How to taper spin sheets

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How to taper spin sheets

Postby slowpoke » Fri Mar 16, 2012 6:08 am

I ran across this on the web tonight, thought I might post it here.


http://www.sonar.org/site/files/Library ... Sheets.pdf
Rocky Shelton
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Re: How to taper spin sheets

Postby Chad » Fri Mar 16, 2012 4:34 pm

So how big a cover can you stuff into a 7/32" spectra core?
-guess I'll find out tonight.

Found that camera yet, Rocky???
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Re: How to taper spin sheets

Postby Kevin » Fri Mar 16, 2012 5:00 pm

Generally you can use 1 size up cover to core. So a 6mm (1/4") line (sta-set for example) can hold a 5mm (7/32" or 3/16" depending on the brand) 12 strand core. Sta-set isn't the most exciting cover in the world, but it's one of the best and cheapest ways to get small line cover for a spectra line that I've found.

Rigging Only usually has cheaper prices then the big online guys but they don't have the gucchi stuff, mostly new england is what they carry.

Kevin.
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Re: How to taper spin sheets

Postby Chad » Fri Mar 16, 2012 5:29 pm

Meant to write 7/64" for the core...

I have some 1/4" Staset to rob some cover from, but I doubt it'll fit. Might be a case of tapering the cover and just whipping the end to the core, while trying not to create a stiff spot. Or tapering from 1/4" to 1/8" then to the 7/64", which sounds like a bunch of work. Good thing there's crap tv on tonight...
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Re: How to taper spin sheets

Postby Kevin » Fri Mar 16, 2012 5:53 pm

They make staset in a 3/16" size which works for 3mm spectra ok (my outhaul tail has that cover). But a 7/64" spin sheet seems really light ;-) maybe your are doing something else with that evil thin line. Another option is to get a chunck of 4.8mm spyder line which has a non-braided spectra core and use that. Did you know you can braid the core of the spyder line at the end if you really wanted to. Maybe a brummel splice for the tail. The trick with that is there will be a wide spot behind where the cover comes out. My halyards have this issue because they are vectran core and I transition to spectra, pull the cover over that and then bury the cover into the spectra.

Oh, and the worlds cheapest splicing tool is probably sitting in your house and you don't even know it. A small diameter wire and a washer is all you need. I personally use a length of cat-5 networking cable. Specifically I use one of the 8 wires (with insulation in place) from inside the outer covering. It's easy to pull the cable apart to get 1 wire and you have 7 handy replacements. I find a 48" length bent in halve works well. I usually get about 50 + splices before the wire breaks. For small diameter line (less then 3mm) I use 26gauge wire and it works great.

Note that you should always make your tapers nice and long with spectra. I think 72 times the core diameter is the right and safe number for the bury length and the last two thirds of that should be tapered. Spectra hates an abrupt end to the bury and will fail at that spot. In the case of this buried cover, when you are putting the cover into the core, your issue is not getting the core in, but tapering the core so the spectra which is now on the outside doesn't fail. And I've been known to taper the cover before the bury to get the cover inside :-).

I find 12 strand so easy to work with that I've sworn off regular double braid line. It's just not worth the time it takes to splice the darn stuff. And spectra lets you smaller and lighter anyway.

Kevin.
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Re: How to taper spin sheets

Postby Chad » Fri Mar 16, 2012 6:59 pm

Yes, 7/64" stuff is just for some purchase under deck, not spin sheets. I'd like to end up at 1/4" so I don't murder my hands and so there's enough there to get a good pull on, and the cleat can hold it better.

I use bits of wire coat hanger for my splicing tools. A six inch "hairpin" with the fold clamped into a tight 180 for lines over 1/8", and just a straight 6" piece with the ends filed round for small stuff. And little wraps of thin masking tape to attach the line to the wire. I bought a cheapo ceramic knife from ebay or amazon, and it makes cutting the spectra much easier.

For spectra, 72 diameters of bury is the standard (=9" for 1/8" line), and I taper the last 2" evenly all the way down to a single strand. You shouldn't feel the step up when you run your hand over the splice. Brummel first, or stitching after for no-load security (against flogging).

I've decided to avoid vectran, since the spectras seem to match its performance now but without the uv issues.

Some spectra's work differently- Amsteel opens up nicely when you scrunch it, but some others don't. NER's sk90 opens nicely, but Cortland's Plasma is lots stiffer for two extra data points.
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Re: How to taper spin sheets

Postby Kevin » Fri Mar 16, 2012 9:03 pm

I fixed my post regarding the bury length to ensure we didn't have anyone use the wrong number in the future.

I would not pay for vectran again. I purchased 1/4" v100 for both jib and main halyards. In fact, I probably wouldn't pay for 1/4" line again, one size smaller and probably start with 12 stand sk-75 and then just add cover where I want it. Since my boat's only in the sun when I'm sailing, my setup will probably last a life time so I'll not have to think about this again.

I've used both amsteel "blue" which doesn't have to be blue and endura 12 (now called sts-12-75). The amsteel is flatish when new and softens up quickly when you work with it. If you get colored amsteel it will come off on your hands and you can see where it's not coated. I think the apply they coating post braiding personally. The sts-12-75 is round and stiffer out of the gate, but not hard to work with at all because the center is hallow and the tools usually zip through. Each strand seems to be coated prior to braiding to me.

I also had a ceramic knife. Don't drop it because it will break very easily. After mine broke I pulled out the stones and sharpened my pocket knife properly (Japanese water stones and a holder = mirror finish) . It cuts just as well as the ceramic knife did when sharp. A strop is a good way to keep that edge on a metal knife, not sure that would be effective on a ceramic knife, mine broke before I could try that. It's time to sharpen it up again, but there are other priorities on my list.

Kevin.

p.s. APS whipping trick... pull the cover back and cut the core short of the end (1 diameter from the end will do). Use a hot knife to cut and melt the cover and clamp it closed with a pair of old pliers (a lighter can also be used in a pinch). Add a proper whipping and you are good to go. If you don't do this the spectra core which doesn't really melt on the hot knife will eventually loosen from the cover. And who would disgrace their nice boat with a frayed knot? ;-)
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Re: How to taper spin sheets

Postby Chad » Sat Mar 17, 2012 3:59 am

Pliers? I've always shaped my butane backsplices with wet fingers...

I avoid burning the ends now (not because I kept burning my fingers!), instead I just whip near the end and cut the line cleanly. Sure, it gets a little fuzzy on the end, but there's no harm in that unless you need to feed fat lines through small blocks. On other people's boats, I always find myself picking at the little hard bits at the end of the line on the way out/back from racing, like a scab you can't resist. Personal problem, I'm sure.
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