Saturday, March 01, 2008

Size Does Indeed Matter...

We hit a bit of unexpected snag this week. When Chris at Tejas was laying out the lines on the wings everything was going along very well. Abet too well... When he moved to the Fuselage he was thrown for a loop. The measurements in the schematics did not align according to the detail view drawings.

It common to have some sizing issues when taking a two dimensional drawing to a 3D airplane; however, what Chris was finding was not what he expected. He knew something wasn't right, so he went the extra mile to get to the bottom of what was going on. He literally dimensioned the entire airplane and compared it to the drawing scale. His diligence reveled that the Scheme Designer drawings were 18" longer than the actual size of 252Q!

NOTE: if you recall in my last blog posting I commented on the fact that it was clear that Chris had been carefully reviewing the design docs because the pages were warn. This attention to detail is how the error was found. Many shops would have likely followed the layout as specified and painted it. When painting you lay one color down at a time. The error probably wouldn't have been found until the entire aircraft had been painted! Chalk one more up for Tejas.

We contacted Scheme Designers and they quickly spring into action. They dropped everything they were working on to help us make things right. They asked Chris to take digital photos from a specified distance. Then they overlaid their drawings on top of it. Tejas and Scheme Designers worked via a remote web conference to completely digitize the entire fuselage including windows, panels, doors, etc. Wow!

One may think that digitizing the fuselage would be the hard part, but actually it wasn't. After they got the fuselage digitized, Scheme Designers had to modify a larger design to fit a smaller airplane. It looks about the same to the naked eye, but in actuality the lines are shorter, the curves are slightly different and the width of the lines are smaller. This process was similar to taking a design off of an A36 Bonanza and applying it to an F33 Bonanza. Suffice of to say, it was a heck of a lot of work and they did it all in less than 24 hours!

Here's a screen shot of what the process looked like:

Second Color Layout -- Medium Silver
The master design document was resubmitted to us and it was passed off to Tejas to start laying down the next color. We lost a bit of time because of our unexpected fire drill, but we are swinging back on target. Here are a couple of photos with the second color stripping ready to be painted. If we don't hit any more snags, they will be done next week.

1 comment:

Anonymous said...

Well, I've read (and thoroughly enjoyed) your entire blog... 252Q is beginning to look like the plane you want her to be! I'm looking forward to seeing everything finished. As an engineer I've really fallen in love with the Mooney's, the attention to detail is amazing. One of these days I hope to be able to own one. Thanks for documenting your work.