Foot blocks with jammers for use in reefing systems

[jeffoaklief]

Hi all,

I am getting ready to rework my reefing system.  The plan is to add the third reef to match my new main and also take the reefing loads off the boom.  Currently the outhaul reef line runs to the front of the boom, down to the deck and then back to the cockpit and this seemed to create some problems during the R2AK.

After looking at a bunch of stuff it looks like things boil down to using either a clutch, a jammer or a foot block with built in jammer.  The clutches are big and bulky (textile clutches are off the list for now even though they are much smaller).  The jammers on the market are either a little too small (Spinlock mini jammer) or stupid expensive.  There do exist foot blocks that have jammers built in that have published load capacities between 2 and 4k lbs.   

Does anyone have experience using this type of foot block?  Think it would work for holding a reef line?  

It is a fat head main, so my guess is that the majority of the force is between the clew and the boom and not the clew and the end of the boom where the reef line turns and runs forward to the mast (Ok.. it has been a while since I worked with force vectors... but it seems to me the more vertical section of the line would take much more load).  

Thoughts?  Cautionary tales?

Jeff Oaklief

Ruf Duck

F9R

[William Quigley]

Where do you plan to attach the foot block (w/jammer)?

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[Paul English]

On Tue, Nov 7, 2023, at 13:14, jeffoaklief wrote:

Hi all,

I am getting ready to rework my reefing system.  The plan is to add the third reef to match my new main and also take the reefing loads off the boom.  Currently the outhaul reef line runs to the front of the boom, down to the deck and then back to the cockpit and this seemed to create some problems during the R2AK.

After looking at a bunch of stuff it looks like things boil down to using either a clutch, a jammer or a foot block with built in jammer.  The clutches are big and bulky (textile clutches are off the list for now even though they are much smaller).  The jammers on the market are either a little too small (Spinlock mini jammer) or stupid expensive.  There do exist foot blocks that have jammers built in that have published load capacities between 2 and 4k lbs.   

I have a (single) textile clutch for my reef currently - the Ronstan constricter style, mounted on the boom. I haven't used it much, but I don't particularly love it - they were used for spin tack line clutches on the Aerodyne 43 (Freja) I did Van Isle and Swiftsure on, and it just seemed *far* too easy to trip them by mistake - and they work "backwards" for all crew. FWIW, the 2 marine engineers on Freja said that typically these clutches are mounted "inside" of some structure, with just the trip line normally accessible.

I really like the look of the Spinlock ones - they provide that enclosing structure, as well as a more intuitive looking button interface thingie. https://www.spinlockusa.com/en-GB/usa/products/xtx

But IMHO both are pretty pricey for what they are!

I have very limited experience with jammer foot blocks, and I'm still looking for a good resource on realistic load calculations.

Does anyone have experience using this type of foot block?  Think it would work for holding a reef line?  

It is a fat head main, so my guess is that the majority of the force is between the clew and the boom and not the clew and the end of the boom where the reef line turns and runs forward to the mast (Ok.. it has been a while since I worked with force vectors... but it seems to me the more vertical section of the line would take much more load).  

Thoughts?  Cautionary tales?

The previous owner set up the reef so that one uses the reef line to pull down the clew as one normally does, but *not* to actually secure it! Despite having the Ronstan clutch in-line. Instead, the low friction ring also had a dyneema strop that one would wrap around the boom and attach to a dog bone. Then you can release the reef line entirely, and you've got a fixed thing dealing with the load while actually sailing. I'd never seen anyone else do this, but it is simple and elegant. Though to shake out the reef you need to ease some tension on the dog bone loop - either by *re*tensioning the reef line, or in my case, easing the outhaul (moves the entire cabin-top mounted boom forward) a bit. Re-tensioning the reef line would definitely be an additional, slowish step while racing, versus just releasing a clutch can cranking up the halyard, but for most purposes, probably fine.

[Ginnie Jo Blue]

Hey Jeff,

This doesn’t answer your question. Instead, it adds a new one…

My reefing lines (currently set to reef points one and three on my main) run down the inside of the boom (clutches are in the boom), to the deck, and back to the cabin to finish in a spinlock. This sounds just like you described and had issues with in R2AK….? If so, mind sharing what the issues were? I remember your crew and you grumbling about the reefing more than anything, so what was the issue? 

Thanks,

Ginnie Jo

On Tue, Nov 7, 2023 at 1:14 PM jeffoaklief <jeffo...@gmail.com> wrote:

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[Jeff Oaklief]

The plan is to mount the foot blocks vertically at the gooseneck open end of the boom with the little cam levers pointing forward and down.  The block would redirect the reef line to the deck turning block (then on back to the winch).  The jammer lever would then be accessible to either engage the reef line or run free.  While tensioning the load would still be going through the gooseneck but once the jammer is in place the tension would be isolated in the boom.

