November 3, 2015

Tatted Relations

There are questions that arise when tatters have a pattern that calls for a specific thread size, "What if I use another thread size?", "What is the equivalence of thread size X?", "If I use another thread size should I add or remove DS to get the same dimensions of the work?", ¨How many?"

Is there a direct relation between thread sizes and the tatted work?

Well, after many, many, many tries I can definitively say there is nothing definitive. Depends on several variables, the thread brand, the lot of the thread (not only for the dying process), the tension that varies every time the tatter tat, how tight the stitches are,  the weather, if it's dry or wet, etc.

Think that you want to tat baby booties, but the pattern ask for thread size 20 and you use/like/have size 10, or any other. We know that size 10 is thicker than size 20, then the booties would be bigger and thicker than expected. The finished project needs to have a specific size, it's not a doily at all. What can we do?

A) Direct solution: Go shopping for size 20, perfect excuse to buy new and wonderful threads, don't forget to buy the one you're needing. Or forget it and go back shopping...

B) Try and fail solution: Tat samples to compare untill you have what you're looking for.

C) Have a Tatted Thread Sizes Relation Table. My solution. Not perfect, but useful.

Now comes the maths part. Wait!!!, don't close the page yet! I'm not going to talk of mathematical topics in quantum theory at all, although I would love to...


Are you still reading? Good. You're brave. Let's talk about the Table of Tatted Threads Relation.

We can define a relation between the tatted threads with a tolerance error, generally 3% to 5%, for adapting a pattern designed for a thread size to another size.

Going back to our example, the booties designed for size 20 that we will tat in size 10.

I go to my table and find row for Size 20 and the column for 10 and get 146%. What does it means? Means that the finished tatted work will be 100% the original size and increased by 46% (if the percentage is higher than 100 so the tatted work will be. If the percentage is smaller than 100, so will be the tatted work. If the percentage is 100, doesn't change anything).

Now I know that I have to decrease the number of DS by 46% for each shape (ring, chains, bare thread), and picots used for joining, to get my booties in the correct size for a new born.

Let's use part of Mrs C.B. Platt's booties found in Tat-man's site, using TH's grammar for simplicity:

Note: The original pattern doesn't ask any thread size.

1. Begin at one end of the sole with a cloverleaf:
R1= 5DS - 2DS - 2DS - 2DS - 5DS CR
R2= 5DS +R1 2DS - 2DS - 2DS - 5DS CR
R3= 5DS +R2 2DS - 2DS - 2DS - 5DS CR
BT= PA 

    # Bare thread using Picot gauge A (1/8th in or 3 mm)
14 {
        R4= 5DS +R 2DS - 2DS - 2DS - 5DS CR RW
        # join to previous R's nearest free picot
        BT= PA 

        # Bare thread using Picot gauge A (1/8th in or 3 mm)
}

2. Finish at the other end of the sole with a cloverleaf:
R5= 6DS +R4 3DS - 3DS - 3DS - 6DS CR
R6= 6DS +R5 3DS - 3DS - 3DS - 6DS CR
R7= 6DS +R6 3DS - 3DS - 3DS +R4 6DS CR CTH
 

We have 2, 3, 5 and 6 double stitches. Let's find their 46%: 

2*46/100=0.92 rounding to near integer: 1 
3*46/100=1.38 rounding to near integer: 1
5*46/100=2.30 rounding to near integer: 2
6*46/100=2.76 rounding to near integer: 3

Now what? Subtract of course, size 10 is thicker than 20. 

Where you have 2DS minus 1 will be 1DS, 3DS will become 2DS, 5DS will become 3DS, 6DS will become 3DS and 3mm will become 2mm (sorry I'm really bad at imperial measuring system, hope you've got the idea).


The table is based on the threads I use, on the length of the shape tatted with those thread sizes and on double stitches:

Sizes 5, 8, 12 Presencia Cotton Perlé 
Size 20, 30, 40 DMC and Lizbeth
Size 10, 50, 80 Anchor

Thread size 3 was a sample that a tatter friend, Phyllis, sent to me when we were testing the first version of TatHelper. I don't really know what brand it is, guess it could be Lizbeth or DMC Petra. 

The table is incomplete, I have other thread sizes, other relations for BDS and everyday appears a new thread in the market. Probably it will never be completed because of it, experiment with yours. Remember that the tatted work depends not only on the thread, but on the tatter. 

Remember:
    percentage > 100, substract
    percentage < 100, add
    percentage = 100 smile




SIZE 3 5 8 12 10 20 30 40 50 80
63% 55% 42% 78% 54% 42% 40% 42% 33%



SIZE 5 3 8 12 10 20 30 40 50 80
158% 86% 65% 123% 84% 65% 63% 65% 52%


SIZE 8 3 5 12 10 20 30 40 50 80
183% 116% 76% 144% 98% 76% 73% 76% 60%


SIZE 12 3 5 8 10 20 30 40 50 80
241% 153% 131% 189% 129% 100% 96% 100% 79%


SIZE 10 3 5 8 12 20 30 40 50 80
128% 81% 70% 53% 68% 53% 51% 53% 42%


SIZE 20 3 5 8 12 10 30 40 50 80
187% 119% 102% 78% 146% 78% 74% 78% 61%


SIZE 30 3 5 8 12 10 20 40 50 80
241% 153% 131% 100% 189% 129% 96% 100% 79%


SIZE 40 3 5 8 12 10 20 30 50 80
251% 159% 137% 104% 197% 134% 104% 104% 83%


SIZE 50 3 5 8 12 10 20 30 40 80
241% 153% 131% 100% 189% 129% 100% 96% 79%


SIZE 80 3 5 8 12 10 20 30 40 50
304% 193% 166% 126% 238% 163% 126% 121% 126%

Going from a thinner to thicker thread would need a post?