J/30 Class Association Forums J/30 Forum The Boat, Sails and Equipment Wooden blocks at the partners

Russ - I don't know if it is "good" or "bad", but do know that I center the mast before starting the adjustment of uppers and lowers. This from the UK Tuning Guide

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2) Remove partner blocks and center mast with upper shrouds. Use the main halyard to equi-distant points on either rail as a guide. Take-up on the lowers just enough to keep the lower mast in column with the top (hand tight).

3) The mast step should be maximum forward (so that the forward edge of the mast is 25mm aft of the forward vertical face of the molded step in the sole liner. Block mast in front, pushing it as far aft as possible in the partners. This will reduce prebend in the lower mast sections.

4) Adjust wooden blocks so as to fit snugly on either side of the mast partners. Shimming and/or planning may be necessary, as there is a good chance that the mast will not be perfectly centered in the partners.
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