Whisker poles

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Mikedefieslife

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My genoa is 7.5oz dacron, and struggles to stay filled when sailing in less than 12knts, this is compounded each time the boat roles.

When the wind is aft of the beam, I think i'd be better off poling out the genoa. I have a carbon fibre pole, but I seem to be missing an end piece. It's at the larger end (which I presume is the mast end).

It's a 48mm section pole at that end, can anyone advise on what end I need and how best to attach it to a carbon fibre pole?

IMG_1337.jpg
 
If using the pole with a pole up / pole down guy, you could just fashion a claw from ply and fit it into the end of the pole. The pole will be in compression anyway and so pushing the claw out against the sheet / clew. Something like and elongated rowlock, maybe with a narrower opening that allows the sheet to slip in but not pop out so easy. Not sure what glue would be best for carbon fibre / ply.
 
I use these kind of spin pole fittings Ronstan RF601. https://www.whitworths.com.au/main_itemdetail.asp?item=80366&search123=80366&intAbsolutePage=1
It does seem like OP has a bit of CF wind surfer mast as a whisker pole. A good idea as I do for a spin pole but that explains the taper. This type of fitting can be bolted onto almost any sized pole by sqeezing spreading or fitting inside the pole. Most other types of fittings require a pretty close internal fit. Further these fittings can be snapped on without opening the beak. I imagine they can be found in UK described as dinghy spin pole fittings. Might however be too smallfor more than 10mm sheets.
I did find that the CF is rather thin and liable to failure where the bolts go through and I have had to build up the area with epoxy and glass where it failed. good luck olewill
 
Old thread warning .....

MIke/OP - Did you find a pole end fitting to match your pole ... which does look like a windsurfer mast?
I was hoping to do something similar and wondered if you had already solved the end fitting issue

Closest I could find to fit the inboard / wide end is this, but seems to be US sourced only - and a bit too pricey just to buy on spec if it didn't fit

PS My thinking for the outboard end for a jib stick would be simply two s/s rings hed on by dyneema lashing - the top one to clip a pole uphaul onto, and the bottom one to have a rope with snap-shackle (or Antal Hook if Santa generous) to hook onto jib sheet, with rope acting both as outhaul and downhaul. This would allow the jib sheet to run free quickly if need to furl or let jib across to manoeuvre
 
Well the end of my carbon fibre tube actually snapped. It wasn't able to take the compression loads of a poled out 7.5oz genoa in 12-15knts.

I'm going to cut off the broken end and try again with a section with slightly more area and see how that goes. I will buy Selden fittings, since there is a dealer here in town.
 
Stuff some sponge down the pole about 75mm really tight. Place the nearest size spinnaker end fitting you can find into the end & wedge with some pieces of plastic to get it central
Stand the pole up against the house by a window ( assuming you do not live in a bungalow) Fill the end around & inside the fitting with resin ( make sure you do not stop the return spring from working the piston) & allow to cure. When done place 2 No. 4mm bolts through the whole thing.File off any rough spots taking care not to raise any carbon strands & then coat the outside end with varnish to seal the end of the pole . You should be able to bolt a couple of hoops through the resin with the 4mm bolts for the uphaul & downhaul & release line etc The bolts will also help secure the end fitting. The resin will resist compression & take up any slop in the fitting
Finally you have to check that the fitting is not so small that you do not get a "shoulder" on the boom which will catch on the mast when held by the ring when at right angles to the boat as it will want to break the end due to high leverage at that point
 
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Mikedefieslife said:
Well the end of my carbon fibre tube actually snapped. It wasn't able to take the compression loads of a poled out 7.5oz genoa in 12-15knts.

I'm going to cut off the broken end and try again with a section with slightly more area and see how that goes. I will buy Selden fittings, since there is a dealer here in town.
Click to expand...

Interesting. Did the pole split at a screw hole or simply break without any existing point of weakness?
What size of boat? And what length of pole?

I would have thought a windsurf mast should be quite strong
 
Force4 do a cheap one. The one that they advertise is 22mm but they also do a larger one which they have to order in.
I used the larger ones to make my wisker pole (from a wind surfer mast). I cut some 4 or 5 inch lengths and reduced their diameter to use as shims to mate the piston ends to the pole.
 
