Waterproof Swimming Bag

Sprat has started swimming lessons.  I felt rather sorry for him today as he was the only child in his group dragging his swimming gear behind him in a plastic supermarket bag.  So having a rummage around in my treasure cove of sewing materials found a big piece of waterproof PUL and a square of thick Thomas the Tank Engine material (that was originally brought out of the clearance bin, destined to become the covering on Danger Mouses headboard - sorry buddy).  Everything I need for a swimming bag right.  No, missing a pattern.  Bah, who needs a pattern. 

I had a picture in my mind of what I wanted, figured it would be easy to whip up from scratch, and it was.  Here is what I did.

I wanted a nice round base - so used a plate - perfect.

I then had to work out how much material I needed for the bag (to go around the base).  I don't even know what this is called.  I took cabbage maths at school, so this was a tricky one for me.  Thank you Google for saving me.  You can google this too, as I am definately not qualified to re-explain this.  If I can work it out, anyone can.  Remember to add your seam allowance onto this (as you can see below my width was 80.1cm plus the seam allowance).

I used the two seperate fabrics - the waterproof lining and the thick TTE outer.  I placed the two fabrics together and cut out the base, and then the bag itself.  When I looked at the length I had allowed for the bag (49cms) I decided it wasn't enough, so just cut some extra at the top, as you can see in the below photo.

Once the bag was cut out, I seperated the two pieces, pinned and sewed each piece down the side seam (creating a tube), and trimmed the excess hem.

Then I pinned the base to the bag, right sides facing together, and sewed the base on.  I did this seperately for both fabrics, then again trimmed the excess hem.

I then turned the outside of the bag right side out, and popped the lining inside this.

I wanted a drawstring close on the bag, so I added two button holes to what would become the top hem, for the drawstring to go into.  I measured out where I needed these to go, allowing enough of a gap between the button hole and the top of the fabric for the hem to be turned in 5mm and then turned down again another 4cm.  My button holes are on the inside of the bag.  You can see them (not clearly sorry) on the next photo, on the right hand side.

I then folded the top hem (in 5mm, and then again 4cm), leaving plenty of room for the cord, and sewed shut. 

Then I realised that I had no cord (this was not a very organised project).  So for now I am using ribbon until I get to Spotlight.  Next time I made one of these, I am going to add in a loop on the outside of the bottom of the bag, so the drawstring can go through the hem, and be looped down and knotted through the loop at the bottom, meaning the bag can be slung over a shoulder.  Next time.  But for now, I threaded the ribbon through, and there you have it, a swimming bag.  No more plastic bags for Sprat!