2001 Nacra Inter 20 Restoration - Side Hoop Spinnaker Pole and Hoop Upgrade

Fellow Inter 20 CatSailors!

The boat is currently setup to use the original end-pole spinnaker snuffer design. I'm trying to gather all the parts to upgrade the boat to use a mid-pole snuffer setup. So far I've already found a local metal tubing shop that sells 1.5 OD aluminum tube with .065" wall thickness out of 6063-T6 and is 12 feet long. I found a side hoop snuffer ring off ebay, and I've bought a spinnaker setup with the patches setup for a side pole hoop. I've also found and bought a side hoop spinnaker sock made by performance sails.

The remaining items I need to find and figure out are:

1. The aluminum pole is raw and non-anodized. I've searched high and low trying to find a local source for a sunfish upper boom, and I've tried to order a new one off of the internet, but the freight shipping cost of a single boom makes it un-economical to order a single anodized pole. For the other Inter 20 folks who have made this swap do most folks find an anodized pole or do they paint them? Pay to anodize them? Or get the pole powder coated? I'm pretty sure the pole will oxidize pretty quickly if I leave it raw and primarily sail the boat in the ocean.

2. Does anyone have the dimensions conveniently available on what distance from the front cross beam the side hoop should mounted on the new spinnaker pole? I can make a guess based on the length of the sail sock, but I'd love a dimension from someone who has their side hoop setup sweet.

3. The end-pole plastic fitting that inserts onto the bracket mounted to the front crossbeam, is that a standard Nacra part I can order for the aluminum pole? I can machine one out of nylon at work, but that will take extra work and if I can simply order a part of the internet that is likely the fastest solution to get setup

4. On the bridle wires-spin pole bracket, my current bracket is sized for a 2" OD Carbon pole. Is there a similar standard Nacra part that replaces the old bracket for a pole with a 1.5" OD? I thought about machining a spacer to accommodate the new pole in the old bridle bracket, but I'm guessing this is also been previously solved.

5. Lastly, the current end pole snuffer is setup with a common spinnaker halyard that is also the snuffer retrieval line. There are a number of blocks and bungees under the tramp that I'm pretty sure are setup to route this halyard/snuffer line, but I haven't been able to figure out the rigging of running this line so that the bungees suck up the slack in the line. I've looked online and through the original I20 assembly manual, but I couldn't find anything. Anyone have a simple drawing or series of pictures that shows how to route the halyard under the tramp?

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Erik Lassen
Monterey, CA

Resurrecting's a Semi Neglected Nacra Inter 20 to Sail and Race with the Kids!
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For corrosion control consider Alodine:
https://www.aircraftspruce.com/catalog/cspages/alodine1001.php?clickkey=11999

Followed up with paint it should last.

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Bryan in Poplar Grove, IL
Supercat 17, unknown year. Future project
Hobie 16, 1977 - died a spectacular death https://youtu.be/Y7O22bp2MVA
Hobie 16, 1978 - current boat
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Here are some quick answers.
1. I would recommend alodine or bonderite M-CR 1201. This is an aluminum conversion coating using a chemical to convert the aluminum to corrosion-resistant. It is almost as good as anodize and a standard pre-requisite to painting raw aluminum for aircraft parts if they are not anodized. About $35 per quart from Aircraft Spruce or Amazon.

2. I will give you the dimension for mine by next weekend. I positioned the hoop to accommodate a bag 110" long and to rig similar to current F18s. The back of the bag is now about a foot behind the front beam. The snuffer grommet is next to the mast rotator grommet on the trampoline. Different grommets had to be added to my old spinnakers so they would fold smaller to fit in the shorter bag. The bag went from 12' long (the length of the entire pole) to just over 9'. Are you planning to have your old bag run under the entire trampoline? I have no experience with this.

3. You can order a part. A dealer can help you with this. New England Catamarans and Murrays are always helpful.

4. I cut the loop off the bridle and sailed all summer with a dyneema loop holding the pole up towards the bridle. The loop was attached to the forestay chainplate. The pole bridle tension on the end of the spinnaker pole will maintain the pole pre-bend. I am incorporating a compression rod off the bridle to replace the loop (same as the carbon 20). I will send you photos if you want?

