Fin Cover/ Board Cleaner/ Potholder?

A friend of mine recently showed me her solution to protecting her fin in the car from the other boards: a glove potholder. While I certainly can appreciate the ingenuity and reuse of something from around the house, it didn't fit so well because the glove was far too narrow and straight to rest completely over the fin.
I gave her a fin cover, but those type are really for storage use, not everyday wear and tear. For this use, I needed to make her something extra padded and soft so it wouldn't scratch her other boards.
I was in Tar-Jay yesterday when I came across some drying mats. These mats have a thick foam core layered between sheets of terrycloth material. What better material to use for this project?

2 drying mats, 18" by 15" each

Next, I wanted to make it in a fin shape without being too exact in case it needed to be used on other fins. I used a 9" large SUP fin as a model:

9" SUP fin

I used some butcher paper to draw a pattern out around the model fin that was at least 1/2" bigger all around, even more so at the top of the fin to accomodate up to 10" fins, plus the seam allowance.

Sketching the pattern

After cutting my pattern out, I laid it on one of the mats and flattened it down with my homemade pattern weights (canvas pillows of BB shot) for cutting, aligning the bottom edge with one of the finished side hems of the mat. This saves me from having to finish that edge:

Getting ready to cut out the shape

The core of the mat

After cutting one out of each mat, the tricky part now is sewing them together.
I stapled the two pieces together instead of using pins so the edges wouldn't distort:

Don't forget to remove your staples or the cover won't do it's job!

The overall thickness of the two mats together is 5/8". I wanted to overlock the edges to flatten them down a bit to make it a bit easier to sew. I don't have a serger, so I used an overlock foot and set my machine to the highest width possible on a straight overlock, 7.0, and a length of 2.5. If you are hand sewing this, which is certainly doable, use a blanket stitch in a comfortable spread.

Used a sharp needle for synthetics, at 90/14 since it was thick.

Sewing the thick pile!

Overlocking of the curved edges finished-
 didn't need to do the bottom, it was already finished.

Although the cover could work like that, since the overlock stitch will prevent any fray out of the edges, I wanted that potholder feel, so I went with some bias tape edging, double fold extra wide:

Don't ask me why the lady is holding her neck in the picture-
maybe the company wants to cash in on the whole vampire craze too.

I clipped the end at an angle first:

Then, I folded the pointed part inwards, to be sandwiched around the side seam:

Remember that the bias tape always has one side wider than the other- put the wider edge on bottom, narrower on top. This ensures you catch the tape underneath when you sew.
Here's the cover completed with the tape edge over the raw edge seam:

The useful thing about this cover is not only is it thick enough to endure some hits, the cover can be used instead of a towel so she could use this to wipe down her board before putting it in the car. This cover fits up to a 10" fin of that general style (a big hatchet fin need not apply).
Yes, it can also be used as a potholder.
ShamWOW!