Matt,

The "gaping hole" is the better solution, not just for keeping the halyard and yard deconflicted, but for mechanical strength. It, in effect, converts the entire top of the mast into the side plates for a block. With the block being an integral part of the mast, the stress transfer is about as efficient as it can be. It's smoothly distributed, it's balanced  from side to side and it's all in vertical compression. Even though it seems a large hole, it's at the part of the mast with the lowest stress so there's plenty of reserve strength.

The cheek block, on the other hand, concentrates the forces at the fasteners. The mounting position that you propose unbalances the forces so there'll be a torque trying to tear the block off the mast. You'll have to run fasteners through the mast to have any chance of it staying together.

There's also the problem of stuff sticking out on both sides. It will catch lines, sails, etc. And, of course, the halyard tangling with the yard and sail. Think of how fun that'd be if you dropped the sail to reef it and it  got jammed.

Do yourself a big favor and go with the build instructions. You'll be glad you did.

Have fun,

Laszlo

Sage advice.  I should probably think twice before posting something past 10pm ;-) 

So one follow-up then -- is there anything to do with the mast before varnish?  Would a coat of epoxy around/through the hole be worth while to reduce the chafing of the halyard?  Perhaps a bit at the step of the mast, too, to help protect the end grain?

Thanks, Laszlo.

Matt

I'd treat it just like the hull - put on enough coats of epoxy to waterproof it, sand it smooth and then apply your multiple coats of varnish to protect the epoxy.

Laszlo

On my NE Dory   I had already made the gaping hole when I decided I wanted adjustable lazy jacks, so I turned the mast a quarter turn and repurposed the gaping hole to be the new lazy jack "halyard", and I mounted a cheek block up there too...the machine screws for the halyard cheek block were on each side of the hole.   In this picture you can also see the block mounted on the spar for the halyard...between the two low-friction blocks, I can drop the sail in a nano second and it drops into the lazy jacks nicely

Here is how I organize the lines..two downhauls on port, the green on stbd is sail halyard and white to stbd is lazy jack halyard

Curt

Curt,

An alternative would be to use the hole for the main halyard as intended, and put a smaller cheek block on each side for the lazy jacks a la the Faering Cruiser. That would maintain the symmetry of forces and potentially allow 2 through bolts to be shared between the cheek blocks. This would still let the main halyard force be mostly in mast compression. The torque on the lazy jack cheek blocks is much less than the torque on a main halyard cheekblock because of the lower forces on a lazyjack.

Laszlo

   Laszlo,

 I hear your thoughts...I thought about that approach but the way I have the sail halyard rigged around the mast (to keep the boom from flying off to the next county) would cross over each other and get tangled up with the jack halyards if I used the original mast hole, you can see in the picture the cheek block is on the same side of the mast as the boom...also I did try both jack halyard lines thru the cheek block with the sail halyard in the mast hole, and there was just enough friction on the sail halyard that the sail would not drop nearly as fast as it does now using the cheek block.

Isnt rigging a sailboat the ultimate in multiple options?

Curt