Marathon Guitar Case Build.

[DarwinStrings]

For the moment I am pretty stuck on the parlour sized guitars I am making, good for me to be enthusiastic but because I make them a bit deep I can't get a case for them. I can but it is a dready case and is a bit big so I decided (cause I am a sucker for punishment) to DIY. I looked at wood but could not find lower grade veneer only face stuff and it ain't real cheap.

Fibreglass, Christ! Messy stinky itchy stuff and it ain't much fun to suit up in the tropics. I also had a look at ABS but needed a heater and a vacuum pump that I don't have so decided fibreglass was bet suited to the gear I have at hand.

So I have finally finished the molds and have been advised to give them a month to rest before using them, this is because I used a tooling gelcoat rather than just the finish gelcoat, seems I could have used either but the tooling stuff was only $20 more.

Here is where I am up to so far.

I had to make a top and bottom so I shaped the leading edges of both plugs together so it will mate in the end.

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Building up the MDF plug

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Rough plug shaped

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I used black so I could see and bad bits of shape then filleted till the black looked okay.

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Then painted them white so I could see the blue PVA bond break going on. It is water thin stuff to spray so I wanted to see it clearly to avoid runs.

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PVA spray on the plug

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I tossed up between doing the right thing and buying a gelcoat gun and hand brushing. In the end I went El Cheapo and brushed the stuff on which is a bit tricky but it worked in the end.

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That is the glass finished with bracing applied to keep the mold as rigid as possible

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The two molds finished in Ferrari red tooling gelcoat

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[J.F. Custom]

Awesome.

Nothing like going that extra mile...

Jeremy.

[simso]

Holy shit, thats really neat

[kiwigeo]

Mafia approved??

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[DarwinStrings]

Cheers guys. Can I borrow your CNC next time Steve.

While I think of it I will add that I particularly wanted something I feel comfy enough leaving in the hands of the baggage handlers at airports. Around town I just use what ever case I have empty and that does for that. My best bet was looking like Presto Cases in Perth but they only go as small as a classical case and that is still a bit bigger than I need.

It would have been roughly $1200 for the two cases I really need from Presto and in the end I should be able to build the first two cases for that or less (plus a load of labour) that includes the plugs and molds and the first two, any I make after that get cheaper, if.

Seals?....where do you get that stuff? Turns out this is almost an impossible task but I lucked out with a favour from Gary Price of Price Cases which is enough for two or three cases. After that I might have to work out something a bit more generic than having to pay for dies and buying a thousand metres per run.

[ozwood]

I am truly Impressed Jim,

Having been through the same process making various parts for boats, I really appreciate the effort that went into that.

Are you taking orders

Cheers,

[DarwinStrings]

Cheers Paul and as for "taking orders" I guess if someone here wanted one for a parlour my arm could be twisted. Maybe twisted into a finished case or maybe just the unfitted shell or (what might be best for me) freighting you the molds so you can knock up a few shells yourself then return the molds. So you can see I have given it a though but about the only decision I have made is that I have no intention of competing with Hoffee.

[johnparchem]

Pretty amazing work to build the mold. I will be interested to see the pictures of the layup for the cases.

[DarwinStrings]

Me too John



Edit...Oh do you mean glass layup. Have not quite worked it out yet but working of vague layup weights I might go three layers of 300g/m^2 chopped and one either side of that with a weave and I guesstimate about 4Kg in that then add hardware and lining to get around 6Kg ish. There is quite a bit to think about and I am a novice with glass.

[demonx]

Looking good!

I hope you update this thread as I'm keen to see the finished product.

[DarwinStrings]

G'day ANZLFers. Finally got around to using those moulds I spent all that time on, bad decision. Bad decision in the middle of the 'build up to start fibreglassing, what a shit fight. Almost done though just need some feet and a handle. I went okay but its a bit rough, good enough for me but will do a few different things next time.

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Jim Schofield

[kiwigeo]

I reckon that case looks pretty flash Jim. Nice work.

[Bob Connor]

Top notch Jim. Very impressed.

