Pawbital – Orbital style glasses for cats

I friend of mine wanted to dress up her cats for Halloween. She asked me to make some glasses with lights in them like on the Orbital 20 album cover.

P1040122

I started by making a design for the actual glasses. They are made from 1/4″ MDF and cut with a laser cutter. We had to do some test fittings with a cat. She tolerated it pretty well. Her unhappy look is due to the camera flash.

Cat Glasses Layout

 

Once we got the glasses to fit reasonable well, I went back to the pattern and cut some holes for the electronics. One little watch battery goes in each side and the LED’s are 3mm white through hole. I just super glued the lights on. The batteries and switch were held in place with some black heat shrink tubing.  I soldered wires directly to the batteries. This is tricky as I overheated one and it had a containment failure.

 

 

PawbitalThe wiring diagram is pretty simple. The LED’s I chose were 3.3v forward current. The internal resistance of the watch batteries is enough for this application and no other resistors are needed. I hand soldered the wires and glued them out of site along the frames.

Pawbital Fruit

The cat’s didn’t want to hold very still for the photos, so here are their stunt doubles showing off the lights.

 

Posted in Laser

ExtraCore V2 final production design checked in

The files eagle files with Gerbers are checked into GitHub here. The github version is 1.5 but the “marketing” name is V2. I know it’s confusing, but if you are the sort of person to download your own eagle files/gerbers I think you can deal with it.

There are some minor changes to the the top silkscreen since I took these photos but the physical design is final. I upgraded the GND/VCC traces to be able to handle the full 1amp of the power converter. As always with Arduino don’t source or sync more than 400ma via the chip. But if you need a bit more power you can tap it off the VCC pin now.

I got two boards from Sunstone today. Here is how the front and back looks. I added a ground plane. Partly because with the on board regulator I am worried about heat and the ground plane should help to dissipate it.

Front and Back

I fixed the major silk problems from release candidate zero. But I let a couple of minor problems slip by.

RC0vsRC1

Silk Errors

Once I examine the boards and made sure they came out all right it was time to add solder paste. Rather than use a solder mask for a relatively small number of pads I used a zipper bag with a hole in the corner to pipe the paste on like decorating a cake. Sorta. The solder paste isn’t very sticky so I also used a sewing needle to push it down where I wanted it. Having a microscope is pretty helpful. I have made do in the past with a magnifying glass and a loupe.

Solder Paste

Next I just used some tweezers to lay down the components.

Components PlacedFinally I used my new hot air rework station to heat up the solder till it melted. Easy. You can also do this step on a hot plate. I find boards with a ground plane are a bit harder to manage on the hot plate.

After that I flipped it over and did the power regulator. The hotair rework station makes doing a back side easy. If you are using a hot plate you would have to do the back by hand. There are 8 solder junctions so it wouldn’t be a problem and I have done similar stuff by hand before with little trouble.

The hot air station really saved the day when I realized I was out of 1K 0805 resistors. I was easily able to salvage one from a prototype board from another project. I have removed resistors with a soldering iron by hand before and it takes 10 times longer.

The next step is to do a little math and get a fundraiser going on tindie.com.

Posted in Uncategorized

Lots of new dog themed items added to the Etsy store

My sister shows her Belgian Tervuren “Mighty Supernova of Earlymoon” (AKA Nova). She has been asking for some dog stuff and I have delivered it to my Etsy store.

I can now do keyrings, coasters and treat bags with any breed of dog. I only have artwork on hand for two breeds right now, but I can add a new profiles on demand within a day.

Leather is a fairly new medium for me, and I am starting to really enjoy working with it. Being able to laser cut the patterns and stitching holes makes it easier to work with than traditional tools for me. The hand stitching adds a personal artisan touch that I also like. I haven’t quite got the hang of using leather dye yet, but my current products don’t really on it.

 

Posted in Etsy, Laser

ExtraCore V2

The last of the V1 ExtraCores have sold out. About 600 of them sold in one year. The majority were sold on the Kickstarter. I’ve been working on a V2 design, but it’s been on the back burner. There are a lot of factors involved in that. Read to the end of the post if you are interested in my ramblings on that subject.

 

Meet ExtraCore v2

Top

What is ExtraCore?

ExtraCore is a postage stamp sized Arduino Uno compatible board. V1 came with an external power regulator cost $10.50.

What’s the same?

Well, practically everything. Same layout, same components, same size, same Atmega328 pins exposed. This is the working prototype of V2. Other than some problems in the silk screen it’s 100% ready for production.

What’s new?

Raw Power pin

One of the ground pins has now been replaced with a RAW power input pin. This means you can power the board without the need of an external power regulator. Moreover, you can tap into clean 5v from the VCC pin if needed. In other words, you can connect a 9v battery right to the RAW pin.

 

Bottom

I’ve added an AP1117E50G-13 power regulator to the back of the board. The regulator can take up to 18v, but the board may not be able to sink that much heat. The regulator can also supply up to one amp of power. That’s more than the Atmega (and possibly the power traces) can use.

When can I get one?

The design isn’t quite final. The prototype is working, but I want to beef up the power traces and test the power regulator some more. There is also still the matter of finding a manufacturer and a way to take pre-orders. In order to make the board cost effect, at least 1,000 will need to be made. http://tindie.com now does fundraisers so that’s the most likely platform for taking pre-orders.

