Chafing caused by Bungee Snubbers

Newsgroups Archive Prior to 2025
1

Vela33
Brian Godfrey - Vela - NS33 #77 - San Diego
3h

Create General topic
Chafing caused by Bungee Snubbers
I have been using those Bungee Snubbers (I think that’s what they are called) to mitigate the shock on my sheet when tacking or jibing. They are easy to install and I’ve found that four of them strung along the first few feet of the sheet work wonders. But the last time I was on the boat I noticed that they are really chafing the line badly. I was going to replace the sheet soon, anyway, but now it is a much higher priority. And I’m probably going to need to replace the Bungee Snubbers with something else.
So questions:

  1. I know that others have used those rubber mooring shock absorbers. I avoided those the first time around because of the increased hassle of installing them. But that’s minor compared to the hassle of replacing the whole sheet. Has anyone used both these and the Bungee Snubbers? And if so, which did you prefer? If I do use one of these mooring line absorbers, how many wraps should I take for best effect?
  2. Is it possible to use some sort of chafing gear on the first few feet of the sheet and continue to use the Bungee Snubbers? I don’t know about this one, though. It would be quite a hassle replacing the chafing gear when it inevitably wears out.
  3. Is there some other method (other than awesome seamanship - which would be someone else) that I should consider?
    I am posting this directly to the Discourse group. It is my understanding that it will also be distributed to the GG email group. We’ll see how that works out…
    Thanks,
2

I have using one of these for years with no issues
https://www.wholesalemarine.com/sea-dog-mooring-snubber/?gad_source=1&gbraid=0AAAAAD-TdAC_zFeiq6DYjAvtWGnx3g8xC&gclid=EAIaIQobChMI_fS82ay_iwMVjzMIBR3ANiv7EAQYBCABEgIz6_D_BwE

Peter Farley
Knot in a hurry u30 #328
Keyport nj

3

Yeah, that’s the kind I was asking about. How many wraps do you take around it to get the best effect? Do you really feel it working if your tack or jibe goes a little hard?
These are the kind I have: https://sailcare.com/bungy-mooring-compensator/ They were discussed at length in a previous thread. Anyone who uses them might want to check the line for chafing.

4

I have 5 wraps around the snubber between the two end points. I use a 1/2 one. Probably stiffer than what you are using. In 15 knots of wind it flexes in and out about 1 inch while ride the waves. I have had 2 accidental gybes. Stretches about 4 inches. It is heavy so it will hold the line down in light wind.

5

I use a Seadog one, gybe all the time and have no problems with unusual wear.

Joe Valinoti
S/V iL Gatto NS30U #221
Sea Harbour YC
Oriental, NC USA


[details="(attachments)"]

![NS30Snubber 001.JPG|2288x1712](upload://ht57KAggLidtYYSxySHvvRX6AZi.jpeg)
![NS30Snubber002.JPG|1712x2288](upload://su2u05qiwmtvpB52Dt9FDuQIv2b.jpeg)

[/details]
6

I envy owners that sail enough to experience mainsheet chafe. ( HERE ) is a link to a photo of the mainsheet snubbers installed on Soave when I purchased her in '23. I haven’t noticed any chafe and I guess the first step ( if I notice chafe ) would be to move them an inch or so to extend the mainsheet life another few years. There are about 8-10 of these snubbers in total. They are very stiff, but all give a little when highly loaded. Maybe the snubbers that are chafing on other boats are lighter and allowing lots of movement under relatively light loads? I don’t think we want our snubbers to yield till they experience about 800 lbs of load.

I saw in another post from an owner who had updated to a dyneema mainsheet which struck me as an undesirable choice given our shared concern about shock load when jibing. A little give in the mainsheet under shock load is a good thing.

I’m also wondering if chafing ( for folks experiencing it ), is happening while sailing or if it’s happening at the dock ? I’m ashamed to admit that Soave spent way too much time at the dock last season, and our slip ( as shown below ) if very well protected. It may not be that the snubbers on Soave are gentle, maybe it’s the lack of any wave action at dock ? While at the dock I rig a temporary line from the wishbone to an aft corner casting, to bring the boom a little off center. Once rigged the wishbone sets nicely without any side to side bounce.

Soave's Slip.png
Soave's Slip.png2254×942 406 KB

Rob
s/v SOAVE
NS33 #009
Cedar Point YC
Westport, CT

7

I think you need to sail more! :slight_smile:
Those are the same ones that I use. My boom is well restrained except when actually sailing, using the same method you use. Weather is very mild here in San Diego, so probably no chafing at the dock. (We’re currently experiencing our big “storm” of the year: temps in the 50s, 3 days of drizzle and winds sometimes getting into the high teens. It’s why we retired here from the Oregon coast.)
I try to sail once a week and probably manage about half that often. More in the summer and less in the “winter” as I am dependent on getting people to come along. And I generally sail for at least six hours with at least four in the ocean. (I’ve got a nice Hobie Kayak if I just wanted to bob around in the bay for an hour.) That’s probably the difference.

Oh, another potential difference: your sheet appears to be much newer than mine. I wonder if UV degradation has made mine more susceptible to chafe? It really is due for replacement.
Anyone else with these snubbers out there? Two data points does not make a trend.

