Curtain making (Pleating by Design)

[Classical Genesis]

An introduction to Pleating by design
A PDF document of this lesson is free to download by clicking in the curtain......................
If you can't download it then please PM me and I will email a copy to you

Now we understand, from the previous tutorial, what pleats and spaces are and we know the order in which the flat bits form out through the head of the curtain. We need to start looking at where the measurements and proportions actually come from and to do this we will need to go back nearly a thousand years to the time of the Norman conquests and the holy wars. Armies and traders carried new products back from far flung lands and amongst these newly discovered possessions came a fabric from Damascus. The fabric was woven from a single colour yarn and the warp and weft fibres had been skilfully woven so that a series of raised patterns repeated across the face of the fabric in regular blocks often with a diagonally repeating pattern beneath it. The world knows this fabric as Damask.

In 1801 when Jaquard built his new loom attachment he constructed his loom so that he could associate four separate warp threads, in sequence, from each of the horizontal pattern repeats to the each punch card. As each card represented one pass of the shuttle carrying one weft or fill yarn across the width of fabric he could produce four pattern repeats across the width of fabric using only one pattern card. By this method he found that he could faithfully replicate these ancient patterns.

Traditional Damask fabrics are not always produced with four pattern repeats and they don’t always have a diagonal repeat on each half drop. However the patterns are configured you will usually find that the patterns are repeated in multiples of four, so four, eight, twelve (rare), sixteen, thirty two and so on. Whatever the number we can always guarantee to be able to use the patterns to break the fabric into quarters with an identical pattern in each quarter.

You can see below a modern two colour Damask woven in lines of four patterns. The horizontal half drop line is symmetrical and consists of three patterns with half patterns running up to the selvedges. We are going to use this typical four and three pattern structure to start to develop an understanding of the system used in pleating by design.



Not all fabrics which have four pattern repeats contain such symmetry in pattern design as this Damask. Whilst the pattern distribution may be the same the actual pattern or picture may look very different when the chosen portion is placed at the head of the curtain and folded into the pleats. Where a curtain is being made to fit on a pole with the pleats visible, you will want to choose the part of a pattern or picture which best suits the shape of the type of pleats you intend to form.

If you are deciding to form double or triple pleats then you may well find that symmetrical patterns sit a little better within the folds whereas picture type elements can be displayed unhindered around the curving surfaces of a goblet pleats.

In the next post you will see the portion of the design which I chose to place on a sample curtain where double pleats were formed. I very much doubt that I would have chosen to place the same portion of this design on the front of a goblet pleat.

................................Clive

[Classical Genesis]

Pleating by design continued

Here is a fabric which contains a pattern which is distributed in the same form as the Damask but you will note that the pattern itself is not a symmetrical one. This presents a little more challenge when it comes to placing the patterns onto pleats.



I am going to set out this fabric as if I we are going to cut the first drop for the right hand curtain, working from the leading edge on the left.

1, I will start by identifying the horizontal line which I would like to use. I will assume that I am going to form a six inch deep head. I will use two long rulers six inches apart and move them together up and down through one pattern repeat until I have chosen the portion of the pattern or picture that I would like to fold into the pleats.

2, The horizontal pattern repeat of this fabric is 350mm (35cm) and I am going to set the pleats out to 200mm (20cm) for one pleat and 150mm (15cm) for one space. My half space will, therefore, be 75mm (7.5cm), my centre overlap will be 3omm (3cm) and my side turning will be 70mm (7cm)



If I try to place my first pleat on the line of four patterns starting on the left side of the fabric then I can not get a half space, a centre overlap and a side turning from the remaining fabric to the left of it so I must move my first pleat over to the next pattern.

At this stage I can choose to move along the same line horizontally or I can drop down diagonally into the half drop repeat. With this fabric it works the same whether I simply move horizontally or drop to the diagonal repeat. Which ever I choose I will obtain three pleats from this width of fabric. The difference comes only if I wish to join my fabric on the selvedge. Moving in along the line of four full patterns the selvedge join will fall centre of a space whereas on the half drop line I have chosen the the selvedge join will fall centre of a pleat. This makes little difference to me as I will never place a fabric join in either the centre of a pleat or the centre of a space, unless I am forced to do so as both are taboo in my view. You will note that I have marked a point to the right where I wish to make my face fabric joint, this point is 10mm (1cm) outside the vertical stitch line of my pleat which guarantees that my fabric join will always be tucked in behind my pleat and that it will run down the side of the folded fabric through the body of the curtain. As I set out further widths my points of joining will fall progressively to the right side of pleats on the right hand curtain and to the left side of my pleats on my left hand curtain. You will find that as you start to carry our exercises in setting out that you will only ever obtain three pleats from each width of fabric. This is because you will use the first quarter width from the leading edge to house the flat bits which cross the centre line of the pole and form the side turning and a quarter width on the last drop to form the extra flat bits which return to the wall (optional) and form the side turning at the back edge. The centre drops will only reveal three pleats because I will squander one quarter width to place my join where it will always remain invisible.

