Rotary cutter and patchwork ruler: for sewing bras, among other things

Dear users, dear authors,
what are rotary cutters and patchwork rulers?
I found this here in the product description:

Hexagon Patchwork Doily

If you want to do patchwork well and correctly, a patchwork ruler and a rotary cutter are indispensable tools. I have a good selection myself because I did a lot of patchwork for a while.
As for rotary cutters, I have one with a 45mm blade, one with a 28mm blade, and a circle cutter. As for rulers, I have a 60 cm x 15 cm, a 10 cm x 45 cm, a 15 cm x 30 cm, a 10 cm x 10 cm, plus two rulers with inch markings, and a 9° ruler. >I needed the 9° ruler, for example, for projects like these: the wall hanging, the bag, and the coaster are all made using the 9° ruler
The circle cutter is used when you need a circular piece for whatever purpose.

Best regards, Inge

Great pictures
Thanks for the info

The small rotary cutter is also ideal if you sew your own bras and other lingerie, because the smaller blade glides around every curve much more easily than the large rotary cutter. On top of that, when you cut lingerie with scissors, you always have to lift the fabric slightly because you need to get the blade under the layer of fabric; with a rotary cutter, the fabric stays in place and doesn’t shift or stretch. This is especially important when sewing bras, because the cups need to fit well and sit properly.

Best regards, Inge

Okay, good to know.
Not that I would ever have thought of sewing underwear myself, but still.

Could you reply over in the thread:
Sewing the bra underwire back in (No advertising)
That would be great.

Dear Josefa, I feel the same way you do. It would never have occurred to me that you could actually sew bras on your home sewing machine. But I think Inge is the only one here who can do that. She’s our sewing pro, after all! Everyone else is already happy if their regular homemade clothes turn out halfway decent and are wearable.

Best regards, Ina

You can’t—and don’t have to—know how to do everything. 

Josefa is right—you don’t have to be able to do everything. For example, I can’t sew wedding dresses; I wouldn’t dare try. That’s my daughter’s domain—she learned it in a craft class, and she’s the one with the fine motor skills in our family :-) I’m the one with the gross motor skills :-);-)
But my daughter and I took a special class just to learn how to sew bras.

Best regards, Inge

How much fabric do you end up cutting away or wasting before you become really good at this as a seamstress?

It all depends on how distracted you are when tackling something like this. As always, it’s important to get yourself measured properly beforehand and then choose a pattern based on those measurements, because if you go by your usual store size, you’re guaranteed to fail the first time—that’s exactly what happened to me. The bra was way too big when I finished it, so I had to start all over again, but then it fit perfectly :-)
 I see this as learning by doing :-)

Best regards, Inge

Especially with challenging patterns, you should sew a test piece first to avoid getting frustrated later. This can be particularly useful when sewing clothing, since you may still need to make pattern adjustments.

I haven’t sewn a bra yet either ;).

Best regards,
Sonja