Author Topic: Is there a calculation which gives the amount of cordneeded for a turks head?  (Read 8974 times)

Mrs Glenys Chew

  • Administrator
  • Exp. Member
  • *****
  • Posts: 200
Dear All

I've been doing some work with turks head mats, in a variety of thicknesses of haberdashery material (ranging from 6mm wide ribbon, which I put a slight twist on, through embroidery silks, to anorak cord, leftover cord from curtain pulls, and so on).

Has anyone ever done a calculation which says that for "x bights/ x leads / x no of passes in x mm wide cord" you will need x metres of cord?

I'm not possessed of very large supply reels of cord, but need to buy them as I go, and I'd like to do some stuff like making belts, hairbands, bracelets, and so forth in various thicknesses of cord.

Or am I going to be the first to ask the question, and in 10 years I shall have enough information accumulated to be able to share the results with you all ;)

Regards

Mrs G Chew

Regards
Mrs Glenys Chew
1 Corinthians 15:10

Andre van der Salm

  • Exp. Member
  • ****
  • Posts: 132
  • I am knot crazy
    • Knots and Knot tying
hello again,

I don't know if you are a member of the Yahoo knot tyers group as well (free membership btw), if so you can go to the file section of the group and doenload an excelsheet which contains a cord length calculator especially for TH knots.

groups.yahoo.com/knottyers

success

André

KnotNow!

  • Sr. Member
  • *****
  • Posts: 368
  • IGKT-PAB PAST PRESIDENT
How about a contact for the comupter illiterate?.  How about a membership to IGKT or IGKT-PAB where templates and such are available for the cost of a stamp.  Not everyone has internet access or at a log on rate that will download.  Yes, it is the cost of the real membership in KGKT or KHWW.  You see KHWW looks to be free but if IGKT and IGKT-PAB were not here then there would be no KHWW.  Just a thought.
  I seem to have post of thread and then could not cancel my post.  Sorry about that.  Still will stay with stupid post.. but it has nothing to do with the original question.   I am sorry to not be able to qusash a post of mine.
« Last Edit: October 05, 2006, 05:28:40 AM by KnotNow! »
ROY S. CHAPMAN, IGKT-PAB BOARD.

Knot Head

  • Knot Head
  • Exp. Member
  • ****
  • Posts: 194
  • A knot is not just a knot...
Here's what yer lookin for.

http://www.knotworkn.com/CordageCalchtml.html

This calculator is a free demo. The cost is very inexpesive at the cost of around 15.00 US currency.
Regards,
Brian Kidd

Andre van der Salm

  • Exp. Member
  • ****
  • Posts: 132
  • I am knot crazy
    • Knots and Knot tying
hello again,

the calculator Bud is referring to is completely based on the spreadsheet I mentioned in my earlier post. I did the initial conversion from the excel sheet to the standalone version and Douglas Varney did the rest of the programming. I mentioned the excel sheet in the first place because it's small, free and readily available. But indeed Bud is right..the calculator as it has evolved into the calculator it know is, gives some extra's in the sense of single and multistrand TH knots and a convertor for metric to inch etc etc.

sucess with your TH knots

André

Mrs Glenys Chew

  • Administrator
  • Exp. Member
  • *****
  • Posts: 200
Thank you for the replies so far, I am hoping to get enough time on the computer soon to be able to look at those links properly.

Regards

Glenys Chew
Mrs Glenys Chew
1 Corinthians 15:10

KnotNow!

  • Sr. Member
  • *****
  • Posts: 368
  • IGKT-PAB PAST PRESIDENT
Hi Knothead,
  Free and then to quote a cost?  Your tongue in cheek must look like a chipmunk stealing a golf ball.  Of course we would all like some funds posted to KHWW to keep the site up and running.  But lets stress that the calculator is on line for free!
ROY S. CHAPMAN, IGKT-PAB BOARD.

KnotNow!

  • Sr. Member
  • *****
  • Posts: 368
  • IGKT-PAB PAST PRESIDENT
To G. Chew,  Being a bit slow to embrace the computer here is what I do.  I guess.  I spool off some line and cut nothing.  Then I make the knot and double ply or tripple or quad ply it and if I need more I spool it off and work it through or if I have excessive I work all slack back toward the spool.  I like to work knots so I don't expect a perfect result at the first go.  This results is very tight knots and no waste of cord (perhaps of time.. but).  I also make measurements at the start and the end so my "Knot Knotes" book will let me cut the next cord if I need to.  A bit of thread stitched through the working line makes a marker as needed with no indlible marker on the work.
ROY S. CHAPMAN, IGKT-PAB BOARD.

Mrs Glenys Chew

  • Administrator
  • Exp. Member
  • *****
  • Posts: 200
Thank you, Roy, that is generally what I've been doing so far.  But since I can't always guarantee getting the same cord every time, I just hoped there was some way of being able to work out what I might need in advance.  It saves me from falling short if I under-estimate, and having fiddly lengths left over.

