Back in the Spring we cut down a sycamore for green woodworking. And got a surprise at how difficult it was. The drawknife floated through Ash, but not this sycamore, even though the timber was less than 48 hours from cutting. Other tools - a plane for example - have done no better. By now the wood has dried out significantly so the problem is worse than at the first.
The objective is to get flat smooth pieces at least 4 inches square and ½inch thick for pyrography. Any suggestions on how to work sycamore to achieve this? Internet searches have yielded very little.