The posts are presented in reverse chronological order (newest first). Or you can click on one of the "Labels" to see all of the posts concerning a specific topic. Click on any photo for a larger image.
All my building experience is limited to Van's RV's so I have no experience with building tube and fabric or "plans building". I have much to learn so take everything I write with a grain of salt and reasonable skepticisim.
I do not intend to follow a "traditional" path for the construction of #88. I intend to employ low level technology and $ to reduce the construction time and difficulty where possible and practical. By low level technology I am referring to CAD, laser, waterjet, CNC. For example:
- I have purchased a complete wing spar kit from Jerry Kerr.
- A rib kit from Mr. Bartoe.
- Brunton Flying Wires and Drag wires from Harvey Swack.
- CNC profiled tube kits for the fuselage, tail feathers and landing gear from VR3.
In addition I have converted all of the wing fittings, brackets, links, lugs etc. to CAD and had them cut by water jet. I have designed a laser cut wing spar drill template/jig which positions the five spar components so that all of the holes can be drilled in a complete spar as an assembly. I plan to continue converting as many parts as I can to CAD so that I can reduce the "hand-made" components to a minimum.
Note: As of June 2015 I have over 100 CAD files which provide 600+ water jet cut parts for the Skyote.
While it takes a little time, converting the design to CAD is a great way to truly understand the drawings. plus a huge amount of information has been extracted from the rather complex drawings. This can be a great help to others in understanding and interpreting the design.
The Skyote is uniquely suited for conversion to CAD in that a "computer" was used in it's original design. I have read that Mr. Bartoe used a HP calculator to "compute" the design and dimensions of the Skyote. The plans show all of the critical dimensions to three decimal places for X,Y and Z axes.
Amazingly, when I put the design into CAD the resulting 3D models agree with Mr. Bartoe's thee decimal place dimensions about 99.9% of the time. I have found one discrepancy but less than 0.030"!
If you want to build your Skyote as cheaply as possible, or if you enjoy handcrafting the same parts over and over again then my approach to building is not for you!
If you want to build your Skyote in the minimum possible time with highly accurate parts then this approach may be the answer. I personally get a lot of satisfaction out of organizing the project so that it can be produced accurately. Hopefully some of this work will prove useful to others in the future.
Wednesday, November 16, 2011
I would really like to have the 4 into 1 exhaust on the Skyote but it is just too bulky and heavy for the little Skyote. I managed to fit it all in but it would be difficult to get the cowl off plus the primary pipes were quite close to several important parts of the air frame. Did I mention that it was heavy? So I reverted to a system which is very similar to the set-up used on the O-200 powered Legend Cub. It is simple and sounds pretty good as well.
The finished pipes will be similar to this except the exhaust pipe will be more vertical and near the center. Also, no cabin heat muff.
Saturday, November 5, 2011
I purchased an exhaust mock-up kit from Aircraft Exhaust, Inc. It includes exhaust stack stubs, a 4 into 1 collector and instructions. I got the PVC pipe and fittings from Lowe's.
The PVC tubing and fittings are somewhat larger in diameter than the stainless tubing which will make up the actual exhaust system. This gives a little extra clearance in tight fitting areas.
All of the primary tubes should be of equal length.
The left front cylinder (#4, blue tape) is the furtherest from the collector so it sets the minimum primary tube length. All of the others have to include extra bends to achieve the same length.
It is important to leave sufficient clearance around the tubes to allow for engine shake and to prevent unwanted heat transfer. Radiation heat shields may be necessary in a few places.
Although I intend to use a battery/starter-only system, with no alternator, I still want to leave space for the alternator if I ever change my mind. Here the alternator is installed to check for clearance. This added a little complication to the challenge. I think I am getting pretty close to satisfying all of the requirements. I still need to work out a short (6" to 8" long) tail pipe and plan the mounting tabs and brackets. Aircraft Exhaust will recommend where the joints will need to be added to avoid cracking.
All of this took about 2-1/2 days and lots of PVC pipe!