Building a case

[Mick Bailey]

I've just finished a hurdy gurdy build so the next thing will be fitted case. What materials are people using for instrument cases? There isn't too much information out there. My initial thought is to use 3mm ply or MDF and use glass fibre tape and resin to reinforce the seams, do a double-thickness reinforcing lip for the hardware and then cover it with some really nice NOS Rexine and line it with foam covered in a plush pile fabric. Maybe make up some forms in hardwood and soak some thick leather in water and press some corner protectors like Mesa uses on their amps.

[Leo_Gnardo]

line it with foam covered in a plush pile fabric

I'd be careful about foam, it turns into ick after 20+ years. Might consider felt for padding instead. Many of my customers bought amp slip covers over the last 30 years or so, often the more expensive ones like Tuki and D2F @ US$100 lined with thin foam. The older ones are deteriorating now, leaving horrific lumps of black gack behind. I pointed out to one recent customer slip covers by Studio Slips who use satin quilt lining. Costs a little extra but it's not gonna turn into goo. She got one for her Princeton Reverb and it's the bees knees.

[glebert]

Adam Savage from Mythbusters made kind of a cool guitar case for Eric Idle from Monty Python and did a nice video on it.

https://www.youtube.com/watch?v=6iIZ9rnS6HU

[Mick Bailey]

That's an interesting video just to see his workshop. I need to re-think my space and why I think I've not got enough room.

I was wondering about the foam and was thinking about those foam interlocking tiles used for gym mats but they don't have much give. I don't know whether they eventually crystallize, turn to powder or turn into a sticky mess like regular foam. I had a case from 1927 that was still really nice that had felt padding and a velvet lining (came with a banjo that needed repair) so that could be a choice. I made a seat for my old Harley using layered felt instead of foam and that worked out really nice - still on the bike after 30 years. Some builders wrap up the instrument in plastic and use a can of gap-filling construction foam and let it expand between the case and instrument, but I see this as very short term and maybe give rise to future problems when it breaks down. It also doesn't spring back much when deformed.

[Leo_Gnardo]

I was wondering about the foam and was thinking about those foam interlocking tiles used for gym mats but they don't have much give. I don't know whether they eventually crystallize, turn to powder or turn into a sticky mess like regular foam. I had a case from 1927 that was still really nice that had felt padding and a velvet lining (came with a banjo that needed repair) so that could be a choice. I made a seat for my old Harley using layered felt instead of foam and that worked out really nice - still on the bike after 30 years. Some builders wrap up the instrument in plastic and use a can of gap-filling construction foam and let it expand between the case and instrument, but I see this as very short term and maybe give rise to future problems when it breaks down. It also doesn't spring back much when deformed.

Built to last, or built for near-term expedience? Looks like felt is the winner. I keep a square of felt I got from Stu-Mac, expensive (!) but only use a little snip here and there as necessary, hang the expense, it's lasting me many years. If you can score some felt cheaper from a local fabric store or reupholstery shop so much the better.

As you noted gym mat foam turns into powder after 10 years or so. Urethane spray foam is hard to control to start with, not very compressible, becomes stiffer with age then cracks into chunks when flexed. OK for insulating crevices in buildings, and I find it used as temporary packing for shipping speakers from certain manufacturers.

Time was, maybe 100 years ago more or less, felt was the go-to pad material especially in the UK where woolen goods were in widespread use and a major industry. Cloth, carpets, even packing material for fragile items like glassware, light bulbs & ... vacuum tubes. Felt mostly made from scraps was a standard padding material and as you found in your Harley seat can last more or less indefinitely, as long as it's kept dry and not attacked by rodents. Foams became the modern substitute as the petroleum industry matured and found new uses for its byproducts. Some things do stand the test of time. What is it the old folks say over there? Horses for courses, I think that's it. Or is it courses for horses... either way 'round I think it's appropriate.

[Mick Bailey]

The Harley seat was an experiment. I wanted something firm but not squishy and cover it with thick leather. It needed to be firm so the leather wouldn't bag and go slack. I went to the foam stockist and saw the felt by accident when I discovered they had nothing I wanted in the foam line. It was on a roll and about 12mm thick so was easy to build up and shape. I never though about it lasting or not, but durability is something only seen in hindsight so I couldn't have planned it better. So maybe a rigid case lined with felt and padded with velvet. After running through ideas in my mind with all kinds of quick and easy routes to success/failure, I'm back to that 1927 banjo case with design and materials. It sure would smell nicer than foam in years to come.

[Leo_Gnardo]

T I'm back to that 1927 banjo case with design and materials. It sure would smell nicer than foam in years to come.

Roger that! And if you can find some of that leather dressing that makes old English sports cars smell so good, so much the better. If you do, let me know where I can score some. I want to use it for after shave....

[Mick Bailey]

That's exactly what I used on the seat as well as the leather seats in my little Bertone sports car at the time. It's called Preslea, but don't go looking for it nowadays. It used to be really good and give that really nice smell and was rich and nourishing but not sticky. They changed it and it's now thin and watery and doesn't smell anything like it used to. It's on my after shave list of smells, too.

[Leo_Gnardo]

That's exactly what I used on the seat as well as the leather seats in my little Bertone sports car at the time. It's called Preslea, but don't go looking for it nowadays. It used to be really good and give that really nice smell and was rich and nourishing but not sticky. They changed it and it's now thin and watery and doesn't smell anything like it used to. It's on my after shave list of smells, too.

Drat. Someone oughta figure out what Preslea was and offer after shave / cologne with that scent. I expect it would be the secret weapon. As for the current offering, why why why can't they leave a successful product alone. Phooey!

[LastHours12]

Those interlocking gym mat tiles you mentioned are made of closed cell foam. As far as I know, it can also be used to make case inserts. Closed cell foam is polyethylene-based as opposed to the more common stuff which is polyurethane-based. I'm not 100% sure about the differences over time, but I suspect it would hold up better.