Saturday, May 15, 2021

Custom-Formed Toolbox

 I have a Dodge Ram.  The rear back seat folds up to reveal some pockets, and I've had some emergency tools loosely thrown into one of these pockets.

These are awkwardly shaped, and not level.  If my tools end up greasy or dirty, I'd rather not get the carpet soiled.  Also, if I had a Craftsman set (one of those portable tool sets) that would have fit, I'd have just called it good.  Commence over-engineering a new "toolbox".

I was told about "Kydex" from one of my buddies who loves leather work.  Kydex is commonly used to make holster clips (attaching a holster to clothing) using a heat gun for forming.  So, keeping that in mind, I ordered a 24"x36" sheet of Kydex.

Now, if I were to start this over, I'd do this a little differently.  I'd go to the fabric store and by the cheapest, white-colored fabric (about a yard is all that is needed).  I'd then lay the fabric into the pocket that I'm forming to, and draw lines every where there is overlap on the fabric.  Then, I'd cut out the overlapped pieces, and I'd have my pattern to trace onto the Kydex sheet.  However, I started before I ever even thought of that, and this is process I'm going to walk through.

First, I needed to get the shape of the base of that pocket.  I used a sheet of paper and traced the corners to generate a base template.

With the base template, I could position that on the Kydex sheet and trace it on.  I'm going to use a silver-colored sharpie for contrast.  Placing this required measuring the height of the tool box to get it with the length of the sides as the distance away from the edges of the sheet.

The hardest part of all of this is that the compound curves are going to be difficult to form.  I threw some lines coming as tangents from those curves for some saw lines, and measured the height away along those lines.  Using those markings, I drew another line around the outside - my outside cut line.

What I was left with as a pattern that I could then cut out.

Those compound corners were going to bite me - I knew that, so I cut along those lines I'd used earlier to get the outside cut line in place.  This would allow me to form the Kydex around those curves and corners.

Next up was to start forming the box.  I lined the pocket with aluminum foil.  This would protect the carpet in those pockets from heat as everything was formed.

Now, I broke out the heat gun, and heated along the original pattern lines until the sides could be bent up.  I worked it a few times until I could drop it into the pocket and press the Kydex against the shape that it was being fit to.  This was repeated numerous times until I was satisfied with the resulting shape.

With the shape set, it was a little flimsy - those sides were all loose-goosey.  It was time to start "welding" it up.  Mind you, I'm a terrible welder.  But, hey, this is an experiment in futility, so, I jumped in.  I did learn that my plastic welding is worse.  But, it was adequate.  I would weld some seams on the plastic about one inch in length, and slowly work my way along the entire seam.  When I was satisfied, I'd use the heat gun and re-form the newly-joined sides back to the cavity.

This was a long process - a lot of repetition of plastic welding, heat gun forming, and inserting new pieces of Kydex to fill any gaps and holes.

The more I added, the stiffer this box became.  There were a few times the welds snapped.  I started even doing the "stack of dimes" with the plastic welder, and then I'd run over it dragging it to clean it up and get it strong enough.  (Again, I'd only do about an inch at a time so that what I'd just welded didn't set until I had run the clean up drag stroke.)  It was a lot of wash, rinse, repeat, until I had the base done.  While I was there, I folded an area to hold a breaker bar, and "welded up" a bracket for the handle :

Then, being tired, I just dumped all of the tools back in.

I need to make some separators and organizers, layering the tools and giving each one a place to be.  Then, I can call it good.

Saturday, May 1, 2021

In Flight - Quad Lifts Off

There are times that you find yourself in boring, remote meetings.  And there are times that you remember the old quad copter you built ages ago.  And then there are times you find yourself addressing a few issues.  After I put it together and configured it, I had a few issues.  I could never get it to lift off, even with launch control.  Also, after a few attempts, I didn't have any camera for FPV flying.  I had the OSD, but I did not have any video feed other than a black OSD screen.

First, I set to figuring out the launch.  Usually, it's because either a propeller is spinning the wrong direction, or the front, top, or right side is not set right.  It took a few iterations to figure it out (in the Betaflight Configurator, it would roll the opposite direction, but the pitch was good).  With that set, and without a video feed, I was able to get it airborne and do some simple flying.

Next up was to tackle the camera feed.  Knowing I had OSD on a black screen, that eliminated the transmitter, and the flight controller that added the OSD.

I bypassed the OSD plugs on the flight controller just to make sure it wasn't the flight controller and had just a black screen, so I knew this was the camera.

I plugged in another brand new camera, just to make sure it was good - no dice.

That told me it was a potential problem with wiring, but I had to make sure.  I contacted RunCam, and they sent me a quick "picture" of how to wire so I could build a test rig.  The camera I had came with a few cables, so I took the spare, and cut into it.  I used a plug for the 4S battery that powers the whole thing.  Here's how, using only the three essential wires (the negative power connects to both the camera and the cable) :
  • The battery negative (RunCam called this "ground" - it's really not) connects to the camera ground and the outside of the RCA/Composite cable
  • The battery positive connects to the 5V input on the camera (it accepts 5V to 36V, so the 14V of the battery was sufficient)
  • The "video" cable from the camera connects to the center of the RCA/composite male plug
A picture is worth a thousand words, right?

After a quick build of the cable, I had my rig, and hooked the camera up to the video output.  I used my flight battery to power it up, turned on the monitor.... and I had video.  I checked both the old camera, and the new (the old was simply a little blurry, so I could adjust it while I was there), both being successful.

That told me my problem was really in either the flight device not receiving video, or the camera was not getting enough power.  I took it apart, and I found the 5V line feeding the camera was coming from.....

.... the 5V pin on the video transmitter?  Huh?  What was I even thinking?

I measured the voltage and found 4.7V.  The flight controller had a 10V output, so I rewired the video camera to the 10V, and sure enough, I had video and OSD together.

Headed out to test it, and this thing is extremely sensitive and responsive.  This is wicked fast and maneuverable.  I need to get to open spaces to play with this.