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fixed carbon bowsprit


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#1 golfinaspen

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Posted 27 November 2012 - 10:55 PM

Interested in adding a fixed carbon bowsprit to my Ben 25 (platu). We have been flying assym's from the pole with good results, especially in light air, but a sprit would make sail handling much simplier given the tippy nature of the boat when it blows. Does anyone know who makes such custom equipment?

#2 Vela Sailing Supply

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Posted 28 November 2012 - 03:41 AM

Assuming that you want to keep the option of sail the boat under One Design configuration with too much hassle, I suggest to install a Forte Carbon bowsprit. They are simple and easy to install, as well as remove when you want to bring the boat back to its original layout. For a boat like the Platu 25, a 2" ID carbon sprit will do the trick. The way Forte builds this tubes oriented for use on a 50/50 ratio (supported/unsupported lengths): ie. If you want a 3 ft bowsprit from the stem to the tip, then you need a 6 ft. tube. Keep in mind that this sprit will work for an asymmetrical spinnaker not for a code zero (you need to add a bobstay for a code zero to compensate for luff rope/halyard tension).

Here are some shots of how it looks like:

Posted Image Posted Image

We carry the small kit at $1,559 including:
• Carbon sprit painted clear.
• Harken loop and outboard cap.
• Your choice of aft mount: Saddle or removable deck eye.

Feel free to email or call us if you want to talk about this and the options.

Rod

#3 golfinaspen

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Posted 28 November 2012 - 03:51 AM

Boat is not in OD configuration as it sails PHRF and there is no OD competition in the U.S. It uses assym chutes carried on the OD pole which greatly improves handling and reaching performance. Replacing the pole with a fixed sprit is the concept.

#4 golfinaspen

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Posted 29 November 2012 - 05:03 PM

Found it, GC Marine in Richmond CA made a custom fabrication for a sister ship. Check out www. gcmarine.net and the showcase tab for details. Looks like a beautiful job.


#5 sos

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Posted 20 December 2012 - 08:08 PM

Found it, GC Marine in Richmond CA made a custom fabrication for a sister ship. Check out www. gcmarine.net and the showcase tab for details. Looks like a beautiful job.



I've sailed that boat. Worked really well and I can't speak highly enough about Gills, great guy and dose great work

We found you can use an M24 kite quite well.

#6 Ryley

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Posted 21 December 2012 - 01:14 AM

Don't know where you sail, but before you make the mod you may want to check with your PHRF committee. In PHRFNE, they are looking at boats that have added a fixed sprit and asyms and made the length such that they don't take a rating hit. The formula for adding a fixed sprit to a racer/cruiser is +9 minus 3 per 10% J or fraction increase

Some boats increased their J on the pole to cancel out the +9 and remain at the same rating they had, despite an incredible increase in downwind sail area. The situation is currently under review, there will be changes coming, and they've already said it will apply not only to boats that make the change in the future but boats that have already made the change.

#7 Soley

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Posted 21 December 2012 - 03:59 PM

I assume you are ready to buy new kites as well as buying the sprit as your current assyms will not work too well on the new configuration.

If melges 24 kites fit that would be very nice! Have you thought about going the retractable pole route? You could have two settings, half pole out for A3 and full pole out for A2 and A1. It maybe less expensive to retro fit the boat for that.

#8 golfinaspen

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Posted 23 December 2012 - 12:58 AM

SOS please tell me more about the performance of Black Sheep with the sprit. I seems that M24 sails would be too long on the luff. Gilles thought that a shorter sprit would well and not need a bob stay especially sice we now lead the tack line down and under the deck via a bolt hole in the forestay chain plate on the bow.

Solely, we have considered a retractable pole but the internal reinforcement of the tube would be considerable since the boat is quite skinny up front . A fixed sprit is a straightforward solution. The LIS PHRF. Committee uses a similar rating formula based on TSP/J and a sprit about 3.9 feet would allow the boat to sail at the bareboat 120 rating. I think Black Sheep has sprit about a foot longer. We will need a new runner but the existing reacher would still work.

The Platu is a giant killer in light air but when the breeze picks up it is a handful downwind so getting rid of the pole is a project worth exploring. We have also followed with Interest the development of the Donovan GP 26 as another horse for the course on Long Island Sound.

#9 garrett818

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Posted 23 December 2012 - 04:24 AM

One thing to keep in mind: In heavyer air a longer sprit will balance the boat better than a short one.

#10 Ryley

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Posted 24 December 2012 - 03:51 AM

SOS please tell me more about the performance of Black Sheep with the sprit. I seems that M24 sails would be too long on the luff. Gilles thought that a shorter sprit would well and not need a bob stay especially sice we now lead the tack line down and under the deck via a bolt hole in the forestay chain plate on the bow.

