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Ted Duke started this compilation and I dug through the archives and found other stuff.  I hope it is helpful.  Additions are welcome and I will try to keep this current.
Rye Gewalt

General Information:
I have a couple questions I'd like to ask concerning these slugs...

1)  The web page on rig mods has info on installing slugs using shackles.  The slug part # from Sailrite is #23312.5.  What is the number for the shackle?

The part number for the 5/8" shackle is 24105.5 for a 5-pack.

2) Has the nylon in the slug and shackle stood up well to sunshine?

Yes .. actually, there isn't that much exposure over the course of a year.

3) What is the viewpoint on the correct number of slugs to use on a P15?

They come in 5-packs, so order two packs.

4) What is the best placement of slugs around the location of the long batten?

One a few inches above; one a few inches below. For overall group spacing, count this as "one", in a group of 9 to space out along the luff rope.

5) IM will have slugs installed on your mainsail if you send them the sail (actually, to their sailmaker, I believe).  Has anyone out there done this, and, if so, how has it worked out and where do They install the slugs around the long batten!!

If you can poke a small hole with an awl, and tighten a small shackle screw with a screwdriver, you can do it yourself. Why send something so simple off for someone else to do??

      How far from the batten "shoe" is the closest sail slug. I had nudged one in the small triangle made by the "Pocket end Protector" and the Luff bolt-rope. That held the batten in place pretty well. I now have a full batten car (Dutchman's), Sailrite catalog #567, but that had to be jury rigged by the manufacturer as they are not designed for oval masts. (I had to make a couple trips to get it done right but fortunately they are located a few miles from where I live). If I had to do it again I probably would just put another slug on top and as close to the Protector as possible instead of getting a batten car.
Lionel L. Galibert
P15 #2072 "KIROLOU"
Hudson River/Long Island Sound
ICQ 10084021

I installed sail slugs on my P15 this past winter and have now sailed it three times with them and am very happy with them.  If you trailer sail,  however, I'm not sure of there real usefulness. They make raising and lowering the sail much easier, but only if you can leave them in the groove all the time,
with a sail-stop at the bottom of the groove to keep them from falling out as you lower the sail.

I was told the long batten would cause a problem with sail shape when using slugs.  So I asked Sailrite where to place  slugs around the long-batten pocket.They said :"one just above the pocket, one just below it".  I did that and the shape while sailing seems fine.  You do have to have good tension in the sail luff rope, however.  To help achieve that, after raising and cleating the halyard tight, I push down on the forward end of the boom and reclete the boom/tack down haul line (or whatever it's called!) to add more tension to the luff rope.

The spacing of the two slugs around the long batton is such that when I lower the sail, the batten can twist 90 degrees so that it lays on the boom better when "folding" up the sail and lashing it to the boom.  I replace the original batton with a more flexible one (the kind they cut-off to what ever
length you specify) and attached it to its pocket with a 1/4" bolt.  At the upper end of the batten, I filed a notch.  I then tied a loop of line from one sail gromment to the other and this loop is then "snapped" into the notch, creating a slight compression in the batton for sailing.  When I lower the sail I
can snap the line out of the notch, which releases the compression in the batton and makes folding up the sail onto the boom easier and neater (but not necessarily neat:) ).

Because installing slugs does move the sail aft a bit, I move the clew outhaul eyestrap back as far as possible on the boom.  I also made a change at the top of the mast because of the sail being back farther.  I noticed as the sail was being raised, the head of the sail was being pulled into the slot in the
mast, causing unwanted friction as the sail neared the top (the "pulley" at the top of the mast is position to pull the sail straight up only if the sail is in the groove).  To correct this, I added an Upright Lead block (pulley) to the mast to space the halyard out, more inline with the sail's new position.
Explaining this in words is hard, but I have taken a picture of it and will scan it, so if anyone out there wants to see it, e-mail me and I'll send you a e-mail with picture.  I'll also send one to the web site so maybe it can be seen there.

2) Installing sail slugs on the P-15 is a bit more problematic and, while the benefits of reduced friction and easier feeding into the track are available, the sail will still not store neatly on the boom without fussing with the top batten.

Elaborating on point #2, it is the top, full length, batten which poses the difficulties for the sail slug conversion. The compression forces on that batten WILL find their way to the mast one way or another. A proper job of installing slugs will include changing the batten pocket reinforcment to one extended for use with slugs. Sailrite sells these (they now have their catalog online, if you'd like to take a look at these parts). If this is not done the result is the problem I described yesterday, where the batten crunches the (now exposed) luff tape and bolt rope, creasing the sail in the process.

