It produces crisper creases, at hems or along seams where you want them to lie flat and smooth.
The way to use a clapper is to first press a seam or hem with the iron using steam, then press the clapper onto the area that's hot from pressing and either just hold there some seconds for easily creasing fabrics, or press down a bit harder for fabrics that crease less easily. The raw wood of the clapper will absorb moisture and heat and leave the seam or hem cool to the touch - and the material will "remember" to hold this crease.
You can use it on hems, seams like shoulder and collar seams and it works beautifully on darts too.
I wouldn't have thought so myself before trying it, but it does work - the waterfall collar jacket I am making at the moment does look just that bit better than it would without using a clapper. I am really pleased with the result!
It is made from hardwood, has a handy groove along both longer sides for easy handling:
And one side is narrower than the other:
As with everything, the best gadget does not guarantee an absence of user error - which is what I managed today: I was using my newly purchased clapper with abandon and delight on the seam between sleeve and body - to get the seam to lie that extra bit flatter, which it did...
...then I discovered that I hadn't removed the basting stitch and was therefore producing a crease where I didn't want one. Noooo! Just imagine...
Luckily my Jacquard-type fabric did forgive the rough treatment: with a bit more steam I was able to get the fabric to crease where I wanted it to, and the first crease in the wrong place did come one. Phew! Now that's a relief.
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