Regards

[ozziebluesman]

That's a great looking case Jim.
Very professional!
Cheers
Al

[blackalex1952]

Nice work! Hope they don't weigh too much! I have some opinions to here. Cases should not be black, particularly in Australian climate.The reason is that many people unconsciously leave guitar cases in windows, cars,etc. Black cases are heat banks, white reflects heat.A case left in a window or in the shade can end in full sun later in the day. I have seen and repaired many instruments that have suffered heat and humidity damage this way.One example was a high cost Lowden which was purchased with a Hiscox case. The liner of the case was polystyrene foam moulded into the case with synthetic felt of some sort on the inside.In the centre of the back the polystyrene had not bonded well with the plastic of the case but was well bonded around the sides, resulting in an air cavity, which when heated in the sun or near a fire in winter or whatever, expanded and seriously deformed the back in a concave, both deforming and splitting back braces as well. The back became permanently concave from its normal (estimated) 15 ft raduis to a concave that was 8mm deep when a straight edge was placed across. The concave was in the centre of the back only.The foam inside the case was also permanently concave, so in effect the instrument was being placed in a press everytime the case was closed, and going through regular heat and humidity cycles as the guitar was moved from location to location.

[johnparchem]

The case looks great. It was great following the process.

[peter.coombe]

Nice looking case, well done. I would agree that cases should not be black. I did a test on some mandolin cases a few years ago. Average air temperature was 28deg, internal temperature of black case went up to 51deg! White case went up to 37deg. That was after only 1/2h in the sun.

[DarwinStrings]

A mate told me I should not have made it white cause it will show dirt and marks but I'd rather have it a bit grotty and cool. Also to me it is the case that takes all the grot and bumps to protect the instrument and a case just looks better if it has a few miles on it, that's what it's there for.

I guess how much it weighs was not a big concern for me Ross as it is supposed to be a flight case and my main concern is protection against baggage handlers that are having a bad day at work. I will weigh it when it is finished to see how I went as my aim was to be less than 6 Kg.

Thanks all for the remarks and to be honest Allan it is not so pro up close as I had a bit of wax trouble with the PU paint also I will be able to do a much better upholstery job on the second as the experience with the first helps.

Jim

[slowlearner]

That's a great looking case. Good call on the white paint too.

What is it with every slicker round here that they want to drive a black car in Australia?

[DarwinStrings]

So I just weighed it Ross and once I add a handle and feet it will come in a handful of grams over 5Kg so I am very happy with the toughness to weight ratio.

Yep Pete people drive black cars up here too so either they suffer for their style or they always leave the car and its aircon running when they park in the sun.

[routout]

Wow the fiberglass mould on it's own is great now you can pop em out by the hundreds when people ask me to make something in fiberglass they always assume it's so cheap to buy ,I can appreciate the effort and time you have put in there Congratulations.

[blackalex1952]

Next project--CF cases....?I made a vacuum system for around $150 after a lucky score on ebay of a vacuum pump, brand new. It was left over from a large laboratory that closed down. But an ebay alert will turn up items that one is seeking...I just visualised a bargain and there it was. The pressure cylinder is from a burnt out el cheapo compressor from the local tip, along with a distributor diaphragm from an old holden. The diaphragm is balanced by a spring and a wing nut -this activates a Jaycar microswitch. The purchases were non return valve, vacuum guage, brass fittings.The rest was lying around the shed.Works fine.I use it for veneering backs and sides and bridge glueing etc. But down the track I want to try working with some CF-budget and other projects permitting...The most important issue is to make sure the vacuum bagging used doesn't leak so that the pump doesn't cycle continuously during long glue/resin hardening times. That causes overheating and risks damaging the pump.

[blackalex1952]

I am interested in what you made the seals for your case from, and how you mounted them? Did you form a moulded channel for the seals to sit in?

[DarwinStrings]

Just looking back over the thread John P. I caught something you said about the layup. I used four layers. First a layer of 10oz/m² or 280gm woven mat then two layers of 300gm/m² chopped mat then one more 280gm woven. I could add another layer of chopped which makes it tougher but adds more weight so I am quite happy with the four layers but I know some of the commercial makers use more layers. I also added a couple of braces across the body, front and back out of 5mm WRC covered in glass

No plans for using CF Ross at all as the glass seems to do the job. I was going to use some CF as reo in a few places but thought I would try just glass for the first one and am happy with the over all toughness, I reckon if you dropped it out of a plane then there is every chance the glass would break and that may even help protect the guitar but I hope I never find out.

I have certainly considered bagging it and vacuuming as that seems like a lot less mess and sweaty itch but for now will just wait till the cool of the dry season and try again with the brush.

The seals are rubber extruded with a sort of step that keys on the mating surfaces and U shaped to fit the glass edge (which I thickened with a few more layers). I just glued it on with CA which was the advice from the guy I got it from. I could not find anything available that was a purpose made seal so just tried the guys who make these types of cases and got lucky to get enough for a few case from Gary Price in the USA.

[kiwigeo]

I'd like one of those babies in crocodile skin