Thanks for the reply

What you posted seems to mirror what i have read about that rig over the years. Good to hear real world facts.?

My thinking, with Bernd help, is to keep the current good traits of thar rig, and improve the few problems that need fixed?

One, as you said, is sail managment.?

I wonder, if using a carbon top gaff would help with the adjustments, due to less weight??

I havent ruled out the high roach main option.?

On Sat, Dec 30, 2023, 5:41?PM R Flegg <richard@...> wrote:

Hi, I had a Wharram Wingsail on my Hinemoa - it is an approved option for which you can buy the plans. I used a round aluminium mast made by Z-Spars and sails by Jeckells. I used Dyneema shrouds and stainless forestay ?with roller reefing. If you haven’t sailed a boat with the WW sail you perhaps should before committing. The sail is both powerful and forgiving of poor sail setting, particularly off wind, and it is possible to spill a lot of wind high up by letting the gaff swing out if you need to loose drive in a hurry. The boom less design is also a good safety feature on an open deck boat. I know a lot of people swear by them, but I would not have another out of choice because it is not particularly close winded and getting it up and down the mast, particularly in strong winds, can be a struggle. The gaff angle is critical and not always easy to manage when everything is flapping about and you need to get the sail down in a hurry. Also my sail was fairly stiff and reluctant to fold neatly as it came down the mast with a propensity to trap the external halyards if the folds were not neat. My problems may have been uniquely bad, but you will find other articles about the raising/lowering issues so I am not alone. In summary: a good powerful sail particularly for off wind sailing, but raising/lowering may not be easy, especially ?in strong winds.

A personal view, others will no doubt disagree.

On 29 Dec 2023, at 15:38, Bill Mansfield <billman3968@...> wrote:

?

Thxs, i think for smaller mast, this works. For a long, wider mast, not so sure with the compression, you can get it off. Even with the proper epoxy finish, release agent, peel ply ect on thr manderl. Smaller yes, i have done it.

Thats why im just going to buy am alum mast, and use the wharram soft wing sail on the boat.?

With the pvc part inside, the carbon needed, and the epoxy, i doubt i can make a lighter weight mast then a str8?

Alum pole with light rigging

On Thu, Dec 28, 2023, 6:43?PM David Mancebo via <mancebodesigns=[email protected]> wrote:

Bernd suggests leaving the mandrel inside the finished mast. Here is another option I have used. After applying mold release to the mandrel, laminate a couple very thin layers over the mandrel and cover with peel ply. When the resin is at the "green stage", i.e. semi-hard, slit it with a razor knife. After cure, open the part where it was slit so it can slip off the end of the mandrel. Remove the peel ply and add a layer or two of glass tape over the slit. You now have a light weight mandrel to add carbon and resin for the full mast tube construction.

I originally used this method on a borrowed aluminum mast. I removed all the fittings, sealed the bolt rope slot and fastener holes with packing tape. I used 2 layers of 110 gsm fiberglass cloth in epoxy resin to make my light weight mandrel. The mast was only 6 m long and I used a single interum support. A larger mast would probably need more glass or more interum support. The packing tape was hard to get off the Aluminum mast later. If the mast shape allows, I would just wrap release ply over it instead.

I attached a picture of an off-cut of the carbon mast I built using this method.

Hi, I had a Wharram Wingsail on my Hinemoa - it is an approved option for which you can buy the plans. I used a round aluminium mast made by Z-Spars and sails by Jeckells. I used Dyneema shrouds and stainless forestay ?with roller reefing. If you haven’t sailed a boat with the WW sail you perhaps should before committing. The sail is both powerful and forgiving of poor sail setting, particularly off wind, and it is possible to spill a lot of wind high up by letting the gaff swing out if you need to loose drive in a hurry. The boom less design is also a good safety feature on an open deck boat. I know a lot of people swear by them, but I would not have another out of choice because it is not particularly close winded and getting it up and down the mast, particularly in strong winds, can be a struggle. The gaff angle is critical and not always easy to manage when everything is flapping about and you need to get the sail down in a hurry. Also my sail was fairly stiff and reluctant to fold neatly as it came down the mast with a propensity to trap the external halyards if the folds were not neat. My problems may have been uniquely bad, but you will find other articles about the raising/lowering issues so I am not alone. In summary: a good powerful sail particularly for off wind sailing, but raising/lowering may not be easy, especially ?in strong winds.

