SailNet Community banner

1 - 13 of 13 Posts

·
Registered
Joined
·
5,067 Posts
If there is a local 'metal worker' who specialized in 'boilers', boiler repair or heat transfer equipment / heat exchanger building/repair ... this person will undoubtedly have a tube bending devices (rollers, jigs, etc.) and will 'most times' be able to correctly straighten a foil.
Unfortunately aluminum doest take kindly to much repeated bending ... so there is always a risk of fracture when re-straightening (or bending) aluminum.
 

·
Registered
Joined
·
2,825 Posts
are you sure it is bent or just laying there flexed to a curve. if it is bent it can be straightened but takes a little know how. some can be over flexed the opposite direction and will return to straight. I have done a few over the years but it is hard to tell someone how to do it. try it what do you have to lose.
 

·
Registered
Joined
·
16 Posts
To my untrained eye, that looks to me like a flexible furler, something akin to a CDI or hood seaflex. If so, an excerpt from the cdi manual has the answer: the furler can be "straightened by bending the luff in the opposite sense until it comes straight. Another option is to put the luff in a pipe or tube outside in the sun for one to two weeks to straighten it."
 

·
Registered
Joined
·
2,343 Posts
In my humble opinion, don't do anything. Tension on the backstay and you won't notice it.
Agreed

Every time my rig has been down the furler has looked like that. Once back up and properly tensioned it looks and works just fine.

Barry
 

·
Registered
Joined
·
153 Posts
The make of the furler would be helpful. If that is a CDI flexfurl then it will most likely depend on the age of the furler as to whether it will straighten up or not since they become brittle over time. You could try placing it in a tube and allowing it to warm up in the sun as suggested on their site. I do not recommend trying to bend it in the opposite direction (personal experience here) as it will most likely crack. A replacement CDI luff is about $200.00 and readily available so not all is lost.
 

·
Registered
Joined
·
16 Posts
Still a flexible furler. I'll second the comments about tensioning the rig. My own boat has a Hood SeaFlex, and the foil extrusion tends to bend a little when the rig is down for trailering. Just some of the "memory" curvature from how it was shipped that has never fully corrected itself. But if you notice curvature while its up and tensioned, laying it out in the sun in a tube should do the trick. Worked for me for a more severe bend that occurred due to how the PO stored the furler. Had found the info from CDI a few years ago, hence the reason I posted it for your sake earlier.
 

·
Senior Member
Joined
·
19,489 Posts
If it's not visibly kinked, agree... install and tension rigging you will likely be fine.
 

·
Sailnet Vendor
Joined
·
170 Posts
Anybody know how to straighten a furling foil for the jib? It's not bent too bad, you can see it in the pic.
I'm pretty sure it's a Schaefer SnapFurl. I'm not sure whether it's a CF-500 or CF-700 from the picture.

I am an authorized Schaefer and CDI distributor for many years, so I have extensive experience with the extrusions on both of these plastic furler. I have scrap pieces of extrusion lying around, and I have done 'destructive testing' on the plastic extrusions. :eek: I know alot more than most people about how to wreck a plastic extrusion for a furler . :D

The Schaefer Snapful extrusion is made of two half cylinders the length of the forestay that snap together with the wire in the center. When assembled, the two halves can slide up and down relative to each other even after they are snapped together. The two-half construction and slippage between the two halves contributes to the preventing permanent deflections when the extrusion is flexed.

When you bend the assembled foil, the two halves slide so that the one on the inside of the curve has a smaller diameter curvature than the half piece on the outside of the curve. This ability for one half to slide vs the other reduces axial compression and tension on the inside and outside of the curved extrusion, and reduces the potential for permanent plastic deformation.,

(It's vaguely analogous to the opposite effect of laminating strips of wood together to create a curved tiller. If the laminated strips of wood were free to slide, the tiller would straighen itself out. )

In this situation, you will find that you can flex the extrusion gently back and forth, allowing the two halve to re-align themselves and it'll be fine.

However, for both brands, the plastic extrusions can and do deform when left permanently bent, especially in a hot environment. In this case it is difficult, but not impossible to straighten them somewhat..

I have seen both the Schaefer and the CDI plastic extrusions become almost permanently deformed in one of two common ways: `1) the furler is left un evenly supported unevenly and left in the heat or 2) the extrusions, which is coiled in an approx 40" coil is left that way for extended periods of time.

I have successfully straightened both CDI and Schaefer extrusion. Not perfectly straight, but significantly straighter. I have a 30' long piece of black 2" diameter pvc pipe for straightening plastic extrusions that were left coiled for extended periods of time after they were delivered. I put the two halves of the extrusion in the pipe, stuffed rags in the end, and put it in the California summer sun for about 10 days. I checked on it and turned it every couple of days. It straighened out considerably.

It is a fact of life that both the Schaefer and the CDI plastic extrusions can take a permanent set if left kinked for a long time, especially in hot weather. Sometimes they are too deformed to be straightned, In this case, tightening the backstay does NOT remove the bend in the luff.

If the luff has been left poorly supported for a long time, it may be necessary to replace the extrusion. A new Schaefer SnapFurl extrusion CF-500 is MSRP of $383, the big brother CF-700 replacement extrusion is MSRP of $396. Street price is, thank goodness, lower. However, shipping is expensive because they are bulky and oversized. shipping runs to about $55 anywhere in the USA for the CF-500 and up to $120+ for the CF-700 extrusion.

In my experience, it is possible to store a Snapfurl bent in half inside the cabin, with a 6' diameter bend without permanently harming the extrusion.

In my experience, the two piece Schaefer SnapFurl extrusion is less vulnerable to permanent distortionthan the one piece CDI plastic extrusions. Often, you can reduce the apparent bends in a Schafer SnapFurl by picking it up and gently curving it back and forth.

The extrusion of the CDI is one piece, and is not always as forgiving. The shape of the extusion is a flat ribbon. You can bend curve it gently in along the flat side without permanent deformation, but not along the narrow side.

Finally, preventing deformation is the best "cure" of all. When you strap your furler to the mast for transport, put a bungee every 2 feet to prevent the furled sail on the extrusion from sagging in between the bungees. Avoid any sharp curves. Take care near the spreaders to keep it as straight as possible. Bungee a support onto the mast at the base, so the furler is supported by something rigid for its full length so it isn't bouncing around while you drive. If you don't support the bottom end of the furler & foil, the plastic foil will snap right near the base of the mast from fatique due to bending and bouncing as you drive (Been there, done that)

Feel free to ask if you have any more questions or feel free to PM me.

I hope this post reads okay. It's long and I'm too tired to proof read it carefully. It's dinner time.... Folks, feel free to jump in and correct any obvious typos and mis-cut-n-pastings.
 

·
Registered
Joined
·
1,073 Posts
Like others have said, set it in the sun for a few days. Plastic has memory and wants to return to its original state. Maybe encourage it a little by putting heavy objects in its path and forcing it to straighten. Then put it back on and worry not! IN the future, pull it tight so it overhangs the end of the mast, put a length of 2X4 between the two and bungee like crazy.
 

·
Registered
Joined
·
412 Posts
To my untrained eye, that looks to me like a flexible furler, something akin to a CDI or hood seaflex. If so, an excerpt from the cdi manual has the answer: the furler can be "straightened by bending the luff in the opposite sense until it comes straight. Another option is to put the luff in a pipe or tube outside in the sun for one to two weeks to straighten it."
I think those instructions are for the plastic furler, which is virtually unbreakable. I wouldn't try that with an aluminum extrusion.
 
1 - 13 of 13 Posts
Top