WoodAnchor™ fixturing grid worktop

 

A portable WoodAnchor fixturing grid worktop, mounted on a DeWalt DWX725B stand

Overview

What can you fixture with a WoodAnchor fixturing grid worktop?  Just about anything you want!

  • Mount hold-down clamps, edge clamps, workpiece stops, or fences anywhere along any fixturing slot.
  • Use F-clamps, C-clamps, or handscrew clamps along the perimeter of the worktop.
  • Use slot-mounted cauls for veneer pressing.
  • Use slot-mounted cauls, plus stops and edge clamps, for panel glue-ups.
Using hold-down clamps to fixture a workpiece on a WoodAnchor fixturing grid worktop
Edge-clamping a workpiece against an adjustable fence, on a WoodAnchor fixturing grid worktop

How it works

A WoodAnchor fixturing grid worktop works like a fixturing plate on a machine tool.  You can fixture your workpiece directly to the worktop, or you can mount auxiliary components such as vises and work supports to create specialized fixturing.  When used as an assembly table, it can quickly be configured for a specific application.

Unlike dog-hole grid worktops, fixturing-slot mounting points aren't limited to discrete locations.  But if you also need dog holes, no problem -- you can add them within the grid cells as you wish.

The worktop pictured here is designed for portability, and it consumes very little floor space when stored on its end.  The mounting brackets can be clipped onto the matching portable work stand, as shown.  Or they can simply be placed on top of a flat surface, where they rest on their rubber feet.

You can also incorporate WoodAnchor fixturing grid worktops into either fixed or rolling benches, if that makes more sense for your shop.  In fact, WoodAnchor fixturing slots are at their very strongest when milled in solid hardwoods, such as the maple or beech that is often used in fine hand-tool workbenches.

The WoodAnchor™ advantage

WoodAnchor fixturing slots absolutely blow away metal T-track in this application.

  • They save hundreds of dollars vs. T-track and T-track intersection kits.
  • Grid spacing as fine as 4 inches (as shown) is eminently practical.
  • They eliminate T-track fastener pull-out concerns.
  • With no T-track intersection kits to install, build time is much faster.

To put some numbers to this, consider that the 3' x 2' worktop shown here has 40 slot intersections.  To build an equivalent table with hardware from Rockler, for example, the T-track intersection kits alone would cost about $1,000.  With four segments per kit, that's a total of 160 T-track segments.  For each of those, you'd have to trim an inch off the outboard end and re-drill one of the mounting holes.  Finally, you'd have to mount all 160 of those segments, using a total of 320 wood screws!  Now consider that each intersection segment would be mounted with only two #6 wood screws -- a pull-out problem just waiting to happen.

A more practical T-track grid implementation would use a considerably coarser 6" grid spacing, to match the size of standard intersection kits.  With the outermost slots positioned 3" from the edges of a 3' x 2' worktop, it would have six longitudinal slots and four lateral slots, for a total of 24 intersection kits segments.  The total intersection-kit cost is now about $600.  You still have to install 96 T-track segments using a total of 192 mounting screws, and the pull-out strength is no better.

Bottom line: A WoodAnchor starter kit will more than pay for itself in just one fixturing grid worktop, and it will eliminate pull-out worries as well.

Summary build notes

For good worktop stiffness, we recommend making your tops at least 1-1/2" thick.  The worktop shown is built of Baltic Birch plywood, and uses torsion-box construction to save weight.  The top skin and the internal stringers are 3/4" thick, and the bottom skin is 1/4" thick.  The fixturing grid itself can only be as accurate as the two adjacent reference edges of the worktop, so if you plan to use the grid for angular alignment, be sure to trim those edges precisely to 90° before milling the fixturing slots.

A portable WoodAnchor fixturing grid worktop, mounted on a DeWalt DWX725B stand

Accurately routing all those fixturing slots may look like a daunting task.  But with the aid of a simple router-base jig, it's actually pretty easy.  You can make a WoodAnchor Router Slotting Guide from a couple of scraps of material and two sliding nuts.  Or if you prefer, you can use a commercial jig such as the Rockler Indexing Dado Jig.  Both designs have an adjustable guide bar/fence that you set to your desired slot spacing.

The first step is to mill rectangular-profile starter slots in the worktop.  If using the WoodAnchor router slotting guide, you'll need to mill the starter slots with a 1/2" diameter router bit.  As usual, you should mill cross-grain first, and then long-grain. 

To machine the first starter slot in a given direction, run the guide bar against a reference edge of the worktop, just as if using an ordinary router edge guide.  For the rest of the slots in that direction, run the guide bar in the previous slot you milled, like a miter bar.  For the worktop shown, each 3/8" deep starter slot was milled in three passes with a 1/2" straight bit.

Lastly, change over to the WoodAnchor fixturing-slot bit.  Repeat the milling process in reverse order, so that the guide bar is always riding in virgin starter slots.  Total milling time for the worktop shown was about an hour.  If using a good spiral bit, you may be able to save even more time by milling the starter slots in just one or two passes.