5. I have a 2000 boat. At the time, spinnakers were launched off bags on the tramp. The tack line was connected to the halyard. When the halyard was pulled, the spinnaker tack automatically went to the end of the pole. You can see an example in the new Nacra Evolution assembly manual on the Nacra site. With your end pole snuffer, this became a moot point. I have a separate tack line based on microwindracing.com

You will find detailed drawings at the above site. The bungee that tensions the snuffer line also keeps my tack line tight. When the tack is tight (chute up) the slack loosens the snuffer end of the halyard. I can provide photos and I20 dimensions at a later date, as I dis-assembled the system and boxed everything for the winter.

Hope this helps?

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David
Inter 20
Southern Maine
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I built my I20 spin pole from bare alluminum four years ago. I sail in the ocean and it has not reacted noticeably. Snuffer sock should end about three inches before dolphin striker bar. You may be able to buy the nylon fitting from Murrays. It is a standard part. Pole diameter should be smaller than bracket diameter. Mine is. Tension from pole stays induces prebend into the pole and keeps it from moving around in the bracket. Bracket needs to be larger than pole so pole can slide in (pole has jam cleat on rear end to set jib car traveler range on self-tacker). Retrieval line runs from top patch of spin, through other patches, into hoop, out through ring at rear of snuffer bag, through grommet in tramp (about two feet behind mast; runs from under tramp to above tramp), to turning ring on bungee at rear of tramp (various ways to set up bungee takeup), then to cleat (often spinlock) on forward beam, through turning block, and finally up mast, turning block, and to spin head. A neat thing is if you don't use a separate tack line you can run the setup without a bungee.



Edited by traphappy on Jan 04, 2021 - 12:08 AM.
There are many ways to rig this boat, especially with the spin setup (including spin sheet), the mast rotation, active downhaul, and the jib rigging.

As for #4, keep the loop that you have. It works great and provides the means to rig other things rather than drilling the spin pole and adding unnecessary hardware. . . . and you can order stock forestay bridals. There will be no play with the 1.5" spin pole once it is rigged and pre bent.

No reason you can't find a used sunfish spar. The are everywhere, especially small local sailing clubs.

Here are some links in my album that will help you think through this and give you some ideas.
https://www.thebeachcats.…cb29f216e3dd323f53d385e1

https://www.thebeachcats.com/gallery2/main.php?g2_view=core.DownloadItem&g2_itemId=131837&g2_serialNumber=4

https://www.thebeachcats.…2_itemId=18279&g2_page=1

Disclaimer: This boat was/is well designed out of the box and extremely well balanced for an One Design factory boat. It has evolved with upgrades through the years that were nice . . . mid pole snuffer, self tacker, improve rudders (gen 2), improved rotator, etc. No need to try to redesign it. The focus should be on the details with the rigging, and you have a lot of options.

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Philip
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Not meaning to hijack this thread, but looking at your pics, you have one titled "5 year paint" showing a very clean boat/paint job (appears durable). What paint did you use on that boat? I'm about to redo mine in the next few weeks.

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Chuck C.
H21SE 408
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The problem with an unanodized pole is you can't protect the inside. Water gets on the inside of the pole and will corrode the pole from the inside-out. Traphappy, I would check your pole. I have seen corrosion buildup on anodized poles; not a worrying level, but I would expect a lot more on a 5 year old non-anodized poles.

As to sources beyond the sunfish spar:
1) East coast I usually buy from Red Gear Racing, they stock in 24' blanks
2) Rig Rite in Rhode Island also stock longer 1.5" O.D aluminum tubes
3) Murrays on the West Coast certainly have tubes.

I always drive or have them driven..shipping is too expensive.
charlescarlisNot meaning to hijack this thread, but looking at your pics, you have one titled "5 year paint" showing a very clean boat/paint job (appears durable). What paint did you use on that boat? I'm about to redo mine in the next few weeks.


Pettit Paints on the 5.8NA, designed to brush on. That's not the same boat. Some pictures are the 5.8NA (Pettit Paints), and some are a factory gelcoat yellow N20.

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Philip
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P.M.
charlescarlisNot meaning to hijack this thread, but looking at your pics, you have one titled "5 year paint" showing a very clean boat/paint job (appears durable). What paint did you use on that boat? I'm about to redo mine in the next few weeks.


