I finally got around to documenting the very simple process for coming up with a custom-sized cosy for my mug which I wrote about here. I feel a bit silly putting this up in a way because it's so deadly easy but it actually took me a bit of thinking about the first time around, so in case there's anyone out there whose brain works like mine here we go:
Put the mug in the middle of the paper, nice and straight. For this mug a piece of A4 paper wasn't quite long enough, but once I'd cut it down to the cosy size rather than the whole mug, the narrower shape actually did fit on, just. So if you've got a really huge mug you might need to tape a couple pieces together or use a larger bit of paper. Newspaper would be ideal.
Carefully roll the mug over to one side (I went to the left because it was easier to roll to the right and draw with my right hand at the same time). Don't allow it to wobble or skew, just roll in a smooth arc. If your mug has a handle you'll want to start it from one side of the handle and roll it along to the other side.
Start rolling the mug back to the right, tracing the top and bottom edges as you roll. I traced a bit of the top, then rolled it back and did the bottom and then back to the top and so-on. You can see if you're producing a smooth curve and can realign the mug if you need to. Roll the mug all the way over to the other side of the paper, tracing as you go. When you're done you should have something that looks like this (sorry the pencil line doesn't show so well):
Cut it out along top and bottom curves from the edge of the paper. I folded the pattern in half, matching the ends, and cut it out like that so both sides matched.
Now the step that I forgot to photograph is how you determine how long it should be around your mug. I put the cut pattern on the mug and just pinched the two edges together to get a line that I then cut along. I wanted to have a small gap between the edges so I left it like that, but if you want overlap this is the time to figure that out. In hindsight I should have added maybe .5cm to each edge to compensate for the thickness of the fabric, the gap ended up being a bit wide in the linen version (see below). Obviously if you have a handle on your mug then this gap is where it would go.
I decided that the fabric should be the width of my palm plus thumb, which is about 9cm, so I added 1cm on either side and measured in from the edges of the cup-sized pattern to get the right size. I didn't add seam allowance on the ends, it depends on how much of a gap you want.
Now the bit I have trouble getting my head around is that even though the edge is curved it will look straight on the mug. However, any obvious grain in the fabric will look to be on an angle. You also need to make sure any decorating you do takes this into account.
I made the first one for the red mug in linen with cotton batting sandwiched between and a simple running stitch in red. It's held on with elastic loops and buttons. Love it! It lives in at University on my desk.
For the other mug I thought I'd try a brighter cosy in orange felt. Same pattern but no seam allowances.
Again the running stitch and buttons with elastic loops, and this time you can see how the lines need to be curved but look straight when it's done up. That concept still ties my brain up in knots. I mean, I understand it on the level of that's obviously what you have to do, but any more thinking about how it then translates to straight-looking lines makes my head hurt for some reason. Which is weird because I'm actually pretty good spatially and with maps etc.
This cosy really sticks to the mug - felt and a matt surface work well together! I've used three layers of felt as I only have thin wool-blend felt, and it could almost be reversible with a hot pink on the other side, but the elastic and buttons are for the orange side. I figure it's a bit like sexy underwear - I know the pink's there :) I may add a third button/loop to try and stop that gaping. Or I may not. I can be reckless like that.
Patterns and sewing not for you? How about this one made from a felted sweater sleeve? I might blanket-stitch around the top edge, just to get rid of the raw edge, but otherwise making it couldn't have been quicker or more satisfying - just push the mug down into the sleeve and cut. If you have a handle all you'd need to do is cut a slit and pop the handle through.