Extending the Capacity of the MFK-700

The Festool MFK-700 has pretty amazing dust collection, but the horizontal bases (0º and 1.5º) require the use of pretty short bits.  If you use non-Festool bits, you're likely to run into this problem repeatedly.  I decided to fix that.

This entry is actually the first of three enhancements I'm making to the MFK-700 although arguably this is the most useful :)

Here is one of my favorite bits for flushing banding: a 1/4" spiral down-cut bit.  I have a bearing version I use in the OF-1400, but this bit is what I want to use in the MFK-700.  As you can see, there's an "issue".  This fix is essentially to remove that part of the base to make clearance for the bit or any number of other reasonably short bits.

Addendum: that 1/4" bit works for me, but some others who have done this modification find that they just can't get the base low enough to get the cut perfectly flush, so there's a variance (in one case, though, they did this to the 1.5 degree base).  Anyway, the best bit by far for this modification, and what I now use exclusively for flushing banding, is this 8mm down-spiral carbide bit (#1322) from Vortex Tools.  The larger diameter means you can definitely get it to flush with room to spare, full capacity of the modification, and a down-spiral so the flushing is the cleanest possible.

The portion you have to remove is done in two parts.  First part is marked here.  While this part gives clearance for the bit, it doesn't make the channel where the bit rides wider.  This will be clear in a photo later.

You'll want to "raise" the fence as much as possible to get the top (shown) far from the base (background).  This lets you use the fretsaw on an angle to make these cuts.

I'm using a fretsaw from Knew Concepts along with metal-cutting Pégas blades from Ben's Scrollsaw to cut away the bit clearance.  Yes, these were blatant plugs, but that saw and those blades make a fantastic combination.  Say goodbye to wandering blades ("goodbye!")

Okay, so anybody purchasing a Festool router base knows how difficult it would be to start cutting it up... but it cuts very cleanly with this blade.  You don't need the cut really clean; the second cut will clean it all up along with filing it.

Voilà!  Point of no return :)

For the second cut, we need to remove the bat ears I highlighted.  While they don't give more bit clearance, they make the channel for the stock narrow (the channel being the light portion of the base that is above the lower brown foot).  For this cut, I used a hacksaw to get the crosscut straight.

What's left now is to actually remove the bat ears so they are flush to the offset portion of the base.  Back to the fretsaw...

As you can see, there isn't much room for long passes with the fretsaw so it's slow-going, but you get there.  Cue up a long song.

Take a mill file to flatten the portion where the ears were and clean the edge made with the hacksaw crosscut.  I also used a half-round file to clean the round bit recess and soften some edges.

The final result with the bit having enough room.  Start to finish it might have taken a half hour.  This is a modification I'm certain to enjoy and take advantage of.