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Tag: Spiral or Twisted Needle Mechanics

Dose the twisted needle twist as it goes into the wool?

Dose the twisted needle twist as it goes into the wool?

Recently I was asked more questions about needles. (I do love finding out about needles, how they are used in industry and how we use them by hand. I hope you still have a bit of curiosity about them too, after all my enthusiastic chatting!) To answer the second question, I still want to get my hands on a forked needle (how can I be fair in my investigation if I don’t actually get my hands on one?) A quick review, In industry there are two types of structuring needles. Structuring needles are not technically felting needles (since they don’t make the felt) but are used to create surface texture on non-woven material.  One is the Forked needle, and the other is a crown needle (which we have chatted about before. If you don’t remember that chat you will find it here; https://feltingandfiberstudio.com/2022/07/19/a-question-about-crown-felting-needles/)    Since I have not had success locally finding a fork needle, let’s turn to the other question about needles. It involved one of the Needles found in the group of needles which do make the industrial Felt.

Does the twisted (also called a spiral) needle twist as it goes into the wool?

Ok, this is a question about mechanics, and how the needle works.  So let’s review the parts of a triangle needle and compare that to the twisted / spiral needle.

diagram of parts of a regular felting needle and a spiral felting needle1)Parts of a regular felting needle and parts of a spiral needle

We can see that all the usual parts are present with a spiral / twisted needle. The difference is in the working part. you can see both clearly have a triangular cross section in the working part but the spiral/twisted needle has that triangular shape rotating in the cross section through the working part.

diagram of a twisted needle close up2) Twisted Needle showing close up of working part

Let’s have a quick review of what shapes are most common in the cross section of the felting needles most often used by hand needle felters. Our most common shape is the triangle, but the 3 and 4-sided stars are also quite available. While some are not as common, there is a spiral or twisted versions of each of the three main shapes.

Common Cross sections of working parts of main felting needles3) Common cross-sectional shapes of felting needles

Let’s go back and look specifically at the spiral or twisted shaped needle. If you look at the cross-section of the spiral at various spots, you can see that it is a triangle rotating around a central point.

4) Cross sections of a twisted needle across section of the working part   5) Looking from the tip up the needle through the segments shows how the tip of the triangle changes position up the length of the working section. (i have updated diagram 5 to more clearly show the location of each edge.)

As you know with all needles, the barb is located on the edge of the needle. With most needles, the barbs are located vertically, one above the other, along each edge. There will be one, two or three barbs per side depending on the specifications for that needle.

The exceptions, for vertically stacked barbs, at present are; the Crown needle (which only has one barb per edge), the fork needle (that has no barbs and a cylindrical shaft) and the spiral needle (whose barbs follow the curve of the needle’s edge).  The last exception to the vertical barb rule, is more of a technicality; the conical needles has barb aligned vertically but because of the taper in the working part, it will engage fibre laterally (we can chat about that further in another note. If you are curious?)

So as the spiral/twisted needle is inserted into our felt how is it engaging the fibre it catches in its barbs?  it is grabbing segmentally as each barb enters the web of fibre. It will create more of a circular Spiral of engagement rather than the three barb points a regular triangle needle will engage.

Here are two ways to visualize how the needle’s barbs are grabbing the fibres as they enter the web. As you know the barb will engage (grab) the fibres it encounters which will be at or close to the surface of the felt web of fibres. For clarity of the diagram, I have had the barbs that are deeper in the web engaging with fibre closer to the barb. If I had more correctly illustrated the crossing fibres, which the barbs are affecting, all the fibres would be at or near the surface layer(and the diagram would be a confusing-looking mess!)

diagram of how barbs on sides 1 to 3 interact with fibers as the needle is inserted6) How each barb distorts the web in a different position as the needle is inserted

I am hopeful you can see the spiral engagement of one edge, then the next, then the third. I have added colours (Red, Purple and black) to the edges to try to make it easier to see how the spiralling of the triangle shape interacts with the order of the barbs as they encounter the fibres.

Here is another way of looking at the order of engagement of the barbs around the centre of the needle.