The top batten also poses some disadvantages when lowering the sail. Because the batten is not perpendicular to the mast, it does not want to lay flat on the boom when the sail is lowered and the luff is still held in the track by the slugs. To store the sail neatly on the boom the batten can be removed OR the luff can be freed from the track above the batten allowing the batten to be rotated parallel to the boom. This can be accomplished by attaching the slug above the batten with a shackle.

One method I've used to solve the problem of keeping the top batten fitted tightly  and keeping sail shape:  insert the batten into the pocket as far as it will go;  drill a hole through both the batten pocket and the batten; insert a small stainless  steel bolt, fasten with nut.  Replace batten ties with small shock cord.  The shock  cord adjusts the tension and shape of the sail.  The batten will still 'bow' when the  sail is lowered and secured to the boom, but it removes the need to re-tie the batten ties when you reef or lower the sail.  The bolt keeps the batten in the pocket and  elements the problem of the batten escaping the pocket and chafing the sail.

My batten was loosely tied one day and 'popped' out of the pocket, chafing a hole  through the sail in less than an hour.  While the sail was repaired, I added sail slugs. The ability to easily raise sail and later reef while single-handling has greatly added to my enjoyment of the boat.

I had the same problem as you with the outhaul, but I solved it  by putting a boom cap with an eye attached on the end of the boom, thus giving me the additional boom length to put tension on the mainsail in heavy breezes.   I suspect you might need some instruction from better P-15 sailors than I
as to how to best utilize the outhaul.

Silicone spray in the mast track a few times per season helps with both rope luff and sail slugs. In past, I found Silly cone lets luff rope get dirty and hard to clean... Are you having this problem?

With wax, dirty comes off with a little hydrogen peroxide 50/50 solution with water. How are you getting it cleaned?

I've intsalled the slugs on my 19.  It was recomended to me by the local rigging shop to sew them on with 1/2 webbing, I did. We used the machine for most of them but at the head and tack I had to use the sailors  palm and needle and it was tough, even broke a needle, I would think that with the boat and sail aria being so small that the shackles might not be such a bad idea, I mean far larger boats than ours use the shackles without any trouble.  If you pierce the sail with a soldering iron use a small tip like you would for a chip or other curcuit board work.

Michael P. Barclay
WWP-19 #883 (Corky)
Homestead, Florida

Here are the spacings of the sail slugs on my new WWP-19 Mainsail.  They are measured from the top of the sail in inches"

Slug #:                 1   2    3     4   5    6     7     8     9      10
Inches from top:     5"  27"  51"  74"  98"  122"  146" 169"  193"   216"
Spacings in inches:    22"  24"  23"  24"  24"   24"  23"   24"    23"

The mean spacing is 23.44;  You could use 23.5 and end up with the last one being 0.5" closer to the bottom than on mine or you could get to the same place by reducing the space between the 5th and 6th slugs to 23 and add 1 inch to the space between the 1st and 2nd slugs and get an alternating 23,24 pattern.

I am sure that the spacing is not nearly as important as the quality of the job and making sure they are attached correctly and that the holes are finished off (soldering iron as was suggested might work well, but does the group have any suggestions  as to this method??) such that the sail does not fray or tear under tension.


The Wrinkle Problem at the Large Batten (Nov 97)

From: William Shurr <>
Dear Pottererererers:   Just had my first sail with new sail slugs.  They zipped up and then down with great ease and satisfaction. BUT, a major problem for sail shape: there is a great wrinkle from the leading edge of the large batten down to the clew of the sail. Has anyone run into this? I put two slugs near the head, one on either side of the large batten, about a foot away, and the bolt rope was stretched tight.  Can't think of where I have gone wrong (certainly not in buying a Potter!) Has anyone else run into this problem?  I's appreciate any help you would like to give.

From: Paul Paris <>
We had the same problem(s) after installing slugs on our 19's mains'l. At first I thought that perhaps we had incorrectly attached the slugs, since Rhana and I did the job ourselves.  It turned out, after some experimentation that all that was necessary to remove the slack  in the luff was to apply the proper tension to this part of the sail.  By using the halyard and the downhaul, the latter of which I installed on our boat as it did not come to us with one already, I was able to  get these wrinkles out without a problem.  After that, with the proper trim the main would set beautifully.  In fact, I believe that the sail sets better with the slugs than without.

