[buildingwithidlehands]

3D Printed Seat Back

I finished 3D printing and installed the new seat back on my wheelchair rugby chair. One thing that frequently would happen when I played, is that whenever I leaned over, the side of my abdomen would rub my tire. So in this seat back, I needed lateral supports for trunk stability, anyway, so I figured I would just extend them down below where the tire would rub.

A lot of times, with 3D printing, you're limited based on the size of the print platform, forcing you to often need to print a larger part in separate pieces and glue them together (In this case, temporarily with duct tape). Sometimes building stuff also requires a bit of origami, as was the case with this part of the seat. If the chair were facing away from my dog, these four pieces go together to form the lower back of the seat, then the seat folds 90 degrees at the tape across the middle, forming part of the seat where the seat cushion rests. The tabs at the bottom of the wing-looking things, fold 90°, and then the wings themselves fold in forming the clothing guards between me and the spokes.

"Did you get all that, Sadie?"

"It looks like a bat to me. A very flat bat. A flatbat."

{sigh}

"Flatbat."

My aide over the past 10 years, Sahid, has been with me through thick and thin ( https://bit.ly/2KnisyA ) and has become like a brother to me. This morning, he confessed that he believed I had a 30% chance of successfully making it through practice without it falling apart. I must mention that his calculation of the odds was completely unsolicited. He offered it up, like, five minutes after I woke up. I'm an optimist and putting it at 75%. If it ends up being 30%, I’ll have to tape it back together, and lie to Sahid about it, of course.

Even without trying out the seat yet, I already know I'll make modifications. But this will be my most ambitious printing project ever. The current version, is four sections high, and probably about 3 feet tall. My printer can't print anything higher than 8 inches, which is why I had to do it in sections. So here's what I'm gonna do… It seems the only thing limiting my height on the printer, is the length of the rods on either side and the length of the cables. I'm going to attempt to modify my printer such that it will be able to print a single piece that is 3 feet high. If successful, this will be my moon landing.

[buildingwithidlehands]

Legalizing an old rugby chair.

So, I got back into playing wheelchair rugby, after a nine or 10 year hiatus. I had a rugby chair from the last time I played, that was no longer legal to use in official games. The front end of the chair is supposed to have a picker (bumper) that conforms to a certain shape and height. My Eagle Sports chair is probably from the late 90s or early aughts.

I'll be applying for a CAF grant to get a new chair, but they don't open for applications until the fall. In the meantime, I've had the goal of making my illegal chair legal to play a game with. The only concerns that I saw were the picker and the anti-tip wheel in the back. Modern chairs have two wheels in the back and I wasn't sure if there was a rule about that.

I mocked up what I wanted to have done in 3D, and handed it and the chair off to a local welder.

Here's how it came back. A new footplate and new picker. The welder did a great job and only charged me $150. The real test was during the DC rugby tournament a few months back. They do chair checks prior to every game, and I lined up to have my chair looked at. The first thing they did was measure the front end using a special tool. The front end passed. The referee looked at the single back wheel and wasn't sure if it was legal. He deferred to another referee who said the single wheel is legal in the United States, but illegal in international play. I told them both they didn't have to worry about me playing internationally. Long story short, it passed and is now a legal rugby chair.

Don't ask me how I got a legal picker to put on.

But wait! I'm not finished. There's still the seat. I happen to have scoliosis from a hip surgery about six years ago, so I can't sit up straight in my rugby chair unless I have lateral supports. So I 3D printed a couple of lateral supports and Velcroed them to the nylon seat. The problem I've had is that they tend to move during a game, so I decided to take my modifications one step further.

I decided to 3D print a new seat back out of TPU, a kind of rubber. The seat is so tall that I had it printed in sections, and it's so wide, that it would not fit on my printer unless I curved it on the build plate. The benefit of working with rubber, is that it can be stretched into a different position after printing. This is the second section of the seat, with the lateral supports. It took about 32 hours to print this entire section.

Here are the first two sections on the chair (temporarily held together by duct tape). If the seat works well at our next practice on Tuesday, I'll glue the sections together with superglue. The sections connect with a tongue-and-groove. If there are changes that need made, it's fortunate I've printed it in sections. Two more sections need to be finished and installed, then I need to print some clothing guards on either side of the seat (to keep my pants outta my spokes).