Pettit Paints on the 5.8NA, designed to brush on. That's not the same boat. Some pictures are the 5.8NA (Pettit Paints), and some are a factory gelcoat yellow N20.


and to confirm to the keen observer, the 5.8 is a yellow boat to starboard and a white boat to port!
icon_confused

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Philip
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samc99usThe problem with an unanodized pole is you can't protect the inside. .

You can alodine the inside of the pole as easy as you can anodize the inside of it.

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Bryan in Poplar Grove, IL
Supercat 17, unknown year. Future project
Hobie 16, 1977 - died a spectacular death https://youtu.be/Y7O22bp2MVA
Hobie 16, 1978 - current boat
--
waiex191
samc99usThe problem with an unanodized pole is you can't protect the inside. .

You can alodine the inside of the pole as easy as you can anodize the inside of it.


Sure. You can also source an anodized pole more easily than applying alodine or anodizing a bare Aluminum one.



Edited by samc99us on Jan 08, 2021 - 11:08 AM.
P.M.
P.M.
charlescarlisNot meaning to hijack this thread, but looking at your pics, you have one titled "5 year paint" showing a very clean boat/paint job (appears durable). What paint did you use on that boat? I'm about to redo mine in the next few weeks.


Pettit Paints on the 5.8NA, designed to brush on. That's not the same boat. Some pictures are the 5.8NA (Pettit Paints), and some are a factory gelcoat yellow N20.


and to confirm to the keen observer, the 5.8 is a yellow boat to starboard and a white boat to port!
icon_confused


Not anymore it ain't, bro!

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Jerome Vaughan
Hobie 16
Clinton, Mississippi
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samc99us
As to sources beyond the sunfish spar:
1) East coast I usually buy from Red Gear Racing, they stock in 24' blanks
2) Rig Rite in Rhode Island also stock longer 1.5" O.D aluminum tubes
3) Murrays on the West Coast certainly have tubes.

I always drive or have them driven. Shipping is too expensive.


No issue with driving a couple of hours to pick up a sailboat part.

Thanks for all the discussions and ideas. I've been searching high and low for a local sunfish spar and so far I haven't found anything in the Bay Area, Santa Cruz, Central Coast or Central Valley. Given all the sailboats around these parts I'm suprised!

I work for an aerospace company, but we primarily deal with Carbon composites and some aluminum. I talked to one of our vendors who is a local tube shop and I can buy a raw aluminum in a 20' foot stick with the correct grade, temper, and dimension for about $100 delivered to work, but to have a single stick that sized anodized is 3-4 times the cost of the tubing. The anodizing setup cost is about the same if I do one or if I get a batch of them anodized, so if I order 10 and get them anodized then the per isn't too bad, but then I got to sell off 8 more to come out ahead, so its really not cost effective to anodize a single stick.

Also as a note for folks who are trying to do the same thing, you basically are buying a 20' stick no matter what length you are going to order if you want the best price and then the shop will cut it to length for you, so you don't really get a "per foot" cost but rather a 20' cost and you get to choose if you want to have it cut for you and its almost the same price whether you decide to keep the dropped piece.

- Sunfish Direct has the upper boom without fittings for $129, but the shipping from east coast is ~$400

- Murrays doesn't have the blank anodized tube.

- Rig-Rite I've tried to contact via phone, fax and email, and I have probably left 6 or 7 voicemails and even paid to send a fax order in, but I'm assuming they are out of business because they wont ever respond to my voice messages and fax.

Right now my best local find is to buy an old 2 piece tapered carbon windsurfing mast from a friend and try to set it up with the side snuffer hoop. I'm concerned that using stainless pop-rivets or machine screws to attach the bridle fittings will be sort lived due to the galvanic potential between the stainless and carbon. If I go with the carbon-stainless setup, I'll plan on wet setting the stainless hardware to try to isolate the galvanic potential between the carbon and the fittings.

I'm also a little concerned about the localized "bearing" loads of the hardware into the carbon mast's thin wall. I know metals are much better at point loading small concentrated bearing loads. I've been looking for a cleaver soft rig/dynema lashed fitting concept for the end of the pole, but I haven't found one yet. I'm guessing there are already a clever cat sailors out there who have already solved this, so If anyone has a picture or clever way to rig the end of a two peice carbon windsurfing mast I'd love to see it!



