PDA

View Full Version : rope grommets



didio
02-17-2004, 07:56 PM
Can anyone provide some helpful hints regarding the finer points of making rope grommets? I have Hervey Garrett Smith's Marlinspike Sailor book which gives a good description of the process, but my attempts wind up either twisted up too tight or way too loose. I am also having a hard time getting them to come out to the desired size. Maybe those two problems are related. I'm using 3/8" spun dacron. I starched the rope before unlaying so that it would hold it's shape better. I'm trying to make a grommet about 11" in diameter. Would it help to make something smaller to get the hang of it? Some other questions that come to mind: Do you work with the grommet on a flat table or do you hold it freely in your hands as you wrap the working end around the loop? How do you deal with the working end while you are winding it around the loop--do you pass it through the loop with every turn or do you wrap it around a couple times then pass it through a couple times? The working end seems to want to twist up like a tangled telephone cord as the work progresses--do you let it dangle down and untangle itself every so often? Do you try to put a slight twist into the strand as you are winding it in order to tighten up the yarns? Does it make sense to mark off the length of the circumference of your grommet on the strand before you unlay it?--maybe mark a small dot on the strand a few inches from one end and then another dot a circumference length away to help align things when you form the initial loop? I suppose this is one of those things that's hard to describe--you just get a feel for it.

Todd Bradshaw
02-17-2004, 08:55 PM
Yes, it's pretty much a matter of practice. In order to get multiples the same and to get finished grommets to come out the desired size you can count the little kinks in the line to find the starting position for the very first crossing of the strands. If you start with a fairly firm twist on the strand (but not too much) and fit it around a coffee can, for example, to find the first intersection, then it's probably wise to add a kink or two more to account for the finished rope's thickness and start from there. The finished grommet will likely fit nicely around the can. Sometimes you make your best guess, build one, test it for size and then adjust as needed to get it slightly bigger or smaller. As long as you use similar twisting pressure on a batch and you started with the same number of kinks, they will all be pretty close in size.

The key is always the amount of twist tension. It should be as close as possible to that which the strand had as part of the rope. Too much and the grommet's size gets unpredictable or the whole thing twists like crazy. Too loose and it's mushy and weak. I usually work with the line in my hands, rather than on a flat surface. It gives me a better idea of whether it's twisting or not and there are no foreign influences changing it's shape - what you see is what you get.

If there is anything in the process that seems unclear, get a chunk of manilla to prectice on. Then when you move on to the soft Dacron all you're fighting with is the material itself. I can generate varying amounts of stiffness (from close to original to pretty darned stiff) using filament Dacron which I stain with wood stain, depending upon how much of the stain I rinse out with solvent when coloring the rope. Unfortunately, spun Dacron doesn't take stain very well and it may not work there.

htom
02-17-2004, 09:06 PM
I only make them in manila and do so in hand, starting by holding middle and working both ends around at the same time, left side, right side, left ... until each end has gone around once. I cheat by cutting the line too long, too.

alteran
02-17-2004, 09:28 PM
Todd Bradshaw...

I notice you are in Madison and seeing your posts I know you are familiar with boats. I'm looking for a Holder 14 sailboat. Do you know if they are popular at all on the Madison lakes?

And would you know where I might advertise for one? A UW sailing club or some Madison area sailing clubs? Or somewhere else down there?

Thanks, Al.

Dave Hadfield
02-17-2004, 10:14 PM
I too make them in hand. The stiffer the rope the better, since then you don't really have to do much twisting -- the strand just lays in the groove that magically appears.

I did some in Buff Polyester that were a little more difficult than manilla, because, as Todd says, it didn't hold its lay quite as well and some twisting was required.

Nothing more than practice, I think....

Are you making blocks?

Todd Bradshaw
02-17-2004, 10:27 PM
Al, I don't know whether I've ever seen a Holder 14 here. In any case, I don't believe there are groups of them racing. You can check with "The Sailboat House" which is the largest new and used sailboat dealer in the area, but I don't know what they have at the moment.

ChuckG
02-18-2004, 12:15 AM
one good trick to making grommets is to use another piece of line to model the grommet on, unlaying the line as you replace one strand at a time with the strand you're making the grommet from...
Use a piece of manila for practice, practice, practice smile.gif
cg

[ 02-18-2004, 12:16 AM: Message edited by: ChuckG ]

Otter
02-18-2004, 05:26 AM
As mentioned, it is much harder to do them on poly material than on natural material. I did the try and try again method until I stumbled on a method that Chuck mentions.

There is a good "how to" of this method with pictures in the book "The Complete Rigger’s Apprentice" by Brion Toss. Its much easier to set them in the lay and to calculate the finished size.

Paul Scheuer
02-18-2004, 11:35 AM
That's a lot of grommet. What's it for ? You might have better luck and get a better feel for what's involved by working a little smaller. I have trouble getting large eye splices to lay flat, without any twist.

Manila with lots of character would probably lay back together better.

Working on a flat table would keep things even until you really get the hang of it.

You might also consider a long splice rather than unlaying and relaying a single strand.

didio
02-18-2004, 07:01 PM
Dave & Paul-

I'll be using the grommets mainly for the blocks on the boat I'm building--36' sharpie schooner. I needed a few more larger ones where the finished size wasn't as critical so thought maybe it would be good to practice on those. I posted this question on Brion Toss' Spartalk forum and he recommended the use of Elmer's Kid glue to stiffen the rope before unlaying. That may be the ticket since most of the folks here stated that the job would go easier with stiffer manila rope. I'll get it eventually! Thanks to all for the advice.

Todd Bradshaw
02-18-2004, 08:38 PM
Just get some of these handy little grommet seeds and water them regularly....
http://www.imagestation.com/picture/sraid104/p1581dbb4a5e68166b9ad8f625cc8e50e/f994f7bc.jpg