Checkstay - lower shroud

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Frednatal
Posts: 23
Joined: 06 Aug 2009, 14:29
Sail number: BRA 66
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Checkstay - lower shroud

Post by Frednatal » 28 Apr 2011, 02:49

If I do not have a spreader I can use a shroud from the middle of the mast fixed on deck a little aft the mast as a checkstay?
Fred Schmidt

http://www.frediom.wordpress.com
http://www.iomdesign.worpress.com
http://footybrasil.wordpress.com/

Hiljoball
Posts: 283
Joined: 06 Jan 2006, 00:47
Sail number: CAN 307
Club: West Coast Radio Sailing
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Location: CAN
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Re: Checkstay - lower shroud

Post by Hiljoball » 28 Apr 2011, 04:59

Sorry but no.
in F 3.4
Height of checkstay rigging point above heel point ...................... ..... 100 mm

(and note it is the heel point and not the deck limit mark)

John
John Ball
CRYA #895
IOM CAN 307 V8
In my private capacity

Frednatal
Posts: 23
Joined: 06 Aug 2009, 14:29
Sail number: BRA 66
Design: Xique-Xique
Location: Natal, RN, BRA
Contact:

Re: Checkstay - lower shroud

Post by Frednatal » 28 Apr 2011, 14:07

Hiljoball wrote:Sorry but no.
in F 3.4
Height of checkstay rigging point above heel point ...................... ..... 100 mm

(and note it is the heel point and not the deck limit mark)

John
Hi John, thanks for your replay.

But I do not understand. As we do not have figures to show what the words intend I am in doubt.

By ERS F.1.6 : " CHECKSTAY - Rigging providing aft support for a mast spar at a point, or points,
between the lower limit mark and the forestay rigging point. "

How I can have a checkstay with 100 mm max, supposing that the heel point is at deck?

What the IOM rule want say with: " Height of checkstay rigging point above heel point ..................... ..... 100 mm" because in ERS spar rigging point is - point that rigging is attached

I am in doubt about this.

Cheers
Fred Schmidt

http://www.frediom.wordpress.com
http://www.iomdesign.worpress.com
http://footybrasil.wordpress.com/

Hiljoball
Posts: 283
Joined: 06 Jan 2006, 00:47
Sail number: CAN 307
Club: West Coast Radio Sailing
Design: V8
Location: CAN
Contact:
Canada

Re: Checkstay - lower shroud

Post by Hiljoball » 28 Apr 2011, 15:33

The class rule over-rides the ERS. The height of the attachment on the mast, above the mast heel is no more than 100mm, regardless of the position of the lower limit mark.

The class rules allow only one pair of shrouds.

John
John Ball
CRYA #895
IOM CAN 307 V8
In my private capacity

Frednatal
Posts: 23
Joined: 06 Aug 2009, 14:29
Sail number: BRA 66
Design: Xique-Xique
Location: Natal, RN, BRA
Contact:

Re: Checkstay - lower shroud

Post by Frednatal » 28 Apr 2011, 16:47

Hiljoball wrote:The class rule over-rides the ERS. The height of the attachment on the mast, above the mast heel is no more than 100mm, regardless of the position of the lower limit mark.

The class rules allow only one pair of shrouds.

John
------------------------------------------------------
Hi John

F.3.3 FITTINGS - ( MAST )

(a) MANDATORY

(1) Mainsail halyard(s) fitting(s) or opening(s).
(2) Shroud fitting(s) and/or opening(s).
(3) Gooseneck.
(4) Kicking strap fitting.

(b) OPTIONAL

(1) Wind indicator and/or its fitting.
(2) Backstay crane and its fitting.
(3) Headsail stay fitting and/or opening.
(4) Headsail halyard fitting and/or opening.
(5) Pair of spreaders and their fittings(s) and/or opening(s).
(6) Mast spar rings and/or loops to attach mainsail luff to the spar.
(7) Mainsail jackstay fittings.
(8) Mainsail tack fitting(s).
(9) Mast strut and its fitting.
(10) Checkstay fittings(s).
(11) Deck fitting.
(12) Heel fitting with or without mast jack.

F.5.2 ( STANDING RIGGING )

CONSTRUCTION

(a) MANDATORY

(1) Pair of shrouds.
(2) Backstay.
(3) Headsail boom swivel.

(b) OPTIONAL

(1) Pair of checkstays if a mast strut is not fitted.
(2) A headsail stay less than 1 mm in diameter.
(3) A mast spar jackstay less than 1 mm in diameter.

What which would " checkstays " " strut " ?

Strut for me work in compression, like spreaders. I do not have.

Checkstay by definition is similar to shroud?

I would like visualize what the rules intend for: " (1) Pair of checkstays if a mast strut is not fitted. "

Cheers
Fred Schmidt

http://www.frediom.wordpress.com
http://www.iomdesign.worpress.com
http://footybrasil.wordpress.com/

Hiljoball
Posts: 283
Joined: 06 Jan 2006, 00:47
Sail number: CAN 307
Club: West Coast Radio Sailing
Design: V8
Location: CAN
Contact:
Canada

Re: Checkstay - lower shroud

Post by Hiljoball » 28 Apr 2011, 17:49

A mast strut has fallen out of fashion since the raised foredeck and the advent of the mast ram. On a flat deck and deck stepped mast, a mast strut was used to brace the lower section of the mast to resist the forces of the goose neck (same function as a ram). The check stays are an alternative to the strut. By setting them up either side and slightly aft of the mast, they provide an opposing force to the goose neck and yet do not get in the way of the job boom, the way a strut could.

As written in the IOM class rules, the check stays are limited as to how high they can go. They only make sense on a flat deck, and deck stepped mast as the measurement is taken from the mast heel.

So the answer is still no. . you cannot set up a set of lower shrouds to mid mast and call them check stays.

John
John Ball
CRYA #895
IOM CAN 307 V8
In my private capacity

Frednatal
Posts: 23
Joined: 06 Aug 2009, 14:29
Sail number: BRA 66
Design: Xique-Xique
Location: Natal, RN, BRA
Contact:

Re: Checkstay - lower shroud

Post by Frednatal » 28 Apr 2011, 19:33

Hiljoball wrote:A mast strut has fallen out of fashion since the raised foredeck and the advent of the mast ram. On a flat deck and deck stepped mast, a mast strut was used to brace the lower section of the mast to resist the forces of the goose neck (same function as a ram). The check stays are an alternative to the strut. By setting them up either side and slightly aft of the mast, they provide an opposing force to the goose neck and yet do not get in the way of the job boom, the way a strut could.

As written in the IOM class rules, the check stays are limited as to how high they can go. They only make sense on a flat deck, and deck stepped mast as the measurement is taken from the mast heel.

So the answer is still no. . you cannot set up a set of lower shrouds to mid mast and call them check stays.

John
Thanks John by the answers. When we read checkstay, we think in reals checkstays. When I read checkstay I realize the true action of a checkstay, similar to a shroud. I think more one time that a figure is better than thousands letters.

Cheers
Fred Schmidt

http://www.frediom.wordpress.com
http://www.iomdesign.worpress.com
http://footybrasil.wordpress.com/

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