On a ‘96 Hunter 42 Passage currently on passage to Guatemala and noticed a popping or thumping sound on deck. Traced it back to the SS Rods. As the boat heels to port or starboard a thump is heard. You can feel it below by placing you hand on each rod. Anyone have any experience or knowledge. Motoring until I can figure out what it might be.
SS Rod popping sound
- Thread starter mesmith1122
- Start date
It much if any. Just had new furling unit and headstay installed by Mack Sails. I traced the occasional thump to the 3/8” outer shroud that extends from the chainplates to the top spreader. I tested both with a Loos PT-3 tension gauge and got 30-32 lbs little rolly out here. Last inspection everything looked great except the headstay was compromised by a failed furler.
Odd that it sounds like it's equally on both sides... one wouldn't think that two fittings would start to degrade together like that. My first thought was an un/poorly seated ball end of the rod (top or bottom).. could be that would would transmit throughout the rig no matter where it's occurring, though. Not a nice situation to be in at sea!
If this rod rigging has balls on the ends then it might be that the rods are loose in their slots in the mast. As they come tight, they would make the noise you describe. Tighten up your shrouds.
This would be my first guess, somethings not tight. The shock loading when the rigging pops I would think is something to be concerned about.
jssailem
SBO Weather and Forecasting Forum Jim & John
- Oct 22, 2014
- 23,147
You might quick check the length of the rods. Using the main halyard as a tape measure from mast head to deck, take the halyard to the chain plate on port and starboard. Does it look to be the same length or is one slightly longer/shorter. Might also grab the offending rod and with feet on gunnel grab and lean out over the water.
What you indicated was an unevenness in the rig when under pressure. Could be the ball ends are ok but the slot they fit in may be elongated on one side. When under pressure the slide that little bit extra.
That is what it sounds like to me. Thousands of mile away. Best of luck.
What you indicated was an unevenness in the rig when under pressure. Could be the ball ends are ok but the slot they fit in may be elongated on one side. When under pressure the slide that little bit extra.
That is what it sounds like to me. Thousands of mile away. Best of luck.
I am not sure the OP is talking about rod rigging per se. I think he is speaking of the stainless steel rods that go from the deck fittings that attach to the shrouds to a beam attached to the hull. This rod is visible inside the cabin on both the Port and Starboard side. There are discussions on degredation (rusting) of the beams where the stainless steel rod attaches. Is it possible that there is some issue with the attachement of the rods to this steel beam resulting int he popping noise. The OP is motoring until the issue is sorted which I think is an excellent idea.
That is correct. It is the stainless steel rod that secures the chainplate. I have been in touch with the rigger who recently replaced my headstay and added a new furler and 135 Genoa. He gave his blessing to tension the lower section of the 3/8” Upper Shroud. Just before beginning this process I recalled Rgranger’s comment regarding mast pumping. And realized we had not experience the thumping sound with the 135 headsail deployed earlier. It only occurred when the staysail on the inner forestay was deployed and occasionally when the sea became rolly! So, rather than tensioning, we deployed the headsail. No thumping all day with moderate wind in high teens. I will use the headsail and avoid the staysail till I have a chance to have the riggers in Rio Dulce check out tensioning headstay and backstay!!
Thanks to all for the quick responses. Great sailing forum!!!
Marty & Annie
SV Anchor Management
Thanks to all for the quick responses. Great sailing forum!!!
Marty & Annie
SV Anchor Management
Hi Marty & Annie. No staysail on our boat and no popping sounds either. At rest standing rigs on both sides remain taut, but under pressure, say at close hauled or reaching in upper teens low twenties apparent, the lee side rigging will become loose. I would consider that normal under those conditions. One thought, have you inspected the chainplate where the SS rod connects to the hull?
Hey Terry!!! We have inspected chainplates and the SS Rods the plates are secured to. Both are great. No deck cracking around the plates! We came thru some storms and 20+ kts wind last night. Lot of bouncing. Genoa and main out, no engine. No thumping. Having the headstay, furler and Genoa recently replaced with the backstay loosened in the process leads me to believe I need some tensioning. Can’t test tension on the water. Will do in Guatemala.
jssailem
SBO Weather and Forecasting Forum Jim & John
- Oct 22, 2014
- 23,147
That info sounds very good.
I know on my boat (mast head rig) that I need to tighten the backstay when I get in a blow. This tightens the forestay and my furler does not thump in wind and wave. Like Terry, when hard on the wind the lee stays release their tension. (Like a bass string not a high E on a guitar.) When at rest both shrouds/stays are taut.
I know on my boat (mast head rig) that I need to tighten the backstay when I get in a blow. This tightens the forestay and my furler does not thump in wind and wave. Like Terry, when hard on the wind the lee stays release their tension. (Like a bass string not a high E on a guitar.) When at rest both shrouds/stays are taut.
Hi Marty & Annie. Thanks for the additional information. Some time ago Hunter sent me a diagram of the P42 chainplate. I've never inspected ours. Do you happen to have picture of yours that you can post? Their diagram shows a long plate bedded in the hull FRP with what appeared to be cables spread across the plate that come together and attach to the SS rod thus distributing the load across the plate.
I had heard the same regarding SS Rod bedding but have not seen ours. I did inspect the cylinder nuts that appear to lock the rods in place when we purchased the boat 2 1/2 years ago in Guatemala. They looked in great condition with no rust or corrosion.
Actually, they should always be tight, be tensioned, so you don't have a shock load if the wind changes suddenly. This can break shrouds, even take down a rig.
Update on SSRod popping. Once we got a little calm in Cozumel anchorage, I was able to use a Loos PT-3 tensioning gauge. Upper & Intermediate shrouds barely registered on the gauge. Very loose. Lower shrouds and diamonds were at 10-11%. Brought upper and Intermetiates up to 10-11%, checked mast side to side with main halyard midship. Popping is gone, sail handling & performance was a major difference especially when we hit storms at lighthouse Reef on into Livingston. On the dock at Catamaran Marina. Plan on scheduling a rigging survey once we are rested up. Thanks for all the excellent advice!!!