Typhoon Rigging Question

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jamie harrell
Posts: 7
Joined: Sep 16th, '05, 10:34
Location: Typhoon #941
"Osprey"
Mobjack Bay VA

Typhoon Rigging Question

Post by jamie harrell »

This season we got a 5hp motor and mounted it on the original o/b bracket. I've noticed we're a little stern heavy and have been meaning to add some weight to the bow so it will sit a little flatter on her mooring. We sailed this weekend and I noticed that the backstay tension was significantly loose while on our mooring. Could the extra weight of the motor be causing this due to it not sitting flat? I need to tighten it up but I wanted to check with others. I've owned the boat about 2 1/2 years and have never really adjusted any of the standing rigging. I've got the closed barrel turnbuckles and from the listserve think I understand how to adjust them.

Related rigging question would be how slack should lee shrouds be? Sometimes I'm worried that the shrouds are not tight enough. Any good suggestions for a somewhat novice rigger? Thanks.

Jamie Harrell
74 Typhoon "Osprey"
David Hest
Posts: 26
Joined: Oct 3rd, '05, 13:11
Location: '79 Typhoon Daysailer, "Miss Ty," Hull #21

Re: Typhoon Rigging Question

Post by David Hest »

I also am a novice Ty sailer, so can’t speak with the authority of long experience. I think your intuition is correct that the heavier stern may be causing the rear stay to be slack while the boat is on the mooring.

To help tension the stays on my boat, I recently purchased a Loos gauge. The gauge confirmed what I had suspected - that the rigging did not have enough tension on any of the wires. After tensioning according to the specs that came with the gauge, I noticed that boat heel was reduced compared to normal at the same wind speed. I am guessing this is because the furled headsail/forestay had more tension from a properly tensioned rear stay - thus less sag in the sail/better shape.

If you search this site for rigging tension, you will find lots of good info. Good luck in sorting this out.

David
david wiencke
Posts: 3
Joined: Jul 24th, '06, 21:53
Location: CD25, #160, "Serendipity",White Bear Lake ,MN and Nippigon, Ont. on lake Superior (August)

backstay tension

Post by david wiencke »

I suspect your backstay appears slack at the mooring if your topping lift hangs from the backstay (as it did on my Ty), then if you tension the mainsheet, it creates slack below the topping lift attachment.

The owners manual says you should have about 2" of play on all 4 upper shrouds and 4" of play on the 4 lowers. And NOT to tension stays "BAR" tight, which will drive the mast through the cabin top or pull the chainplates up- I've seen both kinds of damage on Tys.
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tartansailor
Posts: 1528
Joined: Aug 30th, '05, 13:55
Location: CD25, Renaissance, Milton, DE

Loos Gage As A Starting Pointy Only.

Post by tartansailor »

Gents,
You really do not want to "tension" your standing rigging.

You want to "TUNE" your standing rigging.

The only time you use a Loos gage is to set the initial tension to 10% to 12% of break strength.

Then you sail the boat and adjust for sail shape AND repeatability on both port and starboard.

In the end you should wind up around 15% max! of break strength.

This is not my opinion, this is how the big boys do it.

Dick
Viam Inveniam Aut Faciam
david wiencke
Posts: 3
Joined: Jul 24th, '06, 21:53
Location: CD25, #160, "Serendipity",White Bear Lake ,MN and Nippigon, Ont. on lake Superior (August)

Post by david wiencke »

Is that 15% of the breaking strength of the chainplates, cabin top or the stays themselves and how do you calculate that?

This is how I "tune" my boat: (it's probably not how the big boys do it, but it works quite well for me.)

After getting the general tension as described in the cape dory manual, ie: 2" of side-to-side play on all uppers and 4" play on lowers (or you could calculate the breaking strength etc.)

1. I first try to get the mast perpendicular to the boat fore and aft. This can be tricky as you can't just take a square to the cabin top. Make sure the boat is floating on its designed waterline, then sight the mast with something that is perpendicular to the water, like a tower or flag pole or the side of a building. This is done by taking up on one and letting off on the opposing stay.

2. Then get the mast perpendicular side-to-side. You can use a halyard to gauge the distance side to side. Again, taking up and letting off equal amounts from each side so as not to alter the general tension of the rig.

3. Sight up the bead of the mainsail track and adjust the lowers acordingly to get the mast into a straight column. Then sight up the mast from the side to get the mast in column fore and aft, again by balancing the lowers.

Fine tuning: While sailing on a beat or close reach, sight up the mast and observe if the mast bends or bows both side-to-side and fore and aft. Adust the lowers accordingly to maintain the mast in column. For instance I will sight the mast on a port tack, making note of what changes are needed, ie: if the mast is bowing to leeward in the middle I might increase tension on the port lower stay. I don't do this until I'm on the other tack and the tension is off the port stays. Then I sight the mast from starboard tack and adjust accordingly when on the opposite tack.

As far as balancing the trim of the boat fore and aft because you have your engine out on the transom while sailing, I would recommend using weight low (in the bilge), and not way up forward, but rather just forward of the mast base. If you don't need to use your engine on a regular basis, it would be best to store it as low as possible (on a weekender under the cockpit works well). Maybe on a daysailor in the cuddy?

One other thing to consider, especially in a small boat, is that when you put people in the cockpit (as well as engines on the transom), it changes the fore and aft trim. One might consider countering this by placing enough weight low and forward of center to balance the boat. It will sail better!
david wiencke
Posts: 3
Joined: Jul 24th, '06, 21:53
Location: CD25, #160, "Serendipity",White Bear Lake ,MN and Nippigon, Ont. on lake Superior (August)

Post by david wiencke »

Just realized that if you have a fractional rigged weekender, you should only tension the fore and aft stays until they just start to create a bow in the mast when sighting up from the side. You could put more tension (up to 2" play), but that will start to change mainsail shape.
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