by Dusty82 » Fri Nov 19, 2010 3:04 pm
You can get surprisingly good results with an inexpensive router if you pay close attention to the set up and rout the material slowly. I worked with a pair of $45 Black & Decker cheapies for about 12 years, when Santa finally graced me with my Porter Cable.
I'd avoid a trimming router for cutting into 3/4 inch material - it just wasn't made for material that heavy. It would be fine for rounding over, chamfering, or other small edge treatments, but not cutting all the way through. Trimming routers are designed for softer, thinner materials like countertop laminate, veneer, and in some cases, drywall. I think you'd be sorely disappointed trying to cut through 3/4 inch plywood with one.
Better to spend that money on a good quality 1/4 inch flush trim bit. If it were me, I'd look for a top bearing, carbide tipped 1/4 inch flush trim bit - they come in cutting lengths as long as 1 1/2 inches. For the occasional home user, bits made by Freud or Bosch will do quite nicely - expect to pay $20-$30 for the bit.
I'd make a template in the shape of your opening for the top mounted guide bearing to ride against and rout the opening in three passes - cutting 1/4 inch deep with each pass. That'll help eliminate burning the bit and the plywood. Hogging out 3/4 inch of material in one pass puts a lot of strain on the router and the bit, and I personally don't do it with anything less than a 3hp router.
Get a good quality bit, take your time with the set up, and rout slowly and you should be just fine with the router you have.
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