Horizontal Router Table
Wednesday 01 October 2008
Ron Fox makes this handy workshop projectfreestanding rack, and asked exactly how he'd go about making one. Ron Fox is no stranger to the subject and talks through the creation of his own homemade one for his Trend T5 router. Don't panic: it's a straightforward task, but it does involve several useful routing techniques, which some readers may not be familiar with.
As a quick note, although in horizontal mode the fence acts as the tabletop and the table becomes the fence, Ron refers to the main board as the table and the right angled construction as the fence.
We shall leave you in Ron's capable hands...
BasicsMost of the parts of the table are made in 18mm MDF, but good quality plywood can also be used.
The important thing is that this table is essentially for small and medium routers. Larger, heavier routers would need some kind of supporting strut to prevent their weight causing the mounting board to sag or bow. My own table was built with a few extra considerations, which you may want to implement yourself.
The router used is the Trend T5. The T5 has a slightly longer base than some routers, so the recess in the main board must also be slightly longer. Depending on the router you're using, you'll have to adjust for size accordingly. The cutter aperture is enlarged to 30mm. This allows small moulding profiles, such as those found in the average box of budget cutters, to be used with the table in the orthodox vertical position. The fence is made with a 30mm gap to match the cutter aperture and fitted with a dust extractor take-off point.
Mounting the routerThe router is mounted in a 9mm (11/32in) deep recess cut in the main board. Despite being a very useful skill, the technique of cutting a recess to exactly match a given shape is not that widely known.
The templateThe first thing to do is to make a template to give exactly the right recess. This should be cut with a guide bush and cutter of appropriate size.
1 Begin by taking your router base pattern, which as I have said on a number of occasions, is one of the most simple but effective work aids you can make for your router. If you have not yet made one, now is the time to do so.
2 Now, take a piece of 6mm or 9mm MDF - I use 9mm for most of my templates - and attach it to the router base pattern using double-sided tape. Place a piece of the tape on the bottom surface of the MDF, underneath where the base pattern goes. This will stop the waste piece jumping about as you cut right through the MDF. This job is conveniently done on a large board before cutting to size. This makes clamping easier.
3 With a small diameter guide bush and a narrow cutter in your router, cut very carefully round the base pattern in an anti-clockwise direction and proceed in shallow steps until you have cut right through the MDF. For this operation I use a 12mm guide bush and 1/2in straight cutter.
4 Cutting round the base pattern calls for a steady hand because if you run away from its edge, you will be cutting into the workpiece, not the waste. If you make a mistake, however, do not throw the workpiece away in disgust. Quite large bites out of the template can be repaired with plastic padding or resin-based wood filler. This job definitely calls for dust extraction fitted to the router, face mask on, and any other suitable equipment to reduce the dust nuisance.
5 The resulting template will be the same shape as the base pattern but bigger all round by an amount depending on the combination of guide bush and cutter used.
Step two - cutting the board6 Now cut the main board to size, clamp it to your cutting table and position the template. If you use the same guide bush and cutter that you used to cut the template, the recess will end up bigger than the base pattern by the diameter of the cutter. Try this on some scraps to see for yourself. You need to follow the template but push the cut further away from its edge. This is best done by fitting a larger guide bush. The offset with the 12mm guide bush and a 1/4in cutter is approximately 6mm (1/4in).
7 In order to push the cut the width of the cutter away from the template, you need a combination that gives an offset of about 12mm (1/2in). We can obtain this by simply changing the guide bush from 12 to 24mm, leaving our 1/4in cutter in place.
8 Other combinations of guide bush and cutter will also give the required result, and suitable combinations can be calculated or looked up in the very useful table of guide bush/cutter offsets in the Trend routing catalogue.
9 With the router fitted with the 24mm guide bush and 1/4in cutter, cut round the inside of the template in a clockwise direction. It should take two or three shallow passes until you reach the required depth of 9mm (11/32in).
10 This is one situation where dust extraction with a hand-held router is efficient. If you make two circuits for each pass you will find that the second circuit effectively picks up the dust created in the first.
If this is all new to you, practice on some scrap material. Once you have grasped the principle you will have acquired an extremely useful routing technique.
