Plating Techniques in Flat Knitting Machine
University of Moratuwa, Sri Lanka
Plating can be done in flat knitting machine. But to do so it’s needed to incorporate new knitting method specially for knitting plated structures. In this article I will be suggesting new method to manufacture plated fabrics using plating techniques in flat knitting machine.
The plan is to use double latch needle which has two hooks and latch at the same end of the needle. This can be readily installed in flat bed knitting machine with special yarn feeding device which feeds yarn appropriate to the needle height.
The method is simple. In plated fabrics the main problem of knitting is when knitting in one latch there’s always a tendency to yarn to twist with each other producing miss plate point. In our method we suppose yarn to be knitted in different latches and join them at the end.
At first a knocking over position of the double latch needle which is knitting a new loop. This is where the new loop is created. Since there are two hooks to knit two different yarns individually there’s no possibility to yarn for twisting with each other. The blue yarn which was knitted in higher hook is stay above the red yarn knitted in lower hook, maintaining plated structure.
At 2nd position where top hook is in tuck in position and lower hook is in holding down position. This position occurs when needle start to move upwards to take new yarn. In this moment we can assume with the correct geometry of the latch top loop is starting sliding down to the stem of the needle.
At 3rd position where lower hook is in tuck in position and both yarns are in same latch sliding down to the stem of the needle. In this particular occasion there is a high risk of yarn to twist with each other. So that lower latch geometry should be carefully designed to make sure that when top blue yarn is reaching to the lower latch the lower yarn which is red has slipped away from the lower latch and fallen in to the needle stem.
At 4th position where needle has come to clearing hight and on the way back yarns are fed in to the hooks. In here special thing to note is there are two yarn feeding heights as is appropriate to different levels of height they might remain when they reach to the yarn feeding position.
At 5th position where bottom latch is in cast in position and top latch is still to be closed. In here there’s something that taken in to consideration. Bottom and top latch should be designed in such a way that after reaching this position and when it further pulled down, bottom and top latch is functioning as they make a bridge for previous loop to slide off the needle, than again caught by top hook.
In this way there can be a possibility to manufacture plated fabrics.
There can be a difference with loop sizes because the loop created by bottom hook is having high holding down length than top producing larger loop sizes with bottom hook and smaller ones in top hook. But this will not be a problem when using elastic yarn like lycra or spandex. In such occasion lycra or spandex yarn can be fed to the lower hook so that even though the hook is producing larger loop size when needle let off both yarns from its stem elastic yarn stretch back to and gain normal loop size. This can be over come using two separate needles forming one loop by feeding yarns around both needles. And the loop size problem can be avoided in such situations because since there are two needles we can easily control knocking over height by using a cam resulting same loop sizes.
When needle is in cast in position there can be a danger of yarns to roll over each over each other and making a miss plate point. This can be avoided by using a sinker which comes between two yarns when top yarn is in cast in position. Since lower yarn is on stem and top yarn is in needle latch, in this position there is a ability to insert a special sinker between two yarns separating them. So that there won’t be a roll over situation when both are in cast in position.
Fleecy can be done in flat knitting machine, with some changes in knitting cam and yarn feeder system. When knitting a fleecy structure special thing to note down is that the first selection which is done while knitting is whether a particular yarn knit on a given needle. If the fleecy structure is 3 by 1 structure. Every needle after two needles should knit fleecy structure. So that knitting machine should have needle selection system to select needles according to the needle structure knitting. And when the selection is made second selection comes in that is when particular needle is knitting a fleecy stitch it should perform different knit movements. So that selected needle should perform those movements.
Sequence of Knitting or Knitting Method:
- Selected needle is raised to tuck height to receive the fleecy yarn. And sinker with two throat comes in and top throat one will be pushing the fleecy yarn to make a small loop while lower throat which is the larger one will be pushing the previous one.
- And then needle should be raised and clear all yarns so that it can take the tie in yarn
- And then needle should be taken to tucking in the latch position so that previous course remains outside the latch making without knitting a separate loop. This is how new fleecy tuck is made. So that cam must be designed in such a way it will make tucking in the latch
- The needle is again raised to tucking in the latch position in this way there will be tie in yarn knit over the previous given
- Needles finally withdrawn so that there will a new loop producing. This will be needing a very precise cam system.
Founder & Editor of Textile Learner. He is a Textile Consultant, Blogger & Entrepreneur. He is working as a textile consultant in several local and international companies. He is also a contributor of Wikipedia.