Howard and Everyone,
Applied to appropriate tasks in a production situation, line drilling machines can be very effective. However, the stress is on Production Situation!
Back in 1946 when I started making Euro-style cabinets with adjustable shelves, there were no factory-made drill jigs with holes on 32mm centers. I was still working in a machine shop so I used a jig-boring machine to make a 1m long gig from 6mm thick aluminum. That did have replaceable drill jig inserts of I could drill 5mm or 1/4" holes. That served me well until I could purchase a slightly-used line drilling machine circa 1952.
My cabinet shops have always specialized in custom jobs, not production in quantity. Therefore in my us all line drilling machines have proven less than ideal. They were designed for factories. In the Original System 32 standards, no holes were skipped. So nearly always the 25 drills on such a machines were enough. Sometimes the outer drill bits were removed if all you needed were 23 holes. Remember, on a line drilling machine alternate drills rotate in opposite directions, so some are painted orange and others black, so the left-hand bits are put in the correct chuck.
What I found early on was that in custom work hardly ever are all the holes drilled. Most of my customers buying custom cabinets prefer there be few unnecessary holes. That means with a line drilling machine you need to manually remove the unneeded drill bits. Then, and this is very important, after the parts are made using removed bits, those must be put back on the machine. Otherwise what happens is a hole you need will be missing. Trust me, I have made that mistake many times.
Still, I used a then state-of-the-art line drilling machine in my custom cabinet shop from 1960 to 1996. It could drill two rows of up to 25 holes, with the second row adjustable from the fixed row. With that it still was necessary to remove unwanted drill bits, and then put them back correctly.
The time involved in removing bits was not an issue when you made many parts, as in production. But, in custom jobs it is rare to be making more than a handful of identical parts at a time. It is frustrating to remove and then re-install all those drill bits.
So in 2006 when I decided to start another custom cabinet business I felt the Festool LR32 approach made a lot of sense. All I needed to do was make a pencil mark so I could skip holes I did not need. Using Festool Holy rails, an OF1010 and LR32 system I could make accurately 6 identical custom parts as fast as using a line drill after removing bits.
When I build my current shop I bought two CNC routers. I do use those for adjustable hole drilling when other CNC tasks are being done on a particular part. If the only holes are for shelf pins, I can do that as fast with a Holy rail, OF1010 and the LR32 system.
Sure, if you do decide to buy a Line Drill, those made by Felder are very good and fairly priced. But you should also talk to Stiles, a firm that makes many kinds of line drills. But for such a factory you would need pressure beam saws and similar factory-style machines.
BTW, I'm a few miles down the road from you in Monroe!
