Thread: liegh D1600 and chipout

Originally Posted by mat

Is that where you are getting the tear out?

pretty much yes - worse at the bottom and its tearing splinters that will go to the top of the cut

IME, Leigh's cutters are of good quality. The backer board must cover the entire height of the cut, otherwise you can get problems. I still suspect that the backer is not clamped close enough, or tightly enough. You need to break through on the left-hand side of the cut (when viewed from the front), then complete it by moving the router to your right. There should be videos of this somewhere, but I'm in a bit of a rush right now.

Ray.

Originally Posted by old_picker

pretty much yes - worse at the bottom and its tearing splinters that will go to the top of the cut

Hey Old Picker,

The problem appears to be that the backer board is thinner then the depth of the dovetail, use at least a backer board the same thickness. Also make sure that the backer board covers then entire cut when your are setting the jig up - raise the fingers if necessary (this should become obvious when you fit the thicker backing board.

Also as others have mentioned, use the backer board once then trim it flush with your tablesaw/dropsaw/handsaw to make expose a nice flat face again before doing another cut.

The only other thing I can think of is drop the speed of your bit down a bit and move a little slower, this can also help.

Ciao,

M.

Just to add a little confusion. I don't find it necessary to have a new backing board for each cut. Once the first one is made you have created a zero clearance backer. This provides sufficient support for subsequent cuts. Anyway, works for me.

Following on from what bob just posted, it also cuts down on wear on your dovetail bit.

I confer with Bob and Rattrap. A new backer is only required when changes are made to the spacing, depth etc.
Les

I have had the same problem with some timbers.

All the advice given should minimise your problem.

I prefer mdf as a backing boards because it gives a neat cut. That should give good support all around the dovetail.

I probably over tighten everything and even add extra clamps on tough pieces of timber. Router dovetails is an aggressive cut and I have managed to get the board to move slightly. It doesn't make a nice joint!!

My preference is to use the variable speed router and back it off a setting. Then take the cut steadily and let the cutter do the work.

I like the 8mm Leigh cutters. The quality seems good to me.

On a piece of really dry and cracked Zebrano, I added a board to the front as well as the back for extra support. It worked well. I had minimal chipping on either side of the cut.

When cutting out dovetails & finger joints i like to, where practical, hog out the bulk of the material on the tablesaw before i cut with the router bit. Takes so much pressure off the router bit especally dovetail bits giving u a cleaner cut with much less chance the bit will push the timber around as u cut.