Making band saw puzzle box--which blade is best?

First I want to thank all the great LJs who have answered my questions previously. This is a great site. I greatly appreciate the tips I have received. Without exception they have worked for me every time.

I want to make a band saw puzzle box for a Christmas present. This involves cutting a “key” into a 4×4 x 6 inch wood block. I am using walnut. On my trial runs with scrap wood my results are that the blade seems to wander. I am sure this is operator error.

My questions are: Should I guide the wood slower? I am quite adept at cutting curves with a bandsaw on thinner wood, say up to 1 1/2 to 2 inches. Also, what blade would be the best for this project?

Thanks again for your help in the past and in advance for good advice.

Source: http://lumberjocks.com/topics/22191

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