Stainless wire rigging condition

[sailnaway]

What should we be looking for as far as wire fatigue and how can we see it. I have kept a close eye on my rig and I see no cracks no broken wire no rust so how do we know when its time for new gear.I do keep my wire clean with polish as far as I can reach and I spray everything with WD40 on a regular basis but I have no way of knowing what the last owner did or how old the rig is.

[GordMay]

See the “ Rig Inspection Guide” at:
http://cruisersforum.com/showthread.php?s=&threadid=1290&highlight= rigging

Cracks in rigging components, especially cracks that are orientated transverse to the load are a sign of impending failure. Cracks can be found using visual inspection (using a 50 x magnifier), or by dye penitrant testing. X-ray testing, eddy current testing, ultrasonic testing and other professional methods can also be used.

For visual inspection, the wire or rod and fittings must be cleaned or polished to expose the cracks. For preventive maintenance, polish the surface of your stainless with a stainless steel polish. Polishing creates a smooth metal surface and helps minimize the number of pits, valleys and microscopic cracks where moisture can reside and create the environment corrosion loves.

Rusty areas frequently indicate cracks underneath. In addition to cracks, you should look for corrosion, pitting, and rust.
Alignment of the wire and fittings to the load is very important for the reliability of rigging. Misalignment of fittings, frequently caused by interference or bends should be checked.
Kinks or bends in the wire also result in increased local stress and the likelihood of a short life. If a fitting or wire has operated in a bent, kinked, or misaligned condition, it should be replaced as the damage due to cycling cannot be undone.

Quick Checklist:

Inspect wire rigging. Note the tops of rigging eyes, looking for wire barbs or signs that the wire is starting to fail. Prepare to replace where necessary.

Lubricate turnbuckles.

Inspect mast and fittings. Note corrosion of any fittings or metal parts. These should be replaced.

Inspect mast boot or tabernacle fittings. Look especially for corrosion or leaks. Replace or refit where necessary.

Replace bent and worn cotter pins. Replace all snagging fittings.

Check mast wiring for continuity and masthead lights for function. Replace burned out lights.

Touch up paint and varnish.

Clean and wax metal spars.

Inspect all running rigging for chafe and wear. Reverse halyards. Replace worn lines.

Inspect and lubricate all winches. Ensure you have a full set of winch spare parts in the toolbox.

[RichH]

Checking for ''brittle failure/fatigue''.

In addition to GodMays post, I''d like to add that it may be of benefit to remove the rigging, one piece at a time, and off-the-boat, perform a dye penetrant inspection (Magnaflux, etc.) do discover fatigue and micro cracks that are invisible to the naked eye. WEST and other suppliers carry the dye penetrant - a three part system of dye, developer and cleaner. Dont do this ON the boat as the dye will penetrate the gelcoat and NEVER come out.
Be suspicios of any fitting that has developed ''dull'' spots on the surface. Stainless is NOT a good material for fatigue/cyclic loaded items, unless the parts are grossly overdesigned or are rarely loaded, the ''servicelife'' is very short. The only way to analyse is a dye penetrant inspection of other ''magnetic'' inspection. If the rigging is ''old'' - simply change it is the best policy.

Ductile Failure. If you have the *precise" length dimension of the original assembled stays, etc. check this value versus the current length. Ductile failure will result in permanent elongation (due to ''yield''). Easy to analyse if you have the precise original dimensions.

;-)

[capttb]

Rich, I assume Magnaflux is rather expensive, I''ve ordered it to be done on equipment but never saw the bills, just the pained look on the finance people. Is there some general guide or price point where it''s cheaper to replace than test ?

[GordMay]

“Magnaflux” (Dry - Non-Fluorescent) and “Magnaglo” (UV - Fluorescent) materials are used with Magnetic Particle Inspection systems to locate surface and subsurface flaws in ferrous parts.

Magnaflux® “Spotcheck” Dye Penetrant Inspection 16oz can:
http://store.weldingdepot.com/cgi/weldingdepot/SKx.htm
Cleaner $5.71 + Developer $6.71 + Red Dye $7.43 = $19.85

Instructions for Spotcheck® Red Dye Liquid Penetrants
1. Preclean inspection area. Spray on cleaner. Wipe off with cloth.
2. Apply Penetrant. Allow short penetration period.
3. Spray cleaner on wiping cloth and wipe surface clean.
4. Spray on a thin, uniform film of developer.
5. Inspect. Defects will show as bright red lines in white developer background.

[paulk]

And just to make it even more fun, be advised that even though our standing rigging was dye-tested (and passed) before a transatlantic trip, we got to the Bay of Biscay off Arcachon and had a lower shroud part at the hounds. The eight weeks or so of constant sailing, across the Atlantic, then up the Irish Coast to Scotland, the Heberdies, and then down to Spain apparently fatigued the metal until it broke. One does come to a time when it
becomes advisable to replace the standing rigging. The number I''ve been hearing is about every 20 years. Yours may last 50, or the new rigging you put in may break on the first outing. If we knew all the answers, we wouldn''t need to go to church.

[sailnaway]

Well I guess in all my years of sailing I have never lost a piece of rigging so it makes me a little nervous. I have an old guitar I beat on allot less than I use to but the strings are three years old and if that is any indication of how metal can be streched and left under a constant load well maybe this is a good test. I don''t have a tuning pipe large enough for this wire anyone have a Tuba.