Aloft DVD
 

The DVD says that the harken block has a 2:1 advantage. BT's book in diagram 2.2 says that there is no mechanical advantage which appears to be the same lift as in the DVD.

What am I missing?

Thank you.

Not looking at the video so I may be missing what's up but if you have a single block at the top - like a halyard - with the fall attached to your harness or chair, then someone at deck hauling you up has no mechanical advantage and must lift your whole weight. If you, sitting in the chair, have the hoist in hand to pull yourself up, half your weight is in your hands while the other half is in the seat - giving you a 2:1 advantage.

Postition is everything.

G'luck

That occurred to me a couple of hours later as a possibility. Positioning indeed. So true, so true.

Thank you for replying.

It's even better
 

Hi,
And when you are hauling yourself up the front of the mast (possible if the rake isn't extreme), you can place your feet against the mast and "hip thrust" as you pull. This takes even more weight off your arms. It also puts the stress more onto your back muscles, not just the biceps.
Fair leads,
Brion Toss

Nice of you to chime in Brion. I am enjoying your DVD's (3) and books (2).

I decided to go with two Harken blocks just in case I need the mechanical advantage: a 1572 ratchet block with becket for the mast head and a 1549 ratchet block attached to my harness.

The blocks are rated for 9/16's maximum diameter line. In the DVD the rope you are using to haul yourself up appears to be quite thick, perhaps one inch and easy to grip. What size is it?

Fair vines.

Tarzan

Options
 

Hi again,
That's 5/8" Regatta Braid, which feels nice and fat, stows (not coils) nicely in my line bag, and fit's well in those Harken blocks.
Note that, with two ratcheting blocks, plus the extra advantage, pulling yourself will be much easier, so you won't have to grip as hard, so 1/2" Regatta should be just fine. Oh, and you will probably have to turn off the ratchet on the lower block to descend -- that's how effective they are.
Fair leads,
Brion Toss

Take-a-knee
 

Insightfull & brief as always. Thank you very much.

All the best with knew knee.

Don't rush it. Do what feels right.

Tarzan