Want Bookshelf - Got Hackerspace, Don't Need IKEA

A couple of our members who haven't been able to come around HackRVA for awhile we're having lunch and discussing their need for a bookcase. At first they considered making the trek up to the NOVA IKEA, but then were like, "What, no, we can make it ourselves, lets go to hack".

After finishing lunch, they moseyed over to a big-box for wood and hardware, then they came to HackRVA during what happened to be a Saturday hackathon. They had plenty of help with tools and lots of admirers. By the end of the day, a lovely bookcase was created.

We even loaded up the finished product in the car together to see it on it's way home. It came a pile of materials and left something awesome.

 I was blown away by the quickness!

One Saturday at HackRVA and they have a piece of furnurture that looks beautiful and they'll always remember building together. Forget gnarly I-95 trips to IKEA, make it at HackRVA!

More pics below after the break:

Megaldon Tooth Casting

I've been wanting to get into mold making and casting for at least a year. I just wasn't sure how to get started. I finally took the plunge with this kit from smooth-on.com.

I did this at last weeks HackRVA Saturday hackathon, which happened to be the "Make your Spirit Animal" event held by WoHack.

I wasn't sure what to cast, or what to make my spirit animal... then I remembered my "meg" tooth. Therefore my "spirit animal" or as what spectators rephrased as my "power beast" became the Megalodon. And I cast the tooth right up.

Smooth-On.com is a go-to site for learning how to cast things.  They have tons of how-to videos. For me it was almost overwhelming. I finally settled on the starter kit linked above.

My lessons learned where:
1) Mix in a bigger container. When you put the rubber silicone mold material together, you have to stir slow and methodical. You also have to get it to blend completely, leaving a pure purple from the pink and blue compounds combined. I lazily tried to mix them in a narrow container and left some material not mixed. The mold turned out fine, but I would have done better with a large container.

2) The plastic casting material sets up fairly quick, and gets hot. Nothing went wrong there, but if I'd walked away from it, my solution would have solidified before I had a chance to pour. And like I said, it gets pretty hot. Don't be surprised.

The cast came out great. So detailed that I could see the grain of the tooth's enamel decay.

For more pics, check out after the break. Looking forward to more mold making and casting experiments at HackRVA.

Learn to Solder badges for RVA MakerFest

We knew we wanted to teach people how to solder at RVA MakerFest.  Estimates put the need at anywhere from 20 to 300 badges.  We looked at various kits, but without knowing how many people we’d be teaching, they were simply too expensive, too complex, or not available in the needed quantity. 

As the date drew closer, we still hadn't found a suitable board to use for teaching people how to solder.  At (what seemed like) the last minute, we decided to design our own badge.  Once the board was designed, there wasn't really time for a prototype run, so we crossed our fingers and ordered the full batch of PCBs from ITead.

It’s a very simple schematic, and the board can be soldered in less than 10 minutes, even without any prior soldering experience. 

The circuit is about as simple as it can get, simply 2 LEDs in parallel with a battery.  The current limiting resistors are omitted due to voltage drop and the internal resistance of the battery.  We used blinking red LEDs due to the low forward voltage drop, but the blinking RGB LEDs can also work in this design and would probably last longer.

The schematic and board layout were created in Eagle CAD, and Itead provides a CAM job to create the gerbers.  The most difficult step was creating the silk screen image.  I followed a tutorial on Instructables called Adding Customer Graphics to EAGLE PCB Layouts.  It took a few minutes of playing with the bitmap import settings to get it to look right.  

Placing the order was straight forward following the instructions provided on the product page (although the process has now changed to upload on their site).  These boards were ordered on a 1.2mm red PCB with 1 oz. copper.  Although they offer very low prices compared to local houses, shipping nearly doubled the cost!  Overall, Itead was an excellent choice for such a simple board.

I didn't consider the additional thickness from electroplating the through holes, so the pin didn't quite fit.  It was possible to force it in with a pair of pliers, but it wasn't always successful, and just wouldn't work at the event.  I ended up manually drilling each board with a 1/16 inch bit. 
The pads for LEDs were also a bit small for beginners.  They should have been enlarged a bit to make things easier.  
The stainless steel pins are a real pain to solder.  Maybe they should be glued or something else next time. The pins had a large (12mm) head.  Headless pins would be a better choice.  We’ll get started a bit earlier next year, and I hope to try a interesting board outline.

Of course, since there wasn't a prototype run, there were a few issues. 

• The pin didn't fit.
• Pads were very small.
• The pin was very difficult to solder to the board.

I didn't consider the additional thickness from electroplating the through holes, so the pin didn't quite fit.  It was possible to force it in with a pair of pliers, but it wasn't always successful, and just wouldn't work at the event.  I ended up manually drilling each board with a 1/16 inch bit. 

The pads for LEDs were also a bit small for beginners.  They should have been enlarged a bit to make things easier.  


The stainless steel pins are a real pain to solder.  Maybe they should be glued or something else next time. The pins had a large (12mm) head.  Headless pins would be a better choice.  We’ll get started a bit earlier next year, and I hope to try a interesting board outline.

Download the Eagle files
Download the gerbers