The issue we had on R2AK is that with the reef line spanning from the boom to the deck, every time the mast rotated it would load and unload the gooseneck as it swept from port to starboard.  Particularly bad if we reefed on the uphill side of the boom and then tacked over... it just tightens the beegeebers out of the reef line with the way we have it configured now. There just seemed to be way more load through the gooseneck fitting than seemed prudent.  As for crew complaining about reefing... Hum complains because he is an engineer and thinks that all systems should be beautiful and smooth... perfect.  As for the rest of the crew, they just got tired of reefing all the time... which as it turned out was somewhere around 6-12 times a day.  The same grumbling happens about sail changes... which are also frequent.  :)

I thought about textile... and Vince is on the bleeding edge of that one.  It is an elegant solution... all interior with the trip lines run back to the cockpit end of the boom for easy access.  I figured I would see how his works out over the next few years while I try something a little more exposed albeit probably heavier.  Also, I have a textile clutch on board.  Maybe it is the exposed location but we have found ourselves having to "milk" the cover to get it to hold sometimes... particularly when it is wet.  This may be due to the line we are using... or maybe a loose bungee (although we do check that).

The cool looking jammers are just too expensive.  I do like the Dog Bone idea... I may look at that a bit as it seems even simpler.  Sounds like you need to physically be on the swinging violent end of the boom for that though... which is why I am putting in a third reef line instead of just a tag loop to move the reef line up to the empty third reef clew point.

Jeff

[Ginnie Jo Blue]

Thanks for the explanation, Jeff. It seems like I won't run into the issue you explained since my clutches are within the boom, near the mast, so there is not much tension running vertically when the mast pivots...that is, if I lock the clutches... the weather looks like I may want to do that this weekend! Too early to say, of course. 

I only have two reefing lines and hate the bruisefest battle you speak of when trying to battle for that third reef. Shaun suggested I move one of my lines to the third point, one line to the first point and leave the middle empty. When I want the second reef point, I pull on the third line, move the first line to the second clew point and then tighten the main halyard. It works for cruising but that's not what you're going for. I have three female monohull racers joining me on Undaunted this weekend. If we're reefing all day, I'm sure they'll roll their eyes at the inefficiencies (it's okay, I've already told them all I'm really just in this race to meet my multihull friends in Roche for a party and we should call ourselves "last to finish"). 

G

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[Jeff Oaklief]

Ginnie,

Sounds like your setup is similar to our current one.  Reef 1 and Reef 2 are set up.  There is a loop of thin dynema going between the second and third clew reef points.  To get to the third reef, the first reef line is attached to the tag loop and then the loop is spun to run the free end of the reef line up and back down from the third reef.  Then it gets tied up and reefing resumes as normal.  It works... and most of the time would be fine.  It felt a little sketch when we needed it and had not seen anyone else for a day.

Looks like things are getting light for Saturday... so maybe not that much reefing.

:)

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[Ginnie Jo Blue]

Yay! I've chosen not to look at the report until tomorrow, so thanks for the sneak peek ;). 

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[Shaun Heublein]

I'm interested in what you deside to do. The leader line to the third reef is interesting but I can see how when it's time for reef three you don't want to have to access the end of the boom. (it'll be hairy out there) we will be finishing out our third reef this winter and I was wondering how best to go about adding the hardwear. My current thought is to install a cheek block at the clew end of the boom and then side mount an appropriate clutch at the front of the boom with another cheek block forward of that and turning block on deck to direct back to cabin top winch. I would love to add all this internal but suspect it would likely require major modifications to the boom, or a new one all together (Vince....?😁) I might relegate the external hardware to reef 1 since it may end up more fidly than the stock internal systems already installed. 

[William Quigley]

I've always been wary of reefing lines that lead through what seems like a half dozen blocks to a winch. If you get rid of all the blocks, you don't need the winch.

My old boom had sheaves at the outer end, and cam cleats on the sides of the boom. You could just sit on deck under the boom and pull on them. It wasn't ideal but it worked.

Now I'm using Vince's old boom that has sheaves at both ends and a double jammer/clutch at the gooseneck. I've only reefed a few times with it but it's more effective than my old boom because you can sit facing forward with your feet against the mast base and you get more leverage.

Getting those lines to the cabin top winches would mean at least one more turning block and a deck organizer, and that's only if they happen to line up perfectly. And I would still have to go back to the gooseneck to engage/release the jammers, and to deal with the tack reef.

I still believe that the best time to reef is when you first think about reefing, so being on the cabin top shouldn't be uncomfortable. If reefing is hard, you waited too long.

I'm also curious how others deal with reef tacks. My sail doesn't have cars at the reef tack grommets, and I'm not sure if I want them there because the reefed sail would be pulling the track off the mast since the load is on the track and not the gooseneck. Mark Dix made strops that we ran around the mast and down to a sort of cunningham, but they don't fit the new mast. But without anything keeping the luff tight up against the mast/track, you get a baggy sail.

Bill

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[Vincent DePillis]

On the tack reef:  I have separate tack reef lines for each reef (only have two reefs).  Line dead ends on cleat on mast, goes up through the reef tack (which is a rutgerson ring w webbing reinforcement), down through a mast mounted clutch to a turning block attached to the mast base, and back to the cockpit.  The reef line dead end, and the routing back down to the clutch on the other side, are located so as to pull the reef tack forward as well as down.  No strop needed.

I can now grind the sail down even when there might otherwise be an issue -e.g. down wind.   No more standing at mast and desperately hauling on the luff of the sail.    This set up has greatly increased my peace of mind.

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[Eric Lindahl]

Mine same as Vince more or less.

Eric 

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