Welcome to the final case-making post! This post is very large, because it’s mostly photos.

I went and bought musical instrument foam… a week and a half ago, I think? as planned, but then didn’t get to work on it until this weekend. You specifically want instrument case foam, for its shock-absorption characteristics; it has very little resistance at first, but then much more as additional pressure is applied. There are many kinds of foam, so don’t just grab whatever’s handy! At least, not if you have options.

I also needed but already had foam glue and an electric carving knife, both bought for the zouk case project. Oh, and that’s what you want for foam cutting, by the way: any 60s/70s electric kitchen carving knife. Don’t buy a new one. They’re $3, lightly used, at Any Thrift Store in North America. This rule has never failed me.

Anyway, at this point, you’re pretty much sculpting. You need to cut out the foam around the various protrusions in the case, while also cutting out the shape of your instrument into the applicable layers. To get that correct shape, I put the instrument on the foam and drew an outline of it in sewing chalk. Once that layer was cut, I used that layer as my template guide. This insures your cut-outs line up correctly!

And don’t forget a solid bottom layer, of course. I didn’t really take enough pictures here, really:

The aforementioned bottom layer – 1″ thick

These are to protect items in the storage compartment.

Ideally, you’d buy two foam sheets for this part of the compartment; a bottom solid layer, then a layer you cut into to create a cavity for your instrument. I had to use three layers of foam because the store didn’t stock the right thicknesses; this means I cut the layers, then glued them together with spray foam adhesive.

This picture shows only one of the layers. Note the irregular outer edge; that’s avoiding the previously-described lips and metal corner braces and handle bolts!

The neck support is actually a separate piece, cut out then shaved down to fit with the knife, then glued back into place

Then you start stacking! The white line is sewing chalk. I drew an outline around the actual instrument and used that as a shaving guide. Honestly, you don’t need to be real precise here. Just make sure it all fits together before gluing, and that you got the layers lined up correctly.

Stack Stack Stack

Everything in place!

Note the lid is lined with eggcrate foam. That’s because you want some foam compression but you don’t want hard pressure on your instrument! Eggcrate is perfect for this.

Once it all fits together, including the instrument, take back out all the foam. Put the instrument somewhere safe – like, another room – and the storage compartment foam bricks out of the way as well. Then glue the instrument layers to each other, and down to the bottom of the case. Also glue the eggcrate to the inside of the lid, as you see above. Do NOT glue the edges of the foam to the case! You’ll need mobility there for fabric insertion.

A note about gluing: whatever glue you use will have instructions; follow them. I use spray foam adhesive and lots of newspaper to protect the garage floor, but you have to be able to use that outside (or at least really well ventilated) because damn that shit is flammable!

Just sayin’.

This photo is from before gluing, I just wanted to show a test fit. If you re-test after gluing, make sure the glue is REALLY COMPLETELY DRY first! Then wait another four hours. Seriously.

The final step is to install a lining! You need this not to protect the instrument, really, but to protect the foam from being picked away by all the times you take the instrument in and back out.

For the instrument section, get a thin but strong synthetic fabric off the remnants table at your local fabric store, or left over from an old halloween costume or holiday display. You’ll want something sheer but strong, and slick – the less friction here, the better. Then you literally just moosh it down into the instrument cavity in the foam. No glue, and no precision really needed here – just keep it reasonably smooth and make sure there’s enough that there aren’t gaps between the fabric and the foam of the instrument cavity. The excess fabric around the edges gets tucked in between the foam edge and the case wall. If there’s too much excess, trim down, but be sure you leave enough that it stays tucked in.

For the foam bricks in the storage section, pick any fabric you want. I used a grey stretch fabric from the same remnants table. The rear brick is the more important of the two, because that’s the place things will fall down onto when you pick up the case from flat. (Lift handle, case tilts, everything slides to the bottom pillow. MMmm, comfy!)

Really, these are optional; I’m just paranoid. You can either sew cases, or, if you hate sewing, just glue fabric around the foam, and package it up like wrapping a present. I have a sewing machine, so:

Front pillow (removable)

Back pillow (removable)

None of the cloth is glued down in the instrument section. It’s all held in place by friction, and from experience with the zouk case, that’s all you really need! If you want to take more time to make the instrument side liner more precisely form-fitting, go right ahead – it’s a little bit of a sewing project, and you’ll want to take care with your glue choices, but it’s not anything outlandish. And as far as I can tell, it’s also totally unnecessary.

Note also that the eggcrate is not covered in cloth. That’s also intentional; you don’t want anything to interfere with the compression there, and with a pattern that complex, cloth would make that inevitable. So leave that without a liner!

The storage compartment pillows are intentionally a little too wide, so are held in place by pressure and friction as well. No glue here either, just some really minimal sewing.

Hey look, it fits!


Leave it open for several days with the instrument not in the case, to give the glue time to really cure without exposing your instrument to glue solvents. This is me being paranoid, but I’d rather be paranoid than have solvents affecting my mandolin!

And that’s it! It’s kind of sad that this’ll get the shit beat out of it on the road. If I make another one I’ll add other material to make it less attractive, like, I dunno, a plastic outer layer or something, like on my zouk case. If I had it to do again, I’d also worker harder on weight; it’s lighter than my zouk case, which was my design goal, but it’d be just as strong with plywood sides, and lighter.

But it’s also kind of fitting for such an old instrument to have this kind of case:

Corner detail

Edge detail. I sure hope this copper holds up…

Yay! We’re ready to go on the road!

TALKING OF! I have a show on Friday! 3-5pm, Juanita Beach Market, Kirkland, for Talk Like a Pirate Day (Observed). C’mon out!