This Instructable is mainly about making a plexiglass control panel for the Weird Sound Generator.
One of the benefits of having a plexiglass control panel is that you can see the guts of the unit from the outside. If you don't think that is cool, you get tired of it, or you want something more professional you can easily whip something up on the computer and print it out on photo paper. The plexiglass over the printed paper can actually look extremely nice especially if you are an accomplished graphic designer. You will have to put the paper on at the very last assembly because I doubt it would survive the entire construction process. Another benefit is that if you come up with a different design or the red begins to fade because you left it out in the sun I suppose you could change it out in the future.
The components are not properly grounded if they are fastened directly to the plastic surface. This could result in the infamous 60 Hz hum that plagues many audio projects. To overcome that you have to come up with a creative way to interconnect the components with a conductive material which I will go into more detail later in this instructable. Another downside is that plexiglass can get all smudged up and look grimy. But you can always clean it up again. If you have a printed graphic on the other side of the glass you have to be careful not to get any moisture beneath the plexiglass. A metal pre-etched panel would be more ideal and you can purchase them pre made with the holes pre cut.
Before you actually do anything please read through everything and do your research. You will have a better chance of having positive results! Otherwise the probability of catastrophe increases exponentially with your greater ignorance ;-P
About this Instructable:
When I set out to do any project I almost always document my work with lots of photos. I thought I'd share some of my adventures from my journey building a Weird Sound Generator similar to what is found at the http://www.musicfromouterspace.com website. There they have everything you need to know about building this on the WSG project pages. Be sure to read through all the information there to determine if you will be able to come up with what is needed to complete the project. To make it simple for you they have pre-drilled and printed face plates, pre-printed circuit boards, and even occasionally they will offer complete kits. And if you don't want to build anything yourself I suppose you could buy a fully constructed unit for a handsome chuck of change in comparison to what it costs to DIY (do it yourself).
My only cost up front was for the PC board bought at MFOS and the electronic components purchased from Tayda Electronics. The plexiglass for the faceplate and the wood for the cabinet I had laying around from other projects. Of course all the tools I needed I have collected over the years. All together including shipping I spent $23 on the PC board and a about $20 on electronic components part of that was because I made a later order to replace a part I broke and decided to add some other parts to slightly mod the final unit with some cool LEDs. Also instead of battery power I am using an old 9 volt power supply I had leftover from something else so I needed to purchase a power jack.
This project requires a basic understanding of electronics and reading schematics, basic equipment and soldering skills, and possibly the tools and ability to build and assemble your own cabinet. It is interesting to see examples of what other housing people have used for this project everything from lunch boxes to model skulls and toys.
Step 1: Get Your Parts
Choose what parts you need:
Go over to the Music From Outer Space site and go over to the Weird Sound Generator section. Study everything it takes to build the WSG and what things you might add to make it in your own style. Since they had a PC board for only about $15 I ordered one from their site. That made things much easier than figuring out how to design my own. If you feeling ambitious and are really good with a schematic then by all means put together your own. You can order a blank proto-board on most electronic parts sites.
For the components look for the tab that says "parts list". Then you either buy their kit or scout for parts online. When buying parts many stores sell the smaller components by minimum quantity. If you do a lot of electronics kits it is one way to build up your supplies. I have set up an inventory on my mac so I can keep track of what parts I still need to order for new projects. I found a program for my Mac called zParts and downloaded it from sourceforge.net
I ordered my parts from http://www.taydaelectronics.com for a pretty decent price. Other times I've ordered parts from https://www.sparkfun.com
Make sure you order IC Socket Adaptors for the Integrated Circuits rather than soldering them right to the board. If something goes wrong it will be much easier to replace them. The Socket Adaptors are not on the parts list. Make sure you get the audio output type that you prefer as well. Also I ordered a power jack because I wanted to use an old 9 volt power source I had laying around. There are some mods for adding LEDs so I order some extra LEDs and holders to mount them to my control panel.
Inventory your parts:
When your parts arrive check to make sure you order is complete and that you have everything you expected. Be careful with the IC chips as they are susceptible to damage by static electricity. Keep them in their anti-static packaging until you are ready to install them. I have several storage boxes I store my components in and the components are individually packaged and well marked so I can identify them quickly when I need them.
Step 2: Control Panel Layout
Plan the layout of your control panel:
You may have a rough idea how the panel should look and perhaps you will simply go with the layout on the WSG project site. That would be the safest least confusing thing to do for the layout of the control panel. If you do change the layout, be sure you are certain where everything will be so you can adjust your wiring accordingly. It may help to draw a diagram.