Diagram the order of barb engagement as the needle is inserted into the felt7) The order of barb engagement

 

A few more particulars about Spiral Twisted needle

If you read the technical details on the Groz-Breckert site, (one of the needle manufacturers, this one headquartered in Germany) you can find that Spiral/twisted needles are available in:

  • gauges from 38G to 42G
  • Length of 3 or 2.5 inches
  • Usually has 2 barbs per side, but only one barb style is common
    • has a modified barb arrangement (spiral location around the needle)
    • the needle placement gives higher fibre engagement
    • the needle is a bit stronger from barb placement (in the felting machine, both the “machine direction” (8%) and to a lesser degree “cross direction”(4%).)  It may be a bit less prone to breakage with small vector changes if used by hand!  it would still be better to try to go out at the same angle that you inserted the needle.
    • it is listed as having more chance of splitting fibres when using microfibers (we should be ok we tend to take our frustrations out on natural fibres such as wool, silk, alpaca, dog or cat hair)
  • Fiber transport is listed as “Substantially Higher” for a twisted needle, rather than a regular (triangular) needle (of the same gauge and barb shape).
    • It can move about 10% more fibre than a standard felting needle with the same barb dimensions. (It is More Aggressive when compared to the same gauge and barb style of a standard needle)
  • Uses industrially are; Automotive sector (visible areas such as trunk lining and other non-woven surfaces) and Filtration fabrics.

Doer Needles from China sample of 38G Spiral needle8) Doer Industries (China) 38G-222 Triangular Spiral (they also have 40G-222 with the same barb spacing.)

Hand Needle Felting Uses;

  • Good fibre movement(more than a Triangle needle of the same gauge and barb type)
  • Good for compacting fibre or generalized initial sculpting. You may find it a bit aggressive for fine detail at larger gauges. Try a finer gauge if you find it more aggressive than you desire.
  • Used on a sharp angle (surface work), good for catching loose fibres that need embedding
  • Good with short fibres will grab and embed them quickly
  • If you require a 42G needle but don’t have the patents that such a fine gauge requires, a 42G Spiral needle may be for you. (it’s a little bit faster!)

Watch for;

  • May not be as effective when multiple needles of this type are used close together (held together with an elastic or some holders with close spacing) you may find with medium to longer fibres you are trying to engage the same fibre with adjacent needles

Let’s consider the question, “So, Dose the twisted needle twist as it goes into the wool?” What do you think so far?

I know you will remember that the needle itself is descending in a straight line, it is not moving other than in one vector (up and down in this depiction). There is no rotational component of insertion necessary. The movement of the needle descending into the fibre is creating the spiral engagement (grabbing) of the fibres. So technically, the needle is not turning in a spiral but the engagement of the fiber is interacting in a spiral. Each barb has not rotated but descending in a straight line. The fibre cot by the barb is also descending in a straight line, but as each barb above it engages fibre it will be grabbing a bit that is offset from the barb below it. This gives an illusion of spiralling while engaging a more even amount of fibre surrounding the needle than a regular triangular needle would (with barbs stacked vertically in 3 spots). So the answer would be “the needle no but the fibre looks like it is from the surface but is actually not.” Well, now you are likely disappointed after such a long explanation. But there is one more thing to consider.

That being said, it is possible to turn a needle as you insert it into the felt. Rotating the needle can be used to grab flyaway fibre, or catch something that is loose on the surface. It involves rolling the needle between the thumb and first finger. This is not a good long-term technique since it is engaging little muscles that get tired more quickly than larger muscles and can be strained easily when compared to larger muscle groups. Instead of spinning a triangle needle trying to grab fibre, you may find that a Spiral/Twisted needle is a bit easier to engage loose fibre.

I hope this gives you an overview of the spiral or twisted needles. Their a bit more aggressive than an equivalent triangular needle,  so they may be helpful for finer gauge work if you are not patent. I hope, if you get the opportunity, you will try them for 2D or 3D felting.

PS; the needles will work without having to know all the details of how they work, but knowing may give you creative ideas and inspire you to use them to solve challenges while you’re felting. Even better, I did not add any exam questions at the end!!!