LEGOlamp

LEGO_lamp_2_complete_dark   This is the assembled LEGOlamp.  It will be mounted as a ceiling fixture, with an internal bulb.  To light it for this picture, I used a desklamp to project light into the tube.

One idea I tried after the previous post, was slicing the tube into 16 rings.  The idea was to glue the bricks to the tube, with the bricks stacked vertically, then offset the rings after the bricks were attached.  That approach failed.  I was unable to cut the rings smoothly, resulting in large gaps between them.  When stacked, they looked horrible.

In the end, a simple change of adhesive and application made the difference.  First, I abandoned both hot glue and epoxy.  I discovered gel super glue has sufficient open time to position the bricks, but also sets quickly enough that clamping and supporting the bricks was unnecessary.  I addition, I realized the important joint is between the bricks.  If the bricks are firmly cemented to each other, the connection to the tube can be a series of comparatively weak joins.  Less glue on the end-face means less glue to smear, and less chance of accidentally gluing the template in place.

 

drillpress_dremel_saw  Many people have asked how I cut the LEGO bricks.  Initially, I used a sharp chisel.  That was tedious, as each brick had to be clamped.  After that, I switched to a rotary-tool held in a fixture, with a standard abrasive cut-off disk.  That worked well enough.  Finally, I hit on chucking a Dremel-sized circular saw blade into a drill press.  That provided a rock-solid platform.  Better still, once the height was set it didn’t vary.  Unlike the abrasive disk, the bricks weren’t heated by the saw blade.  No molten plastic flying around.  Using this method, the bricks required little-or-no touch-up work with a sharp knife.

Ho Ho Lights

My Husband and I wanted to put up some kind of Christmas decorations in our apartment windows over looking the city. After talking about it for a while, I decided to make lighted letters saying, “HO HO HO” …but since we only have two pairs of windows, it would have to just be, “HO HO”.

In the wee hours on Black Friday, we got the materials: 4 sheets of wood, 4 boxes of 100 count LED lights, and extension cords. After sketching out the design…

…and cutting out the letters…

…it was time to drill the 400 holes and hot glue all the lights in place.

It only took a weekend to make and hang these and I think the end result is well worth it.

MAHRER CHRERSTMAHS

LegoLamp follow-up

There are some issues . . .

It’s not going so well . . .

In a previous post, I outlined the plan for constructing the LegoLamp.  It was good theory, but not really workable.  This post will be a “what I learned,” rather than “look at what I built.”  The picture tells the story.

Legos are rectilinear, the cylinder is not.  Which means the contact between them is a line.  That’s not a lot of gluing surface.  Ideally, I would have cut the brick-end to match the curve of the cylinder.  But Lego are hollow.  Removing that much material would have removed the end of the brick.  I counted on the relatively thick hot-glue adhesive to smoosh, expanding the area of the joint.

The laser-cut template has very tight tolerances.  This was deliberate.  Making the template tight allowed it to serve, in theory, as a substrate for the next layer of bricks.  The tight fit to the current layer of bricks would hold the template perpendicular to the cylinder.

In the background, you can see the hot-glue gun has been retired.  There is a yellow, plastic-razor-holder next to it.  Hot glue was not the proper adhesive for this job.   I installed, removed, and scraped, 3 layers of bricks — twice — before abandoning the hot glue.  The template is so tight, it leaves no room for adhesive.  The glue gets scraped-off and smeared onto the cylinder as the brick is fit.  After the first layer, placing a brick is not merely a matter of fitting it into the template.  The template must be aligned with the lower layer of bricks so that the new brick will snap onto the one beneath it.  The glue is not-so-hot by the time the template is properly aligned and the brick is inserted.  The resulting joint is weak.

I switched to two-part epoxy, to gain a longer working time.  In short, it still wasn’t sufficient.  Five minutes was long enough to place the persnickety first brick of a row, plus 3 more.  Then the epoxy became unworkable, and I had to dispense more.  I wasted a lot of epoxy.  Adding insult to injury, the working time was 5 minutes but the minimum set time was 20.  That means 30 minutes per layer.  Sixteen layers is 8 hours of gluing.  That’s too long.  And, the epoxy had the same smearing and small-contact-surface issues as the hot glue.  Some of the epoxy joints are no stronger than the hot-glue joints (i.e., they fall apart if touched).