Back view. Rugby players generally use a chest strap (like a weight belt) for trunk stability. Sometimes the strap ends up sliding up during play, so I printed the back with a tab on either side, for the chest strap to slide up under.

"Is that a Jon Campbell-brand seat back?"

"Why, yes. Yes, it is"

[buildingwithidlehands]

My new and improved footplate.  With the plate I did a few months back, I noticed my feet would occasionally slip when going over bumpy terrain, so this new one has cutouts for some rubber pieces that I had 3D printed. I’ve counter-sinked the screw holes and had it anodized in as close to a titanium color as they could do.

[buildingwithidlehands]

I’m back

It’s been many months since I last posted anything. There’s no particular reason why, because it’s not like I stopped building things. I’ve built many things over the months and will resume posting interesting ones.

[buildingwithidlehands]

Custom Wheelchair Foot Plate

The footplate on my wheelchair has always been too small and something I've been meaning to fix for years. I discovered a website called sculpteo.com, where you can upload a design and they can laser cut it out of a variety of materials.

Yeah, it's got my name on it. When you make your own parts, you can put your name on them. Don't judge me.

I got it about a week ago, and took it to the local bike shop to have the holes countersunk so the heads of the screws will be flush.

Flush!

I then took it to Alexandria metal finishers and had it anodized (a hardened protective coating on the surface). I was hoping they would be able to get it close to looking like the titanium finish on my chair. Anodizing is a tricky process, so it's pretty hard to color match. Even so, the finish they put on it comes pretty close.

And here's what it looks like the chair.

If someone ever got a hold of my chair, they could use my footplate as a stencil to sign my name and commit check fraud.

Yeah, but what does my last name look like? Aha!

[buildingwithidlehands]

This is my latest creation – a bracket for holding two of my iPhone control buttons. When I'm driving, I use one hand for gas and brake and the other to steer. That leaves me a hand short for controlling music on my phone or bringing up Siri. I found these nifty Bluetooth control buttons by Satechi. They were about $25 each and one of them controls the music app, and the other serves as a home button.

Creating the bracket was difficult for a couple of reasons. First off, it had to fit into the steering wheel in my car, which wasn't something I could bring up to my apartment to get a bunch of measurements. Second, there is not a straight line on my steering wheel. The steering wheel itself is round and the center part is contoured inward. I began by getting some measurements and taking a couple of pictures. I placed the ruler of my calipers in the picture so that I could bring it into my CAD application and get a close approximation of the size, but most importantly, the shape.

When I set out to make this bracket, I originally only had one button in mind. But once I realized I had room for two buttons, I changed my design. The great thing about designing in CAD and 3D printing, compared to working with raw materials, is that, with each iteration, I can start exactly from where I left off with the previous one. For example, if I were trying to design this out of wood, I would carve version 1, test it to see what changes I needed to make, and then start making those changes by carving some more. It's not so bad if I'm just removing material each iteration, but if the shape is gradually changing as well, I would have to start out with a new block of wood each time.

With CAD and 3D printing, I design on computer and print off a version. I test it out, and no matter what changes I need to make, I can go into my computer and make changes to the exact version I had tried. The other thing that's great about CAD and 3D printing is that once I'm happy with the design, I can print off as many as I want or send the file off to be printed in other materials. I could even send the file to a CNC manufacturer and have it milled from a block of aluminum. Also, if I ever decide to put anything in the same space on the other side of the steering wheel, I can simply flip the design in my CAD application and then print off a mirror copy.

Who knows how long this would've taken me if I were able-bodied and had to make it by hand. This one took me about two days, 18 iterations, and many, many trips out to the car. Once I reached a point where I was satisfied with it, I uploaded my design to http://shapeways.com and had a 3D printed in a heavier plastic.

[buildingwithidlehands]

Zenith radio modification – part three

Last night I printed and installed the gear system in the back that will turn the dial when the knob on the front is turned. I also soldered a couple wires to the original buttons and found that they still function and I'll be able to use them the way that I want to. Right now, the gears aren't completely smooth, as one of them is rubbing a bit and needs a spacer.

