I am using (or trying to) the glue joint bit to join maple boards to make the cutting surface of a butcher block. I've figured out how to line up the bit to get the pieces to match, but I'm getting alot of tear out as I get to the end of each piece. I have the speed set correctly (2.2 HP router), the smallest size collet ring, and the smallest fence opening. But as I pass the last 1-1/2 inches through the bit, it grabs the piece and takes a nice size chunk out. What am I doing wrong? Thanks for any tips.
-Cam M.
Havertown, PA
Our Expert
It sounds as though you're having trouble with snipe. Snipe occurs when the outfeed fence is not adequately supporting the stock.
The length of the snipe is equal to the fence opening, in this case 1-1/2".
With some types of bits, such as the Amana Tool glue joint bit #55388, if the cutting height is equal to the stock thickness the entire edge of the stock will be removed when routing. In other words, none of the original edge remains on the stock after it passes the bit. Once the stock is no longer supported by the infeed fence it drops into the spinning bit creating a heavy cut, or snipe, at the trailing end.
The key to preventing snipe is in the fence adjustment.
One method is to adjust the outfeed fence forward slightly to compensate for the loss of stock. Sh
apers are designed with a split fence for this adjustment. An micro-adjustment knob allows you to independently adjust the outfeed fence forward. However, most commercial router table fences lack this feature. Instead, the outfeed fence must be shimmed. Although this method works, it is somewhat fussy because the cutting depth must be adjusted to equal the shim thickness.
The method which I prefer is to adjust the fence tangent to the smallest cutting diameter of the bit. I position a straightedge against the bit and slide the fence forward until it touches the straightedge. This method provides you with the full shape of the profile without a loss of stock and snipe.
View illustration
