Author: Ray Alderman

November 17, 2017

CNC Monitoring

At AMT you are supposed to stand over your CNC machine as it is doing a job and pay attention. Is it hanging up? Is it breaking itself or the bit? It is on fire? These are all important things to know. However sometimes a job takes…forever. When cutting PCBs the job can take over an hour because I have the bit move so very, very slowly. Faster and the bit shatters into tiny little pieces of carbide all over the room. Not good. I’ve noticed for awhile that inexpensive internet webcams are available, think of it as a BabyCam for non baby owners. Turns out this little $30 wonder does a great job. When setting up the PCB to be cut I can put the camera on it, configure it to talk to my phone over the AMT network and I can be upstairs working on say a soldering job of the last PCB while the next one is being made. Very handy.

I would recommend everyone who has long CNC jobs they need to keep an eye on but don’t always want to stand over the device to try out something like this.

September 6, 2017

10W Flashlight for Mom

The original idea was to make a wide angle flashlight that my mother would use when she was out walking the dog. There are a lot of black aluminum tube flashlights out there that are very good but, most of them deal with a narrow beam. I wanted something that was neither black nor aluminum nor a tube. I was originally inspired by a youtube video: How to make a 10W light at 12V from cheap parts Lots of experimenting happened from this starting point and it wasn’t that cheap by the time we got to the end.

Which lens to use and how to mount i t and what portable power system, where all questions that needed multiple attempts to arrive at a solution. In some ways this is an incomplete project, it still needs a better battery charging system than the one I

worked out. The wood case itself was CNC cut on the big router and then I manually rounded over the edges on the router table. I went with smaller finger joints and they came out well. The cabinet pull for a handle gives it a sense of presense and mass that I try for in most of my designs. I had hoped to get the flashlight ready for Christmas one year but it was pushed over five months until Mother’s Day the next. She does love it and all reports are that Dad “borrows” it often.

July 17, 2017

High Voltage Art

I’d seen the youtube video from the Backyard Scientist guy and wanted to try that project myself.

Asking around for dead microwaves via the AMT mailing list produced more than I needed, but extra is always welcome. I was able to take the microwave apart without killing myself.

I have ideas of doing this in front of people as a science demo so I wanted a setup that was contained, portable and safe. I designed some CAD files to make a setup so that it would hopefully not kill anyone and started cutting the pieces out of plywood on the big CNC machine.

After cutting the parts out on the CNC it was a matter of glue and assembly. The idea is to have an airtight chamber so I could add CO2 at some point to cut down on the fire.

Testing was done on the workbench and lo! I was able to make sparks with the high voltage of the microwave transformer. The trick is to have the two sides with the grain and have the board wet when you are burning it. Took me awhile to figure out that a dry board is not going to happen. Doh!

It creates smoke and you want to do it in a well ventilated area.

See vine of the slow motion horizontal lightning

April 1, 2017

Adding Five Volts portable power to your project

Thanks to the growth in portable battery options we can hack those “power banks” to make portable, rechargeable five volts power sources for your own projects.

We will be be hacking and comparing two different products that output five volts – a nicely packaged and made external battery pack for older Apple stuff and a new cheapie 18650 powerbank.

Both products are basically the same. It’s a lithium-ion battery with a USB charger on the front and a boost on the back to output USB standard five volts. Some differences – the Apple power bank thing has an LED gas gauge to tell you how much charge it has and only starts outputting when you press the button. It needs that manual button press to start feeding your project the five volts. The cheapie 18650 powerbank does not need a button press – it’s switch is automatic as soon as you put a load on it, five volts are coming your way. Also the Apple power bank has some battery protection circuitry in it to stop you from draining the battery to the point it’s damaged internally. The 18650 powerbank has no such protection and you can kill the battery if you drain it all the way and then some.

Looks mighty pretty in it’s packaging, this was originally designed to be used with Apple products that had their original proprietary 30 pin socket. Now that Apple has switched to a different proprietary socket everyone had to go out and buy new powerbanks, cables, etc. Look on ebay for deals on stuff like this where time has moved on.