Edited by rocketboy52 on Jan 15, 2021 - 06:51 PM.

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Erik Lassen
Monterey, CA

Resurrecting's a Semi Neglected Nacra Inter 20 to Sail and Race with the Kids!
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Four seasons, $17 bare AL pole going strong. Looks beautiful with no signs of corrosion.
I vaguely remember a thread on Catsailor from 10 or so years ago about using a windsurfer mast for a pole.

Happy hunting!
With a tennis racket for a hoop.
In response to your galvanic corrosion comment: Look at your carbon mast- this stainless hardware is likely in good shape after 20 years of stainless steel and carbon (particularly inside the mast). The galvanic concern is a major problem with carbon and aluminum, but not as much with SS. If this concern still keeps you up- titanium screws and rivets put the issue to bed.

I have used a carbon pole for many years. It is 2" without the taper- similar to a windsurfing mast base diameter. This was first purchased in the 1990s and sailed on a Nacra 6.0 for many years

Last summer I started using this same pole on my I20. The pole length for the 6.0 was 14', while the I20 length is 12'. The 6.0 chute was much larger- going all the way back to the rear beam. After sailing all summer I believe the 2" straight carbon pole is overkill for the I20.

Because of the length issue mentioned above, and my hesitation to cut a perfectly good tube, I riveted the tack pulley to the pole. Halfway through the season- the tack pulley ripped out of the pole during the NE100 race in the heavy wind while trapezing with the spinnaker up. I then replaced the tack eyelet rivets with nuts and bolts and have not had a problem. I cut the tube for easy wrench access. All of the other cleats and eyelets are fine with rivets. This other hardware on the pole does not have the high loads the sail tack had. They are also bearing or shear loaded rather than in a tensile (tear-out) direction.

New boats use 1.25" or 1.5" diameter (approximate) aluminum spinnaker poles. Carbon is much stronger than aluminum. If you can find the skinny windsurfer masts- these would work also. There is no need the pay the price for 2" diameter aluminum or carbon- you are paying for overkill.

I build side hooks for the spinnaker pole similar to AHPC or the SNU setup for multiple pole diameters. Send a note if you are interested as a fellow I20 sailor?

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David
Inter 20
Southern Maine
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traphappyFour seasons, $17 bare AL pole going strong. Looks beautiful with no signs of corrosion.


You forgot to tell them how much that bare aluminum pole hurts when it slams into the shins of your crew while peter-panning on the wire when the skipper hits a sand bar at 20kts. Glad you were able to save a few bucks over carbon though. icon_lol Carry on with discussion.



Edited by CatFan57 on Jan 17, 2021 - 11:03 PM.

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1998 P18.2 "Powda"
Sailing out of SHBCC, NJ
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I'm Looking to start cutting and drilling the 2 piece tapered, carbon windsurfing mast I got from a friend at work for free. With it being free I figured, might as well give it a try. Older Neil Pryde mast.

Does any one have the dimensions from the front cross beam to the center of the hoop handy? I can eye ball it from pics on the web, but if someone knows the commonly used dimension by those who have already done this upgrade that would be helpful.

I found side pole spin bag from BNR In the Netherlands, those guys are great by the way!Shipping was quick and reasonable from Europe to CA!

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Erik Lassen
Monterey, CA

Resurrecting's a Semi Neglected Nacra Inter 20 to Sail and Race with the Kids!
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90 inches. BTW Catfan57 loved every second of our Peter Pan rendezvous at the front of the boat!
traphappy90 inches. BTW Catfan57 loved every second of our Peter Pan rendezvous at the front of the boat!


Yeah, I'd say the "rendezous" at the $17 bare aluminum spin pole verified it was/is in fine shape and not corroded in the least, considering it came out completely unscathed. But my 195 lbs, hitting it at full force, probably would have been enough to prove the point - not so sure the pole, or my shins, needed an extra 225 lbs (being generous here) slamming in right behind to verify the experiment. But sure glad to know you're meticulous about testing out your equipment - so you can report the results on thebeachcats. icon_wink



Edited by CatFan57 on Jan 29, 2021 - 10:12 AM.