Solely, we have considered a retractable pole but the internal reinforcement of the tube would be considerable since the boat is quite skinny up front . A fixed sprit is a straightforward solution. The LIS PHRF. Committee uses a similar rating formula based on TSP/J and a sprit about 3.9 feet would allow the boat to sail at the bareboat 120 rating. I think Black Sheep has sprit about a foot longer. We will need a new runner but the existing reacher would still work.

The Platu is a giant killer in light air but when the breeze picks up it is a handful downwind so getting rid of the pole is a project worth exploring. We have also followed with Interest the development of the Donovan GP 26 as another horse for the course on Long Island Sound.


Yeah, but what I'm saying is that that formula is going to change in PHRFNE because they've determined that it gives far too much advantage to the people who make that conversion. If PHRFNE changes, expect it to affect ECSA and PHRFLIS as well, if not next year then within a couple years. Bear in mind that the change, when they announce it, will be applied to existing changed boats as well - no grandfathering.

#11 golfinaspen

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Posted 24 December 2012 - 07:11 PM

Garrett818 - good point, center of effort of the sailplan moves forward something that we have considered but not with precision. At the moment we are looking to get the length and new sail area into a band that does not hammer the rating the way the pole + asyms do and give us an improvement in boat handling.

Ryley - agree, no doubt the local PHRF committees look to each other for solutions to "loopholes". The interesting point is that LIS uses the same rating criteria for both fixed sprits and retractable poles so long as the chute is tacked on the centerline. PHRF LIS also has a multi-part screen for chute size so one possibility could be to tax heavily based on sail size, primilary mid-girths on runners and not so much sprit length. One would think that the handicappers have sufficient data with the J boats of various sizes but the conversions are one-offs, hence the issue. I think we are with a band of =/- 6 sec/mi and would live happily in that range if we get a boost in handling. One screwed up jibe with the pole eats up that delta very fast.

#12 golfinaspen

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Posted 17 April 2013 - 01:27 AM

IMG_0524_small.jpg

 

Here is picture of the GCMarine sprit for Black Sheep before it was fitted to the boat.

here is the business end.

IMG_1118_small.jpg

Still considering a similar setup but probably more of a TP52 type sprit since we need only one jack line.



#13 clamslapper

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Posted 18 April 2013 - 08:35 PM

Assuming that you want to keep the option of sail the boat under One Design configuration with too much hassle, I suggest to install a Forte Carbon bowsprit. They are simple and easy to install, as well as remove when you want to bring the boat back to its original layout. For a boat like the Platu 25, a 2" ID carbon sprit will do the trick. The way Forte builds this tubes oriented for use on a 50/50 ratio (supported/unsupported lengths): ie. If you want a 3 ft bowsprit from the stem to the tip, then you need a 6 ft. tube. Keep in mind that this sprit will work for an asymmetrical spinnaker not for a code zero (you need to add a bobstay for a code zero to compensate for luff rope/halyard tension).

Here are some shots of how it looks like:

image_bowsprit01.jpg image_bowsprit02.jpg

We carry the small kit at $1,559 including:
• Carbon sprit painted clear.
• Harken loop and outboard cap.
• Your choice of aft mount: Saddle or removable deck eye.

Feel free to email or call us if you want to talk about this and the options.

Rod

 

 

Makes the foredeck look pretty nasty. 



#14 Left Hook

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Posted 20 April 2013 - 07:19 PM

IMG_0524_small.jpg

 

Here is picture of the GCMarine sprit for Black Sheep before it was fitted to the boat.

here is the business end.

IMG_1118_small.jpg

Still considering a similar setup but probably more of a TP52 type sprit since we need only one jack line.

That is sexy as all hell...



#15 golfinaspen

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Posted 13 November 2013 - 09:59 PM

Here is a picture of the sprit mounted on the bow of Black Sheep, looks great.  We will build a TP52 style sprit with a single tube using a single tack line that exits the sprit and then goes  through the stem head and aft below to cam cleat mounted on the companionway ladder. This will keep the deck clean and allow the pit person to operate without shifting position.

Attached Files



#16 Christian

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Posted 13 November 2013 - 10:52 PM

Seriously????????????????   that is a more than average clumsy solution - and about half the length needed.  Come on you know better Rod!

Assuming that you want to keep the option of sail the boat under One Design configuration with too much hassle, I suggest to install a Forte Carbon bowsprit. They are simple and easy to install, as well as remove when you want to bring the boat back to its original layout. For a boat like the Platu 25, a 2" ID carbon sprit will do the trick. The way Forte builds this tubes oriented for use on a 50/50 ratio (supported/unsupported lengths): ie. If you want a 3 ft bowsprit from the stem to the tip, then you need a 6 ft. tube. Keep in mind that this sprit will work for an asymmetrical spinnaker not for a code zero (you need to add a bobstay for a code zero to compensate for luff rope/halyard tension).

