Intro: Diaper Flask
The pro tip that I'm demonstrating is cove cutting on the table saw. Find it in step 3.
I have a two year old. When I take him out I only want the bare essentials. Normally, I just place a few wipes in a zip-lock bag, fold a diaper in half, and shove it in my back pocket. The problem is, they eventually wiggle out and disappear. This setup also keeps things together when I put it in my car door.
It's a flask shaped wallet that compresses a diaper and wipes. It also keeps them from slipping out of my pocket. It has a curved inner shell I hammer formed over a piece of hardwood oak. The outer lining is leather while the inner is denim.
Step 1: Prototype
I cut a couple rough rectangles from 22 gauge sheet metal. After shaping them by hand, I used duct tape for the hinge and closure. Everything seemed to work well but I did learn I had to make the rectangles a little bigger.
Step 2: Glue Up the Form
I picked up a piece of 3/4" oak from the hardware store. It cost just over $11.00. I cross cut it on my table saw and glued one piece on top of the other. Make sure to spread the glue out evenly. I used a plastic squeegee.
After that I clamped them together and let it dry.
Step 3: Cove Cutting
Typically, a table saw set up for cove cutting includes approaching the blade at an angle. This particular setup is perpendicular to the blade. Going across the blade at ninety degrees will provide the widest arc you can cut. If you were to use a steep angle like 10 degrees, you'd end up with a parabolic shaped cut.
Start out by making sure your saw is off and unplugged. Next, raise the blade so you can center your piece of wood on it. This will help you visualize where the final cut will be. Once you have the right placement, you can clamp your guide into place. I'm using a section of metal bar stock. Keep everything nice and square by measuring the placement of your guide against the back edge of the table saw. Make sure the clamps don't interfere with the path of the wood. Lower the blade back down to zero.
Let's get cutting. I recommend using push sticks. With every pass you'll raise the blade 1/4 turn. This will remove about 1/16" of material every time. Make sure you keep constant even pressure both against the guide and table. If not, the blade will try and push the wood toward you; ruining your cut. Every time you raise the blade, more and more material will be removed per pass. This means the rate in which you feed in will slow down.
Once you have the depth you want, you can use sand paper to remove any cutting marks.
Step 4: Completing the Form.
I cut the shape to size by comparing it to a diaper. Next I clamped it down and began to cut in the top curve with a block plane. I used a sanding belt to finish off the curve.
To round over the edges I used a 3/8" roundover bit in my router. Finally I sanded it down with 220 sand paper.
Step 5: Cut the Shell Blanks to Size.
Before I cut any metal I used a sheet of paper as a template. Using paper makes it easy to see how much extra you need to add to accommodate for a curved edge.
Next I used a file to mark the cut line. After cutting the metal with shears I filed off any sharp edges.
Step 6: Setting the Form.
In order for the metal to take shape when you hammer it, it has to stay in place. Otherwise, the force you put in with each blow will dissipate with the movement. Gorilla brand duct tape worked well here.
You can't do the entire shell all at once. You have to tape it down and work a couple edges at a time.
Step 7: Hammer Time.
I started with the front and back edges. Then I added more tape and hammered the sides.
The corners are the tricky part. As you hammer in from one side, the other side will pop back up. Just keep going back and forth and it will take shape. Again, make sure the form is not sliding around.
I did this for both the top and bottom shells.
Step 8: Glue Up.
I scuffed up the shells so they'd adhere better.
I cut out a piece of 5/6 oz. leather. Keep in mind how much extra is needed to account for the curved edge and the hinge area.
I sprayed both pieces with contact adhesive and let it become tacky. Once I laid the shells in place, I smoothed out the leather.
Step 9: Trimming the Excess.
I rolled the leather over the edge and pushed it down with a metal rod. Having the leather pushed down like this helped keep it all in place as I cut. Using a razor blade, I used the metal edge of the shell as a guide to trim off the excess.
I painted the edge black with oil based paint. This made it look more finished.
Step 10: Lining the Inside.
Doing the inside was a lot like doing the outside.
I cut out a piece of denim and sprayed both pieces with contact adhesive. After it became became tacky, I laid the material in place and smoothed it out.
I used a razor to cut off the excess.
Step 11: Add the Closure.
I made the closure out of the male side of a snap grommet and paracord. I passed the cord through a hole and burned the strands together. This created a little paracord bead that won't pull back through the hole. A bur was left behind from the hole I drilled. This turned out to be a plus since I can adjust the loop and the bur keeps it from slipping.
Thanks for checking out my project.
Second Prize in the