Routers, Rabbets, Chipout

[JoeL]

I am experiencing chipout will routing 3/8" wide x 1/4" deep rabbet on some rectangular pine frames I built (rabbets are to recess plywood panels). I am using an Amana bit with a guide bearing. One way around this that I know is to run the router the "wrong" way, this works but seems a bit risky because the router does not want to pull into the wood, rather it tends to push out. I cannot use a rotuer table since the frames need to be assembled before routing. Any suggestions out there?

[ROBERT]

You make no mention of how beefy your router is or the details of your bit (other than its got a guide bearing), but it sounds to ME as you're taking to big a bite in one pass and the bit is literally "hacking" at the grain, causing very small splits.

If it's a simple point of exit blow out, a little masking tape will take care of that 95% of the time, as does running the router "backwards" to pre-plough the point of exit.

[rrich]

Joel,
From you description I don't understand the chip out. It's a frame (i.e. A closed loop so to speak.) and assembled. It seems to me that every piece is backed in some way and similar to using a sacrificial piece of stock. Also you describe the router pulling into the wood vs. pushing. Usually, the router pushes back towards the finished cut.

Based upon your description of your project, I'm assuming that these are rather large frames. If you were standing INSIDE the frame you should be moving the router Left to Right. That should smooth things out. Also if you are using the bearing as the ONLY guide you'll have difficulties. Use the edge guide that is available for your router. (s/b $20-$30) The edge guide will help a lot. As Robert suggested try several cuts to achieve the desired cut. Depending upon your router you may have to do as many as 4 passes to get to both of your depths.

Good luck and let us know how everything turns out.
Rich

[JoeL]

Robert,

You nailed the problem description, it is exit "blow out". I'll try the masking tape.

Thanks