I am not accomplished on a drop spindle (used it several times), but anytime I feel less than competent I prepare the roving--breaking it into lengths, the "peeling" it, and finally flick-carding it. Makes a world of difference, even for my spinning on a wheel.
I still consider myself a beginner, and I still find working with roving a bit tricky, especially the packed-together stuff straight from the store (the twist keeps getting behind my working fiber--especially with slippery fiber that is not easy to draw out into long lengths before allowing the twist into it). I much prefer working with Romney wool carded into bats. I feel like a pro when I do that!
I'm assuming you've spun alpaca on the wheel before.
Hopefully someone who has mastered the drop spindle can help more.
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