Laser cut veneer for panels, methods and ideas

So I'm always looking at various stained glass and tile patterns for ideas.
This time I decided to try a Motawi tile pattern to see about how hard it is to generate a pattern and then what veneers will work to get the design to a point it "looks nice".

Step one, grab the best image I can find of a tile pattern

It has potential, so to create a pattern I turn it into a black/white image with high contrast so I can trace it in Lightburn, software for lasers.

Easy enough, this gets me the pattern I want with "closed shapes" to represent each object in the tile design.

It did take a bit of editing to clean up the lines, but that went well. Now I can reshape it to any dimensions I need,
Next is to separate out objects into layers, one for each color (veneer species) I plan on trying.

Four colors including the background.

To make the cuts, I can just switch a layer on/off, put the material in the laser frame and go for it.

FIrst I need to prepare a work surface for all this. It's going to be about 4" x 7". I get a scrap of melamine slightly bigger and some Wally World shelf paper. The melamine will act as one of the cauls used to press everything when I glue it up

The shelf paper is taped down, sticky side up. I heat it slightly with a hair dryer to get it to expand, tape all sides to remove wrinkles, and it tightens up nicely as it cools.

Now to cut out the first veneer bit, the background. I chose some mystery wood that might look good.

More melamine scraps are used to raise the veneer sheet up off the laser bed. This keeps the backside from burning due to heat/light reflections.

Veneer in place...

...and cutting begins

Since I don't care about the cut out parts, I use enough power so they drop clear. Last part of the cut frees a 4"x7" rectangle from the sheet.

This is then applied to the shelf paper. The exposed side of the pattern will be down against the paper so this is like working from the inside.

In this case, I don't really care about having a mirror image.
Next is to cut out the pieces that are used to fill the spaces, For a good fit, I need to compensate for the laser kerf, basically make the inset pieces slightly bigger.
How much bigger?

I'll drop in one of the pieces from the background and scribe a line to measure from.

The witdh of the hole is part is measured with calipers where the lines meet the edge. This is subtracted from the width of the leaf at the line ends, divided by 2, and used as the lasers "kerf offset". 0.005" in this case.
Some woods burn easier and will leave a wider kerf, some don't. Usually a bit of trial and error.
I am using some light wood for the next set of parts. One consideration for which side to be against the shelf paper is the back side from the laser tends to have a cleaner edge.

Lasers facing side (up)

Laser back side (down on the laser bed)

If you look closely, you can see the "tabs". Small uncut areas that keep these fragile parts from detaching while cutting and getting burned up by the laser.

I place these tabs on long-grain sides since they are easy to hand cut along the grain. On the end grain they can leave a sliver that woudl need to be sanded off. (red spots are where the tabs are left)

With small parts, I mark which side will be facing me during assembly and also mark the position in case they get jumbled up.

These parts are going to be dyed.
I use TransTint and soak the parts in a bowl. This bowl is place in my vacuum pot for about an hour, then left at atmospheric pressure for another few more hours. Putting them into a pressure pot overnight will get near 100% color through the wood. This shorter process does "ok" for testing, but care must be taken to not sand too much

Usually one would dye the whole veneer piece before cutting, but that would not lay flat in my bowl/vacuum pot so I dyed after cutting.
Here are all the parts after removal from the dye and having been stuffed between some paper towels to dry overnight,

It's kind of fun placing all the parts, a sharp Exacto blade and pointy tweezers are a must for placing and moving into position.
The shelf paper will hold things in place, but they can be lifted and reposition if needed.

All placed and ready for the vacuum bag.

I get a 1/4" piece of BB plywood and a piece of veneer for the back side so the panel layers will be balanced.

Not shown here because I like to work fast to get everything glued up and into my vacuum bag.
Basically:
Cover a second caul with a paper towel.
Roll on some veneer glue to one side of the plywood, lay on the backing veneed, and set this side down onto the caul.
Roll on glue to the other side of the plywood as it sits and position and place the panel o' bits on top.

I now have a sammich, top/bottom cauls, front/back veneer, and plywood which goes into the vacuum bag for 2 hours.

 

Out of the bag, back caul removed exposing the back side veneer.

I also cut the masking tape holding the shelf paper in place so the other caul can come off.

All that is left is to peel off the shelf paper.

Some sanding and a wipe of mineral spirits to check the colors.

You can see where the light green sanded away more in spots, should have left in in the dye longer.

The fit of the parts isn't too bad.

Not sure what I'll do with this but certainly would try adjusting the color scheme next time.