Is there a practical way to cut off a piece of a live edge slab, and then seamlessly rejoin it?

Question

As mentioned in other questions I've posted, I'm building a memorial bench for my mother, who recently passed away. I would like to have some poetic stanzas inscribed on the seatback on either side, and "In memory of..." inscribed across the center of the seatback near the top. I feel that laser engraving is the best method for doing this.

I've checked in with every place I can find in my greater metro area, but all are limited to a 24" x 24" area. One offered to slide each side of the slab in to do the engraving on the sides. However, there is no practical way to engrave anything in the middle of the slab.

So I thought a solution may be found in cutting out a rectangular portion of the seat back, having it engraved, and then reattaching it and using wood fill or something similar to mask the cut marks. I've used wood fill before, and feel like even if I get the color right the straight line from the fill will cause a very visible blemish. Are there any other methods of cutting and then reattaching a piece of a slab that create a seamless result?

I will attach an engraved metal plate, or laser engraved slice of wood, if necessary. However, I feel like this works against the creative flow of the piece.

Answer 1

You may want to consider contacting the Darkly Labs people. Their Kickstarter project for the Emblaser v1 created a laser engraver and low power cutting machine that uses a flat piece of metal for the base. They may be able to give your contact information to an E1 owner in your area.

A number of Emblaser v1 owners have made this portion removable, allowing the laser to be positioned anywhere on a flat surface to engrave up to the maximum size of the device. I have an A3 (approx. 11" x 17") Emblaser v1 to which I've modified the base to be a piece of honeycomb aluminum, to increase stiffness. It is still removable and would work in your example.

There may be other laser engraver devices on the market (diode lasers, not CO2) that would operate or be modified to operate in a similar manner.

Less realistic is to consider to have a slice shaved from the surface you wish engraved. It would be possible to use a laser to cut out the section to be engraved if the slice was thin enough, then after the engraving is completed, the segment would be re-inserted in a manner similar to an inlay and the removed slice would be re-attached to the back. You'll lose kerf width when the back is sliced, but it's going to be in a less obtrusive location. The inlay could be done in an artistic manner, reducing the impact of the laser kerf as well.

Answer 2

Typical laser engraving places don't have the right equipment for this, but larger custom fabricators with large CNCs will often have a laser head that could do this. That said, it would be fairly expensive. You may prefer to buy a Shaper Origin (like a router with autopilot or autocorrect) and engrave it using a v-bit instead.