felicity
Posts: 662 | About shrinkageMar 19, 2014 10:25:20 GMTwolgelukkig likes this Post by felicity on Mar 19, 2014 10:25:20 GMTWe were talking with halay about shrinkage and I decided to post our calculations and examples here just in case somebody's interested. Of course this is my understanding of the matter. In felting shrinkage is the difference between size of wool you've laid and the size of the resulting piece of felt. Example:if you lay the wool at the template 100 cm and get a felted piece of 70 cm that your shrinkage is 30% (100-70)/100. % of shrinkage is different depending on wool and how you do your felting. That's why you need to make a sample before you start important project. After you know the shrinkage you can calculate the size of template. Example:If you want to know how big template should be to get the size you need you do calculations backwards: You want a template for the 53 cm felt. I hope it's not too complicated... |
luvswool and dyestuff
So happy to have found this site! I live in Chicago and am a retired educator. Hoping to share! Posts: 2,143 | About shrinkageMar 19, 2014 13:01:09 GMT Post by luvswool and dyestuff on Mar 19, 2014 13:01:09 GMTFelicity, I am very interested in shrinkage rates but have not yet had to deal with it, since I am in the learning stage. When I get ready to do "important" projects, this is definitely a calculation I wiil need to understand. Having not yet done many samples, I am not ready for the big projects. I seem to do okay with scarves and smaller items, but a large sculpture or vessel will require some math exercises. Thanks for posting your shrinkage calculations! |
Cathy |
About shrinkageMar 19, 2014 20:27:48 GMT Post by Teri Berry on Mar 19, 2014 20:27:48 GMTFunny this should come up today, I spent a chunk of yesterday evening trying to set up an Excel spreadsheet that would calculate both shrinkage rate (I prefer to work with total area rather individual lengths) and what you starting size needs to be to achieve a predetermined size. I will attempt to attach it here (not sure if the forum accepts spreadsheets shrinkage calculator.xlsx (14.14 KB) | |
)- you are more than welcome to use it to your heart's content.Pandagirl
Posts: 4,885 | About shrinkageMar 19, 2014 21:17:27 GMT Post by Pandagirl on Mar 19, 2014 21:17:27 GMTTeri, you are a woman after my own heart. I make notes and calculate the shrinkage rates based on each project and how I roll, rub and full each one, but hadn't gotten around to making a chart. I can open the chart just fine. It may be helpful as you expand your experiments to note the type of wool, silk, weight, etc. not all wool and silk shrink the same. I dyed some china silk yesterday along with some silk gauze and both shrunk in the process as well. But not in the same way. Thanks for the chart! |
Last Edit: Mar 19, 2014 21:18:25 GMT by Pandagirl Marilyn Nelson |
felicity
Posts: 662 | About shrinkageMar 19, 2014 21:19:30 GMT Post by felicity on Mar 19, 2014 21:19:30 GMTThank you Teri! There is something in the air I suppose... |
Last Edit: Mar 19, 2014 22:04:54 GMT by felicity |
Teri Berry
Guildford, UK Posts: 763 | About shrinkageMar 19, 2014 22:46:20 GMT Post by Teri Berry on Mar 19, 2014 22:46:20 GMTMarilyn, it sounds like you are far more disciplined than me, I have a stack of about 30 sample squares that I still need to label up with what they are and their shrinkage rates.... There's just too many far more interesting things vying for my time |
luvswool and dyestuff
So happy to have found this site! I live in Chicago and am a retired educator. Hoping to share! Posts: 2,143 | About shrinkageMar 19, 2014 23:21:30 GMT Post by luvswool and dyestuff on Mar 19, 2014 23:21:30 GMTVery impressed by you ladies--calculations, spreadsheets and notes on techniques, shrinkage rates and materials! Phew! |
Cathy |
About shrinkageMar 20, 2014 21:25:46 GMT Post by Shepherdess on Mar 20, 2014 21:25:46 GMTFelicity, great job explaining the calculations. Your spread sheet worked for me Terry. I appreciate knowing people like you. I am a bad note taker or very good at being precise. It's one of the things I like about felting I can usually make something shrink a little more or stretch it a little. I know if something is going to shrink 1/3(33%) my template has to be 50% bigger. If it will shrink by half(50%) it needs to be twice as big(100%, bigger). Its a good rule of thumb. I work it out for things like hats, vests and new projects but not for scarves. I know an 8 foot start length will work out right. | |
Ann |
liene
Posts: 17 | About shrinkageMay 22, 2014 9:47:52 GMTzed likes this Post by liene on May 22, 2014 9:47:52 GMTshrinking % is always so tricky especialy when combining sveral types of fiber (tops and fleece for example. also it is very important when making the example/test felting piece to make it as thick as the project will be, thicknes - amount of layers is important |
halay
http://www.ipernity.com/home/724735 Posts: 1,380 | About shrinkageMay 22, 2014 11:23:04 GMTzed likes this Post by halay on May 22, 2014 11:23:04 GMTTeri Berry, I have difficulties opening your shrinkage calculator.xlsx (perhaps my old computer does not recognise files with x in the end. I would agree with Liene in that you need to make a sample before you start a "serious" project considering the thickness, i.e. number of layers, therefore a single formula may not work but is a good orientation. This is such an important topic that it calls for writing and posting a tutorial. Felicity and/or Teri berry, would you be willing to write one? |
Pandagirl
Posts: 4,885 | About shrinkageMay 22, 2014 16:10:10 GMTfelicity likes this Post by Pandagirl on May 22, 2014 16:10:10 GMTHalay, I think you have to have one of the newer versions of excel. Perhaps Teri can save it as an. Xls file and you'd be able to open it unless some functions would be lost. I think a tutorial is a good idea, but definitely when working on new or unknown fibers a sample is the only way to go.. |
Marilyn Nelson |
felicity
Posts: 662 | About shrinkageMay 22, 2014 17:23:07 GMTzed likes this Post by felicity on May 22, 2014 17:23:07 GMTVery much agree with Marilyn! I wouldn't mind to write a tutorial but what exactly is needed? All my formulae above were about calculation a shrinkage starting with making a sample. There are so many points to consider: |
Pandagirl
Posts: 4,885 | About shrinkageMay 22, 2014 17:51:15 GMT Post by Pandagirl on May 22, 2014 17:51:15 GMTYou're right Felicity there are so many variables! |
Marilyn Nelson |
zed
Posts: 5,341 | About shrinkageMay 23, 2014 8:47:58 GMTPandagirl likes this Post by zed on May 23, 2014 8:47:58 GMTI have a section in my Wet Felting/Notebook cover tutorials that explains as simply as possible how to calculate the shrinkage when making a sample and how to use that info to increase your template/layout size. I can edit it and email it to anyone who wants it? |
Shepherdess
Ottawa, Canada Posts: 7,397 | About shrinkageMay 23, 2014 13:26:47 GMT Post by Shepherdess on May 23, 2014 13:26:47 GMTWhen I did boots we had to make a samples to the thickness we wanted the boots. Then no only calculate the shrinkage but calculate the weight of wool need for the project, using the square inches of the whole boot. |
Ann |
