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 on: May 13, 2019, 06:02:21 PM 
Started by rlc - Last post by wnethercote
And my submission to peter's forum on runners:

"Hello Peter,

I am following up on my Runner Tracks article.

First I am solidly behind your goal of making our technical specifications clearer to users, and of making enforcement of technical specifications practical without resort to cutting up runners or sending them away for non-destructive testing (such as radiography or ultrasonic survey).

I am uncertain about making the construction of insert runner bodies totally free. As a home builder I would take advantage of it by using a thinner wood core and increasing my carbon fiber stiffening thickness. I do not think that I would ever build a foam-cored runner body. But I am concerned that allowing such a change would have a negative effect on the market value of current runners. The rules change would not affect their legality, as you say, but it might affect their resale value if newer runners were ween to be 'better' in some way.

Warren Nethercote, KC-3786"

Peter has provided responses to both my submissions.

 on: May 13, 2019, 05:58:31 PM 
Started by rlc - Last post by wnethercote
Bob, here is what I recently posted to Peter's forum on masts.  I also did a runner post, to follow.

"I am following up on my Runner Tracks post, with a little additional detail.

I am not convinced that deleting current mast weight and centre of gravity restrictions would be performance neutral.  If I assume a 2.2Kg ballast weight at hound height in a 4.6 Kg mast I can derive a centre of gravity height for that 4.6 Kg mast by assuming that the ballasted mast had the minimum legal CG height.  The result is a CG height of 1604 mm for the 4.6 Kg unballasted mast.  Figure 1 shows this CG and the minimum legal CG.  Both gravity vectors point near the leeward end of the runner plank, about 200 and 400mm from its end, respectively.

The mast weights create a restoring moment that opposes the sail's capsizing force.  The unballasted mast is only 65% of the weight of the ballasted mast, but its gravity vector is twice as far from the leeward runner, so the lighter, lower-CG mast has 130% of the righting moment of the heavier mast.  In lighter winds, the mast will bend less and the righting arms of the two masts will be similar, so in lighter winds the heavier mast should have higher righting moments.  But in lighter winds, the lighter mast will be more desirable for weight reasons alone.

I don't think the differences are big; indeed, in Figure 1 the lighter mast only has about 4 or 5 N-m better righting moment.  What is of greater concern is shown in Figure 2.  The righting moments don't really act around the leeward runner, but around the line between the leeward runner and the bow runner.  The mast centre of gravity might actually be to leeward of that line in Figure 1, in which case there is even a bigger advantage for the lighter mast.

The mast centre of gravity rule is a pain in the neck without doubt.  Are the advantages of a lighter mast that I claim worth worrying about?  Perhaps not, but if the perception is that the advantages are significant then dropping these requirements may have negative effects on current mast values."

Peter has responded there. My estimates of ballast at the hound is on the high side.

 on: May 13, 2019, 12:21:23 PM 
Started by rlc - Last post by rlc
Please use this forum for discussion concerning the specification changes suggested by Peter Hamrak that appear in the May issue of Runner Tracks.  This is a neutral forum that is not sponsored by the author of the proposals as opposed to the one suggested in the runner Tracks article.  Furthermore please be aware that the proposals as they appear Runner Tracks will not likely be the final version of the proposals.  The proposals must first be reviewed by the Technical Committee, and they may edit those proposals in any manner they choose.  They can also make recommendations with regard to those proposals before they are voted on, but we will be voting on them.  Peter Hamrak is on the Technical Committee.  A robust discussion concerning the runner and mast change proposals will be of benefit to everyone.  Further commentary on the other two proposals that were rejected is also welcome. US3433

 on: May 04, 2019, 06:59:27 PM 
Started by wnethercote - Last post by wnethercote
This was a topic intended for the 2019 Annual Meeting, but poor attendance prevented its discussion.  We have an opportunity to add it to the next on-line ballot, but before doing so, member input would be valued.