I did work out that 2mm round elasticated cord would give three passes of a simple TH round my daughter's wrist in just 1.1metres.  So now (once I've figured out a neat way of securing it) we can try making TH friendship bracelets which are easily removed (unlike the sort she has previously worn, which don't come off very easily).  No symbolism, I hasten to add, in elasticated, removable friendship bracelets.  Just the practicality of washing your wrists easily, keeping the bracelets looking nice and clean, etc  ;)

Regards
Glenys Chew
Mrs Glenys Chew
1 Corinthians 15:10

KnotNow!

  • Sr. Member
  • *****
  • Posts: 368
  • IGKT-PAB PAST PRESIDENT
Hi Mrs_G_Chew,
  Well, perhaps I miss stated.. the reason I work off the coil is to avoid the leftover ends... I must have posted silly.  I tie the knot and work all the slack back to the coil.  I do this in THK's, Mats mostly.  As to finishing friend ship bracelets; In some cord I just stitch the ends together.  Sometimes I use (I did not say this in public) glue.  In some cord I make real seizings with the best line for the task, sail twine etc.  If your cord is elastic... I think glue will not work very well so suggest some thread and needle work.  I make Spanish Ring Knot bracelets.  These are a modified THK, taught to me by Bob Solon (knot is in ABOK... but not under that name).  These expand a THK into an over two under two herringbone pattern.  The way it works is now there is more slack in the knot so it can be pulled out to fit over the hand and then collapsed on the wrist to a snug fit.  Looks as if it would never come off.  Fits like a tennis players sweat band. But pulled to full circumference... slides off the hand.  Just a thought.
ROY S. CHAPMAN, IGKT-PAB BOARD.

Knot Head

  • Knot Head
  • Exp. Member
  • ****
  • Posts: 194
  • A knot is not just a knot...
She asked and I gave her a link with the correct information. That's it. ???
« Last Edit: October 07, 2006, 02:54:16 PM by Knot Head »
Regards,
Brian Kidd

Mrs Glenys Chew

  • Administrator
  • Exp. Member
  • *****
  • Posts: 200
Good day, gentlemen.  Thank you both for the replies and information you've given me  :)  It's led me to some interesting thinking exercises in maths.  Whether I have the ability to follow through on any of it, I don't know, but I may at some time have the leisure to find out.

I loved the heading design for your sight, Knot Head.  That lovely picture nearly distracted me away from the purpose of my visit!  I haven't downloaded the calculator yet.  I'm trying to decide if it's better if I wait until I get some birthday money, and then buy it properly.  I wouldn't be able to use it more than a couple of times in 30 days, but it is the sort of thing I'd like to keep and use at long intervals.  Are you a mathematician, out of interest?  (I'm not, but I like to expand my knowledge in lots of areas).

Roy, the leftover ends I meant were those after completing full passes.  My first ever TH wsa on a roughly 1m cord, wrapped round a toilet roll inner tube, and I just went with it until I ran out of cord.  Some of it had three passes, and some had only two.  The elastic bracelet I did for Rosanna surprised me.  The strength of the tension (3 passes, 7 bights - have I remembered the right name for the up and down bit; probably not, I must study the terms properly as I go!) needed to stretch the elastic is considerably more than I thought it would be.  It's as if the elastic sort of 'lost' elasticity whenever I made a pass.  I can't remember whose website it was I got the original notes from that I'm using.  Someone who was demonstrating the Woodbadge Woggle.  I lost the link when our computer crashed a couple of months ago.

Got to go now, but thank you again,

Regards
Glenys Chew
Mrs Glenys Chew
1 Corinthians 15:10

Knot Head

  • Knot Head
  • Exp. Member
  • ****
  • Posts: 194
  • A knot is not just a knot...
That calculator is not my invention. That is totally Doug Vaney and Andre van der Salm. They put a lot of hard work into that calculator. I pointed you to Dougs website. He has a free demo to download at his website. If ya download give it try out.
Regards,
Brian Kidd

Loren

  • Full Member
  • ***
  • Posts: 32
    • Golden Knots
When I do rough calculations for the length of materials in a TH (and they are always rough, in my experience, since every occasion gives me slightly different results in real life), I generally resort to the Pythagoras theorem, since the line segment from two connected loops on opposite sides of the band can be regarded as the hypotenuse of a right triangle, and the width of the band is one of the sides.  The other side has to be calculated as follows:  the desired circumference of the knot, divided by twice the number of loops around the edge,, times the number of leads.  This results in a segment of the circumference, i.e. 5/22nds of the circumference of a 5x11 is the distance around the circumference from a loop to a point opposite where it reaches the other side of the knot.

If you know how wide the knot will be, and how long the path is going to be, you can find the hypotenuse, multiply by the number of bights, then double that, to find a reasonable guess as to how much material will be required.

I've got a page or so of discussion of this on my website, where I also mention the possibility, and the undesirability, of considering the path as a messy sine curve and integrating over its length using calculus.  Pythagoras is far easier, and no less useful.

In any case, the closer you figure it, the more important it is to leave yourself some room for error.   It's far more frustrating to start over than it is to scrap a short section of material that isn't needed for the complete knot.  5% is good, 10% might be excessive.

Loren