Any tips for shou sugi ban carving?

I’m brand new to cnc carving and decided to try the Japanese style of burning the wood first (Shou Sugi Ban).

I started with planing the wood flat, torched with MAPP gas, cleaned it up with soapy water, and started carving.

At some point, the wood ended up cupping pretty bad and I ended up with the the v-bit embedding pretty deep into the top and bottom, and skimming along the middle. It was obvious what was happening right away, but I let the carve finish just to see how it’d turn out.

The enormous H ended up being a bad design decision considering the bit’s I’m using and how I built this with a vector image editor. The pattern around the H was created from a bitmap image converted to a vector … the little problems ended up being far more noticible when the carving started.

Anyhow …

There are some very nice clean edges along the top, and then things just go south towards the bottom of the board.

I really like the look and texture of the burned wood style. The carving really pops out with that black background.

I want to find a way to work with this style, but need some advice on how to overcome the challenges involved with the wood cupping like it did.

Hi @ActonGorton

You may want to watch what @WinstonMoy on Youtube did to combat this when making his coasters. He has a lot of good tips as he goes through some of the same trials and tribulations as you are going through. I think one thing that may help is to evenly weigh down your piece with something flat after you burn the surface. Another thing you might try is burning both sides evenly. Those together might help to some extent.

The trick to V-carving is that the surface needs to be flat flat flat or you’ll have the issues that you are describing.

Just as another thought. If for some reason you just aren’t able to get the surface flat enough after burning the pieces, you might try to send your g-code to the machine via a sender that can map an uneven surface. I know it can be done with ChiliPepper. You basically map the surface of the piece you are going to be carving and ChiliPepper will automatically adjust the g-code to over lay onto the mapped surface, therefore following the ups and downs of the surface you are trying to carve. Hope this helps.