lwinger
Joined: 21 Jun 2006
Posts: 229
Location: Tustin, CA
|
 Posted: Tue Jan 27, 2009 7:01 am Post subject: Note to 650 plans builders re: top skin dimensions |
 |
|
I'm at the point of making and installing my top skin. 6-B-21 calls out dimensions along the center line of the top skin where it intersects with the three bulkheads. My experience showed those dimensions to be wrong. They were too close together to maintain parallell bulkheads. Yesterday i followed up with Travis at ZAC and he was very helpful. The plans show the angle of the middle bulkhead at 84 degrees, but show no angle on the baggage back and aft bulkheads. On the other hand, all three have a bottom flange set at 84 degrees, which would imply that they should stay at that angle. Travis agreed that they were intended to be parallel, but recognized that the dimensions on the plans for the top-to-top locations didn't sound right. He physically measured on the 650 made by Zenair that they keep in their shop, and it agreed with the plans. It turns out that this is because Zenair made the prototype aircraft, put their top skin on, liked the way it looked and then measured the distance off the plane, not from predetermined calculations. In reality, the baggage back bulkhead on the Zenair 650 sits at 82 degrees --- and everything still works! So the distances on the plans will produce a back-tipping baggage back bulkhead. In CAD, Travis calculated that the dimensions from aft to middle should be 646.5mm and from middle to baggage back should be 875.2mm. That should maintain 84 degrees on all bulkheads. Having said that, he indicated that all that really matters is that the top skin fits and looks nice, and that the baggage back bulkhead is somewhere near 84 degrees. Obviously the point in space created by the front edge of the top skin as it relates to the canopy (installed later) is not hyper critical.
| | - The Matronics Zenith650-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?Zenith650-List |
|
_________________
Larry Winger
Tustin, CA
Plans building 601XL/650 with Corvair
Installing fuel system
www.mykitlog.com/lwinger |
|
Get Email Distribution Too!
FAQ
Search
Memberlist
Usergroups
Register
Profile
Log in to check your private messages
Log in