A personal view, others will no doubt disagree.

On 29 Dec 2023, at 15:38, Bill Mansfield <billman3968@...> wrote:

?

Thxs, i think for smaller mast, this works. For a long, wider mast, not so sure with the compression, you can get it off. Even with the proper epoxy finish, release agent, peel ply ect on thr manderl. Smaller yes, i have done it.

Thats why im just going to buy am alum mast, and use the wharram soft wing sail on the boat.?

With the pvc part inside, the carbon needed, and the epoxy, i doubt i can make a lighter weight mast then a str8?

Alum pole with light rigging

On Thu, Dec 28, 2023, 6:43?PM David Mancebo via <mancebodesigns=[email protected]> wrote:

Bernd suggests leaving the mandrel inside the finished mast. Here is another option I have used. After applying mold release to the mandrel, laminate a couple very thin layers over the mandrel and cover with peel ply. When the resin is at the "green stage", i.e. semi-hard, slit it with a razor knife. After cure, open the part where it was slit so it can slip off the end of the mandrel. Remove the peel ply and add a layer or two of glass tape over the slit. You now have a light weight mandrel to add carbon and resin for the full mast tube construction.

I originally used this method on a borrowed aluminum mast. I removed all the fittings, sealed the bolt rope slot and fastener holes with packing tape. I used 2 layers of 110 gsm fiberglass cloth in epoxy resin to make my light weight mandrel. The mast was only 6 m long and I used a single interum support. A larger mast would probably need more glass or more interum support. The packing tape was hard to get off the Aluminum mast later. If the mast shape allows, I would just wrap release ply over it instead.

I attached a picture of an off-cut of the carbon mast I built using this method.

Bernd suggests leaving the mandrel inside the finished mast. Here is another option I have used. After applying mold release to the mandrel, laminate a couple very thin layers over the mandrel and cover with peel ply. When the resin is at the "green stage", i.e. semi-hard, slit it with a razor knife. After cure, open the part where it was slit so it can slip off the end of the mandrel. Remove the peel ply and add a layer or two of glass tape over the slit. You now have a light weight mandrel to add carbon and resin for the full mast tube construction.

I originally used this method on a borrowed aluminum mast. I removed all the fittings, sealed the bolt rope slot and fastener holes with packing tape. I used 2 layers of 110 gsm fiberglass cloth in epoxy resin to make my light weight mandrel. The mast was only 6 m long and I used a single interum support. A larger mast would probably need more glass or more interum support. The packing tape was hard to get off the Aluminum mast later. If the mast shape allows, I would just wrap release ply over it instead.

I attached a picture of an off-cut of the carbon mast I built using this method.

Hi David and all

Building masts, in general, is like building another hull.?
Some remarks and tips.
I propose using PVC gutter tubes as mandrel.? Then the can stay in the mast.
As you have experienced, it is almost impossible to remove these. Logically, epoxy shrinks by about 2 % when curing.
You can not work on a table to build masts. We used steel wires between walls (or as shown in the sketch)

We spliced steel cables between two walls using tensioners. The PVC pipe can then rotate and make the work easier. The sketch is from an old boat building magazine. It shows the idea of how to
build a glass fiber mast or carbon mast. My DUO 800 plans also show how to build a filament winding device. This makes building masts a little easier. In any case, things are much better when there are two of you.

Bernd

Can not be done in sections

The mast layup is a well-calculated construct from diagonal layers, UD layers of carbon, and UD glass fibers.
Stress analysis indicates that the mast has to be strong in tension (for this carbon) and compression (for this diagonal glass and UD glass fibers).
Were it so simple, we would have more freestanding masts. Don't tamper with layups I sho9w, for instance, for the DUO 800 pasts.

Bernd

Thanks?

Never thought about leaving the pvc inside the mast. I ask (i dont know)?

