Workshop: Build Your Own Mini T-Square

While building the fuselage for my Chuperosa, I needed a way to square up the bulkheads. My regular T-squares were too big for this job, so I quickly built a simple mini T-square. It's easy to make, and if constructed correctly will be very accurate. Below are a few sequence photos with descriptions that will show you how to build one.



These are the tools you'll need. A larger drafting T-square and a builder's triangle. The ridge on the builder's triangle needs to be flush up against the blade of the T-square.



I used 1" by 1/8" bass wood strips from the hobby/art supply shop, and squared it up on the combination tri/drafting t-square and then used slow CA glue, and pinched it with my fingers for a few seconds until the glue dried.



After the glue dried, I cut the long side to match the other side of the beam. As you can see it is perfectly square.




Here's the mini T-square in action, as you can see, a normal drafting type square wouldn't work for this hand launch glider. If you build one, please let me know about it and post a comment.

Airplanes: Chuperosa Part Two

I have started construction on the replacement wing for my Chuperosa RC glider. Below you can see the stack of 1/16" blanks along with the aluminum root and tip templates. These will be formed into a stack, bolted together, and shaped to conform to the templates. Luckily, my Dad recommended this method, as I was unsure of how to proceed after I destroyed the foam core wing. I found an application that seems like it could work, but since the free version is cripple-ware, I could not be bothered with it. The method I chose should work just fine, and is described in detail here. (Link is a PDF) That link by the way, is an awesome reference and true wealth of knowledge for RC glider builders and pilots alike. The RC Soaring Digest is a great example of the open source
philosophy, and they allow anyone complete and unrestricted access to their archives. Let us know what your favorite spots on the web/library/newsstand are for RC model/hobbies by posting a comment.

Robotics: Infra-Tank!

Here is a 47 sec. clip of my latest bot I call Infra-Tank due to the fact that it is controlled with my infrared stereo remote controller. This is a custom design/build, but is based on the parallax boe-bot. The tank tread kit is from tamiya and the aluminum plate chassis is from K&S Engineering. It uses 2 servos modified for continuous rotation, and is guided by the BS2 microcontroller from parallax. You can build your own by using these directions as a rough guide. I would eventually like to attach a web cam or gripper- but the weather is finally starting to get nice here in MN, so I need to get my airplanes ready! Your thoughts and comments are always appreciated.

Workshop: DIY Measuring Dividers

Here's a simple tool that I wish I had made years ago. These dividers are perfect for measuring short distances within difficult to reach areas like fuselages and the interior of any built-up structure like wings, and tails. It is far more accurate than a ruler or the dreaded method of laying the piece of wood across the structure and just cutting- a bad habit I finally broke with this tool. It's comprised of two pieces of 1/4" square bass wood, and cut T-pins inserted with pliers. The two legs are connected with a machine screw and washer. Harder wood and better hardware could be used if you like- just remember to pare down the tips of the legs where the pins mount for better accessibility. Do you have any unique tools that you've already built? Please share with the rest of the world and post a comment!

Workshop: CA Glue Bottle Trick

Tired of your CA glue nozzle getting clogged? Use a scrap piece of music wire (1/32 or larger) with a bit of tape on the end for a little handle, and you can use it as a stopper. I've wasted too many bottles of expensive glue due to frozen tips. This stopper solves the problem. If you have any model adhesive tips, please post your comments.

Airplanes: Chuperosa Part 1

Here's a 1.5 meter 2Ch. sailplane currently in the assembly line. Called the Chuperosa- it's an old kit with sheeted foam core wings, built up fuse, and sheet tail feathers. Unfortuantely, I was dealt a setback the other week when I attempted to sheet the wings. I was using Dave Brown Southern's Sorghum for the adhesive and after I applied the glue and placed the top sheet on, I noticed it was a bit crooked so I attempted to re-set and destroyed the skin. It was very frustrating due to the time it took to make the skins. I do not recommend using that type of glue. Next time, (if I can bring myself to work with foam cores again) I will use the white glue technique as described here. So now, the next step is to scratch build a traditional wing using the root airfoil as my main pattern. It appears that the company who manufactured this kit is no longer around- if any of you have built or flown a chuperosa, know of any groups, resources associated with this model please post a comment. I will have several more posts on this project starting next week so, as always check back often! Below are the pics of the fuse, and tail assemblies and the front cover of the instruction manual

Airplanes: Mini Kestral

Here's a small scale RC glider that I recently completed called the Mini Kestral. It was designed by the master modeler Dave Robelen. It has a 38" high aspect-ratio wingspan, and is built completely out of lightweight contest grade balsa. I found the construction article in the now (unfortunately) defunct Radio Control Microflight magazine. Plans can be purchased here. I still need to install the electronics- which will not be easy due to the small size of this bird. Stay tuned for new posts when she's flight ready, along with posts from the field on the maiden flight!

Robotics: Link Crawler

Here's a bot that I built a while back that I named link crawler due to the wonky linkage. It was a bit low-end, but it actually stomped around like it might of had a purpose. It was controlled by a basic stamp microcontroller from parallaxinc, used 6 servos for motion, and was unfortunately sensor-less for its short lifespan due to the fact that this project was an exploration of walking style robots. There's something about seeing a fabricated object with moving appendages that never ceases to amaze me.

Projects: My Workbench

This was a pretty simple deal. Purchasing and transporting the materials was more difficult than the actual assembly. It is made from 2x4's and a fantastic 7' solid core office door that I scored from work which is covered with a 1/8th" hardboard veneer that was cut to match the door. My friend Eric made this possible with his miter saw and 4 runner, and I suppose his construction experience. I found the reference drawings and info/instructions here: http://www.freeww.com/workbenches.html
Below are the sequence photos: