Summer days mean cold drinks and cold drinks mean condensation and dripping water. I always use a coaster but in my experience, coasters fall into two problematic categories:

1. Paper based beer mats. These are fun, cheap and easy. But they get soggy on humid days and have to be replaced after each use. Nice for a party but not so good for daily use.

2. Ceramic, glass, plastic or other impermeable material. Look good but result in water dripping all over everything, including your food, book or shirt.

What we need is something absorbent but substantial enough last. Machine washable would be nice too!

Enter the knitted drink coaster.

This exploits one of the usually inconvenient features of wool. When you shrink a wool sweater in a hot wash, the wool fibers do not actually shrink. What they do is curl up and become dense. When you do this on purpose it is called felting. This makes a thick dense fabric that is absorbent but not porous. Wool is naturally anti-bacterial, light weight and shatter-proof. In other words, the perfect material for a drink coaster.

Step 1: Knitting? I Don't Know How to Knit!

Never fear, there are lots of good introductory knitting Instructables. This projects requires the absolute basic knitting experience. In fact, it is a GREAT first project because there are no rules! Make it as big or small as you like, drop stitches, knit one row tighter then the next, run out of yarn before you finish - those are all fine with this project. This is also good for kids because the nice big needles are not sharp and do not require finesse.

Type KNITTING in the search box and you will find everything you need to know. I am not going to recommend just one because everyone has a different learning style and what works best for me, may not work well for you. Read a few and you will start to knit before you know it.

I am an experienced knitter but I make these pretty often. They make great gifts and are also a good way to use up odds and ends of yarn from other projects.

Step 2: Find Some Yarn!

If you have a local yarn store, tell them you want yarn for felting - they will know what you are talking about. If you have to search on your own, make sure you get 100% wool that is not "super wash" or machine washable (means the same thing). Anything with acrylic, nylon or other synthetic fiber that makes up more than a percent or two will not work - it won't felt.

I have not had any luck finding good yarn in hobby or fabric stores - almost everything they carry has a large synthetic component or is super wash.

The good news is that one skein of yarn will make you several coasters, so you can buy the marked down yarn in the discontinued bin. I often mix yarns because I like the look. Stripes are nice (and easy) BUT often turn out misshapen as lots of yarn do not always have the same handling characteristics.

Note: for knitting novices, a skein is the machine formed ball of yarn at the store and a lot is a batch of yarn (there is usually a "lot number" on the yarn label which you should match if you are making a sweater - makes no difference to us here).

A good online source of yarn is Webs - they always have a lot of yarn on sale and they give you enough information to pick the right yarn for your project. You want worsted or bulky weight. Llama and alpaca should work if only a portion of the fiber.

Step 3: Big Needles

You can use needles made of any material you want. You could even make your own using dowels!

I used 8.00mm (US size 11) cheap bamboo double point needles because that is what I had in a nice big size. My needles are 8" long and I did not have any problems with stitches falling off the "other end." But if you do have double point needles and have a problem, just stick something like a bit of cork on the end you will not be using.

The main thing is to have big needles so your knitting is all floppy and full of air. That space is what allows the yarn to squish up when you put it in the washer.

Step 4: Other Stuff You Need

You will need a yarn needle or crochet hook to weave the tail ends into your knitting. Don't buy either one of those for this project though. You can get by with a toothpick or tweezers.

You do need access to a washing machine. Pretty much all of the instructions I have read for felting state a "top loading washer." I have a front loader so that is what I use. It works fine. You can not do this by hand, although felting is not a new art and at some point they must have done it by hand. I do not think modern humans have the patience. I tried it once since I was sure it would work. It did not.

You need a fabric bag of some sort to wash the coasters in. All of the instructions say to use a bag. I have not tried it without a bag, although I frequently wash already-felted coasters with my normal laundry and have no problem. I use an old pillow cover with a zipper. If you have a lingerie bag that would work fine. A pillow case with safety pins to hold it closed will work fine. I am not picky.

You will need something heavy to put on top of the coasters after you wash them. I use books.

So, to summarize the full list:

Yarn

Knitting needles

Yarn needle, crochet hook or toothpick

Bag

Washing machine

Books, bricks or bars of gold

Step 5: Finally, We Do Something - CASTING ON

The first row of stitches you put on your needle is called "casting on." There are a lot of different ways to cast on. There are Instructables on this site and there are YouTube videos. Find the instructions that work best for you.

We are going to use two balls of yarn. They can be different or the same depending on the look you want. Since I use a lot of odds and ends, I usually use two different yarns. The only time this is a problem is when I run out of one kind of yarn before the coaster is finished and I complete the project with a double strand of the other yarn (see blue example below for what happens when you do that!) .

If you want to do the whole thing in one yarn, you can use both ends from the skein you bought but you have to be careful about getting all tangled up. I am not very coordinated, so that may be another reason I use different yarns. You could always make two balls out of the single skein (there are Instructables on making a ball of yarn too!)

In any case, cast on twenty stitches for a generous sized coaster, 17 for a more standard sized one.

It is common for your first row of stitches to feel tight. Don't worry about that, it will loosen right up after a couple of rows.

Step 6: Knit, Knit, Knit

It is a lot easier to knit with two yarns than it sounds. You just treat them like one! Each stitch you take, you push your needle through both loops and you wrap two threads around and then pull the two new threads back to make a stitch on the receiving needle (this prose is why I am not writing an Instructable on the actual knitting method).

The KNIT stitch is the easiest, as you can always see what you are doing. This whole project is done in the knit stitch. This gives nice thickness to the coaster and makes both sides look exactly the same. Just knit back and forth. This does not require any attention, counting or concentration. This is great knitting for a road trip or while watching a movie.

Step 7: Make It Square

Knit until you run out of yarn or until the piece is more-or-less square. You can check that it is square by folding it along the diagonal - the bottom edge and the side should be the same length. It does not have to be perfect or even close. There is no reason that this coaster has to be square. In fact, since the knitting will not shrink the same amount across as it does top-to-bottom, it will not be square when after you wash it anyway. If you REALLY want it to be square, make it a bit longer than it is across - the knitting tends to shrink more in length.

Now you are going to cast off. That is a special stitch which closes all the open loops and allows you to take your piece off the needles. There are lots of different ways to cast off; look in the same places where you found your basic knitting instructions. When you are done you will have a squarish piece with two little tails at the bottom and a loop with two tails at the top. Take the two tails at the top, slip them through the loops and pull snug. Now your knitting is done!

Step 8: Weave in the Tails

To make this piece look as nice as possible, we want to get rid of the tails and the little knots that anchor them. To do that we weave the tails into the knitting. This is A LOT simpler than it sounds.

If you have a yarn needle - or any needle with an eye big enough for yarn, you can simply pull the tail back through an inch or so on the edge of the knitted piece. You can do the same thing with a crochet hook or you can use a toothpick to snag and pull the tail through a few more loops of knitting along the side. This is not science - just anchor the tails in enough so they disappear - the felting will secure them and you will never see them again. Clip off the hanging ends.

Now you should have a squarish piece with no tails. These are nice enough now - you could use them as coasters. But they are big and floppy - not what we are looking for in the perfect coaster.

Step 9: Experiment With Yarn

In one afternoon, I made 4 of these squares, as well as taking all the pictures for this Instructable. I am an experienced knitter, but even a beginner should be able to finish off a couple with no problem. Try different yarns and combinations. I would make one sample piece before you make a whole set, as not all yarn reacts the way you expect. The blue and green one was my favorite before it went in the washer, but turned out to be a disaster (see below) because the two kinds of yarn did not felt the same way.

I like to use variegated yarn - that is, yarn that changes colors. The variegation can be short (as it is in the greenish version) or long (as in the red and blue version). You get completely different effects depending on how long the segments of each color are. One advantage of variegated yarn is that is does not show spills and discoloration as much as a solid color does (that is also why I wear shirts made of patterned fabric).

In the blue and green version, I ran out of the green yarn, so I used two strands of the blue for the last bit - hoping for a stripe of plain blue across the top.

Step 10: Time to Wash

Now you need your fabric bag. Mine is just an old pillow cover that closes with a zipper, but you can use just about anything. A pillow case with safety pins to hold it shut will work just fine. The only requirements are that water can get in and your knitting cannot get out.

I put mine though a HOT wash with a normal load of clothes. Lots of instructions will tell you to wash with a pair of jeans or other rough item, but I don't wash my jeans in hot water, so I just tossed these in with some towels. If you do have a top loading washer, you can take them out before the final spin cycle and you will probably have an easier piece to work with, but my front loader does not let me take stuff out while there is still water in the machine (hmmm . . I wonder why that is?). Mine go through the final spin and are squished up when I take them out.

Lay them out and flatten with your hands. You can pull and prod a bit to get a more even shape, but don't try to stretch them out too much. After the first wash, these were not shrunk enough, so I ran them through with a second load of towels and I was happier with the felting. They will shrink up a little more the first few times you wash them, but not much after the first couple of washes.

Step 11: Felted!

The piece should be much denser now and feel like a very thick piece of felt. You should not be able to make out the individual stitches like you could before you washed it. The two pictures above should give you a good idea of how the texture will change, they are of the same sized section of the piece. The first one is before putting through the washer and the second one, after.

When we felt this piece, all of the little bumps and loops will soften and form more of a solid mass. That is because yarn is actually made up of a whole bunch of individual fibers that are just like hair (sheep hair to be exact). They are not smooth, but rather made up of a series of tiny scales. When we vigorously wash the knitted item, those scales rub against each other and catch, snag and interlock. Hot water encourages the process by opening up the scales and allowing the sharp edges to expand a little. That is what is happening when we felt something.

Machine washable yarn is put through a process to smooth or coat the scales so they do not catch on each other. That is why items made of those yards do not shrink as much in the washing machine. "Super wash" is a patented method of processing yarn that is used by many manufacturers. Those yarns will not felt, although they may shrink a bit if you use hot water by mistake.

Step 12: Poor Misshapen Coaster

I love the colors on this one. Unfortunately, it did not work out so well. This was made with two different kinds of yarn. Obviously the blue did not shrink as much as the green did.

If you like odd shapes, you can us it just as it is. There is nothing functionally wrong with it.

For my tastes, it is too weird. But all is not lost. I will wash it in hot water a few more times to get it as felted as it can be. Then I will take my sewing scissors and cut off the parts that do not look coaster-like. We could never cut into a normal knitted item because the remaining stitches and loops would unravel and make a horrible mess. But because the threads in the yarn interlock when we felt them, there is very little risk of unraveling for a well-felted piece.

Warning: You can only do this after thoroughly felting! If you cut before you wash, the piece will end up as a mass of yarn and fibers.

Step 13: Flatten and Dry

Next, I lay them out on a towel to dry. I put a plastic sheet underneath to keep dampness from seeping to the table (one of those flexible cutting boards) or you could put this on a nonporous surface such as a counter-top.

Fold the rest of the towel over the top and give them a final poke and prod to get them into shape. Then put heavy weights on them. I used books and my laptop, but of course any smooth heavy object(s) will do. I left them overnight.

Step 14: Done and Ready to Use!

The next morning I took off the books and folded back the towel. Voila! Felted coasters!

My favorite is the blue and red stripes. Since I have more yarn like this, I am going to make a full set of these. Perhaps I will give them away but maybe I will keep them. just 'cause I like them This one was made of two strands of the same kind of yarn. Since I did not align the variegation, the colors make a nice stripy pattern.

The coasters can be tossed in the washing machine if they get dirty. I never put them in the bag again and they come out fine. Do not put them in the dryer though, as they will get permanent folds and bumps.

They are pretty much indestructible, don't stick to the bottom of your glass (I hate that) and can be used anywhere.

I'd love to see pictures if you make some yourself.