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1998 P18.2 "Powda"
Sailing out of SHBCC, NJ
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Hey, Catfan57, what is the word on the Statue Race this year? Is there a date yet?

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dk

Blade F-16
Hobie Tiger
Hobie 14
Corsair F-242
Mirage 25
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Hey dssaak. While I haven't spoken directly to any of the club officers about it, recent emails from them say that they hope, and in fact are planning, for the club to be back to functioning normally this year, with full sailing activities. So they have posted the club's calendar (see here: http://www.fleet250.org/cgi-bin/calendar.cgi) with full activities, including that they are showing the 2021 Statue race scheduled for 7/4/2021, with a makeup date of 7/5/2021. So I think the best I can say is that the club officers are planning for the race, along with all other planned activities. But obviously that assumes we don't get "the man" coming down on us and disrupting plans based on some covid crap. I hope that answers the question as best as possible. Basically, I'd say plan on it, but stay in touch in case some douche bag in authority brings down the hammer beyond our control.



Edited by CatFan57 on Jan 29, 2021 - 10:13 AM.

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1998 P18.2 "Powda"
Sailing out of SHBCC, NJ
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So I've made some progress on getting a Carbon Windsurfing Mast Setup as the a side pole snuffer. I tried to use most of the same hardware from the stock pole, but I'm looking for a couple more details, images and advise on the following:

1. Any good advice on how setup the tack/halyard line pully at the end of the pole. With the stock pole the sail is just shackled right to the stainless hoop on the end of the pole, but in a lot of the F18 pictures I've found there is a separate tack line that is also continuous to the halyard with bungies that take up the slack? I'm trying really hard to figure out how all the works and where the lines all run.

In the pictures below, if you click on the pic, it will show you the full size image.

Original End pole hardware
https://www.thebeachcats.com/gallery2/main.php?g2_view=core.DownloadItem&g2_itemId=134561&g2_serialNumber=3

One option for the hardware at the end of the new pole?
https://www.thebeachcats.com/gallery2/main.php?g2_view=core.DownloadItem&g2_itemId=134555&g2_serialNumber=4

2. What angle should the snuffer hoop set at relative to the horizon? (Red lines in the pic Pic)
https://www.thebeachcats.com/gallery2/main.php?g2_view=core.DownloadItem&g2_itemId=134552&g2_serialNumber=4

3. On some of the newer F18 boats I see a little support line that supports the snuffer hoop. Is that typically used (blue line in the above pic) How does the blue line attach to the snuffer pole? Currently the side hoop sock has no attach points to receive a line.

4. Does the Spin sock rear attach via bungies to the dolphin striker? Obviously I need to repair the top bungy that has previously snapped with the original owner
https://www.thebeachcats.com/gallery2/main.php?g2_view=core.DownloadItem&g2_itemId=134572&g2_serialNumber=4

https://www.thebeachcats.com/gallery2/main.php?g2_view=core.DownloadItem&g2_itemId=134575&g2_serialNumber=4

After looking at all my current setup and fit check pics, if anyone sees something totally wrong or dumb, please let me know or point me to a picture of the right way to setup/rig a side pole hoop. The album of photos is uploaded to the Beachcat Photos page here:

https://www.thebeachcats.…ictures?g2_itemId=134490

Original Pole
https://www.thebeachcats.com/gallery2/main.php?g2_view=core.DownloadItem&g2_itemId=134528&g2_serialNumber=4

Laying out the new pole
https://www.thebeachcats.com/gallery2/main.php?g2_view=core.DownloadItem&g2_itemId=134534&g2_serialNumber=4

First Fit Check
https://www.thebeachcats.com/gallery2/main.php?g2_view=core.DownloadItem&g2_itemId=134537&g2_serialNumber=4

Old pool Vs New Pole end elevation
https://www.thebeachcats.com/gallery2/main.php?g2_view=core.DownloadItem&g2_itemId=134540&g2_serialNumber=4

Bridle elevation difference
https://www.thebeachcats.com/gallery2/main.php?g2_view=core.DownloadItem&g2_itemId=134543&g2_serialNumber=4

Side Hoop Offset from the Front Cross Beam
https://www.thebeachcats.com/gallery2/main.php?g2_view=core.DownloadItem&g2_itemId=134546&g2_serialNumber=4

Popping Some Rivets
https://www.thebeachcats.com/gallery2/main.php?g2_view=core.DownloadItem&g2_itemId=134549&g2_serialNumber=4

Another End-pole Hardware detail shot
https://www.thebeachcats.com/gallery2/main.php?g2_view=core.DownloadItem&g2_itemId=134558&g2_serialNumber=4



Edited by rocketboy52 on Apr 11, 2021 - 12:13 AM.

