How things work here

Last updated 18 October 2026.

Who runs this

The guides, calculators, photos and this site are all looked after by me, David. Officially: David Červený, Company ID (IČO) 87013371, Biskupská 3330/10, 702 00 Ostrava, Czechia, registered in the Czech Trade Register. You can write to me at info@cogi.cz.

Guides and calculators are free

I have sewn and tested everything I describe here. The calculator, though, only knows the measurements you give it. Before you cut into expensive fabric, check the printed outline and measure the test square, and if you are unsure, sew a test piece from cheap fabric first. You sew at your own risk, but I am rooting for you.

Printable pattern

Printing the pattern is unlocked with a code you get through Gumroad. Gumroad sells it on my behalf: it handles payment, receipts, taxes and any refunds under its own terms. The code never expires and works for any measurements. It is for you and the people you sew for, so please keep it off the open internet.

What you sew is yours

Sew for yourself, your family and friends. Just please don't sell or share the pattern itself, the PDF, or the texts and photos from here. If you show off what you have made, a mention of whose pattern it was would make my day.

Privacy

This site collects no personal data and uses no tracking cookies. Your chosen language or measurements stay in your browser. If you write to me, I only use your email to reply, and I only put your photo on the site with your permission.

If something is off

Found a mistake in a guide or the calculator? Email me at info@cogi.cz and I will fix it. The same goes for anything else.