Best way to radius corners?

[Osirus23]

What method do you use to round off the corners on your cabinets where the T-molding will go over? Right now I can only think of Jigsawing them but I know I could never get them nice and even with a jigsaw...

[bfauska]

I think the best way may be to make or find something with the curve that you want and use it as a guide for a router with a flush trim bit.

[ScottS]

Find a bottle or can with the radius you need. Put it on top of your wood near the corner and draw a line around the bottom with a pencil. Take your jigsaw and cut off the wood outside the line but don't cut too close to the line! Once you're done with this, it's likely that your cut will be slightly ragged. Wrap some sandpaper around a block of wood and sand until you're just touching the line. Try to keep the sanding block square to the edge being sanded. Go slowly, checking your work often.

If you have many corners to do, use the technique I've described to create a template out of 1/4" plywood (or something similar). Then use this template as a guide to cut the corners with your router.

If you have a stationary belt, disk, or oscillating spindle sander you could use it to do the sanding and be sure that you're getting a 90-degree edge.

[NiteWalker]

^ The way to go.

[CoryC]

Agree with ScottS!

I used tuna cans (or whatever size round thing you need) to draw the curve tangent to the 2 straight edges.  Carefully jigsaw that curve and sand away any imperfections.

[Tahnok]

It's really not hard to properly figure things out. Here's a little sketch of how to get the proper radius curve to line up with the edges. It's something that most can probably figure out on their own, but...

Step by step:

The black lines are the ones you're trying to curve.

Make two lines (the red lines) perpendicular to each edge, as long as the radius of the curve.

Connect these with a faint line (the blue lines).

Where these two lines meet is the center of the circle.

Using some sort of arc tool put down your curve from that center.

Most curves can follow that example, though inward curves can be a little harder.

[ChadTower]

That's the better method if you're not looking for a perfect circle.

[bfauska]

That's the better method if you're not looking for a perfect circle.

The technique that Tahnok describes gives you a portion of a perfect circle, and it ends where it is perfectly tangent to the lines.  That's THE way to figure out a radius corner, provided that the "arc tool" is a compass.

[patrickl]

That tangent trick is pretty clever.

[fjl]

I think I would rather use a template out of scrap wood. Use a core drill bit to make the circle on the scrap wood, then a circular saw to cut angle piece to a correct size on your cabinet. You'll basically end up with an inverted Pac-Man figure. Use clamps to hold the piece then use a flush trim bit with your router. Haven't actually tried this but sounds like it should work...

[NiteWalker]

While the method Tahnook gives is the most precise, I also prefer the method of making a template.You don't have to follow a formula; just go with whatever looks nice to you. Constantly following formulas removes the "crafts" from craftsman.

[ChadTower]

IMO, it makes the craftsman that much more versatile.  It's not removing anything, it's adding control.  This gives the ability to make really elaborate multicurve structures with precision.