From: Allen Parks <>
This was exactly our experience with our P-15, "Poteet" ... I installed a boom/clew downhaul at the base of the mast to apply sufficient tension to the luff.  Also, be sure the slugs are above and below the main batten pocket, but that the pocket itself is free to snug in against the mast as necessary. You'll find that with sufficient luff tension, the Potter mainsail will set beautifully .. <!>

Also be sure that you can apply firm "outhaul" tension from the boom end..  otherwise the sail will be too baggy in stiff wind. Ease up this tension for light winds. Having these two tension controls can make a significant difference in sail set for different wind conditions.

Lowering Problems and The Big Batten

From: Rick Hance <hance@FNAL.GOV>
 - -
To P15 sailors with sail slugs,

After much consideration, I finally added sail slugs to my P15.  It didn't turn out the way I had hoped, so I may change it back to original.  But I thought I'd check with "knowledge pool" before I did.  What I did was as follows:

1)  I relocated the mast slot opening to about 6" above the base of the mast.  My intentions being to make it so that everything feeds in from below during rigging. 1) Sail slides, 2) Boom, 3) Down haul cleat.  The down haul cleat I mounted on 1/2" aluminum round stock to act as a stopper to keep everything from falling out when the sail is lowered.

2) I installed sail slugs approximately every 24" along the bolt rope. Everything turned out fine and it works very smoothly EXCEPT -- I cannot lower the main sail all the way without removing the main batten.  Since the batten is full length and it angles upward away from the boom, it cannot be lowered to lay flat along the boom.  The original system worked fine because the bolt rope was removed from the mast slot when lowering the sail.  This allowed the main batten to lie flat.

The reason I installed the sail slugs was to facilitate raising and lowering the sail.  With the original configuration, I would brace myself in the companionway and could work the sail into and out of the slot with two hands.  It was time consuming to raise the sail; but quick to lower it.  With the sail firmly attached to the slides, I will have to get the the batten in/out of the sail while standing in the rear of the cockpit without bracing and working with both hands -- not so good for balance and safety.

Since there are so many P15's with sail slugs, someone must have figured out how to deal with this. So let me have your suggestions please.

From: "Eric Miller" <>
I can't answer your question, but to put this into context (I too am  ready to install sail slugs), normally if the slot were left above the  boom, the _slugs would come out_, as would the batten and it would then  lie flat. The situation you describe sounds like a problem when reefing  (I'm partially through that project now), or when simply dropping the  sail when underway or at the dock. I have been instructed by SailRite to  put a slug about an inch above the batten, and another an inch below, to  allow it to ride better and not bind.  This wouldn't resolve the problem  you have noted. Right?

**Did you attach the slugs with a shackle that lets them to flex?  Or did you fasten them directly and in a fixed position?**

**If the idea is to have the boom and slug slot below the boom so all  doesn't spill out, what if you were to do that, but leave a smaller slot  above through which you could release a slug or two around the batten, but not the boom or all the other slugs?**  Maybe this is too  troublesome.

From:    Bill Zeitler , " Just Wight "
My two cents worth:     My P - 15 # 2060 came with standard bolt rope.  From the WWP Network and also thinking it quite difficult to both thread in the rope and to later drop the sails,  I had a  sailmaker install slugs.  An old  WWP NET comment said " install a slug right at the large batten ".  With slugs [ sewn on with tapes ]  at about 24 inch intervals and the one at the large batten, all was excellent__ except for consideralble binding at the large batten__ !    Further WWP NET discussions led to my removal of the slug AT the batten and placing one about 6" on either side .   Works great !    As to the large batten laying parallel to the boom, I have had no problem.   I just release the halyard and the sail almost drops immediately.  I have never removed the large batten.    The insertion slot is in the " factory " position, all slugs are above the insertion slot, I did lower the downhaul cleat about 4 ",  the last slug is stopped just above the insertion slot with standard sail track stop.   When motoring back to a ramp [ for example ]  the sail  is quickly gathered up and tied to the boom at about 4 or 5 places with stail ties....and the large batten is essentually parallel to the boom.     It all works very well for me.

From: Bert Workman <>
Get slugs immediately!  They will change your life.  I had mine installed by a sail loft, but looking at the job I'm sure I could have done it myself.

They are little plastic attachments that are bolted onto the luff of the sail.  I have about 7 on mine.  On the front of each, attached on a hinge, is a bullet shaped piece that neatly fits into the mast slot.  Once you stick them in the sail feed slot they will run up and down the mast with the greatest of ease.

I'm sure there are different sizes and styles available, and probably different attachment techniques etc.  One thing about placement,  some on the list have complained that having a slug placed right at the end of the main batten cause it to bind because of the pressure from the batten.  My main batten falls between two slugs.

