Trend Combination Router Base

A Jig for All Reasons

In the UK and, increasingly further afield, the Trend name is associated with routers, routing and cutting products. Trend has a very successful history of developing and marketing innovative products that can help consumers make the best of that versatile, can’t-do-without power tool, whether they are trade or DIY users. From my experience, the Trend router products seem to be developed by people who really know about routers and routing and the kind of problems that router users need to solve on a daily basis. Hence when I was given the Combination Router Base to try out, I immediately thought how I could use it to improve my routers and routing.

The problem that I, and most other regular router users, have is that sometimes the standard router base is not big or stable enough to achieve more than straightforward bearing-guided routing to an edge or round a template. The thinking behind the Combination Router Base (CRB) seems to be that a bigger base with trammel bars down which the router can be slid and fixed and micro-adjusted can be much more useful when doing a range of common routing tasks like edge trimming or cutting grooves.
The base is 285mm long and 165mm wide and made from solid, shiny acrylic plastic resin. At one end is an alloy extrusion called a bridge that holds the two trammel bars. The trammel bars are widely adjustable within the bridge since one of the bars is fixed and micro-adjustable for moving the router base. The other bar is able to slide in a wide groove with about 55mm of adjustable space, so it should be able to fit most commercially available routers. Once the correct distance to the router base trammel holes has been established, this bar is tightened with a spanner so that the router can now slide safely and accurately up and down the trammel bars.
The base of the router should rest on the CRB flat, so Trend has helpfully included a pack of shims of varying thicknesses. These can be fitted under the bridge to raise it to accommodate thicker bases by simply unscrewing the two screws that hold the bridge to the base and inserting the correct combination of shims.
Once the router has been attached to the base you can start doing a few jobs. One of the simplest is just using the CRB as an offset base when routing edges. A bearing-guided cutter is used to run along the edge, but the advantage for the user is that the base has a greater area and therefore will sit flatter on the top surface of the material being edge-routed. The user can attach the round offset handle on the inner side of the base and this is used to apply pressure on the base to keep it flat. This pressure resists the tendency of the router cutter to climb a little (especially in end grain) and therefore not give a full profile on the edge.
Cutting small radius circles with a router can be a dangerous business and most of the time I have tried to do it freehand with predictably inaccurate results. But with a small straight cutter fitted, and using one of two holes predrilled in the base and the pivot pin, it is possible to make circles as small as small as 19mm in radius or as big as 224mm in radius with the CRB. Attached by a strong magnet in a hole in the bridge, the pivot pin is screwed into the base where appropriate to the size of hole needed. The brass barrel of the pin is unscrewed to fit it to the base and then re-attached to fit into the 6mm hole that is predrilled to form the centre of the circle. The router base is then slid up or down the trammel bars to the outer radius of the desired circle and then tightened in place. All that needs to be done then is to move the router round the pin with the cutter whirling and the circle is done.
I found this function of the CRB a really useful one because it improves safety and convenience when doing quite a fiddly job, and the result is easier too, because the bigger base makes for a more stable routing operation.
Just like edge routing, cutting grooves against a straight edge is usually straightforward as long as the workpiece is big enough. Recently I have been making a series of garden benches where the legs run in grooves across the grain of the top. By using the CRB’s wider base and a straightedge I was able to get a much more accurate result by avoiding tipping towards the end of the cut. Since the router is easily adjustable on the trammel bars I was also able to get a very accurate slot that was a hard push fit on the legs.
If the base overhangs the workpiece Trend has provided a round-headed pin that fits into the hole in the bridge. This pin is adjusted to the height of the work so that the pin runs on the bench surface below and stops the router from tipping out of the cut.
There are a couple of other functions that the CRB has, for example copying grooves by adding a groove follower to the base and using a Trend Varijig frame to cut panels, but the function I really liked was the offset mortising feature. By attaching two mortise “pillars” to project below the base it is possible to run these two pillars against the opposite edges of a door for example, to create a mortise in a table leg. Because the router can be adjusted up and down the trammel bars, the possibility exists to do offset mortising easily.
One good idea leads to others, and Trend has already made a few other accessories available to increase the versatility of the CRB still further. In my view, this base will make life easier for router users by increasing accuracy and by easier handling and adjustability. Available at your nearest Trend Routing Centre – get online and find one!