The design works well but it is all well and good to set out a sample to perfecting pleating proportions. In the real world we have to measure a pole or track, make all the necessary allowances for the extra flat bits and calculate the actual sizes of the spaces required to sit along the pole. These adjustments will not, however, alter the positioning of the pattern on the pleats. Only the pleat space proportion will be adjusted by the calculations.

The next post will cover basic calculations. It doesn't get any easier than this but boy can it get harder.

..........................Clive

[Classical Genesis]

Pleating by Design continued


Making calculations for patterned fabric.

The use of the fractal proportion of 4 over 3 (displayed as a fraction) is relevant to the both patterned and plain fabric headings. Where there is a horizontal pattern repeat of 350mm (35cm) we will make of this one pleat and one space. The fractal proportion of 4 over 3 relates to 200mm (20cm) for the pleat and 150mm (15cm) for the space but if the horizontal pattern repeat were to be 370mm (37cm) or 330mm (33cm) then the pleat space measurements would vary accordingly if the same proportion were to be maintained. The 4 to 3 pleat space ratio is, therefore, simply a proportional perception.

I like to refer to this perception as Pennington's - Perfect - Pleating - Proportion

So how do we convert our perception of this pleating proportion into a practical application? For the answer to this question we must look directly to the method of measurement and calculation.

Let’s look at a straightforward situation. You are visiting a clients house to measure up for a pair of curtains to fit onto a curtain pole. The client has already purchased the fabric for the curtains and you are praying that she has purchased enough of it. After a discussion with the client a viewing of the room and an inspection of the fabric you decide that you would like to see a pair of full length curtains which have elegant double pleats of around 150mm (15cm) in height and so you set to work

Your measurement for the pole is taken from 1cm past the outside ring to the same point at the opposite end of the pole. The drop of the curtain is taken from the underside of the large wooden or metal curtain ring to the surface of the carpet.

These measurements are:

Width = 2.720m

Drop = 2.400m

So, we will deal with the pleating arrangement first. Our aim is to get as close to the perfect pleating proportion as possible.

The perfect proportion, as we know, is 200mm (20cm) for the pleat and 150mm (15cm) for the space but we will only need to consider the spaces for this exercise.

The space is made up from 2 calculable elements:

1, the flat space

2, ease

The ease equates to about 5% of the total space.

5% of 150mm = 7.5mm. As this is a little impractical we will use 7mm as the proportion of ease for each space. The flat space, therefore, becomes 143mm and the ease element is 7mm

We can only use the flat space measurement to calculate with because we will need the ease to slacken the spaces when the curtain is hung.

the pole length is 2.720m.

2.720m divided by 143mm = 19.02

This indicates that the 2 curtains would have 19 spaces which, of course, is silly as we can’t divide 19 by 2 so we have to calculate either side of this value.

to determine how many spaces we will use for each curtain.
20 divisions will provide 10 spaces for each curtain and 18 divisions will provide 9 spaces for each curtain. We will carry out both calculations so that we can choose which number works best for us.

2.720 divided by 20 = 136mm

2.720 divided by 18 = 151mm

We need to take both of these measurements and look at the pleat space proportions they impose on the
design. we must of course add back the ease into each of the spaces that we took out before we started the calculation.

Our pleat space allowance is 350mm so this will give us pleat space proportions of either:

@20 divisions = 136mm + 7mm = 143mm

space @ 143mm + pleat @ 207mm = 350mm


@18 divisions - 151mm + 7mm = 158mm

space @ 158mm + pleat @ 192mm = 350mm

These pleat/space proportions vary a little and I would be satisfied with either at first glance but we need to look a little further into these options to see what might influence which one we chose.

Firstly there may be a an issue of the type of pleat chosen. A double pleat is folded into 4 flat sections whereas a triple pleat is folded into 6. I would much prefer to have a larger pleat allowance for triple pleats as the texture of the finished pleat line will be a little deeper and the pleats look a little bolder if there is more fabric to fold with.

Goblet pleats can look a little odd if the cylinder shape is too slender.

Double pleats are more tolerant and tend to look pretty good whichever side of the equation you go.

One of the more important reasons to make a choice can be the amount of fabric which each of the pleating arrangements will take to complete the project. If you look at the setting out sketch in the second post of this thread you will see that out of this width of fabric I can only obtain 3 pleats as the additional flat bits in the form of the centre overlap and the side turning must be taken from the first quarter of the fabric. The positioning of the fabric joining will also determine that I will only get three pleats from my second panel of fabric because the pattern will need to be matched within the first quarter. The last panel of fabric will also only provide me with three pleats because I will need to take my side turning and possibly a return to the wall at the back edge of the curtain from the last quarter. This recurring loss of one quarter of the width of fabric is ever present in pleating by design. Calculations will normally be based on obtaining 3 pleats from each width of fabric with each pleat/space portion representing one quarter of the width.