During the run-up to the 2019 Gold Cup the Governing Committee became aware of the possibility of an entrant to the event who was generally regarded as a reckless sailor, if not unsafe.  It was of concern to the Governing Committee because of a member’s right to sail in the Gold Cup and Continental Regattas, whether under IDNIYRA or IDNIYRA EU governing documents, or the NIA rules.  In the end, the sailor did not enter the Gold Cup and NAs, but the concern remains.

The ‘soft-water’ rules allow for exclusion of entries and It is suggested that the IDNIYRA by-laws be amended to allow for rejection of entries.  Ultimately, such provisions might be transferred to the EPIC agreement, were it accepted by IDNIYRA.

The soft water rules consider exclusion of competitors for soft-water sailors:

The organizing authority or the race committee may reject or cancel the entry of a boat or exclude a competitor, subject to rule 76.3, provided it does so before the start of the first race and states the reason for doing so. On request the boat shall promptly be given the reason in writing. The boat may request redress if she considers that the rejection or exclusion is improper."

US Sailing prescriptions to this rule add that “an organizing authority or race committee shall not reject or cancel the entry of a boat or exclude a competitor eligible under the notice of race or sailing instructions for an arbitrary or capricious reason or for reason of race, colour, religion, national origin, gender, sexual orientation, or age.”

It is proposed that the following provision be added to the IDNIYRA by-laws, either under the race system or racing rules sections.
"Notwithstanding members’ rights to sail in IDNIYRA regattas (IDNIYRA Constitution Article V.A or Organization of the INDIYRU EU Article 2.c) The organizers may reject or cancel the entry of a sailor or exclude a sailor from competition provided the organizers do so before the start of the first race of a series and state the reasons for doing so.  Such reasons will normally constitute a breach of the common sense, safety or good sportsmanship components of NIA, Part IV, A, Fair Sailing. Approval of a majority of available Governing Committee members is required for such action.  On request the sailor shall be given the reason in writing.  The sailor may protest the action in accordance with NIA, Part V, Protest, Disqualifications, Appeals, but only on the basis that the action was unjustified or improper. The protest shall be heard at the close of registration.

An entry for a sailor eligible under the notice of race or sailing instructions shall not be rejected or cancelled for an arbitrary or capricious reason or for reason of race, colour, religion, national origin, gender, sexual orientation, or age."

Again, if you have views on this, please post a response.

Warren Nethercote, Commodore IDNIYRA

 on: April 30, 2019, 07:50:59 AM 
Started by dnus4925 - Last post by Bob Gray
5 lbs, is typical

 on: April 29, 2019, 12:05:10 PM 
Started by dnus4925 - Last post by dnus4925
What sort of batten deflection numbers are there? My top batten in my FO1 is 13.8lbs. That seems a little stiff.

 on: April 04, 2019, 08:19:29 AM 
Started by petej33 - Last post by petej33
These are no where near the quality of J's, Gretchen's, Cathy's, Debbie's or some of the others that were out taking photos, but here are some pics from last season. Happy to share the original just email me with the picture number and I can send you the file. Not sure these are working as links, you may have to cut and paste them, sorry.




 on: March 31, 2019, 03:20:02 PM 
Started by tasar - Last post by tasar
Clean solid stock boat with hardware upgrades, $3000. Custom trailer $375. acat40@gmail.com

 on: March 24, 2019, 06:37:42 PM 
Started by JR FRANCIS - Last post by JR FRANCIS
Needed 1/4 insert steel
Stainless or sarns steel.
Let me know what you have

 on: March 22, 2019, 08:14:04 AM 
Started by Maxim R161 - Last post by dn4379
  If the mast is bending enough, raking it back may make it too soft and maybe risk breaking it.  If you can move the plank forward, maybe 3 inches or so form max forward, your body will have more righting moment to resist the hiking. Also move back in the cockpit to increase righting moment.  I would advise loosening the side stays a bit to reduce the healing forces of the rig. If the plank is stiff and the side stays tight the rear runners will break loose easier and risk spinning out.  Softening the plank in the offseason will help a lot. Get some deflection numbers from a good source.  Figuring these things out is half the fun and never ending.

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