The smallest gear in the back is connected to the knob in front. The ratio of the gearing is set up so that, two turns of the knob will turn the dial once.

The next gear down is connected to a stepper motor. This motor will turn the dial when one of the radio preset buttons is pressed on the front.

The big gear is connected to something called a rotary encoder. The rotary encoder will send back to the exact position that the dial is in, in order to know what station or audio to play.

Control of the motor and reading of the rotary encoder will happen in an arduino board, which is just a type of hobbyist microprocessing board. That's what I plan to do next.

Once I have that done, I'll hook it all up to a raspberry pi, which is another hobbyist board, but more like a small llinux-based computer than the Arduino board. When it comes time to integrating it with Internet radio and Pandora, that's where all that will happen.

For the most part, I pretty much have a plan in my head, but in a lot of ways I’m just kind of winging it.

These are the parts for the knob. The knob itself is off the original radio. I ordered a D shaped shaft, collar, and bearing, and printed the gear and the bracket that mounts it to the radio.

Here's what it looks like assembled.

I had to post a picture of this, because I thought their slogan was pretty funny. *Carefully* made shaft collars and couplings. I would hope so. That's kind of like saying, " Sufficiently precision-made shaft collars and couplings"

[buildingwithidlehands]

Zenith radio modification – part two

I managed to make a lot of progress with my radio project this weekend. For those of you who haven't been following my past couple of posts, I am renovating my 1942 zenith radio. On Thursday and Friday, I molded some clear plastic to put in place of the missing glass. This weekend I designed a frame and I installed a Phillips Hue light strip. I managed to get to a good stopping point for once, and can move on to phase 2 next weekend. Here are the various steps I took to install the lights:

I designed the frame to have a slot to hold the light strip in place. The light strip is about 6 feet long, which is about 4 feet longer than I needed. Fortunately, they designed it with segments every foot or so that can be cut.

This is roughly how it will look when it's done. Right now, duct tape is holding the plastic face in place, and the dial face is just resting on the table underneath everything.

[buildingwithidlehands]

Modifying my 1940′s Zenith radio – part one

I have an antique Zenith radio from the 1940s that my dad shortened and modified for me to use as a TV stand in my living room. I got the radio 7 years ago, back before I got involved with 3-D printing and electronics,and had always wished it had the front glass for the dial. Since I know how to do a few things now and I have a 3-D printer, I set out to mold a clear piece of plastic for the front face. Here are the steps that I took:

Sadie's looking at me like, "dad, when the hell are we going to put a piece of glass on this radio??"

The face has an unusual shape to it and I did a bunch of measuring and took a bunch of photos, but I wanted to be confident that I had the right shape before committing a lot of plastic to make a mold, so I printed a flat frame to make sure I had the right size and fit. My printer only allows me to print objects 140 mm³. The width of the face was about 190 mm, so I had to divide up the frame and ultimately the mold into four pieces. If you look closely you'll see that I used a keystone shape to lock the pieces together.

This is what the mold looked like before I divided it up into pieces.

After printing, I screwed the mold down onto a board.

I placed the mold into my toaster oven with the plastic on top. I put the paper towel between the plastic and the mold for two reasons. First off, I wanted to try to insulate the mold as much as possible from the heat of the oven. I set the oven to 275°, which is the melting point of the clear plastic. I'm not sure what the melting point of the PLA plastic that I use in my printer is, but in tests, it softened up at 275°. The paper towel also serves to keep the plastic from sticking to the mold. The second reason for the paper towel, was because, If you look at the mold, the surface isn't smooth. Due to the way 3D printers print one layer at a time, round surfaces tend to have a little bit of a stair step. I wanted to make sure that that stair step would not be pressed into the clear plastic.

After taking the mold and the clear plastic out of the oven, I pressed them down onto the frame of the radio.

After taking the mold and the clear plastic out of the oven, I pressed them down onto the frame of the radio.

The finished face looks like this. It turned out the way that I wanted it to, but I'm not ready to put it back together yet. My original plan was also to install a Phillips Hue light strip around the outside frame so that I could control it remotely along with my living room lights.

