Notes:
- READ INSTRUCTIONS BEFORE STARTING.
- Use a PVA type glue, like wood glue, Weldbond, Elmer’s, etc. Apply sparingly and clamp 10 minutes to set. Allow 24 hours to cure completely before sanding, painting, installing modules.
- Work on a clean, flat surface. The work surface can be used to align parts.
- Power supply requires a 12V AC adapter. 15V AC will work as well but the power regulators will get much hotter and may need better heatsinking if powering more that 800mA per rail.
- Adapter should be 1.5A or greater. 12V 1.5A to 2A adapters are very common. 12V AC adapter are available up to 3.3A.
How it works: Thanks to the regular 1U Tile mounting hole placement and stiffness of the 1U Tile panels it’s possible to trap M3 nuts between two layers of lasercut hardboard and very firmly hold 1U Tile modules in place. To ensure there’s enough glued wood between the trapped nuts to stop them from spinning only every second mounting hole is used, leaving the top left and lower right mounting positions available per tile (or double-tile, triple-tile).
BOM:
Qty | Value | Device | Package | Description | Notes | ||
---|---|---|---|---|---|---|---|
6 | 1n4007 | DIODE | DIODE | 4002 to 4007 okay | |||
2 | LED | LED 5MM | LED | ||||
2 | Shrouded Header | 2X5-SHROUDED | Eurorack Power Header 5x2 | ||||
2 | 100nF | Capacitor | C025-024X044 | CAPACITOR | |||
2 | 100uF 25V | Polarized Capacitor | E2,5-6 | POLARIZED CAPACITOR | If using 15VAC use 35V rated capacitors. | ||
2 | 10uF 25V | Polarized Capacitor | E2,5-5 | POLARIZED CAPACITOR | If using 15VAC use 35V rated capacitors. | ||
6 | 4700uF 25V | Polarized Capacitor | E7,5-16 | POLARIZED CAPACITOR | If using 15VAC use 35V rated capacitors. | ||
2 | 4.7k | Resistor | 0204/7 | RESISTOR | |||
1 | 7812 | Power Regulator | TO220 | Positive VOLTAGE REGULATOR | LM7812 or L7812 -- NOT LM78L12 (low current) | ||
1 | 7912 | Power Regulator | TO220 | Negative VOLTAGE REGULATOR | LM7912 or L7912 -- NOT LM79L12 (low current) | ||
1 | AC | Terminal | Power Header 1 (OPTIONAL) | ||||
1 | 3A | PTCPTH | PTC | Resettable Fuse PTC (OPTONAL) | |||
12 | Tile Power | Futaba J | Eurorack Tile Power Tail OR 3-pin header | http://www.hansenhobbies.com/products/connectors/leads/exlead_fut22-12/ | http://www.taydaelectronics.com/connectors-sockets/wafer-housing-crimp-terminal/serie-2500-2-54mm/wafer-connector-2-54mm-3-pins.html | ||
Hardware: | |||||||
2 | Heatsink | PCB horizontal | Heatsink | If using 15VAC a larger heatsink may be necessary for >1A. | http://www.dipmicro.com/store/HSINK220B | https://www.digikey.com/products/en?keywords=Wakefield-Vette%20274-1AB | |
2 | M3x8mm | bolt and nut | for heatsinks | ||||
2 | Heatsink Insulator | TO220 | http://www.taydaelectronics.com/hardware/heatsink/transistor-rubber-washer-to-220.html | ||||
1 | M3 | Heatsink Bolt Bushing | For negative (upper) heatsink | http://www.taydaelectronics.com/hardware/heatsink/insulation-bushing-to-220.html | |||
1 | SPST | Switch | mini toggle switch | Other toggles will fit. | http://www.taydaelectronics.com/electromechanical/switches-key-pad/toggle-switch/mini-toggle-switch-spdt-on-on.html | ||
1 | 2.1mm | DC Power Jack | Other jacks will fit by widening hole | http://www.taydaelectronics.com/hardware/dc-power/dc-power-jack-2-1mm-bulkhead-type-panel-mount.html | |||
4 | Rubber Feet | Max. diameter 15.5mm. With ~3mm hole for bolt. | |||||
36 | M3 | nuts | |||||
4 | M3x12mm | bolts | For mounting Rubber Feet | ||||
9 | m3x10mm | bolts | For mounting PCB | ||||
24 | m3x8mm | bolts | For installing panels. Can be 8mm to 12mm. |
Other:
- Wood glue
- Small clamps (clothpegs, binder clips, rubber bands)
- Weight for clamping
- Flat clean worksurface
Finding 1U Tile “Futaba J” Power Connectors
Tile connectors can be found in your local hobby store, on eBay (look for sellers selling 10 or more “extensions”), or online hobby stores. They will probably be crazy expensive at your local hobby store. Bought in bulk on Ebay is inexpensive, but the “male” part may not be polarized. Both of these are “extension” cables, so you need to cut them to size — and you’ll get a free connector for Tile modules. The last option is inexpensive and is shipped from the US so is quick.
Another (experimental) option is to ditch the Futaba connectors and just use male 3-pin headers. The pin size and pitch is the same as the Futaba J connector. However these are not polarized so attention needs to be taken when adding modules. In the bottom row of the the PCB shown here polarized 3-pin headers are used, with the polarization tab oriented like the 10-pin Eurorack header (-12V on left when notch is toward bottom). This polarization tab isn’t used for polarization, but to put pressure on the pins for a secure connection. There is a white stripe on the PCB to denote the -12V pin.