I slightly adjusted the layout of my control panel so that the switches for the Voice A and Voice B would be in two separate rows instead of one row across the middle. This potentially could have been some cause for confusion so I made sure to double-check my work before I wired anything. I changed the layout so that when in operation I wouldn't confuse the Voice A and Voice B switches. If you are using your own face plate you may add color coding, use colored (perhaps lighted) switches, or some other creative way to keep everything logical and intuitive.
Based on the size of the components I decided to space them about an inch apart from each other. When I was satisfied with my layout I measured my panel to be 7 inches across and 4 3/4 inches tall.
Step 3: Measuring the Size of the Panel
If you have a new piece of plexiglass or a corner that hasn't been cut before the corner should be square. This isn't a rocket ship so I wasn't too concerned if it was perfect. Plus the edge of my control panel is to be slid into a slot in the wood box I fabricated to house the project so it could be maybe a 1/16 to an 1/8 off before it would be noticeable, but not much more than that.
Instead of using a T-square and making a quick line 90 degrees from the 7 inch mark, I measured the top and bottom points at 7 inches making two marks and then drawing a line between them.
Then I repeated the process measuring 4 and 3/4 inches for the other sides creating my 7" x 4 3/4" rectangle.
Step 4: Making a Template
The control panel pattern:
You will probably want to make a template so you will know exactly where to put your holes. The nice thing about plexiglass is that you can see through it so you don't have to try and mark the surface of your panel. The template could go underneath the glass witch less chance of moving out of position.
If you will notice the plexiglass panel in the images has already been cut to size. This is an earlier illustration from when things went wrong. My initial panel split when I was drilling holes. I will demonstrate how to cut the panel in a later step. I found that it is easier to manage and cut holes into the plexiglass with a larger size sheet.
Laying out the components:
After drawing the exact sized rectangle on my template/pattern I laid out the components within the rectangle to double check that the spacing made sense and that there would be proper spacing between components.
Plotting the points:
I then measured exactly where each part would go and made dot where the center of the holes where to be cut.
Step 5: Cutting the Holes
Determine the size of the holes:
There are several ways to measure the size holes you will need to make. The simplest way is to take the washer from the component and measure the hole. You could even trace the inside of the washer onto your pattern. Since I was eyeballing it, that is along the lines of what I did. You could be more exact by using a micrometer or a Vernier Caliper then choosing the corresponding cutting heads.
Caution with the cutting implement:
I had the good fortune of learning quickly not to use a standard drill bit to cut holes in plexiglass. The second hole I drilled cracked the plate in two when the cutting edge went through the hole and caught the edge of the hole and bit into it making the split. And so I did research on cutting holes in plexiglass. I discovered that about 1 out of 10 tries you will split the plexiglass. Thankfully it happened to me on my second hole instead of my 10th or on my final, the 19th hole, as fate usually deals out.
So if you can't use a drill bit then what do you use?
You have several options, any of which still may split the plexiglass; there is no guarantee.
The first bit I will mention is a Step Drill Bit with which you may progressively cut any size hole. This is good because it starts out small like a pilot hole and then you gradually make the hole bigger. I did not have one of these bits on hand and to buy one would cost between $18-$60 for a set. This seemed the best option as far as risk to splitting the plexiglass, but I had no budget to purchase the bit, plus I didn't want to wait to go and get one or order one.
The second option would be a chamber bit which is a like a sort of a cylinder saw you mount on the end of your handheld drill or drill press. Odds are that you will still split the plexiglass at some point. Now I'm sure there are alternative specialty bits you can buy to drill holes in plexiglass but that wasn't what I decided to do.
The third and preferable option to me was to use what dremel bits I had to grind out the size holes I wanted. There wasn't any time while I was cutting that I felt the plexiglass might split. The downside is that the friction of the grinding melted the plexiglass and put a coating of plastic on my bits. Some dremel bits can be expensive, but in most cases I was able clean the plastic off by grinding with the bit on a piece of metal. If you are concerned about it the be sure to use your cheaper grinding bits. I'm sure results will vary depending on the bits and the thickness of the plexiglass.
Getting ready for the cuts:
One method to aid in the ease of the cut was to put a wooden board beneath the pattern and the plexiglass. This was slow the bit when it poked through the other side of the plexiglass. Also if you may notice in some of the images I lightly clamped the corner of the plexiglass to keep the pattern and the plexiglass from sliding around while I did the cuts. The optimal words being lightly clamped obviously if you clamp too tightly you will indeed split the plexiglass. You should also put a couple of shims or a paint stick in between the clamp and the plexiglass to further protect the surface.
Doing the cutting:
When doing the cutting I began by using a small bit to start pilot holes for each hole. Then I went back with larger bits to increase the size of the holes. I used the components to double check the holes to make sure I got a tight fit. You will notice that on my final pictures of the control panel that one of the holes has a washer over it. That hole I did manage to cut a little too big. This was the hole for the power switch so I didn't mind because it helped to distinguish the switch from the other switches. If I had messed up one of the other switches I most likely would have went back and put washers on all the other switches to make everything look uniform.
