Corbin's Treehouse - Corbin Dunn, Santa Cruz, CA
Plug Bug

Archive for 2014

Red Rocks climbing

Did some climbing in Red Rocks, Nevada last weekend. This is more of a record and reminder for myself. Last time I was there was in 2005 back when I was a strong 5.11 climber. I don’t climb very often right now, and I felt rather nervous about doing much of anything.


Costanza and her dog Douglas came with me. The first day we arrived around noon and stopped at the first pullout. I didn’t bring a guidebook (mistake) hoping I could piece it together from the Mountain Project website. I was targeting Panty Wall, but it was way too busy. We walked/hiked around a lot, which was a ton of fun in itself. We hiked towards the left (second pullout area) and saw some people climbing at Tsunami Wall:


A young guy was doing the 5.12s. I debated doing the 5.7 trad climb…but I was just too nervous and wanted to work with Costanza on lead belaying first. We headed back towards Panty Wall and stumbled upon Amusement Park; I didn’t know what it was at the time, since we lacked a book, but it didn’t look too hard and I could setup a top rope on one of the last routes on the right to give me confidence:


I set it up as a top and it was super easy for me. After Costanza gave it a good try I pulled the rope and led all of them for fun and practice.

The next day (Thanksgiving) it was again packed. We stopped at the first pullout again briefly; packed as usual at about 11am. We went to the second pullout and got out to hike around. I wanted to go to Magic Bus, as I recall doing routes there in 2005 with Jason. Unfortunately Douglass couldn’t make it up there, or the scrambling back behind it to check out other routes. No problem, so we went on to the Sandstone Quarry parking lot area. We hiked the short walk into the gap that I think is Front Corridor; it was packed, and two dogs where there off leash, so we looked for some more areas. The Wake Up Wall, which is to the left of the wash and a bit north west was recommended. We saw it from a short distance, and it looked packed. Plus, the easiest was 5.9..and I wasn’t sure I wanted to lead 9’s yet. We hiked in the wash “Turtlehead Peak” trail (according to the map) and found some routes on a wall. It clearly hasn’t been climbed in a while (or not much at all), and I setup a top rope pretty easily. The rope dragged over the edge because I forgot my webbing to extend it, but it was lots of fun! I’d say 10d to 11ish in rating. I can’t seem to find this area on the Mountain Project; I see the rock on the map, but nothing marked. I’d say it is the rock to the west and slightly south of Bull Market. Here’s a picture I took;


The day after Thanksgiving we got up early and got there about 10am. This was early enough to get any parking (although it got super busy again later in the day). Panty Wall was already busy, but The Hamlet was empty and seemed easy to top rope for the “Lower Tier”:


I don’t know what routes we really did; they were all 5.7 to 5.8, although I picked out some 5.10 variation moves that were pretty fun on the flat face like portion seem in the middle of the above photo (to the left of the large crack).

After got busy, so we left and went to a later pullout by Willow Springs…TODO: look up the name of this area (I have it on my phone but can’t find it on Mountain Project):


I did the easy 5.7? trad lead. One bolt on the bottom, and some old slings on top tied off a rock for rappelling.

EV Page of Shame: Drax in a Lexus at the Aria Hotel in Vegas

UPDATE: Thank you Aria hotel! They are going to update their signage and start towing offenders. I just talked with someone from the security team and they are on top of this. They are also going to fix the broken charger. Excellent! They handled this very well, and I’d be happy to stay with them the next time I’m in Vegas.

(Still, I think Drax and others should not park in these spots, so I’m leaving the post up).


Aria Hotel in Las Vegas: You provided four EV charging spots but failed to enforce the rules, and allowed three non EV cars to park in them:


First and foremost I blame the people who ignorantly and rudely parked in these spots; especially the Lexus with the California license plate “IM DRAX“:


That Lexus belongs to this wonderful person, Drax:
Screen Shot 2014-11-30 at 9.51.04 AM.png

Lots of awesome tattoos and guns:

Screen Shot 2014-11-30 at 9.53.38 AM.png

His instagram account shows pictures of him at the casinos as he moved to Vegas about four months ago to become a professional poker player. Drax is even hip enough to have a reddit account, and lets us know that he weighs 190lbs (follow the link for some sexy underwear pictures).

Drax, I’m glad you are making it big as a poker player in Sin City, but please walk a little distance and don’t take up an EV parking spot, unless that Lexus is actually plugged in. Also visit Drax on YouTube, and GooglePlus . Now, the fourth car in the green parking spots (not seen) is a Model S:

But the last Chargepoint station was broken, and the Model S couldn’t reach to the other working station that did work due to it being “ICE’ed”.

