spruce, willow or mahogany blocks?

[austin]

I am wondering if spruce or willow will work for my f5 #2 blocks. The first I built was a kit with mahogany blocks and I am going completely from scratch on this one. I am using willow blocks in a violin I am building, but am not confident that willow will hold a dovetail joint without splitting. Would spruce split in a dovetail? If not, what grain angle should I use? Should I just order some mahogany?

Thanks,
Austin

Ps, Bruce if you happen to read this, the maple for the violin back is absolutely stunning! Thanks!

[sunburst]

Any of those will work.
It depends on the particular piece of wood how easy it is to split.
It's not a bad idea to split a scrap of the wood you're using to see what you have. I've had Mahogany that split real easy and spruce that didn't. I haven't used much willow, but am familiar with it's prefered status among violin builders owing to Stradivari.
Mahogany is the heaviest of those three (usually), and that is the main reason I don't use it.
You might also consider basswood.

The grain direction in the head block is usually oriented so that the thin part of the block heading up into the scroll has straight grain runnung through it, but the head block failures I've seen have been splits from the corner of the dovetail toward the scroll, so straight across might be as good or better.