Roll-Pinning is a traditional tailoring technique, used to assemble two layers of fabric so they can be treated as one layer afterwards. In corsetry that means the outer layer of a corset (fashion fabric) is attached to the strength layer of the corset (coutil, twill, etc…), panel by panel, before stitching all the pieces of the corset together. In general I would recommend this technique for any fabric that can't be ironed very well, like brocades or quilted fabrics, wool with a certain amount of volume, leather, or pvc. For materials that can be ironed without any problems, I personally prefer fusible interfacing to attach the layers, as it is much quicker than roll-pinning.
Also, I find it a bit tricky to roll-pin very thin and lightweight fabrics like silk, satin, and taffeta. They tend to wrinkle a lot and it is hard to achieve a smooth corset surface with this kind of materials, so I prefer fusing them to the the coutil base to save time and nerves. For special materials like those mentioned above, the good old tailoring method of roll-pinning is still very useful, though, and definitely something a corsetmaker should have in his or her repertoire.
But now let's get started with the method itself: I will demonstrate it with a basic black underbust corset, made from black diamond quilted silk, and later with a longline, black pvc, overbust corset.
Roll-pinning can either be done by pinning the layers together or by hand-basting them, which I personally prefer. This way the layers are secured and you don't have to worry about a ton of pins, which also might fall out while handling the corset panels and stitching them together.
As you can see on the technical drawing above, the outer layer needs some extra width compared to the inner layer, so it lies flat and smooth once the seam allowances are turned over and pressed.
And with this point we come to the main purpose of roll-pinning...
If both layers are assembled lying flat on the table, the outer layer would be too small on the finished corset, causing unsightly wrinkles in the strength layer. We have to add the right amount of ease in the outer layer to make the corset lie smooth against the body in the end. That certain amount of extra width in the outer layer is especially important for the curved parts of a corset (bust and hips), as round shapes increase the difference between the two layers.
So the big question is: How do we determine the exact amount of extra width we have to add to the outer layer, when attaching it to the strength layer?
I heard that some corsetmakers just add width intuitively, but personally that didn't work so well for me, especially when the layers don't have any elasticity at all. A slightly stretchy fashion fabric possibly could be attached to the strength layer without extra width, as such a material will stretch and follow the curves as much as necessary, but the less stretchy and the stiffer a fabric is, the more careful it has to be roll-pinned to avoid wrinkles in the layers. During my traditional tailors training we also covered this topic. The method I have learnt there works very well for me and I have successfully used it for many corsets since then.
So here is a step-by-step guide of how to assemble the layers of your corset panels:
Firstly take care to cut the seam allowance of the fashion fabric a bit wider around each corset panel. You will need this extra fabric for the roll-pinning process later.
After you have cut both layers of your corset, you will then need a tailor's ham. Personally, I prefer a bigger one in the shape of a torso:
But there are also kidney-shaped or egg-shaped ones available:
If you don't have a tailor's ham you can alternatively use a solid cushion, or any other round, solid shape you might find suitable. The better the curves of this tailor's ham match the curves of your finished corset, the better it will work for roll-pinning.
If working with a fabric where pattern matching is required – like the diamond quilted silk I used for my first sample – I begin with hand-basting the center front and center back line in the first and the last panel and the waistline in all panels to make sure, the fashion fabric is perfectly in grain and the pattern in the right place.
In general, a basted waistline helps to keep the grain straight and to prevent the layers from shifting during the next steps.
The third step is to place both layers onto the tailor's ham in a way that the curves match the curves of the body. That means the hip area should be placed on a very round part, whereas the waist area should be placed over a part of the tailor's ham that curves inwards.
With a cushion you can only do the areas that curve outwards, but it should still get you there with some practice. Once both layers lie smoothly in place, you can start basting them together with a pad-stitch across the panel, to assemble both layers and to secure the curves.
When finished, carefully remove both pieces from the tailor's ham and put it on the desk with the fashion fabric facing the workplate, but don't smoothe the layers now, as they already contain some extra width from the curves of the tailor's ham.
The extra width for each seam you can gain now through folding the seam allowance over, while basting the layers together.
Holding the seam allowance in a folded position while basting makes the outer layer wider than the inner strength layer and adds just the needed amount of ease to your fashion fabric.
This procedure of “rolling” the seam allowance over during basting is also the origin of the term “roll-pinning”.
I also would recommend you baste not directly on the seamline, but about one millimetre outside of the seamline. Now the thread doesn't get caught in the seam and won't be visible from the outside later. On the top and bottom edge of the corset, however, I do baste directly on the line to mark the edge of the finished corset on the outside. This comes in quite useful when trimming the edges of the corset later, during construction.
Using the technique described above, you now can work around each corset panel, until all pieces are done. When lying on the desk, any of these pieces should be shaped instead of lying flat on the surface, due to the extra width added by roll-pinning.