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Erik Lassen
Monterey, CA

Resurrecting's a Semi Neglected Nacra Inter 20 to Sail and Race with the Kids!
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I found this picture in the Nacra F18 Assembly Manual that shows a support line that goes from the bridle tang to the side snuffer hoop, but no details or close up on how the side snuffer hoop is attached to the line. Anyone got a close up shot of how the line attaches to the hoop?

https://www.thebeachcats.com/gallery2/main.php?g2_view=core.DownloadItem&g2_itemId=134588&g2_serialNumber=4

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Erik Lassen
Monterey, CA

Resurrecting's a Semi Neglected Nacra Inter 20 to Sail and Race with the Kids!
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Here is how I have the new Spin pole supported under the old style bridle bracket. Does anyone have a more elegant solution then this, or is this good with enough pre-load on the bridle lines to keep pole snugged up against the "soft loop"?

https://www.thebeachcats.com/gallery2/main.php?g2_view=core.DownloadItem&g2_itemId=134592&g2_serialNumber=4



Edited by rocketboy52 on Apr 11, 2021 - 05:26 AM.

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Erik Lassen
Monterey, CA

Resurrecting's a Semi Neglected Nacra Inter 20 to Sail and Race with the Kids!
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Hoop angle is correct. You may attach support line in one of two ways: 1) tie to pole just forward of hoop and tuck line into hoop groove. 2) drill hole in hoop and secure line by tying a knot inside.

The spin pole should run through the bridle ring. The correct elevation at the tack, and steadiness in the pole, is achieved by applying tension to bridle lines and bend into the pole.

The fittings at the end of the pole should be clean to avoid ripping the spin.

The the loop in the back of the spin sock is not for attachment to the dolphin striker. It is for the spin retrieval line to pass through. This prevents the spin from being pulled out the back of the sock. Sock attaches to boat via grommets in rear corners.

There are multiple ways to rig the tack and retrieval lines. You can rig it so the tack comes out or snuffs automatically. An advantage of this setup is that if line lengths are correct, the retrieval line does not need to loop to the back of the trampoline. Much cleaner tramp.



Edited by traphappy on Apr 11, 2021 - 12:00 PM.
I am updating the pole on my I20 to have a bit less pre-bend. The hardware used on the current Nacra 18 and 20 work nicely. I will provide part numbers if you message me. 5/8 aluminum rod is used. The pole will be tied to the bridle mounts for additional stability.https://www.thebeachcats.com/pictures?g2_itemId=134598 https://www.thebeachcats.com/pictures?g2_itemId=134595

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David
Inter 20
Southern Maine
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Hello, like you I’m restoring an Inter 20 (in Scotland) having owned one ages ago (fantastic boats). Would anyone by any chance know what the length of the spinnaker pole is supposed to be? The boat I have purchased has half a pole, which in my experience is a common phenomenon! Thank you, Jamie
jamiebHello, like you I’m restoring an Inter 20 (in Scotland) having owned one ages ago (fantastic boats). Would anyone by any chance know what the length of the spinnaker pole is supposed to be? The boat I have purchased has half a pole, which in my experience is a common phenomenon! Thank you, Jamie


Jamie! They are sweet boats! They can float me and a bunch of kids, its great.

I cut my new windsurfer mast to match the length of the original end-pole snuffer setup. The Spin pole is 143 inches long, and the spinnaker tack pully is mounted 1.5 inches from the end of the pole, so its at 141.5" from the cross beam.

What all are you doing to "restore" your I20?

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Erik Lassen
Monterey, CA

Resurrecting's a Semi Neglected Nacra Inter 20 to Sail and Race with the Kids!
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