How do I make this cut?

[RayV]

For a project I am working on I need to use a dovetail bit to take the edge off of both sides of a thin piece of wood (1/4"). The end result needs to be a trapezoid cross section. The piece will slide inside a dovetailed groove in another piece of wood.

The problem I had was since I was taking the whole edge off the piece wanted to slide under the fence since the pointed side is down when using the bit in a table. The trailing end also got a little mangled but I expected that and made the piece longer than needed. I suppose I could have ripped the angle on the TS but the piece is only 3/4" wide so not the safest idea.

The results I got were good enough for the purpose I have in mind but not if the piece was to be visible. Best idea I can come up with for the next time I need to do this is to put a piece of hardboard down on the router table to effectively raise the table higher that the fence so the piece can't get under the fence. Anyone have a better idea?

[Lowell Holmes]

I think some sort of jig might be appropriate for use on the table saw. I can't visualize the piece your making. How long is the piece your working with?

I would probably make the bevel with a block plane and fit it to the groove.

[Swingman]

If I understand you correctly, and I'm not sure at all that I do ...

You can use the table saw safely if you cut the needed piece off a wider workpiece:

Make the first cut on the edge of the stock with the blade angled appropriately, move the fence over the appropriate distance, flip the workpiece over and make the second cut ... in this case the offcut would be the keeper.

Kindly ignore if this is not what you are trying to accomplish.

[RayV]

If you look at this sliding dovetail link the piece I needed to make was just the part that slides in the groove. The finished piece is about 15" long.

looking at the picture I suppose the next time I need to do this I would make the cuts on the end of a board and then rip the 'slide' loose from the main board. But this wouldn't help if I needed a slide

1" wide and only had 3/4" stock.

Thought about the plane but I am still learning plane skills and needed the piece to be maple so I doubt I could have done that.

[Swingman]

in my previous post using wider stock the same thickness as the depth of the groove.

Providing you have a TS with a tilting blade, there is probably no safer, easier, quicker way to do it.

[RayV]

This could work... but I have a right tilt saw so If I'm thinking this out correctly: blade angled to match groove fence to left of blade make first cut ROTATE piece 180 make second cut with fence ~3/4" from blade

I would feel safe doing this because I use a pushstick similar to this

[Swingman]

Flip the piece end to end, longways ... it will be apparent when you get ready to do the second cut. ;)

That will work. with the appropriate pushstick.

However, it would be safer (since you seem worried about safety, and rightly so!) to make the second cut 3/4" from the JUST CUT edge of the _wide_ stock ... remember your are trying to this safely, so you want as much wood between the fence and the cut as you are comfortable with.

Then flip the wide board again for the third cut, setting the blade the appropriate distance from the last cut edge, to cut the second piece.

Repeat the flip, resetting the fence for each cut, until you have all your pieces cut off the same _wide_ board.

Each time you do this the blade will get closer to the fence, so the wider the stock you start with, the more pieces you can cut in your comfort zone.

CAVEAT: You really need to measure the distance from the fence to the blade carefully because angled cuts in this manner can fool you due having "pointy" side down on the second cut on a right tilt.

That's really the only caveat.

[RayV]

Swingman patiently explained:

After coffee kicks in I finally get it. Thanks.

[Lee Gordon]

Make your first cut, then temporarily stick a line of scotch tape (or some other easily removable but slick-surfaced tape) along the intersection where your fence meets the table to keep the pointy part from sliding under. I just saw Norm use this trick this weekend.

Lee

[bsa441]

Since I assume you are making only one piece, 1/4" thick by 15" long is not much wood. Rip out several blanks, get out your plane, and start learning!

RayV wrote:

[Prometheus]

I don't know about you, but using the fence on the left side usually gives me poor results. Might be different for a left-handed fella. I'd take a piece maybe 4-5" wide, leave the fence on the right side, and make the first cut, then flip the piece end over end, adjust the fence so that the offcut was the right size for the piece I needed, and cut again. The wider stock will compensate for the right-tilt, and give you some room to get your pushstick in there.

I think this was what Swingman was describing, also. If you do it your way, there's a chance that the workpiece will ride up the fence if you apply too much lateral pressure. Doesn't mean it *will* happen, but if you're like most folks, cutting on the left side is different that your usual procedure, and that's starting to stack up too many variables for me.

[RayV]

No way I'm cutting a bevel with the fence on the right side of the blade on a piece that narrow/thin. I think that is just begging for a kickback with a right-tilt.

If I ever do upgrade my TS I will most likely get a left-tilt because of this.

[Doug Miller]

[...]

If you have a planer, you could do what I did in a similar situation: start with thicker stock. Raise the bit high enough that it doesn't cut the entire edge, mill both edges, and then plane to final thickness.

First mill this with the router: __________ / \ |__________|

Then plane til you have this: __________ /__________\

[whit3rd]

[for making a dovetail slide]

and, of course, the final cut is hard to make because the opposite surface to the final cut is already beveled and doesn't ride against the fence nicely.

My solution (there are several) would be to screw the strip to a straight board and cut it, then flip it end for end and screw it down again and cut the other edge. You could even get fancy and make a clamp with two long jaws, a few captive bolts and wing nuts, glue a spacer on one side of the line of captive bolts and clamp the workpiece on the other.

In either case, a fence in either a router table (preferred, since you have the bit that you'll make the dovetail socket with), or a table saw (icky mainly because of the difficulty of adustment/readjustment for the special cut) will ride against the suitable jig surface.