[quote=Edchris177][quote]And ideas on what this setup is for? Photo below [/quote]
I think it is for mast rotation. That was added, it was an option on the boomless boats. I removed mine on the 5.7. It helped a bit downwind, but the greatest advantage was in really light or flaky wind. You could lock the mast in one spot, rather than have it bang around & continually shake the wind out of the sail. I didn't use the turning block, just a padeye & cleat, like so;
[img]http://www.thebeachcats.com/gallery2/main.php?g2_view=core.DownloadItem&g2_itemId=74457&g2_serialNumber=7[/img]
That is an old photo, the lines are wrong. It should be a continuous line. Start with a deadend at one padeye, out to rotator, back to same side cleat, then around behind mast to opposite cleat, over to rotator, then back to opposite padeye. That gives 2:1, using a single line.
[quote]That leaves the mast base and ball to buy so not quite as bad.[/quote]
Reference above photo. If you have the small ball/DS rod, you also have a smaller V strap, along with the pad the DS rod sits in. IIRC, from an old 5.2, the smaller rod ends with a "pin" that goes into a hole in the smaller V strap, & is held by a screw.
If you elect to build a DS rod, you will probably not have success trying to turn a Harbour Freight die down that rod. Get a friendly machine shop to cut them, they will most likely do it on a lathe. There is just to much material to cut using a plain jane die. When my neighbour cut mine he said he turned the blank rod down by .001 first, it makes for easier threading of nuts.
I have a couple extra V straps & DS pad. You will have to drill a larger diameter holes for the new rod,(try to use a drill press, otherwise you have zero chance of perfect alignment of the holes) & will also need the compression tube that goes inside the beam, shown here;
[img]http://www.thebeachcats.com/gallery2/main.php?g2_view=core.DownloadItem&g2_itemId=87297&g2_serialNumber=3[/img]
Your new mast base will look like this. The big difference, besides being "captive", is you MUST rotate the mast 90*, & keep it that way while you raise or lower the mast. From the photo you can see what will happen if you drop the stick, without rotating it...you get to buy a new DS rod, & probably a another mast base.
[img]http://www.thebeachcats.com/gallery2/main.php?g2_view=core.DownloadItem&g2_itemId=76386&g2_serialNumber=6[/img]
Nacra hid serial #'s all over the place. Some were stamped in, some hand carved, some 5.0 buried them under the rear beam. The only Nacra 36 I have seen had it finely engraved on an SS plate.
Here is a thread on the subject.
[url]http://www.thebeachcats.com/index.php?module=forums&func=viewtopic&topic=14494[/url]
Try to find that #, I have seen several '83's, none had the centre bar, just the 1/2 moon chocks. I've never heard of them breaking, & those boats are now 30 yrs old. I'm thinking a PO bent a beam & changed it to beams from an early 5.2, which used a centre bar.<!-- editby --><em>Edited by Edchris177 on Oct 30, 2014 - 05:11 PM.</em><!-- end editby --> [/quote]