Let’s open up the nicer power bank. Grab a thin blade screwdriver and go to town. This is an external charger that is rare in that it has a built in USB cable, not a micro socket you plug a cord into. Designed to feed five volts into the original Apple proprietary socket it is out of favor as Apple has switched to a different proprietary socket. Still, five volts is five volts. After prying off the shell with a screwdriver we can see the output side has three different wires. five volts, ground and some strange Apple proprietary voltage.

We need to cut the old Apple socket off and solder in our own red and black to the five volts and ground connections. At that point we have a portable, rechargeable power supply that outputs five volts a the push of a button. A little hot glue for strain relief on the USB charging cable and perhaps wrapping it in electrical tape so all the connections are covered.

The cheapie 18650 setup is even easier to hack. On USB sockets the two outside wires are the power and on this one, it’s five volts and the right and ground on the left. Knowing that and still putting a bit of color on the socket so we can tell which is which we solder wires onto the exposed connections.

Finally put them all back together again and start charging them up. We now have two sources of five volts for a project, one with a manual switch and LED gas gauge and the other will give out five volts right away, no switch needed. If you need five volts for your electronics project at AMT, come talk to me as I have a small supply of both kinds of powerbank available for member projects.

March 22, 2017

Electronics Tool Rack

Having the right tools when you are puttering around making things is invaluable and having those tools near at hand is a wonderful thing. When revamping the Electronics Area and turning it into a place you are not afraid to work from the pit of darkness and despair it used to be, I noticed we didn’t have the necessary tools needed to do the job. Also we had no place to put said tools even if they where available, so I decided to m
odify the standard tool rack I developed for my workbench at home. It is a standard rack with basically vertical piece of wood between two frames, like an I beam. On each side of that vertical piece

you put a collection of PVC tubing to hold whatever you want to hold. The trick is to have an idea of the tools you want to have on it and lay those out before hand, so you know what kind of tubing and how much you need. Some #6 screws, a drill press, bandsaw and CNC up the wood bits and away you go. Rubber feet on the bottom make sure it doesn’t slide away from you as you reach for that next screwdriver. The tools selected for the rack are based on my own experience in doing electronics and detail work. Precision screwdrivers are a must but so is a regular #2 Phillips and flathead. The #2 and #1 Phillips are probably used more than anything. From there it all makes sense to have enough tools but not too many. You can go crazy on the tool rack but it starts to get too large and would take over the tabletop if you let it. Keep it basic and know what you use.

October 11, 2016

Field Guide to AMT’s Boxes of Voltage

We have different types of Boxes of Voltage for your use in the Electronics Area. While each is a Box that contains Voltage, they are each a special snowflake with special abilities to help you do that thing you want to do.

All Boxes of Voltage have a 1000mA amp meter to show you how much current your project is currently running. Over one amp and the system will still power your project but the meter itself will show dashes.

All Boxes of Voltage have spring loaded terminals in the front, Red is the positive Voltage and Black if Ground.

The Orange Acrylic Box of Voltage is a simple USB powered box of five volts variant. Plug power into the USB port on the side to feed the box a healthy supply of five volts to electrify whatever it is you need. The on/off switch is self explanatory. You can see all the electronics involved in this simple box by looking inside and seeing the electrons flow back and forth within the orange.

The Box of Many Volts is new and improved version of the venerable Box of Five Volts. Instead of just the five volts, it was decided to add a switch that allows you to choose between that number and the smaller and also popular three point three volts. Newer electronics projects are moving to lower voltages to save on power requirements and thus, the Box of Many Volts was born. Notice that the Box of Many Volts is the only battery powered, look Ma No Wires Box of Voltage we have in Electronics and thus needs to have the internal battery charged on a regular basis. The charging is simple enough, plug it into the USB port on the side and look that the charging indicator light. Red is charging, Blue is fully charged. All directions are on the box itself.

The USB Powered, Variable Box of Voltage is the newest and most complex Box of Voltage available in Electronics. You will note it has a Knob on it. This Knob is to turn and twist and adjust the voltage the box puts out, from one point five volts all the way up to over thirty volts. It’s a multiturn potentiometer and allows you to dial in the voltage you need to great precision. The Voltage meter at the top of the box will tell you what voltage are currently dialed into and the milliAmps meter is the old Box of Voltage standby. This box as well requires a USB power connection to turn on to the obvious USB port in the back. Luckily the Electronics Area has provided twenty USB power ports for the upstairs room for your general use to charge your phone or power a Box of Voltage.