In the case of the calculations we have just made you will see that @ 18 divisions each curtain will contain 9 pleats and the number of fabric widths taken up by this will be 3.

If one were to choose the first option of 20 divisions then the number of fabric widths required would jump to 3.5 which would increase the fabric order by one width split between the two curtains.

The other difference between these to examples is that 18 divisions provides 9 backward and forwards folds in the body of each of the curtains and 20 divisions will provide 10 folds for each curtain which will make the body of the latter curtain appear to be a little fuller.

If the fabric, purchased by the client in this case, is sufficient to provide only 6 cut drops then you would either be stuck with 18 divisions or the client would need to obtain more fabric. Most clients find it difficult to get their heads round the amount of fabric required to make up curtains pleated by design let alone be asked to provide additional fabric to satisfy the whim of a curtain maker who simply wants to see slightly larger pleats. In any event the amount of fabric required for the job will need to be agreed with the client.


CONTINUED IN THE NEXT POST

[Classical Genesis]

CONTINUED FROM PREVIOUS POST

Calculating the fabric requirements for patterned fabric

To calculate the total fabric requirement for this project we need to take the finished drop of the curtain and add to it a heading and hems allowance.

The standard allowance for the heading and hems is 300mm (30cm). Out of this allowance 200mm (20cm will be used to make a double 100mm (10cm) hem and 50mm (5cm) will be needed to turn over the Buckram at the top of the curtain. This leaves 50mm (5cm) spare which can be used as a trimming allowance at the top and bottom of the curtain or could, with very accurate cutting, be added into the bottom hem on extra long curtains.

When we calculate the fabric requirements for plain fabric curtains we can simply add the cutting allowance to the finished drop and multiply this by the number of drops required, rounding up to the nearest whole metre.

When we calculate the fabric quantities for patterned fabric curtains the calculation must be based on adding up the number of vertical pattern repeats required to make each cut drop and then rounding up the number to the next pattern repeat so that all our patterns fall in a line at the top of the curtain. Once the total number of repeats has been established then one more pattern repeat is added. The reason for adding this additional pattern repeat is that when you first unroll the fabric on the bench and before you take your shears to it you must select the point across the fabric where you intend to make your line of pleats. The fabric suppliers will not know what you have in mind so they will cut at random, from the roll in their store, the amount of metres you order. From the top of the randomly cut fabric to the point you determine your pleat line can be anything up to a full pattern repeat so you must make an allowance for this in your final calculation. This is why you order one extra pattern repeat. After the final number of repeats has been calculated it is converted back to metreage.

These calculations apply to patterned fabric irrespective of whether you are pleating by design or making plain curtains with heading tape. To complete the calculation you will need to know -

1, How many widths of fabric you require to make your curtains.

2, The vertical repeat of the fabric.

A good tip is to always measure the pattern drop from a sample of the fabric. Don't be hoodwinked into using the manufacturers stated pattern repeat as you will find that 50% of the time it is wrong.

An example calculation would look like this

Finished drop of curtain = 2.400 - H&H allowance = .300 Cut drop = 2.700

The vertical pattern repeat is 510mm (51cm) so we will divide this into the cut drop of the curtain.

Cut drop 2.700 metres divided by 510mm (51cm) = 5.29 repeats

Round up 5.29 repeats to 6 and multiply this by the number of widths we need to make our curtain. For the sake of this exercise we will say that we need 6 widths of fabric to make our curtains.

6 repeats multiplied by 6 widths = 36 repeats

You need to add in 1 further pattern repeat which will be your setting out allowance.

36 repeats plus 1 = 37 repeats

Multiply the number of repeats by the measurement of the repeat and round up to the whole metre.

37 multiplied by 510mm (51cm) = 18.870 rounded up to 19 metres

You will need to buy 19 metres of fabric to make your curtains.

I do appreciate that these calculations are difficult to learn by reading a piece of paper but this is the only medium I have outside my classroom to offer some insight into the world of pleating by design. I hope that some of you will find the post useful and post any questions you might have. Meanwhile I had better get back to completing the other curtain making thread.

.............................Clive

[Classical Genesis]

Just looking through this thread and I realised that I had forgotten to provide a picture of the finished curtain made from the setting out design above, silly me, just click on them and they get bigger

This is a typical example of less is more, When you set out folded pleats try to pick areas of the fabric that can be see as patterns rather than pictures as they distribute more evenly through the folds of double or tripple pleats much better than pictures do. Save the picture elements to display on flat or curved planes like box or goblet pleats.

.... Clive