Beatrix has a tension rod (it came with my boat) that should alleviate the upward pull of the base blocks. This is a 1/2" stainless steel rod that runs from the cabin top to the keel. In doing this task it is worth making an effort to calculate the real loads. You need to do this anyway to size the turning blocks. Most control lines are rigged with a 2:1 ratio, more for the vang. It's not as much load as you think. I think I estimated a max load of 800 pounds on any one line.The design issue is to get the line low enough so it enters the deck organizer with a fair lead. That's mostly why I chose the half-moon blocks on the deck. To fasten low down on the mast gets in the way of the mast boot, so you still need a collar on the deck. The only way I can think to alleviate upward tension is the tension rod or else some tangs that fasten the deck to the mast below. I've seen this done with small rigging turnbuckles, one on each side. That would work well. Or possibly the deck is actually strong enough to take the strain.
I used Schaeffer half-moon blocks for the mast base leads (too beefy, but I really like the looks). They are through-bolted to the inside of the cabin with SS backing plates. (get the SS from www.onlinemetals.com if finding small bits of stainless is difficult). The deck organizer is a Harken ESP in stainless, small but plenty strong, very beautiful, unobtrusive. So far I have left the reefing on the mast. This is standard jiffy reefing. To bring reefing to the cockpit double-line reefing works well but requires FIVE lines including the halyard. That is for two reefs. Not a problem since my main only has two reefs, but I can't imagine bring three reefs to the cabin in any event. I would still recommend leaving the main halyard winch in place in any case.
The normal single line system has too much friction in it. I've never met anyone that found ordinary single line reefing very well, but you never know. Only Selden Masts has a single-line reefing system that I know works well. They use internal sliding blocks to even out the tension. You have to buy a new boom($2400 or so, probably more now that the dollar has tanked). Bob Hawk and I think we can retrofit our existing booms to use a selden-type system for about 25% of the cost of the new boom. If we get a design for this and if I decide to do it I'll post it here.
Even with single line reefing you now have FOUR control lines (cuni, downhaul, outhaul, vang) plus THREE reef lines (halyard, reef1, reef2). On my boat the cockpit cabin top has my radar display to starboard, so there is no room for a second winch. The four control lines I now have are run to a single Harken 32 ST winch on the port side of the companionway. The main halyard comes down the starboard side of the mast. I have thought of running the halyward down the side of the cabin to a Spinlock on the coaming and then use the secondary winch to adjust it. If I were flying the staysail on port tack this would mean letting that fly while I reefed or tying it off with a rolling hitch or maybe having TWO spinlocks. It gets complicated. But I've thought that the coaming idea had some promise. What I intend to do, if I proceed with the single-line reefing idea (which I may not - I'm keen to get out of here and just keep reefing on deck like everyone has been doing for years) is to have either six or seven lines to the one winch on the port side - not ideal, but what the heck.
These photos and plans are available for download:
Control lines (smaller images) (ZIP File, 257.6 KB)
Control lines (larger images) (ZIP File, 1 MB)