The template works as a substrate for the next layer of bricks.  But the etched outline is not sufficient to accurately place that next layer.  When the template is rotated & raised to lock onto the 2nd layer, it doesn’t fit.  The bricks are not placed within the tolerance of the template.  I can’t use the template to support the new layer as the glue sets.  Without that support, the bricks tend to fall out of parallel as the adhesive sets.  This makes the next layer even more difficult to place, stresses the lower layer’s joint in the process, and results in collapses like the one in the photo.  I created support structures from other pieces of Lego.  These work for the initial layers.  But they add to the difficulty of placing a brick.  They can’t be used after the first 5 layers, because there’s no space for them.

Clearly, it’s time to back away from the project and rethink it.

Hack-A-Lantern: DIY Salvaged Zombie-beatin’ Flashlight!

Recently, I was hanging out at the Milwaukee Makerspace, working on a simple project, when a fellow Maker offered me a used 5AH lead acid battery.

The project I was working on involved using landscaping lighting, and right there on the “Hack Rack” were some old computer power supplies. Hmmm. We also happened to be talking about Zombie movies and TV shows, when it all clicked – I have the skills and materials to build an electric lantern from scratch using just the materials that are right here!

The project started by taking apart a computer power supply. I snipped the wires from switch and power cord connection close to the circuit board, so that I would have plenty of wire still soldered to the switch. After removing the circuit board and cooling fan, I had a nice empty box to use as the case for the lantern.

Next, I snipped out the fan grate, to allow for the 12V 11watt landscaping light bulb. These things are designed to run on 12AC from a transformer, but nothing is stopping me from running it on a 12V battery instead!

I crimped on a couple of spade connectors onto the wires from the switch to go to the battery and the bulb. I also wired the power port so that it was unswitched (always connects to the battery) that way, I could use it to recharge the battery without having to open the case. I would just clip the external battery charger that I already had to the two pins of the port.

Once the wiring was done, I checked the connections, turned it on and off a couple of time, and then glued the bulb in place with silicon.

A key feature of a lantern (as opposed to a flashlight) is that it has a distinct handle on the top, which the lantern hangs from. When I’ve made handles before, I’ve usually used a pair of bolts with spacers and some sort of cross-piece of wood or metal. However, I didn’t have anything like that handy, and it didn’t seem to fit the theme of the lantern either.

I DID have all the extra wiring from inside the power supply. The main bit of it was already bundled and had a nice connector on the end. I drilled two 1/2″ holes in the case cover and ran the cable through it, then back through the other hole, and pinned it in place with a few zip-ties.

I also glued two bits of foam on the inside of the case to cushion and help hold in place the battery. With that I put the cover back on and reinstalled the four cover screws.

There ya go! A lantern made completely from repurposed, recycled, and salvaged materials! Whether you like tinkering, being ready for the zombies, or just like being prepared, the Hack-A-Lantern is for you. Why don’t you try making one and see what you come up with!

More DIY Eco-Projects at http://ecoprojecteer.net

LEGOlamp

Materials:

  • Clear acrylic tube, 3″ O.D.
  • 4×2 LEGO bricks, 6 per layer
  • Ceiling-mount shade holder (like this one)
  • Hot glue or specialty adhesive (e.g., Weld-On #1802)
  • Template material (flat, at least 6″ square, 5/16″ thick)

Initial considerations:

3″ O.D./2.75″ I.D. tube is appropriate for a ceiling-mount shade holder.  That greatly simplifies the wiring and allows a standard bulb to be used.  Incandescent bulbs get much hotter than CFL bulbs.  Airflow around the bulb is likely to be restricted.  Cooler bulb is better.  Distorted or discolored acrylic is not pretty.

Acrylic tube is not the only option.  Transparent PVC and polycarbonate are also viable.

Spacing between “vanes” is important.  Because the light-source is inside the bricks, they will cast dramatic shadows and restrict the amount of light projecting into the room.  The 3 screws attaching the tube to the shade holder require equidistant holes.  Space must be left for them.

A child may not understand the difference between decor and toy.  A ceiling mount places it out of reach.  The 3-screw attachment should be easily adaptable to other mounts, should they be desired later.

