Thread: FMT grid spacing

I just read a bit about the spacing of the holes. It seems that the hole spacing is based on a standard line boring rig that has 32mm spaced holes. Apparently a throw back to post WWII requirements for mass production.
If you space the holes at 100mm the Kapex feet wont fit but that is the only disadvantage I could find.

I didn't know what a line boring rig is. I Googled for images but still don't understand the relationship between them and the FMT grid (except of course that it is a multiple of 3 x 32mm). Anyway, the fact the Festool designs some of its equipment to slip into the grid is probably a handy little feature.

Also being discussed here.....

A Real Workshop

fletty

thanks for the tip fletty.

Originally Posted by rev

I didn't know what a line boring rig is. I Googled for images but still don't understand the relationship between them and the FMT grid (except of course that it is a multiple of 3 x 32mm). Anyway, the fact the Festool designs some of its equipment to slip into the grid is probably a handy little feature.

Hi rev. I have had nothing to do with Festool gear so are unitiated. However I understand the concept and history of "Euro cabinets". As suggested this evolved after WW2, with the Germans being masters of the art of standardisation. They developed the "Euro cabinet", where cabinet hardware from hinge brackets, shelf pins, drawer slides and other assorted hardware that might be used is arranged in steps of 32mm. To facilitate this, they also developed relatively cheap tooling to gang drill the mounting holes for the hardware. The rig refered to comes in a couple of forms, a stand alone one and one that mounts into a normal drill press. Basically they a long arm with multiple spindles (an odd number) arranged along it in 32mm increments. The whole set is powered from a motor or input shat at the centre spindle and generally drive transfers to the adjacent spindles via a gear at each spindle. Of neccessity, this reverses the direction of rotation of every second spindle, so the odd numbered spindles rotate clockwise (normal drill), and the even numbered spindles rotate anticlockwise (reversed drill).

Because standardised hole layouts were being used, you could quickly set up the rig with the appropriate drill bits in the spindles to match a drilling pattern, set a fence and a stop, then run a batch of cabinet sides through the drill rig, drilling multiple holes with a single plunge. You might be running a batch of say 1000 RH cabinet sides, with 9 holes each near the front and the back edges. A single plunge drills the front hole set, and the component probably moves on to a similar rig with fence and stop set for the rear holes, where a single plunge again drills a matching set of holes. A third unit might be used to drill holes for the hinge mounts.

The 32mm system itself is still standard today for hinges, draw slides etc, but it is more common to prep the panels on a CNC which does all of the cutting, drilling etc from a standard toolset. However every so often I find a drilling rig, generally in a corner well away from the new gear, and normally kept because it wasn't worthwhile to find and pay someone to take it away.

I assume (as suggested above) that Festool followed that standard when they laid out the hole pattern for the table top.
multispindle adaptor.jpg

Great stuff malb! Thanks for taking time to explain this.

I got a bit of mdf cnc'd similar to this MultiFunction Slab Work Bench - Multi Function Slab. Used 96 spacing just in case there was some magic too it, thought 100 would be more rational but wasn't going to use it for measuring.
I made it a bit bigger and added a few things too it. i use the oval clamping holes around the edges a lot. If you go the cnc route, I suggest you take a dog (the one that you put in a bench hole) so they can confirm a slip fit. Mine where tight (19.8 or 20mm can't remember). Got it done in satin melamine mdf as that is what was onhand. Easy to clean glue off, and write dimension on.
Can now do super accurate and perpendicular cross cuts with the rail dogs.

Are you in Adelaide by chance? How much did it cost to get the CNC routing done, if you don't mind saying?

In sydney. Still waiting for the bill. Guessing it would be $100 or so for machining. If you send a drawing to a local cnc mob they should quote you pretty quickly. Or ask a joiner with a cnc to do it between jobs, they may not charge the setup fee a dedicated cnc mob would