Here are some shots of how it looks like:

image_bowsprit01.jpg image_bowsprit02.jpg

We carry the small kit at $1,559 including:
• Carbon sprit painted clear.
• Harken loop and outboard cap.
• Your choice of aft mount: Saddle or removable deck eye.

Feel free to email or call us if you want to talk about this and the options.

Rod



#17 rantifarian

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Posted 14 November 2013 - 03:40 AM

Seriously????????????????   that is a more than average clumsy solution - and about half the length needed.  Come on you know better Rod!

 

If OP wants to have it easily removable, cheap, etc, it isnt a terrible option. We used a similar setup alloy dick on our trailer sailer to fly the 48m^2 chicken chute when it was averaging above 25 and couldn't use the rotating pole for the bigger chutes. As he said in the note, it is designed for a 50/50 length ratio, so just buy the size you need.

What is wrong with it?



#18 Christian

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Posted 14 November 2013 - 07:30 AM

It is a honking big monstrosity built for a 35 foot cruiser - not a 25 foot almost-sportboat

 

Seriously????????????????   that is a more than average clumsy solution - and about half the length needed.  Come on you know better Rod!

 

If OP wants to have it easily removable, cheap, etc, it isnt a terrible option. We used a similar setup alloy dick on our trailer sailer to fly the 48m^2 chicken chute when it was averaging above 25 and couldn't use the rotating pole for the bigger chutes. As he said in the note, it is designed for a 50/50 length ratio, so just buy the size you need.

What is wrong with it?



#19 schoonerman

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Posted 14 November 2013 - 02:50 PM

I always have like this option for adding a sprit. Happens all the time on SC52's. The tip of the spin pole lives in the outer collar and simply slides out to fin in the more forward deck chock. This also doubles as the Sym Pole. Obviously you have to reinforced the crap out of the pole (should/must be carbon)



#20 Foilman

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Posted 03 April 2014 - 06:38 PM

IMG_0524_small.jpg

 

Here is picture of the GCMarine sprit for Black Sheep before it was fitted to the boat.

here is the business end.

Attached File  CCI_C&C115_Bowsprit_2.JPG   221.23K   22 downloads

 

A shorty we just made for a C&C 115

 

Phil



#21 golfinaspen

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Posted 05 April 2014 - 05:23 PM

We made the decision to have GC Marine build a sprit for our Platu 25, First Tracks.  The sprit will be shorter than the one they designed for Black Sheep so that we fit within a rating band on LIS for fisprits.  It will be 3.33' so that TPS = 11.9.  This should result in no change for the distance rating ( 114) but improve the W/L by 6 sec/mi to 120.

 

The design will closer to a TP 52 style with a G10 plug at the outer end for the jackline to exit. Since the boat used asymmetrical chutes off the pole and the jackline ran under the deck, this configuration will match well. Attached is a picture showing the jackline entering the bow. We eliminate the pole, foreguys and afterguys that should make jibing much easier.

 

The band has been made using Black Sheep as a "mold" and fitted to our bow. See picture of the band in frame. Differences in dimensions were noted and will be  taken into account when the sprit fabricated.

 

Gilles is now in the process of  finalizing the design and construction will shortly commence.

Attached Files

  • Attached File  bow.jpg   61.68K   29 downloads


#22 golfinaspen

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Posted 05 April 2014 - 06:16 PM

The first picture shows the band after it was removed from Black Sheep.  The frame is needed to maintain stability and the geometry. It was shipped to us and fitted to the bow of our boat - picture 2. We, measured the differences in dimensions, both sides and also marked the location of the exit hole in the bow so that the tackline path can be ascertained and incorporated into the design .

 

A new VMG A1 chute has been ordered from Quantum.

Attached Files



#23 golfinaspen

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Posted 15 April 2014 - 07:00 PM

Attached are pictures of the sprit being laid up, vacuum bagged and the result. Reinforcement, joining to the band and finishing are the next steps. 

Attached Files



#24 SoAPieceOfStringWalksIntoABar...

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Posted 16 April 2014 - 01:32 AM

Did a couple fixed sprits a few years ago, here's how the bigger one went together:

https://picasaweb.go...412600420980721

#25 SoAPieceOfStringWalksIntoABar...

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Posted 16 April 2014 - 03:18 PM

Attached File  DSCF0776.JPG   195.23K   25 downloads

 

ugh, bad link. this one works:

https://picasaweb.go...it?noredirect=1



#26 tootall519

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Posted 16 April 2014 - 07:48 PM

Too short. should go 4' to 4.5' out from J is you want to go downwind.



#27 SoAPieceOfStringWalksIntoABar...

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Posted 16 April 2014 - 08:43 PM

so 4.7' is ok?  :rolleyes:






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