Is the weight? still less then a alum. Mast while using a combo of pvc and carbon??

While thinking on this a bit more, you could do the pvc with carbon in smaller sections, and use inside sleeves to connect the sections before doing a final top sleeve layer over the whole sha'bang (mast)?

This allows us to use thinner(lighter) pvc material. If this pvc is used in smaller sections, bending wont be a problem.?

Good stuff thanks again?

On Sun, Dec 24, 2023, 10:43?AM Bernd Kohler <ikarus342000@...> wrote:

Hi David and all

Building masts, in general, is like building another hull.?
Some remarks and tips.
I propose using PVC gutter tubes as mandrel.? Then the can stay in the mast.
As you have experienced, it is almost impossible to remove these. Logically, epoxy shrinks by about 2 % when curing.
You can not work on a table to build masts. We used steel wires between walls (or as shown in the sketch)

We spliced steel cables between two walls using tensioners. The PVC pipe can then rotate and make the work easier. The sketch is from an old boat building magazine. It shows the idea of how to
build a glass fiber mast or carbon mast. My DUO 800 plans also show how to build a filament winding device. This makes building masts a little easier. In any case, things are much better when there are two of you.

Bernd

Hi David and all

Building masts, in general, is like building another hull.?
Some remarks and tips.
I propose using PVC gutter tubes as mandrel.? Then the can stay in the mast.
As you have experienced, it is almost impossible to remove these. Logically, epoxy shrinks by about 2 % when curing.
You can not work on a table to build masts. We used steel wires between walls (or as shown in the sketch)

We spliced steel cables between two walls using tensioners. The PVC pipe can then rotate and make the work easier. The sketch is from an old boat building magazine. It shows the idea of how to
build a glass fiber mast or carbon mast. My DUO 800 plans also show how to build a filament winding device. This makes building masts a little easier. In any case, things are much better when there are two of you.

Bernd

You got here something wrong. Because I am sure I did not write this.
Here again is some general wood data.

?

See table—some wood data for plywood for boat building.

?

Matterial? ? ?Weight? ? Bending moment Elasticity modulus

?

Meranti? ? ? ?710 kg/m3 32 N/mm2? ? ? ? 7000 N/mm2

Mahogany? ? ? 650 kg/m3 80 N/mm2? ? ? ? 8300 N/mm2

Okoume? ? ? ? 430 kg/m3 84 N/mm2? ? ? ? 8600 N/mm2

?

The table clearly shows why I prefer Okoume, Gaboon, and Bruinzel plywood (made from Gaboon).

The general impregnation of Epoxy adds between 10 and 15 % of the strength for an impact of about 30 %.

Bernd

?

?

I have made carbon tube battens for a junk sail, 60mm diameter and 6m in length, using carbon sleeves from Soller Composites. It is not an easy process. You need some form of mandrel for the sleeve to go over, you need a mechanism to elongate the sleeves along the mandrel, and then it is not easy to consistently wet out the carbon with epoxy to get a proper wet out. Then the whole thing needs to be kept straight while the epoxy is curing, and then you need to be able to remove the finished carbon tube from the mandrel. We had to tie one end of the carbon tube to a stout fence post, and then use a 4x4 vehicle to pull the tube off the mandrel.

?

There are many obstacles in front of the amateur builder successfully making carbon tube. Based on my experience I would not attempt it for making a mast. You would be much better off to purchase commercially manufactured carbon tube because otherwise you will likely end up with a very expensive mistake.

?

David

?

I just finished a special version of the DUO 480 JIGSAW for Harald. You know he built (and some others too) a beautiful Cataproa. See video clip

?

Parallel rig or sloop was the critical point. In the end, it will be the parallel* rig. Because I found at last a manufacturer.?

?

Brian in New Zealand built the first DUO 480 Jigsaw with the parallel* rig see video.

Because carbon masts are a lot cheaper there.

Now, this company in the Netherlands makes just the good carbon tubes with an acceptable price of Euro 553.32).
I will place the company address in the file folder of our forum.??

?

* many use biplane rig for a parallel rig. But does the rig have anything to do with a biplane?