Heyas I`m back again. This time I figured I wouldn`t put "Steampunk" in the title, although this project is probably as steampunk as I ever got...
Anyways I want to show you how I built a dock / acoustic amplifier for my new smartphone. I got a Sony Ericsson Xperia X10 mini pro, but with a couple of changes in the design I`m sure you could make one that fits your phone.
I used copper sheet & pipe because its what was available at my local hardware store. For the horn part I`d like to have used the head of a copper watering can - or an old brass car horn - but in the end I had to settle for a plastic watering can. I`d have preferred to use brass but couldn`t find any. Other things you`ll need are a drill, a metal jigsaw or a rotary tool with cutting attachments, a set of small files, different grits of sandpaper (220 - 1000), epoxy or some other strong glue and some kind of felt to line the inside so your phone won` t get scrached...
The reason I kind of rushed the completion of this instructable is that I wanted to be able to enter the new Epilog laser cutter challenge, so If you see the I`ble, check out if they`re still voting over on the contest site ;-)
As to what I would do with a laser cutter, I can`t even begin to count the possibilities... But my brother and me have been talking about setting up a makerspace in our town, and I guess the laser cutter would be the perfect tool to attract new people...
I got inspired to do this little project by the excellent Gramophone mp3 player as seen on http://brassgoggles.co.uk/forum/index.php?topic=3490.0 as well as the Bone Horn Stand for the iPhone http://www.ubergizmo.com/2010/10/gramophone-amplifier-for-your-iphone/
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Step 1: Plans
First you have to measure the dimensions of your phone. This was tricky with my phone because the screen was the only really straight surface - so I had to eyeball a lot of the measurements. To make sure I got them right, I made a quick blueprint on a piece of paper, cut it out, folded it as planned and checked if the phone fit into it nicely.
If this works out, you may proceed to transfer your plans to the sheet metal of your choice.
Once you cut out your basic shape use a file or some sandpaper to clean away the burrs left by the cutting.
After this, use extra care to measure and transfer the corner points of your phone`s screen and important buttons to the sheet. (You can also use a centerpunch to transfer them from your plans, if those are exact enough for your needs - it`s what I ended up doing). You can already drill some pilot holes in the corners at that point and use them to check the alignment with your screen.
Step 2: Folding
Now it`s time to give this sheet some shape! I used the vise on my woodworking bench to hold the sheet while I used my hands to bend it to about 85 degrees, then whacked it down with a rubber mallet until it was a nice 90. If you have a sheet metal bending tool, by all means, use it!
If you just want to fold a single box like for an iPhone or similar device, this step is easy enough: just repeat what you did to your paper plan to make it fit around the phone.
If your phone, like mine, has a slide-out keyboard you might want to copy my design. In that case you`ll have to think the whole bending process through: which bends to make when so you can still use the vise afterwards to make the next bend. It can be kinda tricky - but I`m confident you`ll figure it out.
You should end up with something that you can (carefully! You don`t want to scratch it!) slide your phone into to see how it looks. Re-check the alignment of your screen through the pilot holes and make sure the phone does not slide around in the case. You`ll be adding the felt lining later, so a bit of play is no problem. If anything doesn`t fit , see if you can adjust the case by bending it in shape, cutting away excess material or covering it up with decorations later.
Sorry about the lone pic - it`s the only one that came out semi-presentable... the others were all blurry.
Step 3: Cutting
Now it is time to bring out your trusted rotary tool. Mark the position of the screens edges on the sheet (if your positioning has proven to be off in the last check you can try to correct it now).
Use clamps to fix the back of your box to your workbench, mount your hearing- and eye protection (really, guys, this time they`re worth it!) and start grinding away! This step took a lot longer than I expected it to - but then again, not really being used to power tools, I tend to overestimate them. I planned to use a jigsaw to do this step at first and you still can, if you want to - but you`ll have to do it before the bending part...
Anyways after this, you`re almost done! Use your files to clean the edges of the holes you cut, then clean all surfaces with sandpaper. I started with 220 grit and steadily worked my way up to 1000, then I used the buffing wheel on my rotary tool to finish it off with some polishing paste.
Step 4: Building the Horn
I used a hacksaw to cut the copper pipes to length (btw. not the way to go - use a pipe cutter if you have one) I just needed two pieces, one about 6cm long and another about 2cm. The elbows were a nice fit and I didn`t see the need to solder or glue them together - after all I wanted to be able to adjust the orientation of the horn.
The back of my case ended up with a slight curving to it because that`s the shape of my phone, so I had to grind the end of the 2cm bit of pipe to the same curvature to make sure I have a nice contact surface for the epoxy. I simply put a bit of 220 grit sandpaper between the pipe and the back of the case and gave it a couple of strokes - perfect! Then I used epoxy to glue it in place over the hole I drilled (I waited with drilling this crucial hole because I still wasn`t sure how I wanted to design and attach the horn while I was building the case). Thankfully my guesstimates turned out to produce a neatly aligned loudspeaker.
After that I had to find something to give it the classic gramophone-horn shape that would fit over the elbow. My girlfriend had a good eye for size when she pointed out the sprinkler head as an option. We were checking the hardware store for anything good to re-purpose as a miniature gramophone horn and she picked it up - it was just a couple of cents so I bought it without even measuring the diameter. Turns out it had the exact diameter of the elbow - nice!
I admit that I would have preferred a copper sprinkler to a plastic one - but buying a new copper watering can for 50 bucks just to cut off the sprinkler seemed a bit drastic to me... maybe I`ll find something at a yard sale later - I`ll get rid of this thing as soon as possible. Be that as it may, it being made of plastic made me drop the notions of soldering the pipes together and, once again led me down the aesthetically dubious but enticingly quick and easy path of strong glues.
I spraypainted the sprinkler with copper paint, which came out surprisingly convincing. I still don`t like it and it`ll have to go as soon as I find an alternative.
Step 5: Protective Coating
I gave the finished body a couple of coats of clear acrylic spraypaint as a protective coating - especially since I have extremely acidic sweat ("stainless" steel my ass!) and I don`t really like the smell of copper. I considered aging the surface at first - if I recall correctly sealing it in a container with some ammonia overnight would have given a nice result - but I decided against it after having spent so much time removing toolmarks and polishing the thing...
I only coated the body without the horn attached because I wanted to be able to adjust the angle of the horn - had I left the whole assembly attached the paint would have ended up glueing everything in place...
Note: The pics below are from the first coat I applied - as you may notice I hadn`t drilled the hole for the loudspeaker or attached the short piece of pipe as a mount - I realized after taking these pictures that I would have to remove the paint with sandpaper where I wanted to attach the mount - I would have to do it all over again! *facepalm*
Step 6: Lining
To make the felt lining, use your paper template to cut the felt in shape. After that, it`s back to our old friend, glue. I used a water-based multi-purpose glue to glue in the felt lining - up to now it did the job. I used pointy nail scissors to cut out the holes after the glue had cured. You can of course try to cut the holes first, make sure the fit is perfect, and then have a wrestle with the thing to get it in before the glue starts to cure - be my guest.
After that, you just have to assemble the horn, slide in your phone, turn up the volume and enjoy the music.
I did initially plan to make a base for it with the usb cable already in place so you just have to slide in your phone and it`ll automatically start to charge but when I noticed how nice the angle looked with just the horn acting as a stand I decided to leave it at that...
Participated in the
3rd Epilog Challenge