You may notice by progressive pictures that I went back and added even more holes as I decided to include additional features and mods.
Step 6: Cutting the Panel to Size
Prepare for the cut:
Notice in the pictures I have lightly clamped the ruler into position along the line of where I want my cut. If you tighten the clamp too much you will of course crack the plexiglass.
The right tool:
I barely remember a time before I had a plexiglass knife. It is a special knife you use to score the surface of the plexiglass along the line of the cut. Scoring the surface is making a groove or a precise scratch where you want the plexiglass to break. Yes, I said "break" because that is what you will do to get your two pieces. Well more of a "snap" than a "break". If you do not make the score deep enough the plexiglass will randomly crack or split. If you score the plexiglass too much or not precisely it will split a bit off from where you want it to split.
"It's a snap!"
Caution! I recommend you wear safety glasses in case something goes amiss and pieces fly at your face and eyes. Now that you have the plexiglass scored where you want your cut you can put your hands on both sides of the score mark and snap it in two. You may use the edge of a table to help make the break, but if you don't line it up properly with the edge of the table your break can easily go wrong despite your beautiful score mark.
Every time I snap the plexiglass like this I always get a nice rush of adrenaline, same thing when I score and break sheet-rock. I always feel like something is going to go very wrong but it rarely ever does. It seems crazy to me but this is the way you are supposed to cut plexiglass. And it is very similar to how you cut regular glass. Before I had this special knife I tried to use a fine tooth saw with very limited success. I wasted a nice expensive stack of plexiglass.
Lightly sand the edges of the plexiglass (being careful not to scratch the rest of the surface). This should help the edges be smooth. With my control panel this was less necessary because the edge of mine will be covered from view.
Step 7: Adding the Components to the Board
This was the fun part for me because you could catch a glimpse of what it we be like when it is finished.
Putting everything in place:
Clean away debris from the edge of the holes. You probably won't need to use sandpaper or anything to clear the holes. With the method I used there was a bit of melted plastic around some of the holes but it is very brittle and cleared away easily with my fingers. If you need to use something to clear it off you may use an Exacto knife or something but beware of scratching your nice clear surface. Keep in mind that the actual edge will be covered by the nut that holds the component in place. Push the components into their holes and lightly tighten the washers and nuts into place.
Step 8: Adding the Wiring
Grounded to the case:
Since the control panel is plastic and the case is made of wood the components really aren't grounded very well. Before adding a whole nest of wires I stripped one long wire bare and wrapped it around the components where they touch the face plate. I left enough extra wire on both ends that I could reach to connect any other components I might add later. This wire grounds all the components together and helps reduce the 60 Hz hum. I considered cutting small plates but decided on the simplicity of a single strand of wire.
Protecting the surface:
This is one of my first major electronic projects. Because I am not yet well practiced with the soldering iron I potentially may linger a bit too long with the soldering iron. In any case it is a good idea to shield the clear plastic from scratches and scorching so I used a thin sheet of tin to cover the surface while I soldered the wiring in place. And for those tiny tight spots I slipped in a dime. You could always wire the components before affixing them to the plexiglass but that could get a great deal more complicated. When all was said and done and everything was connected I carefully took all the components off the plexiglass and washed it with dish soap and water in the sink to clean off the greasy flux spattered everywhere.
Step 9: Solder the Pc Board
The simplest way to wire everything on the board seemed to be just to match everything in the detailed parts list with the detailed letter designations on the board. I started with the resistors and the IC Socket Adaptors, then the ceramic capacitors, the electrolytic capacitors, the diode, and the transistors, and then finally I connected the wires from the control panel.
I did make a few mistakes and had to reorder some parts. As long as I had to get more parts I decided to add some LED mods for the power and the oscillators and I put a 3/4 output jack next to the power switch instead of on the side next to where I planned on putting the power jack.
Step 10: Build a Case to House the Project
Nothing fancy, I built a wooden box and painted it black. At the bottom of the box is a sheet of masonite and the top of course is the plexiglass. There is a slot all the way around the top and the bottom to hold them in place.
Then I sanded the box and painted it black.
Step 11: Finish Wiring & Add the Power Jack
Then all that was left was to plug it in, turn it on and make some weird sounds.
It was just that simple to complete. Over-all this seemed pretty easy for someone with just a few basic skills. Everything is laid out nicely on the MFOS website under the Weird Sound Generator section.
I've added the test demo on Youtube. That brings me to another point. There are lots of demos of these WSGs on Youtube. Make sure you check them out along with Ray Wilson's own MFOS demo videos of all his great musical gadgets. http://youtu.be/BWgKbP5Wf6c