Now you can treat the layers as one and go on with the construction of your corset as usual.
After stitching two panels together, the basted line next to the seam can already be removed, the seam allowance trimmed and so on...
If the layers are not perfectly smooth after stitching the panels together, you can usually smoothen small wrinkles with the steam iron, gently pressing and steaming the curves over your tailor's ham to bring out the shape of the corset.
(Please take care, though, in case your fabric doesn't tolerate steam ironing. Best test with some material samples, to see how your fabric responds to steam and pressing, before trying this with your original corset. In general this process works better with natural fibres, which respond better to the steam iron. Heavier, more voluminous materials are also more forgiving, compared to the already-mentioned tricky silks, satins and taffetas.)
After removing the pad-stitching on the stitched panels, they now lie smoothly - and without any wrinkles - on the dress form.
Something I would also like to introduce at this point, is the option of creating additional boning channels which are not visible on the outside of the corset, apart from the boning channels on the seams.
Assembling the corset layers without fusing gives you the option of sewing bone casings to just the strength layer of the corset only, instead of stitching through all layers. Later, these seams will be covered with the outer layer (fashion fabric) and therefore won't be visible any longer.
For this purpose you have to sew the internal bone-casings onto the panels, before roll-pinning the fashion fabric to the strength layer. You can use, for example, twill tape, herringbone tape or special tubular boning tape to create the channels in the desired positions. Mark the position of your additional bone-casing on the inside of the strength layer and then pin the tape in place and stitch it onto your panel.
Afterwards, go on with the roll-pinning of the panel as described above. From the outside the additional bone-casing in the center of the panel won't be visible at all.
The bone casings in the seam allowances will be created later, once all pieces are roll-pinned and sewn together with your usual preferred construction methods.
If you prefer a structured look with visible seams anyway, just construct your corset with the roll-pinned pieces as described above and then stitch through all layers to create the boning channels.
Now the technique with the tailor's ham - as described above - works perfectly well for woven textiles, but with leather or pvc materials you have to go a slightly different route, as the step of basting through the layers with the pad-stitch would leave visible stitch marks on the corset panels (that also might apply for some silks and especially taffetas – please test basting on a small piece of fabric before getting started with the original corset pieces).
For that reason, I will now describe my method of roll-pinning leather, synthetic leather and pvc materials:
The first steps are the same as for woven textiles. Cut both corset layers, making the outer layer slightly bigger around the seam allowances, to make sure there will be enough extra material for the additional width. However, instead of pad-stitching the two layers together on the tailor's ham, I use basting spray to keep outer layer and strength layer in place while roll-pinning.
Before using any kind of basting spray or spray glue, I would again recommend to test the glue on a small sample, as some glues might show through on the outside or even ruin the leather / pvc. Make sure to choose a spray glue which holds the layers together without leaving any marks – neither on the outer layer, nor on the strength layer, which will be directly on the body or only covered by a thin lining once the corset is finished.
Personally I had good experiences with Prym spray adhesive, as well as 3M Photo Mount spray glue, which usually is used to affix photos to cardboard backgrounds.
You might not be able to find these two brands in your area, but I'm sure that there are a lot of other suitable products available online and in fabric or haberdashery shops.
To assemble both layers, first place the strength layer piece on the tailor's ham, as described above for fabric corsets.
Then spray glue the back side of the leather / pvc outer layer and carefully place it onto the piece on the tailor's ham. Gently press the layers together and smooth it.
Now you can go on with basting around each seamline, as described for fabric corsets.
In my experience, pvc and any other synthetic materials are less forgiving than leather or woven fabrics, so it might be necessary to adjust the roll-pinning on some seamlines once the first seamline is done. Thicker outer layers need even more width, which isn't always there - even with carefully roll-pinned panels. For that reason I begin the corset construction by always stitching a pair of panels together, so every second seam is still open and possible to adjust.
After topstitching the seam allowances (since pressing is not possible for leather and synthetic materials), you can check if it is necessary to reopen the second side seam and roll-pin it again. If there is already enough width in the panel from the first go of roll-pinning, just continue to stitch the panels together. This may cause a certain amount of extra work and time, but it definitely helps to avoid wrinkles, which in my opinion look especially bad in smooth and shiny materials such as pvc.
When choosing the material for your corset, you might keep in mind, that heavier materials wrinkle and crease less than lightweight materials. On the other hand thin materials require less width and therefore less likely require a second round of roll-pinning.
Also, most thinner leathers and some pvc and synthetic materials are slightly stretchy, which again makes it easier to roll-pin them, compared to heavy, completely non-stretchy leathers or pvc.
Finally - as for fabric corsets - again the option of hidden internal bone casings is available for leather and pvc corsets, without any changing in technique.
I hope this guide explains the pros and cons of roll-pinning, and how to use this technique for different kind of materials, in an easy way.