I think your forestay would be neither use nor ornament, frankly.  If you sheet in the sail before you go onto the foredeck, you can hold on to the front of the sail, or the parrels if you go down the (usually) starboard side.

Hi Guy

70g/sqm  sounds light, but it depends of what the material consists of. I would have done this test: Make a cut in the cloth and then try to grab the edges of the hole with both hands and  rip it. If it is hard to rip it, then I may give it a shot. Just remember to make the edges strong (proper boltrope from rope or webbing).

However, you will spend 40 - 50hrs on the job. Are you sure it will not be an idea to go for a better canvas which will last for some years?

Anyway, good luck!

Arne

                                                                  Stavanger, Tuesday

The gaff cat rig with such a long boom puts a hard bending moment on the mast when fully close-hauled. This is because the only way to control (reduce) the twist is to use a sheet traveller and harden in the sheet. By using a fore-stay one may save an inch or two on the mast’s diameter.

I cannot prove it, but I am almost certain that the junkrig stresses the mast less hard in the same conditions so will not need the forestay. BTW, what is the present mast diameter and the displacement of you catboat?

The best would have been to make a new mast (later, when you have found that you like the rig). This mast can be given a straight conical taper and thus save topweight.

Good luck!

Arne

Guy Marlow wrote:1.I want to move the CE a foot or so forward of the CLR to combat the current weather helm.

Guy, I am not a designer, but I've done quite a few miles under junk rig.  I could be wrong, but I think you will find that a junk sail on your existing mast should work well.  Not only does the sail have balance, but its ease of reefing makes it easy to keep the helm to a minimum.

The biggest mistake that most newcomers to junk rig make, is to reef too late, particularly going downwind.  With an essentially unstayed, gaff rig, you will be used to good performance off the wind, but because of your reefing issues, will have had to cope with a lot of weather helm.  With junk rig, you can reef right down and still find the boat doing nearly hull speed.  nearly everyone who has complained about their weather helm with junk rig, downwind, has found that early reefing eliminates it.

5.I want to reduce the sail area to about 300sqft from the current 370 for a quieter life.

The sail's good manners mean that this is unnecessary and you might appreciate the extra area in light airs: however, reducing the sail area might help with points 2, 3 and 4.

 it seems that I will need to remove the currently fitted forestay ( see plan in illustrations section) . I am confident of the build strength of the mast and partners but if anyone knows of a discussion on the role of such forestays , I would be interested in reading up.