When you are done using a Box of Voltage, please return it to their native location. While they are wonderful tools, self locomotion is not one of their skill sets.

June 29, 2016

A Great Night of Fusion360

Taylor Stein (@taylor_stein) a Fusion360 evangelist from Autodesk came to AMT to discuss Fusion360, how it works and what it can do for hackerspaces. We had a full house of over 20 people who had questions about Fusion360 and how best to use it for what they are doing.

Fusion360 covers a wide variety of stuff from laser cutting to CNC routing to 3D printing that there was plenty of questions to be had.

Questions from how to export STL files for 3D printing, 2D layout, parametric variable and more where covered.

Taylor showed the way he teaches layout which is to do a quick sketch of the part and don’t worry about lining the parts up. After the initial layout, go back and use constraints and dimensions to make the shape just the way you want and the relationships between the various parts stay consistent. This is a different way of layout where the separate primitives like circles, rectangles and lines are defined in relation with each other so as you change one the others move with it. For 3D modeling it makes things flow far better than having to go back and change everything after one adjustment.

We covered so much material we never really dived into the 3D CNC CAM side of things so another event was scheduled – Monday July 25th Taylor will be back to talk CNC routing and how to do 3D toolpaths and other CNC related questions.

June 19, 2016

Metalshop Vacuum Fixed

The switch went out in the metalshop vacuum and it has been replaced courtesy of the Electronics Area. Ignore the old switch and look for the new beefy toggle switch with a rubber dustproof cover that will last longer than the old one or so we can hope. Vacuum now sucks great again. On/off aluminum signage included at no extra charge.

June 17, 2016

Variable Power Supply fixed

The custom power supply in Electronics has a few basic components. An old Dell PC power supply, a bunch of wires and connectors and a DC-DC buck/boost converter module to give us variable output. That module was no longer working so I swapped it out for a new one. The culprit for the module dying? No idea. Could have been a lot of things and it’s going to stay a mystery.

Installing new module and getting the wires backwards.

When installing the new module I had a 50-50 chance of getting the wires right for the direction the knob turned to change the voltage and this time, the odds were against me. After prying the old module’s hot glued body off the side and desoldering and connecting up the new module it turns out I put the control wires in backwards and you turned it counterclockwise to increase. Thought about leaving it that way for the comedy factor and decided against that. A little wire swapping and lo! the knob works as it should.

The new module seems to be working just fine. I haven’t priced out new DC-DC buck/boost modules in awhile and it turns they are now even lower in cost, under $2 each. I ordered three as spares just to make sure for next time.

June 5, 2016

AMT Coasters

As Makers we see the potential in everything which leads to hoarding. I will admit to hoarding stuff far more than I should and one of those things I kept around longer than I need to was hardwood flooring samples. Such beautiful wood! We can make things out of this beautiful wood! And finally, years later, we did.

3 Coasters

All these coasters where made on the big CNC router out of flooring sample boards. You can get these for free or really cheap off the interwebs, the downside is you are constantly emailed and called by flooring salesman in followup. My first attempt was in doing the full AMT logo in a fine cut using a 0.9mm bit. Having such a large machine use such a small bit was funny in that Laurel and Hardy kind of way you expect. I found that I was breaking bits constantly, even when changing around the feeds and speeds. Eventually I gave up and switched over to using just a 1/8″ down cut spiral bit for engraving the top with the logo and for cutting out the coaster when done. These are less fine detailed but do have the advantage of not destroying a ten pack of bits. I used spray adhesive on the back to glue down a shelf liner backing.

That works… sorta and for a short time. Need to come up with a better solution for putting a non-stick backing on these guys. Overall I’m pleased that we still have most of them around AMT, I thought they would be gone in a few weeks but here we are months later and you can always find a coaster upstairs when you need one.
Now what to do with the box of flooring samples I still have….