At first I worried about the sail getting pushed out of shape because the batten pushed on it kind of funny.  To solve the problem I simply pull a bit harder on the halyard when I set the sail.  And I have never had a slug bind on me.

Sail Stops
From: Jonathan Myers <>
Then take your new life to Boat US, West Marine, your local chandler and buy a sail stop.  It's a little knurled wheel that tightens down on a kind of blank slug which, when installed in the mast slot properly will keep your slugs from gathering at the gooseneck and running amok.

      Seriously, if you can keep from dropping it, you'll learn to love the little bugger.  It'll allow you to lower your mainsail without dumping it, meaning that you can put it in the "panic drop" mode and not worry about it spilling all over (or off of) the boat.

Moving the Mast Slot (!)

From: Joseph McWilliams <>
> Does the boom go below the slot you feed the sail into?  On my boat, given  the height of the sail, it looks like that's the only way it could go.

This subject came up yesterday when Tom Grimes, Jeff and Sandy Westfall  and myself were on Lake Palestine, Texas, having one of the most wonderful sails I've enjoyed in a long time.

The answer to your question, as both Barry Hall and Lionel Galibert have  pointed out, is yes.  However there is another solution with a different answer.  A solution which I feel is much better if you have sail slugs on  your mainsail.

The way the present slot works, the gooseneck fitting is fed into the  slot and dropped down and the sail slugs are fed into the slot and pushed up above the slot.  In order to prevent the slugs from dropping out of the slot when the sail is lowered, a sail stop is used just above the slot.  This works fine until you need to reef(and reef we did yesterday on Lake Palestine).   When reefing the sail is lowered until the reefing cringle can be secured.  In order to get the reefing cringle low enough the sail stop must be removed, which causes the sail slugs to spill out of the slot.  When the now reefed sail is raised the errant sail slugs above the reefing cringle must be re-fed into the sail slot.  All of this in  wind and wave conditions that warranted reefing in the first place.  The first time I tried to reef my Potter I knew there had to be a better way.

There is a better way.  Move the slot in the mast down to just above the  small cleat at the base of the mast.  This allows you to feed all of the sail slugs and the gooseneck fitting in and up the mast.  The sail stop goes on last, below the gooseneck fitting.  The sail can then be reefed without removing the sail stop.  In fact to reef, you drop the sail, engage the reefing cringle, raise the sail, take up on the reefing outhaul line. Period.  No messing with sail stops or runaway sail slugs while being buffeted by high winds and waves.  The entire process takes seconds rather than minutes, when a minute can seem like an hour.

To move the slot:
1.  With a small hammer, lightly tap the sides of the existing slot until the opening is the same width as the surrounding area.  Use gentle taps, this is more of a finesse that a force. 2. Using a rag over the aluminum to protect the finish, grab the sides of the slot just above the cleat and gently spread the slot.  Again finesse, not force, is called for.  Spread a little, move up, Spread a little, move up, etc.  Do this on both sides until you have an opening wide enough to allow the gooseneck fitting to enter.

A few thoughts:
1.  The sail will set a couple of inches higher than normal.  I haven't noticed that this makes any difference.
2.  Do this only if you have sail slugs.  Without the slugs, you probably want the bolt rope to exit the slot.  Otherwise the gathered sail will prevent you from engaging the reef cringle.
3.  This simplifies the reefing process so much that it will bring a smile to your face every time you reef.


From: Dave Bennett <>
TI've noticed quite a few WWW missives over the past few months regarding slugs (sail slugs, not banana slugs, that infamous mascot of a West Coast
college basketball team!)

Since I sewed a set on the main of my almost-new P-19 recently, I thought I'd add one more message to the archive.

A few things that worked well for me:

 gritted my teeth when it came to punching the hole in the sail for the first grommet. After that it was a less imposing task.

couldn't find a decent waxed thread, so I used waxed dental tape (dental tape is the wider stuff) and a nice, sharp leather needle. Doubled the tape and then sewed--the result is quite strong and helps fight sail plaque as well.

utilized a set of old Kellys (stainless steel surgical clamps) to temporarily hold in place the pieces of nylon strap that now loop twice through each grommet to attach each slug to the sail's bolt rope. Kellys are great for all sorts of things. I swipe them from my wife, a nurse. If you don't live w/a nurse, your friendly family doctor would probably give you an old set or two if you ask.

 o finished off the operation with a glue gun by flowing a layer of hot glue over the waxed thread on each slug to insure that my knots wouldn't slip and the whole thing unravel, thus allowing my main to imitate a spinnaker. Probably not really necessary, but I'm paranoid about  things coming loose on boats.

Hope this is of some help to someone out there.

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