Creamy Robot Goodness

Just letting everyone know that I have added a “Contact” form (look under “Pages”), so there is finally a way to get hold of me.

Wow, this is out of date! The website had some technical problems (cough) a while back and I just didn’t have time to deal with it, and a subsequent hard drive crash didn’t help the matter. I still don’t really have time, but I’m going to see if I can get the website fixed up some time soon. A lot has happened and there are a lot of posts I want to put up. Hopefully I’ll be able to soon. Busy busy!

Today was the last day of a fantastic 4-day class in Casper, Wyoming, entitled, “Design & Make Your Own Solid Rocket Motors“. Oh man, what a cool class. Best vacation ever, hands down. John Wickman, who teaches the class, is great and knows a ton. The class covers all kinds of solid propellant, but focuses the most on those using Ammonium Nitrate (AN), rather than the more typical Ammonium Perchlorate (AP). AN generally has a slightly lower Isp than AP, but it burns slower and cooler, making it more ideal for long-burn motors. Why am I interested in long-burn motors? I want to make a guided rocket. That’s the plan right now, anyway. Still working on all my permits to build the motors, and haven’t found much about the legality of developing a guided rocket. Sure, guided rockets are on the ITAR munitions list, but so are GPS receivers, and nobody’s having a fit about those! I know the FAA has some special restrictions on motors with >15 second burn times, but that doesn’t seem insurmountable at all. Anybody? (d g sharp at g mail dot com)

Here is a video of my motor being test-fired. It comes in somewhere in the J ballpark (I haven’t checked the data), is made of PVC pipe and other inexpensive materials, and was designed to have a progressive burn.

On a side note, the class is taught at Wickman’s workshop, which is located right beside the Casper airport. Today after we were done firing off our motors, Air Force 2 flew in with the vice president. The Secret Service agent standing atop the building was watching my car as I drove off. I took a drive over to Casper Mountain to check it out and see snow up close again, and sure enough, from 11 miles away, you could barely make out the airport. Here’s a small piece of the picture. The white plane with the partially blue tail is Air Force 2.

Status so far:

• The cardboard Quik-Tube has been fiberglassed and the payload bay has been cut. I should probably square the ends up better, but the cuts are made at least. It’s funny that in my whole machine shop I really don’t have a good tool for cutting or squaring an 8″ cardboard tube.
• My rocket design has been approved by one of the TAP members that I’ll need to sign my Tripoli certification papers.
• The second altimeter (a G-Wiz MC2) has been purchased and received. This will be the main flight computer, with my Perfectflite MiniAlt/WD backing it up.
• The motor (a Loki Research M1882) and propellant have been ordered. Neither has been charged to my credit card yet.

Started on the fins today. I’d hoped to get one knocked out but I realized my mill is too small to cut the fin out when you add the mounting tab. Argh. The first fin blank I made by sandwiching copper-clad G10 FR4 fiberglass (1/16″) around a layer of 2mm Cell Foam. I think the materials are good. The first blank I made used CA glue (superglue, to the layman) to hold it together. For the rest of the fins I will probably use a very thin layer of epoxy instead — the CA holds the foam on very strong, but it’s basically impossible to coat the entire surface with CA, so in my opinion the sandwich’s structural integrity is compromised.

What else? Got the keys to the new place today, and moved 3 small boxes. Heh. Moving stinks.

I’ve decided for sure that I want to go for my Level 3 High-Power Rocketry certification as my next major project, and I want to shoot for launching it at Red Glare, down at Higgs Farm in Price, MD, in April. I’ve tentatively settled on a 7.5″ diameter airframe (possibly sono tube that has been reinforced with fiberglass and vacuum-bagged) and a small Loki Research M motor. So far the simulations are looking good. This rocket will be a lot of work and a lot of money, but I am looking forward to it almost as a kind of break. See, my last rocket work was Jujubee. It was a cool project, with lots and lots of new ground I had to break. I was re-inventing everything just to make it fit within my size constraints while still meeting the strict stress requirements imposed by the cannon launcher… I’m looking forward to being able to just do something straightforward and simple, with room and thrust to spare.

On a side note, tomorrow I’ll be receiving my Bladerunner I ordered from rctoys.com. I had some project ideas relating to this (mostly focusing around trying to use back-EMF and inertial/magnetic sensors to close the loop and eliminate most of the need to trim the motors, and possibly even make it semi-autonomous). But now with the new focus on the Level 3 project, this will probably be relegated to “toy” status for a while.

What else? Well, me and Heeten are probably moving around the end of March. It’s a house with a small garage (suitable for curing epoxy, etc), a spare bedroom, and (best of all) a basement that I can move my little machine shop into.

I firmly believe that.

Netflix is great.

Truly, I am the greatest procrastinator of all time.