Drax, welcome to the EV Page of Shame!

Electric Bug: Running Again!

So, I got my new rebuilt transmission from MOFOCO. I put it back in the car and buttoned up the rear end entirely. I then attached the shifter…but, it wasn’t shifting! So, I posted on and the guys there said something might be wrong w/the nosecone setup. I had to drop the transmission/motor combo again. This time I decided to make a better cradle for it:


These pictures are mainly for my future reference so i can remember how it goes. The strap holds it on pretty well.


I popped the nosecone off and it was definitely shifted into a gear. It didn’t seem like it was shifted into two gears at the same time…but it definitely wasn’t working before. I pulled the three things below so they were all aligned, and put the nosecone back on. I could then shift it by hand, as I should have been able to do in the first place. Excellent!


Then it went back in the bug…and it seemed to be doing okay. I put it all back together…and did a quick test drive. Success! Back to electric driving. I’ve been missing it.

Adafruit CC3000 + Webduino = Arduino Web Server over Wifi

Adafruit has a CC3000 breakpoint board for $35 on their site. Rather expensive, considering the chip should be $10, but it adds some nice features and they wrote a library for it.

Cut to the chase: for a rather full featured Arduino web server with the CC3000 chip, check out my port of Webduino CC3000 on my GitHub page. REQUIRES my forked version of Adafruit_CC3000


Longer story: I want to add Wifi support to my LED cyr wheel. My goal is to be able to wirelessly control it from an iOS device (iPhone or iPad). I also want to be able to update my LED Pattern Sequence files from my desktop Mac computer. Right now, I manually put them on an SD card, but it seems like I could skip that step and send it over wirelessly. Short range wireless connections on iOS are difficult; bluetooth would be ideal, but has stupid rules to be able to use the API/hardware. Bluetooth LE is newish and supported by the later iOS devices and computers, but my Mac doesn’t support it. Stupidly, my friend Jason gave me the solution for that: just by a dongle. Oh yeah… but anyways, I’m going to try Wifi first.

I now realize the CC3000 chip isn’t ideal because it can’t create an ad-hoc wifi network. It can only join one. That means I have to bring a wireless router with me for circus jobs and have the phone/wheel on the same network. Or setup internet sharing on my phone and connect to the iPhone wireless network from the wheel (that does work, and is okay for now). Bluetooth LE may have been better…but I’m not sure if I can control multiple wheels at the same time (another goal) and synchronize them, as I think bluetooth is a 1-to-1 connection (I could be wrong, I don’t know). I also heard the newer CC3100 chip(or 3200) might have more features; maybe ad-hoc. I should investigate if I ever make my own PCB board that has it on it.

So, using the CC3000 and wifi. I quickly realized I have to make a web server in the wheel. I came up to speed on some new(hah) “protocols” like REST, which seem to be all the rage today. I like stateless, so it seems good. I found a few REST solutions, including aREST (Arduino-REST) that uses CC3000, but it isn’t very flexible.

I then ran across Webduino; it is a few years old, but looks awesome. You can plug in your own handlers for URLs, which is a very simple way to implement REST. So, I ported it over to use Adafruit’s CC3000 breakout board. Check it out: Webduino CC3000

UPDATE: I have been constantly working on this and made Webduino and CC3000 work together better by having a simple state machine. REQUIRES my forked version of Adafruit_CC3000

LED Cyr Wheel v2: Custom PCB

I finished designing a custom PCB for my LED cyr wheel. It simply combines all the chips I use into one board. Ideally I would eliminate all of the other boards except the Teensy, but I’m not so good at SMD soldering yet.

I designed it in Eagle:

Screen Shot 2014-10-10 at 9.20.18 AM.png

And I’ll be printing it with OSH Park based on advice from my friend Spencer.

This things should be awesome! It’ll be my first PCB, so i’m crossing my fingers that I did everything right.

Screen Shot 2014-10-10 at 9.22.18 AM.png

SD Card errors with Arduino / Teensy 3.0

With my LED cyr wheel I kept getting random errors in reading data from my SD card with Ardunio code. Sometimes init would fail, even at half speed. Most often I would get corrupted data, or not be able to read the filenames. Worse, it would start to read and then fail. Searching around, I found it could be one of the following problems:

* Bad SD card (I tried a few of them)
* Improperly formatted SD Card (I used the official SD Card Formatter from SD: and it still failed)
* Floating CS (Chip Select / Slave Select) pin. I made sure I had the Chip Select pin was correct, and it was. This can be set to anything you want as long as it is wired properly and passed to the initializers.
* Incorrect voltage for the SD Card; it needs 3.3v. Now…long story short: this was the problem, but I thought it wasn’t because the SD Card Adapter from PJRC has an onboard voltage regulator.