Template illustration

Each brick hinges on the corner nub of the brick below & behind it.  Thus each one is half a brick ahead of the one below & behind it.  Brick edges are straight, so the ends will only touch the tube at their centers.  A triangle, formed by the center of the tube and the centers of connected bricks, has a vertex of 12° (see illustration).

Use a template to ensure the bricks are glued in the correct orientation and spacing around the tube.  The template has brick-shaped holes for already-attached bricks, and indicator-lines showing where the next brick should be placed.

Correct thickness of template

 

 

 

The thickness & rigidity of the template material are important.  In this illustration, the template rests on the red layer of bricks, is held in the correct orientation by the yellow bricks, and supports the new, green, bricks while the glue sets.  If the template is too thin, the leading edge of the new bricks will drop.  Instead of stair-stepping up the side of the tube, the “vanes” will droop and level-off.  If the template isn’t rigid (say, cardboard), it will flex under the new bricks with the same result.  (I used sheet acrylic.)

The correct thickness of the template is equal to the distance from the bottom of the new layer of bricks to the top of the nubs on which it rests.  Note that this is not the same as the thickness of a brick!  It’s the thickness of a brick, minus the height of its nubs, then minus the height of the nubs on which the template rests.  7/16″-1/16″-1/16″=5/16″.

Construction:

The Tube:  How long should it be?  As long as you want.  In my case, I noticed that 6 inches is an even multiple of the brick-height (3/8″ per brick * 16 bricks = 6″).  So my tube is 6 1/2″ long.  The extra half-inch is to accommodate the nubs on the topmost layer of bricks and provide clearance for the shade-holder.  I cut the tubing on a table saw.  The technique recommended by the manufacturer is to raise the saw blade to just above the thickness of the tubing, then rotate the tubing, in place, on the blade.  In my case, I used a cross-cut sled to ensure the cut was perpendicular all the way around the tubing.

The LEGOs:  16 bricks per “vane” * 6 vanes = 96 bricks.  I decided to use equal numbers of each color, so I needed 24 bricks each of red, yellow, green, and blue.  I purchased used bricks and a large LEGO plate in an on-line marketplace.

Don’t cut the red ones!

Because each brick must rotate 12° relative to the brick on which it sits, 3 of the 4 nubs must be removed from one side of each brick.  Important: Decide which way your bricks will rotate before you remove the nubs, and remove the same 3 nubs from each brick!  In the illustration, the red nubs are closest to the tube.  Do not cut those!  Those are the pivots for the bricks that will attach to them.  If you want the bricks to spiral clockwise up the tube, remove the blue nubs.  If you want counter-clockwise, remove the green nubs.  Note: you don’t need to remove the nubs from the top-most 6 bricks.  In fact, it will probably look better (from the ceiling, anyway :~) if you don’t.

My set-up for removing the nubs

 

 

 

 

 

 

I used a rotary tool, fixed in a stand, to remove the nubs.  I used a standard cut-off disc.  I adjusted the height of the tool so that the bottom of the disc was at the bottom of the nubs.  I used a big, green LEGO plate to hold the bricks in place, while I cut them.  The plate allowed me to keep my fingers well-away from the spinning blade, but still manipulate the brick being cut.  I left a gap between the pivot end of one brick and the next brick.  This made it easier to avoid accidentally removing the pivot nubs.  (Note: molten plastic is hot.)  After cutting, the bricks required some touch-up work with a knife, to remove the plastic still attached to the edges.  Also, the nubs are discs that sit atop holes in the brick.  Removing the nub reveals the hole.

Laser-Cut template

The Template:I found some scrap acrylic of the correct thickness. Shane was kind enough to redraw my template sketch as a vector, and show me how to use the Makerspace’s laser-cutter (Thanks, Shane!).  We cut the template in multiple passes.  The first pass included the outline for the “next-up” brick.  Subsequent passes did not.  That produced the desired through-cut with adjacent guidelines.

Template test-fit

 

 

 

 

 

This image shows the template, a short length of tube, and a pair of test bricks (3 nubs have been removed from the red brick).  Notice how the template aligns the red brick, and how the guidelines show correct placement of the blue brick.  Note: The template is resting on the table, not on a lower layer of bricks.  That’s why the blue brick doesn’t rest on the template.)

That’s as far as I’ve gotten.  I’ll post again when the project is completed.