Like with many projects I work on, sometimes there's a lot of waiting for one thing or another, which gives me time to think. I got to thinking that I want to make the radio dial and the buttons work again. So after I finish the lights, my plan is to rig up the radio with bluetooth so that it can play music off my phone or my computer, as well as Internet radio and maybe even a couple local radio stations that I listen to.

To think, some family likely sat in front of this thing 70 years ago, listening to radio programs, never thinking what would ever happen to this old radio.

[buildingwithidlehands]

Adaptive Equipment: Setting up two trackballs and a keypad using ControllerMate

I thought that my setup could be useful to others, so I’ve created an installation guide with links to the necessary hardware and software.

For starters, you’ll need Mac in order to make this work. I’m not familiar with a PC equivalent, but Macroworks might give you some of the keypad functionality.  

To create the setup you see in the video above, the first thing you'll need to do is order the proper hardware. It's very important to get the devices listed below as the presets I've created are for these devices only. The ControllerMate software is capable of controlling a variety of devices, including other trackballs, but for the presets I've included, you'll need these specific devices to make them work.

Kensington Expert Mouse Trackball This will be used as the primary trackball on your computer.

Kensington Orbit Optical Trackball This trackball will be used for scrolling only.

X-Keys XK-24 This keypad will be programmed with convenient keyboard shortcuts of your choosing.

Part one: Installing the driver software

It needs to be stressed that you should not install the Kensington software for either of the Kensington trackballs. It will interfere with the ControllerMate software and you won't be able to use the devices the way that you want. If the Kensington software is already installed, use Kensington's uninstaller application to remove it and restart before continuing.

The first thing you want to do is go to ControllerMate's official site at http://www.orderedbytes.com/controllermate/ and click the button to purchase. There is a free version available, however the free version is limited in functionality and won't let us do what we want with all of the devices.

After you've purchased and downloaded the software, double-click on the ControllerMate.dmg file, and then from there double-click on the ControllerMate installer package. This will install ControllerMate on your computer. You'll need to restart your computer in order for ControllerMate to control your devices.

After you’ve installed the application and restarted your computer, open the ControllerMate application from your Applications folder. You should be prompted the first time you open the application to register. You should have been emailed a product key to enter into the registration fields.

If you are not prompted to register when you open the application, go up to the ControllerMate application menu on the top left and select Register from the drop-down menu.

  Part two: Installing the presets

Now that you’ve installed the ControllerMate application, it's time to download and install the presets that I've created. Go to http://bit.ly/trackball_files and click on the ControllerMate Presets.zip file to download.

Once downloaded, double-click the zip file and open up the ControllerMate Presets folder.

Inside you'll see the three preset files that I've created - one for each device.  You can install any one of these or all three, depending on what functionality you want.

  Click-Lock (Drag)

If you have difficulty holding down one of the trackball buttons while you drag your cursor across the screen, click-lock will help a great deal. The way it works is, you have one button set up for clicking as usual, and you assign another button with the click lock. When you press that button, it will click and hold until you press any of the other buttons again.

If you would like to have one of the buttons on the Kensington Expert Mouse Trackball have a click-lock (drag) when clicked, double-click on the Kensington Expert Mouse Trackball Click Lock.cmate file to install the proper preset. You will be taken to a dialog asking you if you are sure you want to import the preset. Click import.

After importing, you will see a group called "Imported from Kensington Expert Mouse Trackball Click Lock”. To activate this preset make sure the checkbox to the left is checked. Click the triangles to the left to expand all of the groups. You'll see several programming pages, one for each button. The one that you check will be the button on the Expert Trackball that has the click lock behavior. It only works with one button selected as the click lock at a time.

Note: The click lock behavior only works when the ControllerMate application is closed. The developer has done this in case a user loses control of their mouse due to improperly programming a page in ControllerMate. It's not something you'll need to worry about with the presets I've included. Just be aware, that the click lock won't happen immediately when you click the checkbox, but will when you quit out of ControllerMate.

Using a second trackball to scroll

I have found that the scroll wheel on the Kensington Expert Mouse Trackball isn't the quickest or most efficient way to scroll, especially when compared to multitouch trackpads. So I've added a second trackball – a Kensington Orbit – that I use for scrolling. The second trackball can be programmed to do anything, for example in my CAD application, I use it to rotate 3D models.