I was planning on replacing the sheet with Viper, but your point is well taken. I want stretch. Maybe I should replace it with nylon!
Hmmm … I just looked on the Samson Ropes website. The owner’s manual calls for 1/2" polyester, Samson lists the “average strength” of their 1/2" XLS3 polyester/polyester line at 8700 lbs. They list the average strength of their 1/2" Super Strong ™ double braid nylon at 8600 lbs. A 1% difference.
And elongation (stretchiness) of the nylon is twice that of the polyester. If the snubbers don’t do much until they get an 800 pound load, that’s about where the nylon experiences 3% elongation. And since our worst shocks happen with more sheet out, say 75% or 75’ in the case of my boat, that would be around 2’3" of stretch with the nylon. That sounds much more gentle than what these four snubbers can provide.
So why do we use polyester for the sheet instead of nylon? How does it hold up to winches?

8

Hi Brian,
Yea !! I’d gladly replace a chaffed mainsheet after sailing that much !

Regarding the choice of material for the mainsheet. I am NOT a materials guy, the following is just the intuition of a recreational sailor.

I will stick with the material prescribed by the builder/designer until either; I am certain I am smarter than the builder/designer ( NOT likely ) OR some technological development has made the their selection obsolete. Since nylon rope has been available since the 1940’s I doubt it was overlooked when our boats were built. Unfortunately, my logic has kept Dyneema out of the mainstream longer than it should have. There are some applications where strength, low stretch, and low weight are wonderful additions to our Nonsuch boats. Not in the case of our mainsheets.

The physical property we’re looking for ( in a mainsheet) is stout ( low stretch )while it’s in the normal working range and forgiving ( stretches ) when approaching the breaking limit of our deck fittings. The problem with nylon is that it starts yielding at a low load and would annoy our Mainsheet trimmer. It probably still has plenty of stretch left as it approaches it’s limit of our deck fittings.

Since you are handy with numbers, you could guess the speed of the wishbone during a crash jib, guess the weight of the boom, and then calculate the shock load ( energy required to stop it in some distance… probably pretty close to the 1’ that you mentioned ). Not sure how much having 2’ over 1’ helps… I know 1" would be A CRAZY amount of energy to absorb in a very short interval.

Knowing… total load = equals working load + shock load… and that load shock load only occurs while the wishbone is decelerating… The ideal mainsheet would have zero stretch in the working load range and lots of stretch when load exceeds the maximum expected working load.

Unfortunately ideal materials don’t exist… Polyester may be a good compromise.

Snubbers are not mentioned in my manual, but they are pretty common on Nonsuch boats… so I left mine in place.

Also, good to consider the weak link(s) that we are protecting. It might reduce risk more if I do a detailed inspection of the deck hardware, through bolts, and backing plates… since they are likely to be my critical failure point.

Ahhhh ! Another thing to check instead of sailing. Thank goodness for the off-season… Oh wait you don’t have an off-season.

Rob
s/v SOAVE
NS33 #009
Cedar Point YC
Westport, CT

9

No, no off season. But I have off days! :slight_smile:
Well, I also have work days and sailing days. I spend two days and one night a week on the boat. I work on maintenance and upgrades on one of those days if I am sailing that week and both if I am not able to. But the truth is, I am from wet country and it is SO DRY in Escondido where we live now that I spend much of those work days just relaxing and soaking up some humidity. Or negative ions. Or whatever your particular persuasion attributes that really good feeling you get on the water to. So I don’t get as much done as one would expect from so much maintenance time.

10

I have been using the SailCare Bungy Mooring Compensator, noted above by Brian Godfrey, for several years. I have two on my mainsheet above the block at the aft centerline to absorb some of the ‘bang’ if I happen to jibe (rare) or when the seas are choppy and the boom is bouncing around a bit. I believe it helps, but I do not have factual information to support or deny my opinion. They are spaced far enough apart so they do not rub each other. I have not noticed any chafing near them since installing them.

I also use two of these same Bungy compensators on my anchor line to lessen some of the shock on the bow rollers/Sampson-post if conditions are choppy when anchored or a passing boat’s wake is encountered. I do notice a difference in this application. Since adding an electric windlass last season, I need to put the Bungys in place after deploying the anchor/line (they can’t pass through the windlass), but it is easy enough to do quickly once the anchor is set. Prior to that I just left them on the anchor rode and adjusted their position based on the amount of line that was out. Again, have noticed seen any chafing associated with the Bungy.

Peter Grabow
S/V CAKE WALK III
1987 30U 430
Jersey City, NJ (soon to be Stamford, CT!)

11

The chafing is on the line, not bungee-to-bungee. But I’m coming to the conclusion that it is happening because the sheet is just too old and the sheathing is UV damaged. It will be replaced and we’ll see how it goes after that. Yes, these snubbers are very easy to add or remove and I’d just as soon be able to keep using them. And I do notice less shock from long tacks or jibes.

12

We have used these little beauties for a long time and they work very well. Easy to put on and. not so heavy as to interfere with the sheet, We use 2.

https://sailcare.com/bungy-mooring-compensator/

Thor