CREPinc.com

As you can see here, the jet engine runs perfectly over a wide range of throttles: (full video link here)

This week we’re (a) building a new steel frame and mounting everything in it and (b) setting up a dashboard with gauges and engine control computer so we get nice graphs of temperature and pressure at […]

Picked up a new lathe on Craigslist yesterday to which I will strap stepper motors and CNC-ize. It’s small enough that I can carry it around the house when neccesary (chuck pic below, tool holder pic here)

Tested everything out today. The combustion chamber fired right up and self-sustained perfectly the first time without any tweaking. That was VERY encouraging, and more so that it worked great over a wide range of mixtures. Here it is running:

We set the the whole thing up on the frame and went to town, but unfortunately things didn’t […]

Combustion chamber is done:

My mill is getting some use, but need a bigger one!

Went to the junkyard and Home Depot today - got all the big parts we need other than sensors and whatever display/microcontroller we’re going to end up using. Below is a test of the cooling and lubrication system - originally a power steering pump and a transmission cooler. The pump makes 10psi with very little […]

Thought one: Several years ago, Mike P and I built our hovercraft out of simple materials we had around. We powered it with a leaf blower at first, then tried to install my 22″ propeller (you can see the hole cut for it in the pics) but it couldn’t hold the pressure required. The leaf […]

I’ve managed to summon some extra motivation and find time recently to do some things I’ve been meaning to do for a long time. For one, I got a new driver for the mill that will run the larger motors. I got it set up and everything works beautifully, I’m just waiting until I have parts that […]

Today I did a lot of math regarding the lift of a non-airfoil wing. From the math and review of the videos, my best bet is that we aren’t properly maintaining the right angle of attack during takeoff. The leading edges aren’t near strong enough either, but that’s something I can’t fix (if anyone knows […]

This post is divided into two parts: Things I’ve done recently, and things I’ve acquired recently.
Events
Last Sunday I was up at 6am to do communications for the MS walk in Worcester. I didn’t actually need to do anything.
This Sunday I was up at 5am to get to the MIT Swapfest. Usually Ken and I come […]

I heard back in the day of someone building a hang glider from a tarp and bamboo… While I went slightly less ghetto, this Winter break I built a hang glider with the help of several friends. The thing is quite… well… take a look at the project here.

A while ago I posted regarding the network when I moved into my apartment. This winter break we finally got around to working on things and taking it from a cluster of gross to a pretty little network of lights. Internally, we have 3 separate IP segments, bridged by our Cisco 2500 routers. Additionally, […]

I’ve been working on my CNC mill over the past month. It’s based on a small manual mill made by Proxxon. I have 3 nice unipolar stepper motors, one on each axis. The motors are controlled by 3 L297s from ST Micro (these are REALLY amazing by the way…) to 12 TIP102 transistors used as […]

If you’ve ever been to a supermarket in a city, you’ll have likely seen a lock on one of the front wheels of the carts to prevent people from stealing them. A friend and I managed to make a transmitter so that we could the carts would lock when I walked by with the transmitter […]

I’ve collected 65 flash capacitors from disposable cameras over the past months and put them together. Last night we used them to make big sparks and such… see it here.

In browsing around, I found JTrack3D on the NASA, a basic 3D satellite tracker. It works well enough, though it only lets you use predefined vectors. I’ve edited it so that you can use your own. Take a look at JackTrack3D.