assumed they were not kidding when they called their line boring system LR32. Of course this could be coincidence, so Festool might have been thinking rail.

Over all these years there have been many unfounded concepts published about the standard based on multiples of 32mm.

Just remember originally it was all about getting the most product from the least raw material and using the fewest number of different kinds of components. Therefore it was efficient to have both side identical.

The downside is that even 32mm multiples do not always result in design ideal to every individual client or space. This is why even if we are not installing Blum products, we need to be familiar with unbalanced construction.

Oh, yes, it would be rare to actually start or end a row of holes 16mm into the part. Usually shelf holes are not closer to the top and bottom than 80mm, which is 32x2=64mm plus 16mm or on a Holy Rail 2 holes plus the 16mm offset provided by one side of the end stops. The other side of the original end stops called 32mm eliminates the 16mm offset. The current LR32 connector spaces the holes correctly when connecting two Holy Rails. Then they also provide the 16 and 32mm references, but also 9.5mm for certain hardware. For drawer units sometimes the lower holes are closer to the end than 80mm.

See, this is why we all need to read and understand the hardware installation instructions and drawings.

Despite what I might or might not think privately, I have never publicly accused Blum of using their own standard to lock customers into only using their products. Previously I shared the mix of brands I install during the course of 18 months. There are paying clients who select Blum and for them it is my pleasure to install the Blum goodies of their choice. Other clients desire features not available from Blum. Commonly those other brands conform to the 32mm conventions, yet it is still vital to double check specs and instructions.

My feeling is that if all this was so easy everyone would be in the cabinet business.

 

[AlexThePalex]

LR32 is a Festool naming concept.  There might be others who know the meaning of LR in the LR32 designation is based on German, but my guess is that it stands for Linear Rail.

LR = German: "Lochreihen" meaning "rows of holes".

 

[fshanno]

So, has anybody, other than me, ever actually completed a project in which they conformed to the Blum Process 32 for system holes?

I found the PDF a couple of years ago in the Blum online literature and figured if it's good enough for them, it's good enough for me.  it looked like the way to go.  I knew about the 32mm system in general and True32 specifically so it was familiar. 

So when I did my first frameless cases that's the way I went.  I was just using the little plastic jig with the vix bit.  Ragged holes but everything fit very well.  Then I made my own large jig out of white oak patterned after something I saw on the web.  It was pretty cool, didn't require that you lift the router, just slide it from position to position.  When I dug it out last week I found that the wooden jig has warped so unless I want a gentle curve in my rows I needed to do something.  I've got a 1400, I've got a set of parallel guides.  I'd tried the LR32 at a class in Vegas and liked using it so it wasn't a hard decision.

There is one thing I'm interested in doing and the LR32 will help me accomplish it.  I stumbled across the Kurka jig a few months ago.  Here's a picture.

[attachimg=1]

I can use my LR32 setup to build all sorts of templates that would accomplish the same thing as the Kurka.  Instead of a 5mm bit I'll use a router bit sized for the guide bush.  3/8" I suppose.  I use one face of the template for the left and the other face for the right.  That should provide foolproof alignment.  I could have Process 32 templates, True32, whatever.

 

[Brice Burrell]

....I can use my LR32 setup to build all sorts of templates that would accomplish the same thing as the Kurka.  Instead of a 5mm bit I'll use a router bit sized for the guide bush.  3/8" I suppose.  I use one face of the template for the left and the other face for the right.  That should provide foolproof alignment.   I could have Process 32 templates, True32, whatever.

I very rarely make the same thing twice so I don't have the need for one template although it is a fabulous idea.