Router trouble with edge grain

[A Womack]

A buttefly jewelry box projec I have been working on since before christmas keeps getting ruined while routing different pieces. I am attempting to pattern route with a 2 flute carbide top bearing bit. I've used both a Porter Cable that I find still to be sharp (judging from digs in fingernail and the nice shavings) and a brand new Amanaa bit.

When I round the top of the wing and come along the side where the edge grain is at it's shortest, the bit rips about 1/2 off the side, thus ruining the piece completely.

I had initially posted about this when I made my pine prototype and was assured the harder purpleheart I am working would hold up. I am however, finding the opposite to be true. The Purpleheart is worse than the pine and in that 80% of the time the edge grain tears off.

Besides using a drum sander to do this part of the project, what other router techniques should I use? I have begun to consider gluing a piece of wood under that would run with end grain perpendicular to the edge grain to help support it.

Alan

[C]

I dont' understand fully what you are doing, however, never to be one without an opinion, here goes...

1. Change direction of travel. It almost sounds as though your bit is peeling away the wood. Try to visualize how the bit spins, where and how the flutes attack the wood.
2. If possible, slow down the motor as well as the speed you are moving the router across the material.
3. Use a router table for better control.

1. For problem spots, start your rout from the end and work toward the center.

2. Use a smaller bit.

[Larry C in Auburn, WA]

Sounds like you can't use a backer board which would probably eliminate the tearout. You might have to do a climb cut, but be careful it's not a very safe technique. I'd also look at Pat Warner's web site, he probably has some useful info.

[B a r r y B u r k e J r .]

Clamp a sacrificial block to the end grain. This way you're not starting or stopping on an end grain corner.

Barry

[A Womack]

C wrote in news: [e-mail]:

Indeed, this is exactly what happens. The edge grain tears away at the top of the cut as I am coming down around the edge of the wing. The Top of the wing is fine, it is where the edge grain get's short

[bstrawse]

Alan, Are you trying to cut the whole thing out with a pattern bit? Most of the time I just cut close to the shape with a band saw or jig saw and then use my pattern bit to finish it off.

[A Womack]

[e-mail] (bstrawse) wrote in news: [e-mail]:

I used my jigsaw to get close, say no more than 3/8" away anywhere around the pattern. Today I picked up a smaller pattern following bit,

1/4" variety. I think I can more easily climb routing with this bit to alleviate the tear off. I will also try hot gluing a piece of scrap at a 90 degree angle to the edge grain to give it some more support.

If that doesn't work I bought a 3/16" bandsaw blade today to try.

[Sprog]