Roller-Furler for the M-17
Mike Leonard (mikit@pioneer-net.com) did quite a bit of analysis before purchasing a roller-furler for his M-17 Whisper in Spring '99. Below are some of the fruits of his labor.

Reasoning and Conclusion
I selected the CDI Flexible Furler 2 unit with the bearing. We purchased it about 18 months ago online from JSI (Johnson Sails Inc.) I checked out many sources including the manufacture with JSI offering the lowest cost and free shipping. I decided on the model with the bearing and it does work well, I've had no experience with the non-bearing version for comparisons. With the bearing you do not need to use the thrust washer provided. The Furler 2 has a larger drum and is generally more stout than the Furler 1.

For the M-17 I would recommend the Furler 2 and probably the Furler 1 for an M-15. The foil was about 6 feet longer than needed and was easily trimmed to size. The only modification to the forestay was the addition of a toggle on the head as recommended by the manufacture. This was a $15.00 item from West Marine. A top of the line toggle at that price. We have used the unit one season and so far it has worked very well with no problems whatsoever. I have no idea what they are selling for now, I paid somewhere around $350. You can check out my measurements in the Montgomery owners group web page at http://msog.org [see below-webmaster].

As far as the sail goes, I solicited 8 or 10 bids with the North Sail price about in the middle of the group at $820.00. The highest was Neil Pryde at $1200.00 and the lowest was Mac Sails around $450.00. I went with North because of recommendations, reputation and some speculation. I specified ----150% All Purpose Genoa - 4.75 oz. NorDac sail cloth, UV leech and foot, Rope Reefing Pad, furling patch, and webbing attachments at the head and tack instead of grommets as recommended by CDI as well as # 6 luff tape. My preference was to have the sail furled counterclockwise and un-furled clockwise to starboard. They need to know this so the UV material is attached to the correct side. The UV material is a lightweight product as opposed to the heavier Sunbrella. I think Sunbrella UV protection would be too heavy for a sail this size. I went with their recommendation and chose the rope-reefing pad. I was told the foam leach tends to establish a set or memory in the shape of a curve after time. I don't know if this is true but I do know the rope luff works extremely well.

The sail was ordered through North Sails in Portland, OR and manufactured at the North loft in San Diego. With an LP of 9.85' the sail is not too big and tacks quite well. Two reefs are marked on the foot of the sail for 134% and 120%. In both configurations the sail has good shape and performance. The sail fits the CDI unit like a glove and that was quite a relief. If interested I could provide the sail serial #.

We are pleased with both units in both quality and performance.

Sail Plan for Roller-Furling 150% Genoa
By Mike Leonard