I found ,with a 3000 long FG windsurf wave mast section ,that the £13 selden mast composite piston fitting ( as Force 4) is not man enough to deal with the occasional but extremely high leverage forces that you get when manipulating the sail and pole as the wind shifts etc. Shying away from the extremely expensive metal ends,before proving the arrangement, I tried two of these composite jobs and each snapped in the same place when jammed on the mast hoop.So I currently have a strong cord with a large snap hook and this allows the pole to 'float' around the hoop without jamming.
I used a 100mm softwood insert jammed and coated with resin to mount the original test fittings and that has given a good point for fixing.
Because of these occasional high forces and the fragility of carbon fibre I suggest that you must either use a proprietary end that is solidly resined into place or that you introduce a shouldered insert extension in another material that carries a fitting and so keeps the carbon away from the mast.You might look at a mast extension as a basis for this.I have one that is 45 o/d.
The actual pole works a treat,using the spin. pole hoist attached to the outer end.
 
Yes agreed,and obviously the small composite selden fitting has too small a 'jaw' and is not meant for that kind of duty.
But the benefits of the pole,especially the useful ability to furl the jib easily with it in place mean it's worth upgrading the inboard end.
 
dunedin said:
Interesting. Did the pole split at a screw hole or simply break without any existing point of weakness?
What size of boat? And what length of pole?

I would have thought a windsurf mast should be quite strong
Click to expand...

There were no obvious signs of weekness when I was running it.

My genoa is a medium to heavy material at 7.5oz and is 36m2. The pole would bend a good 20 degrees under compression. I just think the thin end that attached to the genoa was too small. It tapers massively from the rear to the front. The fitting was torn out and the tail end of the fitting is what probably caused the damage in the photo.

As I said I'll just try again with a shorter piece. It is 4.6m long, so I'll cut 20cm off the end.

IMG_2019.jpg
 
Mikedefieslife said:
There were no obvious signs of weekness when I was running it.

My genoa is a medium to heavy material at 7.5oz and is 36m2. The pole would bend a good 20 degrees under compression. I just think the thin end that attached to the genoa was too small. It tapers massively from the rear to the front. The fitting was torn out and the tail end of the fitting is what probably caused the damage in the photo.

As I said I'll just try again with a shorter piece. It is 4.6m long, so I'll cut 20cm off the end.
Click to expand...

Interesting, thanks. Initially I was not thinking of going anywhere near 4.6m, but probably just start with the lower mast section only at 2.6m. This is in fact only about 0.65 of J, but from some geometry and mock ups (using a boat hook) I think this should be plenty to stabilise a narrow blade jib (not intended for trade wind sailing!)
 
Yeah 4.6m is excessive, but the foot of my genoa is huge due to the aft set mast.

At 2.6m you shouldn't have any problems. Mine is actually two pieces that slot together. I imagine that the base piece is close to 2.6m on its own, and it is very solid.
 
Carbon is not the correct material if using a windsurf mast. Carbon masts are very strong in compression & bending. But only when these forces are applied in the correct manner. Where the boom goes they often need a sleeve & at the foot the coupling is a proper fit & applies the force in the designed manner.
If one drops a carbon mast ( As I did once) it can easily shatter. If one were to compress the round end across its circumference so it forms an oval it will quickly distort & then form longitudinal cracks. If the end fitting were to jam on the spinnaker ring, possibly because it was not the correct size, it will apply high leverage to the end & the carbon will split a short length from the tube.

A GRP mast is far stronger in these applications. (Better still a GRP wave mast)Carbon is used in windsurfers for weight & recovery when bending. Same in my dinghy mast. In a gust it bends quickly releasing wind from the sail but recovers fast.That does not mean that it will make a good spinnaker boom if not specifically made for the job
 
To prevent the inserted fitting from gouging its way out through the side of the tube (the rectangular slot in your photo) I would try to reinforce by building a collar around (1) the end of the tube and (2) in line with where the fitting ends when fully inserted. I would build the two collars with epoxy resin reinforced not with carbon but with glass rovings wound around the tube, building up as necessary and tapering to avoid drastic changes in strength (hard spots).
 
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