Building
The kit will contain the following:
Begin by removing any tape (shown here as green, may also be blue), and bits left in holes.
The laser cut pieces have two sides: The TOP where the laser pierces the surface have smoke marks and darkened edges. The BOTTOM have what look to be “water stains” where moisture/oils were forced out by the laser.
We will orient all the pieces so the TOP’s are all on the outside of the case and BOTTOM’s are on the inside. Almost all the pieces are cut symmetrically so for most of them it doesn’t matter which way they’re facing — it just looks neater.
Start by gluing the top pieces together in the order shown. Keep the “top” side upwards so the holes begin in the upper left corner.
When gluing use a very thin bead of glue and spread it evenly over the parts in contact. It’s important to get glue completely around the hexagonal holes as this is what prevents the nut from spinning.
First glue the bottom and middle pieces and clamp together.
The bottom piece is has the notches in the side, and the middle has the hexagonal holes.
The top piece has smaller holes like the bottom — don’t glue this yet.
Ensure that the edges are perfectly aligned before clamping.
Once these are dry we’ll add the nuts and glue the top on.
While waiting for that to set, we’ll make the bottom panel mounts.
There are four of these, each with three pieces plus a nut.
Glue the one with the hexagonal hole to the fish-shaped piece, place an M3 nut in the hexagonal hole, then glue the piece with the small hole on top, trapping the nut inside.
Make sure that the edges are aligned and there’s a clear path for the bolt through all the pieces.
Remember to use a very small amount of glue, spread evenly over the mating surfaces.
Clamp them for at least 10 minutes.
Unclamp the top piece, and fill the hexagonal holes with the M3 nuts.
Glue the final top piece on top, trapping the nuts inside.
Remember to glue completely around the hexagonal holes.
Make sure the edges are aligned before clamping.
Clamp for at least 10 minutes.
While waiting for that, let’s make the rest of the case.
Dry fit the pieces to ensure that the pieces are oriented properly.
The “tops” of the pieces should be facing downwards since this is the inside of the box. Note that the ventilation holes are on the left side.
The front (bottom-most in this picture) is just slightly smaller than the side pieces. They won’t fit together tightly like this if in the wrong order.
Also note that there are tiny notches cut into the bottom corners for the bottom panel mounts.
The bottom panel mounts we made earlier fit into these tiny corner notches.
The sides and bottom panel mounts need to be installed together.
Glue the sides of the panel mounts and the side notches of the panels and fit together.
DO NOT GLUE THE BASE PANEL TO THE SIDES! Use the base for alignment, but try to keep it from getting glued to the sides accidentally.
Try not to overglue. This is way too much.
Note how the bottom panel mount fits into the side.
The bottom of the panel mount should line up with the top of the notches.
Use rubber bands to clamp the corners. It doesn’t have to be too tight.
The base panel can be used to check if it’s square.
While waiting for that to set, glue the PCB mounts to the inside of the base panel.
No clamping is required. Just make sure they’re centered.
Unclamp the top piece, and glue it to the sides.
If should be safe to attach the bottom as well. Don’t use screws to hold it on, just add a few more elastics to hold everything together and square while the glue sets/dries. Watch that you don’t accidentally glue the bottom.
Give it at least 30 minutes to set.
Afterwards glue the edge trim to the top.
Once it’s aligned square to the edges, turn the case over and put some weight on it to clamp the trim.
Here are some reference pictures…
The power PCB and cabling can be installed
after it has dried for an hour or two.
Give the box 24 hours to cure fully before sanding, painting or installing modules.
The outside of the box should be sanded to remove glue and laser residue before painting.
Here are some reference pictures…
While waiting for that to dry let’s make the PCB.
Clean PCB with isopropyl alcohol before soldering.
There’s nothing tricky here. Some of the capacitor values may be different than the BOM (use the BOM values). 4 1N4007s are around the regulator, and two are located at the AC power input.
There’s stitching around the regulators to help transfer the heat to the bottom copper of the PCB. They can be filled with solder, but I didn’t notice much of a difference when using a heatsink.
Tile Power leads can be used. I’ve been experimenting with 3-pin male headers instead (in the first row here). This can be awkward unless the power “tail” on the tiles are long or you have abnormally thin and long fingers.
Triple check polarities before powering for the first time!
The negative regulator (left here) need the tab isolated from ground. This means that the heatsink needs an insulated rubber or silicone washer for the heatsink and an insulated bushing for the screw that holds the regulator to the PCB.
Screw terminals can be used on the power input, or the wire can be soldered directly to the PCB.
The PTC has been jumpered here. The regulators have over-current and over-temperature protection already. If you did want to use one though it should handle 3A continuous current.
DC jack wired through the SPST toggle switch.
Other types of toggles and jacks will fit by drilling-out the mounting holes.
The bolts that hold the bottom on can be used with rubber feet.
Otherwise stick-on feet can be used too.
I found these rubber feet locally. Currently looking for an inexpensive online source.
When mounting the PCB ensure that the heatsinks are over the ventilation holes.
Once the electronics are installed on the base panel, it can be put in the case
FINISHING
Hardboard is easily painted. Lighter colours will need several coats.