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Does if make a difference which one comes up first, getting ready to do high speed motoring? I don't do this often, but for season end outing last week end, I was planning on getting some speed. after leaving the no-wake zone protected by breakwater, I slowed to nearly stop, then raised the ctr bd. Before I could get to the rudders to raise, boat started to rock quite strong. I immediately let the ctr bd down again & the rocking stopped. Is that the waves working the rudders, or loss of stabilizing effect from the ctr bd? weather was not too bad. usual 6ft swells were not present. maybe 3 ft wind waves. mild wind, although gusty, chnaging directions.
OR, was I imagining things??
RHC

I would guess that you slowed nearly to a stop would allow the waves to adversely affect the rocking motion of your sailboat. The sooner you get moving with some speed, the easier the boat could handle the larger waves.

Phil M

I don't have the same sailing conditions in the Chesapeake Bay as you have in California ... that being said, you might raise the centerboard to about 2/3 - 3/4 up, and see if that keeps the hull stable enough, then raise the rudders just part way up - so they'll come up easily when you put on some power. Bring speed up to 5 kts or so - enough to get good directional control from the engine - then raise rudders all the way, pull up the rest of the centerboard, and now pour on the coals.

I would never raise the rudders part-way, even for a few moments. All the way down, or quickly all the way up, otherwise you are putting alot of stress on the steering gear, rudder pintles, rudders, transom etc. They are not designed to be used in any other position than all the way down, or raised out of the way.

To convert the boat for fast motoring from the sailing or slow motoring set-up, just raise the rudders first, which lets the motor and the centerboard do the steering, then lift the centerboard while still going slow, before the forces gain on it and make it impossible to move.

Ditto that post above.

You can change the moment (the distance from the pivot to the centre of action of the rudder) by more than 10x with 'partial rudder deployment'

This is really, really bad for your linkage and steering gear and you will break something expensive.