I've created a preset that will give you the scrolling behavior to your Orbit trackball. In the ControllerMate Presets folder, double-click on "Kensington Orbit Scroll.cmate”. You will be taken to a dialog asking you if you sure you want to import the preset. Click import.

Once imported, simply check the checkbox next to “Imported from Kensington Orbit Scroll.cmate”. That will give you scrolling behavior on the Orbit trackball. As long as that preset is checked, that trackball will be used exclusively for scrolling and cannot be used to move the mouse cursor.

Setting up keyboard shortcuts with X-Keys 

If you would like to set up an X-Keys XK-24 with keyboard shortcuts, I've included a preset that has a template you can work from.

Double-click on the “X-Keys 24.cmate” file in the ControllerMate Presets folder. You will be taken to a dialog asking you if you sure you want to import the preset. Click import.

Once imported, check the checkbox next to "Imported from X-Keys-24.cmate”.

Then to begin assigning keyboard shortcuts, click on "Global Page" inside the Global group.

That will open up a template programming page with a node for each button on the keypad. To make a button shortcut assignment, click on the node underneath the device node labeled "X keys XK-24 Button #1” (pictured below).

That will open the properties inspector where you can record keystrokes. Under the column "When turned ON:” you'll see a button that says “Capture".

Click the Capture button and then type COMMAND - SHIFT - 4. Then click STOP.

The inspector should now look like this, with the keys you pressed down and released. 

Now when you press the Button #1 on the keypad, it should push COMMAND - SHIFT - 4.

To clear the buttons that you assigned, press the Clear button.

Repeat with the other button nodes to assign shortcuts to the other buttons.

ControllerMate is a powerful application that you can do a lot with. You can create different key layouts for different applications. It's too much to go into here, so I recommend you take a look at their website. The developer of the application is really good about providing support.

    I hope that this guide was useful. If you have any comments or questions, please leave them below.

[buildingwithidlehands]

In this final video of the Cyclometer series, I install the cyclometer that I modified onto my wheelchair.

Links in this video:

Cyclometer Hack https://www.youtube.com/watch?v=_6jb6tZrB5M

Sadie's YouTube channel https://www.youtube.com/user/sadiecampbell

[buildingwithidlehands]

Picking up where I left off in my previous series of cyclometer hacking videos, I zip tie the modified cyclometer to a bracket that I 3-D printed.

Links from the video:

Tenodesis explained by J. Glen House, MD https://www.youtube.com/watch?v=aaVPG97Q1hk

Sadie’s YouTube Channel https://www.youtube.com/user/sadiecampbell

[buildingwithidlehands]

In this video I put together a USB drive enclosure for my SATA hard drive.

Tenodesis explained by J. Glen House, MD https://www.youtube.com/watch?v=aaVPG97Q1hk

Sadie’s YouTube Channel https://www.youtube.com/user/sadiecampbell

[buildingwithidlehands]

Part 3 of 3. In this video I begin taking apart a cycling odometer that I need to modify to use a rechargeable battery.

Links from the video:

Sadie’s YouTube Channel https://www.youtube.com/user/sadiecampbell

[buildingwithidlehands]

Part 1 of 3. In this video I begin taking apart a cycling odometer that I need to modify to use a rechargeable battery.

Links from the video:

Tenodesis explained by J. Glen House, MD https://www.youtube.com/watch?v=aaVPG97Q1hk

Sadie’s YouTube Channel https://www.youtube.com/user/sadiecampbell

[buildingwithidlehands]

Part 1 of 3. In this video I begin taking apart a cycling odometer that I need to modify to use a rechargeable battery.

Links from the video:

Tenodesis explained by J. Glen House, MD https://www.youtube.com/watch?v=aaVPG97Q1hk

Sadie’s YouTube Channel https://www.youtube.com/user/sadiecampbell

[buildingwithidlehands]

Part three of an epic three-part series in which I assemble a picture frame that I purchased to house a ridiculous caricature of me and my dog.

Sadie’s YouTube Channel https://www.youtube.com/user/sadiecampbell