Step three - cutting the recess[/sh]
11 Having now cut the perimeter of the recess, the next stage is to take out the centre to get a perfectly flat bottom. You could use the router to traverse the recess, but with MDF this would create lots of dust. A much easier and healthier way is to hack out most of the material with a chisel. The MDF will de-laminate like cardboard, leaving only a small amount to finish with the router.
12 With the bulk of the MDF removed, the bottom of the recess is flattened with the router. You will get a cleaner cut if you fit a larger cutter than the 1/4in straight. I used a 1/2in straight with a good bottom cut.
I also used the Trend clear plastic offset base, which supported the router across the recess and allowed me to see where I was cutting. In addition to this I fitted a fine height adjuster to the router to give precise depth of recess. An offset base like the Trend version could very easily be made in Perspex.
13 Having cut the recess, the base pattern should be taped into it and used as a template to drill the fixing holes for the router. These are then countersunk from the front and the router fastened in the recess. A 1/4in straight cutter is then plunged through the recess to give the centre of the cutter aperture. If you are making the table for jointing, you may only require a cutter aperture of 20mm (25/32in) or so. If you have a straight cutter of the required diameter, you can fit this to your router and plunge it to give your cutter aperture.
14 In the present case I wanted a 30mm (1 1/8in) cutter aperture, so after plunging the 1/4in centre hole, I used my small circle cutter - shown several times in previous articles - to cut it. You could also use an appropriate hole saw. If using the small circle cutter, tape a piece of 9mm MDF in the 9mm recess to give a clean cut.
Bracing the table15 The MDF tabletop is braced with two stiffening pieces - also of 18mm MDF - set in housings cut in the rear. For this job I used another of my simple work aids - a piece of MDF with a slot cut in it to provide a snug fit to a guide bush. The one I used was made to take a 30mm guide bush, but if used with smaller diameter bushes, it becomes a template and straight cutters produce housings wider than their diameter. A 24mm guide bush with a 1/2in cutter gave me just the right width of housing.
16 The two stiffening struts should be cut, shaped with a disc or bobbin sander if desired, and then glued and screwed in the housings after cutting the arc for adjusting the fence. A length of softwood glued between the struts provides a solid block for clamping in a bench vice or Superjaws.
The fence17 The fence is made from two boards which are glued together at right angles with a central aperture to match the cutter aperture and provide dust-extraction take-off. The only critical feature is that the front edge of the fence should be exactly parallel to the vertical board - this is to ensure that the sliding sleds that carry the work run accurately.
18 Join the two boards with biscuits. If you have a biscuit jointer you should obviously use it, although it isn't essential. You don't even need a router table, although this makes biscuiting with the router easier than by hand. If you are biscuiting with a hand-held router, the slots in the edge of the first board are cut with a 4mm slotter and the corresponding slots in the second board with a 4mm straight cutter and your router side fence.
19 If you have no biscuiting equipment, the joint can be a simple rebated butt joint. The cutter aperture is cut in both boards before gluing them together and the fence is then braced with two right-angled pieces.
20 A dust extractor take-off point can be made if desired. The hole for the extractor hose is cut with a hole saw or the small circle cutter. The extractor point is a good application for a hot-melt glue gun, because the hot glue not only holds the pieces together but also very effectively seals all gaps.
21 The fence is adjusted for depth of cut by pivoting it at one end and cutting an arc to hold it at the required position. I used 8 x 50mm coach bolts and wing nuts that I obtained very cheaply from my local timber merchant. Drill the pivot holes in the fence and then the tabletop, and use a simple homemade trammel bar pivoting on the shank of an 8mm (5/16in) twist drill to cut the arc.
22 When finished, leave the trammel bar on the router to drill the hole at the other end of the fence. This ensures exact registration of the arc and the fence hole.
Workpiece sleds23 For cuts such as tenons and dovetailed shelf-ends, a few very simple work-carriers can be made. These consist of nothing more than a piece of MDF with a bit of batten glued under the front edge. This enables the sled to run along the fence when making the cut.
24 Be aware that the sleds are initialised by cutting a rebate in their upper surface. This involves making the cut with the rotation of the cutter. Be very careful with this cut and hold on to the sled tightly. Through not concentrating hard enough, I broke a
good spiral cutter when the sled was pulled out of my hands by the rotation of the cutter.