Hodapp’s laser cut business cards are really cool, but they take ~7 minutes each to etch and cut out. I was curious if perhaps we could instead etch a business card stamp and use that to mass produce some business cards.
I did some research and found out that while Linoleum print blocks would be safe to etch, many cheaper print blocks are no longer made from true Linoleum, instead they are made with a cheaper PVC plastic. With that in mind I stopped at a couple hobby stores and picked up a variety of print blocks.
The first one I tested was the one I was most doubtful of, a greyish flexible substance which looked suspiciously like a PVC plastic. The burn tests were not very conclusive, there was no solid bright green flame, but there were spurts of green flame. It was enough that I did not want to risk it.
The second material tested is pictured above and it came through the burn test without any issues and it looked like pictures I had seen of real linoleum with a glue backing.
Using the B/W gradient pattern that Hodapp created I did several test runs to determine how much power would be needed to get a good depth. I also shamelessly stole the Hive13 logo from his project file.
The first result turned out pretty well except for a couple mundane details:
As you can see I forgot to mirror the image, and the thin line that goes around the 1 & 3 is too thin to survive stamping more than once or twice. It still stamped pretty well though:
For attempt #2 I mirrored the image and used Gimp to beef up the outline. Since I was in a rush I did not really try to make it have a super smooth outline after “growing” the perimeter of the logo. This resulted in a rather pixelated border.
Total cut time per stamp was ~30 minutes, but could probably be sped up by optimizing the cut power // speed. Also I think this stamp a fairly large stamp and smaller ones would obviously be faster to cut out.
This idea was shamelessly lifted from another space after Craig showed us a business card cut/etched from cereal box cardboard from them. I think the space in question is in Hawaii. (Update: That space is Maui Makers and Jerry Isdale in particular. Look to the first comment – he posted a link to the card he made that was the inspiration for this.)
Anyhow, no one had yet engraved a bitmap successfully with the laser cutter, so I set out trying to do this (more or less coincidentally – I couldn’t figure out how to export a filled shape from Inkscape in a vector format LaserCut would grok, so I rasterized it).
I tried first on the corrugated cardboard that we have a near-infinite supply of. However, this didn’t engrave well for me – its top layer is too thin and once you’ve burned parts of it off you have only the sparse ridges holding the other parts of it on. Maybe someone else will have better luck with less power. (This is not the first corrugated cardboard issue we’ve had…)
Cereal cardboard, interestingly, both cuts and engraves really well (though in the following photo, I set the power far too high and it visibly burned through). I would have preferred to etch from a vector logo, but it seems easier to get different shades if you start from a raster image and Floyd-Steinberg dither it to a halftone monochrome image, as LaserCut requires monochrome.
The LaserCut file is here: http://hodapple.com/files/hive13%20business%20card.ecp. If anyone wants to make a better-designed variant, please do – I consider this to be just a draft. A faster version might also be good. This one is around 7 – 8 minutes per card, but the speed probably could be cranked up a bit.
P.S. I suffered a cereal-induced sugar headache in the process of making these business cards. You all better be nice to me.
This is an idea cjdavis had mentioned some weeks back: Using the laser cutter to cut out custom filters that mount to a camera’s lens and create custom bokeh shapes. I finally tried it yesterday.
We had on hand a large pile of little card-stock rectangles salvaged from the garbage; we thought they were blanks for playing cards and we had no use for them. However, I discovered, our laser cutter can cut them very quickly, and they are large enough that a 52mm circle fits inside (which matters because 52mm is the filter size of all my lenses).
My first one looked something like this:
…and it fit perfectly inside my 18-55mm lens (perhaps a little too perfectly, because it was sort of a pain to remove…). Here are a couple test images I shot:
I could have centered it better, and I still should calibrate the size a bit, but I’m impressed with how it turned out for something that took all of 5 seconds to cut.
Here’s one with another pattern (this time on my 35mm f/1.8):
Full Flickr album is here. I can have SVGs or DXFs up if anyone asks, but really, these patterns are dead-simple to put together by hand in Inkscape or something similar.
At Hive13 we have a 5′ × 5′ glass block wall/window in our space and the first thing we thought of when we saw it was a 7 × 8 pixel grid.
We want to build a programmable full color, lo-res display using RGB LEDs.
To do this we obivously need LEDs – lots of LEDs. The brighter the better.
We could use these nice ShiftBrite modules, but we’d really rather go all out and get the ShiftBrite’s big brother – the MegaBrite.
ShiftBrites are about $3.50 each and MegaBrites are about $7.75 each. And we need 56 of them. We’ll also need some cabling to connect them all up. The cables are about $1.50 each too. Finally, we’ll need a a good power supply to power it all; that could be as much as $100.
($3.50 + $1.50) * 56 = $280
($7.75 + $1.50) * 56 = $518
All told, we’re going to need somewhere between $300 – $700 to do this. We’re shooting for $400 here. If we go over and get to $700, awesome. If we only get to $300, we’ll make do. Any funds raised here, but not used, will go directly to the Hive13 general fund.
CJDavis and I were at the hive until about 1:20 am this morning working on finishing up a second strand of LED lights for the Glass Block Matrix LED Display.
In this image we are diffusing the LED’s with a sheet of paper towel which causes a nice soft glow, however it greatly reduces the brightness. Therefore we are leaving the paper towels off even though they make for a great picture and viewing experience from inside the bathroom.
We have had some technical issues with both the RGB LEDs and the wiring system we are using. A good amount of the LED’s seem to have an issue where they will turn on even when the anode wire is not connected to anything. We are talking nothing, like it is just soldered into a proto-board. Current speculation is that either the LED’s are bad or the proto-boards are bad.
Another problem we have been having is that originally we were using Cat-5 to wire up each anode for the 8 LED’s in a column, however the current in the twisted pairs was enough to induce a current in the second pair causing issues with LEDs coming on when they are not supposed to. This is a fairly limited problem so far as the LEDs only glow faintly. In any case we are altering how we wire up future anodes.
Sunday December 20th is Arcade Night. This is were anybody who is interested in fixing up arcade machines or building your own game system or augmented reality game should come and collaborate! Starting at 5pm on Sunday show up to help out or start your own project. We will be fixing up several standup cabinets as well as the rather large arcade units.
Note: This is not a night to play arcade games but to build/refurbish them. Although we will always need to test our final products, of course…
I had some spare time down at the hive last night so I finished assembling the framework for the RGB Glass Block Matrix display. The next step is going to be to mark out where to drill the holes for the LED.
After that is done we can start soldering up the LEDs.
A few of our members stopped up at the UC surplus sale on saturday and picked up a couple of largeish projectors. One of them had a working bulb and a bad powersupply ($25), the other had a bad bulb ($50).
After moving the bulb from the projector with a bad powersupply to the projector that just had a bad bulb we discovered that we now had a very nice working projector.
This should provide a nice start for our Laser Graffitti projects, also, we still have the other projector that needs a new powersupply but could serve as the base for testing more powerful light sources.
This is another project initiated by PlayerTwo. This is an older arcade game called Meltdown. The way the game works is the game will move a goal box up and down a center tube. Inside the center tube is a radioactive sample that the gamer must keep centered inside the goal box by adjusting the flow of the air through the center tube.
The main problem at the moment is that the goal box is on a cable that keeps getting snagged and is a bit stretchy so it slips. Once this problem is worked out there is a bit of surface work that needs to be done.
Hive13 aims to create a place where a diverse community of makers can collaborate and pursue creative projects. Hive13 promotes science & technology education, open source values, and skill sharing amongst it’s members and the community.