Gunter Rig Mystery

[Pompey]

Can anyone help me understand the rig on my new boat. It is tricky to describe and I am hopeful that someone with a similar rig may understand it. Having recently bought a trailer-sailer which had a bermuda and gunter rig, I found it was originally a gunter rig which had been converted to a bermuda - and the original gunter spars, without rigging are present. I would like to convert it back to a gunter and need to designe the masthead block arrangement. My dilema is, the gunter spar has a sliding bar about 36inches long, where the top halyard would be connected. This means when the sail is hoisted, the gunter will only be raised until the top of the slider is level with the top block on the main mast. To hoist the sail the last 36inches, I will require another block on the mast to raise the gunter-jaw, thus pulling the gunter along the slider the last 36inches. I don't understand the purpose of the slider? Why would you not simply have a fixed shackle on the gunter spar 36inches lower, (i.e. bottom of slider) and hoist the sail in one go? Does that make sense? Can anyone explain the purpose of the slider?
Thanks

[Steve Bailey]

Is it perhaps a way of keeping the gaff tight up to the mast whilst reefing the sail? If the gaff is "top heavy" when fully hoisted it will fly about in the wind when you slacken the halliard to reef the sail, without some means of restraint, which I beleive your slider bar may be.

[BHOFM]

I would love to see some photos of what you have as
I plan to rig my new boat with a gunter.

Check this:

http://www.boatdesign.net/forums/showthread.php?t=24381

[TeddyDiver]

Hope these helps:
http://en.wikipedia.org/wiki/Gunter
http://www.duckworksmagazine.com/04/s/articles/gunter/index.cfm

[Pompey]

Thanks for the responses. The most logical explanation is what Steve suggests and that is that the slider keeps the gunter spar tight into the mast when the gunter is lowered for reefing. - thanks Steve. Unfortunately there is no reefing ties on the mainsail sail, which looks like the original sail - maybe the reefed main was an option. As the sail shape is like a burmuda with a straight leech, it will make hoisting and lowering in any breeze a lot tidier by holding the spar close into the mast.
Regarding request from BHOFM - attached are some sail and spar pics - let me know if you would like more. For interest, Tideway Dinghies in the UK make a 12ft gunter rig, so you may get some ideas there. http://www.tidewaydinghies.co.uk/
Thanks, TeddyDiver - good references to understand the gunter rig operation.
Regards
Pompey

[BHOFM]

Pompey;

Thanks, that gives me more ideas to work with.

B