I poked through the SdFat library quite a bit adding in debug logs and couldn’t figure it out.

Finally, I poked at the voltage that the SD Card Adapter was reading; it had a 5v input and the regulator was outputting about about 3.0something volts. I thought this was okay…but later I came back to it, and wired the 3.3v directly from the teensy output to it. Then stuff started working!

So: be warned. The PJRC Teensy SD Card Adapter needs a separate 3.3v input (and solder together the 3v joint). The onboard regulator doesn’t work well enough!

UPDATE: I’m not 100% confident this was the problem. Dealing with the SD card has been a nightmare due to read errors and inconsistency. I could reproduce the corrupt data problem on my breadboard and with my physical hardware, which is why I felt like the voltage was the problem. However, in my LED wheel I still had issues, and it seemed to be due to wire length and size. I’m now using 22 gauge wires with shielding, and slightly shorter. It seems to work so far.

UPDATE 2: Maybe I am just an idiot; after re-wiring a bunch, I realized what CS pin I thought I was using may not have been right! That may have been my problem all along..

Firewood Hutch

An oak tree fell down at the end of last winter and I ended up with a lot of great firewood. I saved a few pieces for woodworking (we’ll see how those turn out), but the rest is going to heat my house. I needed a convenient place to store the firewood, and I originally was going to turn my back door cement area into a covered firewood area…but Costanza and my friend Mark convinced me it was a bad idea (it would block too much light into my house). So, I designed a little firewood hutch that would go under my bathroom window.

The final result, packed to the brim with firewood:


I had to pour some concrete posts, as wood+ground contact creates rot and termite infestations:



I wanted the floor to be level with my existing concrete floor; I had to dig out a bit of earth and set a four by four on top of the concrete pillars, along with a hacked up support for them embedded in the concrete:


Simple roof construction, 4x4s with 2×4 roofing:


3/4″ ply on top (leftover from Burning Man — I had used the plywood as flooring for cyr wheel), and then painted/stained to match the house (I also did all the back side, which needed it!):


Then, roofed (tarpaper + shingles):


LED Cyr Wheel on Stage

Some pictures of my work with Velocity Circus at an event for UCSF



Photos by Hiromi Yoshida, Courtesy of Gregangelo & Velocity Arts & Entertainment

Photography: LED Cyr Wheel v2 Self Portraits

Self Portraits, Corbin Dunn, LED Cyr Wheel v2, September 11, 2014. Canon 5d, a timer of 10 exposures manually set for a specific aperture and shutter speed.






Pattern Test


Single Pattern Test


Final drive ratio in an electric conversion car

So, I’m getting a new transmission for my VW bug (number 3), and probably buying it from What drive ratio should I get? They can do a few different options.

My bug is/was currently running the stock stuff for a 69 bug:

Screen Shot 2014-09-04 at 6.10.30 PM.png

I have 165R15 coker tires, and the diameter was calculated via: &

The ratios I got from the VW manual, and the screen shot is from my Numbers spreadsheet (email me and I’ll send it to you).

Here are my current speeds for a given RPM and a given gear. Max motor RPM is around 5000 (maybe 5500, but that is pushing it), so I have to shift before then. I don’t use first; it is pointless (I have enough torque to not need it), too jerky, and would have to quickly shift.

Screen Shot 2014-09-04 at 6.12.07 PM.png

I always start in 2nd, shift into 3rd at about 40mph, and 4th at 65mph; this keeps me under the 5,000 RPM limit. I have a top speed of a bit under 100mph, based on the RPM.

So, the diff ratio is 4.375 (also called 4.38); also known as the “ring and pinion” gear ratio. What if I get a freeway flyer 3.88 ring and pinion? Dropping that into my spread sheet gives

Screen Shot 2014-09-04 at 6.19.11 PM.png

So, if I did this, I would: start in 2nd, shift to 3rd at about 45 mph, and shift into 4th at about 75 mph. I rarely go 75 mph; the car starts to shake a bit at high speeds, and it just isn’t designed to do that. The lower ratio would probably make the car less torquey, so I’ll stick with the standard ratio.

(c) 2008-2017 Corbin Dunn

Corbin's Treehouse is powered by WordPress. Made on a Mac.

Subscribe to RSS feeds for entries and comments.

16 queries. 0.236 seconds.