V2 back story or why it’s not ready for ordering yet

For one the Robotic Minion Starter kit took up a lot of time. I got a laser cutter in order to make enclosures for that product. It turned out to be a versatile tool with a lot of possibilities. Getting new laser cut designs out and for sale is much faster than the cycle for electronics. As I try to build up a sustainable business I have focused on getting more products in the market. That means the laser cut projects are getting priority.

Another thing that happened was a change in the rules for Kickstarter projects. Specifically you can only offer one reward per customer. So no more 5 and 10 packs. For the ExtraCore that really doesn’t make sense. Kickstarter built the best pre-order marketplace in the world and decided it wasn’t what they wanted.

The last thing that happened was the manufacturer I used for ExtraCore V1 has politely declined to do V2. That leaves me looking for another place to have them made. Since I quit my job and I am living on savings, I can’t afford a project that is going to break even or possibly lose money. On the other hand I am passionate about keeping the price point of the ExtraCore as low as possible. If you want a tiny Arduino clone and are willing to pay $25, the Femtoduino is a superb package. I don’t see any value on trying to compete head to head with such a great product. Instead I want to offer a real choice to Arduino users.

Posted in Arduino, Open Source Hardware, PCB

3 more leather flasks

I made 3 more flasks. The leather, once cured in beeswax, is quite hard. Like a hard, slightly flexible plastic. If you rap a knuckle on them it makes a very solid thock. Between laser time, materials and labor I would have to sell these for at least $60 to justify making them. I will probably add these to Etsy for a bit less since they didn’t come out how I wanted.

Flasks 552

The next photo is out of the other half of the failed map from before. This one has “Mordor” if you look closely. I made the sewing holes a 1.5mm on this one and used black thread and a saddle stitch as opposed to the lockstitch I used before. I’m not at all sure the stitch style matters but the smaller holes worked well.

LOTR 556

The next flask was with a new map. I used an 1848 map of the “Oregon Country” from the public domain. I made the opening for the cork slightly narrower. When the cork is dry, it fits a little more snugly now. Sadly I didn’t get the map lined up with the pattern as well as I wanted and it’s off center and doesn’t cover the back all the way. I’m not sure it’s a bad look, but it’s not what I planned. I did etch the map more deeply and the details are a lot more visible. I also dipped them in slightly cooler wax which seems to have not darkened the leather quite as much. The map details really came out. The more subtle look of the first two flasks is nice too. I am not sure what a prefer.

 

Oregon 557Oregon 558

 

 

 

 

 

 

The final one, pictured below, came out how I wanted it.

Oregon 560 Oregon 559

Finally I created a cork retainer for the first flask. It worked out OK, but I have some ideas for improvement. I am considering drilling a hole through the corks to pass a leather cord. If only I could find my bag of leather laces I know I have around somewhere.

LOTR 554

Posted in Laser, Leather | Leave a comment

Leather Flask with Laser Etched designs

I have been experimenting with laser cutting and etching leather. I came across this Instuctable and wanted to try something similar. I had laser etched a map I wasn’t 100% happy with on some leather. So I built a pattern in Inkscape and cut the leather.

Using the “pattern on path” plugin I was able to get the holes where I wanted them pretty easily. This time around I think the holes are too big. I am not sure if I will be able to waterproof the flask or not with just beeswax. The flask still needs to dry before I apply the wax. I do like where this is going.

Update:

I let the flask dry completely and removed all the beans I used to form the flask. I melted 1b of beeswax in a double boiler and submersed the flask until it stopped bubbling. I removed the flask and poured out all the wax. After it cooled completely I poured molten wax inside and sloshed it around. I think I used too much as it softened up the seems and starting running out. I poured the wax out again and let it cool completely one more time. Afterwards I poured in about 3 tbs of molten wax and made sure it got to the seems and then poured out the excess. Once it had cooled completely again I filled it with water. So far so good. Going to do a 48 hour test now.

Finished flask with wax

Finished flask with wax

Posted in Laser, Leather | Leave a comment

The Robotic Minion Starter Kit (Arduino Compatible) is now for sale

Make cool stuff faster with this Arduino Compatible with it’s own screen and enclosure.

Buy them on tindie.com now.

Posted in Kickstarter, Open Source Hardware | Leave a comment

Desktop Catapult now on tindie, Instructables and Thingiverse

I’ve been working on a laser cut kit for a small trebuchet. I have it working how I wanted and I have posted the files to my favorite sites for that sort of thing.

There is also a video of it in action.

 

 

Posted in Etsy, Instructables, Laser, tindie | Leave a comment

Laser Cut Yuletide Earrings

I  know a couple of ladies who might like a pair of Christmas earrings. It took me about an hour to do the artwork in Inkscape. Then I cut them, painted with acrylic paint and sealed with clear coat spray.

You can find the files on Thingiverse: http://www.thingiverse.com/thing:35711

 

 

Posted in Etsy, Laser | Leave a comment

Lace made from leather

I’ve got some scraps of suede and a 40 watt laser. What could possibly go wrong? 3mm suede is possible to cut in the laser. There are two problems though. 1. It smell like barbequed dog hair. 2. It curls, scorches, shrinks and catches on fire as you cut.

When I was a kid in the Cub Scouts we did some leather work. I remembered that we wet the leather to soften it for some of the things we dig. So I tried soaking it in water for about a minute before cutting on it. And behold, it worked like a charm.

Still smells like barbequed dog hair. Just not as bad as before.

Now that I have 2 square inches of it, I am wondering what one does with leather lace.

Posted in Laser, Leather | Leave a comment