I spent a lot of time this last weekend fighting the timing on my sewing machine. It was one of the first times I have had a "major" issue with the timing on this machine. VERY frustrating as some of you may know. Saturday I was only able to get two gores in before I threw in the towel. Luckily, Sunday was a different story. I came in determined to get the machine back to the reliable piece of machinery it has been. An air hose, some sewing machine oil and a few choice curse words later I had it back up and running. Time to start sewing!
I had 4 gores to sew up. My game plan was to install the gore with the turning vent second to last since I would be twisting and turning it a lot and wanted it to be close to an opening to avoid the massive bunch of fabric laying on the floor next to me.
As I mentioned before, I decided to redesign the turning vent during this reassembly process. The previous vent would have worked just fine, but it was bulky and quite frankly it didn't look all that great. It was one of the sections I just threw together to get it done. My goal with this new one was to take my time and be happy with the end result. I can definitely say I am EXTREMELY happy I redesigned the turning vent. It took me about 4.5 hours from start to finish but it looks great. Oh, and just a reminder, I based the design off of Lindstrand Balloons turning vent. I have had to rebuild a few of their vents and like the simplicity of their design. Here are the photos!
Since the new turning vent design uses a normal gore as the inner turning vents, I only had to cut fabric for the outer turning vents. I pulled out my panel #3 pattern to get the right shape. (Not pictured is the diamond pattern which I also used)
I cut two 30" sections (one left and one right). I knew 30" was going to be too large for my outer turning vent, but I needed to lay it out to get a better idea of the width I would need.
I decided on a 24" (22" finished) outer turning vent. Here are the outer turning vents with the diamond pattern sewn into place. The diamond ends "should" line up with the diamond in the balloon when it is inflated. Hopefully it wont require much adjustment
The turning vent requires horizontal webbing on the outside and inside of the vent. I covered the outer turning vent webbing in the same color fabric for aesthetic purposes only
And then there were two!
This is the inside of the balloon. The webbing will be the edge of the inner turning vent. The webbing visible here is sewn adjacent to the vertical load tape (under the seam to the left)
Once the inner turning vent webbing is in place, I installed the horizontal load tapes across the entire turning vent gore and the adjacent gores.
This is the outside of the balloon. The stitching on the left is the inner turning vent tape I installed in the last two photos. The vertical load tape is seen on the right
With a sharp knife and a steady hand you simply cut the fabric between the vertical load tape and the inner turning vent tape.
Now there is a vent (not quite a turning vent yet!)
The inner turning vent requires some additional support to hold the turning vent flags. To get a straight line, I connected my match marks and marked with a grease pencil
Sewing on some inner turning vent webbing (on the inside of the balloon)
Here are the two inner horizontal bands that are sewn to the inside of the turning vent. In the next few steps I will sew the vent flaps and outer turning vent webbing to these horizontal bands.
Cut out my 18"x18" vent flaps
Added some webbing for support
Then sewed them into place at the inside edge of the inner turning vents
One vent flap complete!
Here is the completed inner turning vent with all four vent flaps. I decided to make them pink rather than Gray because the pink fabric has a higher bias strength.
Last step was to install the outer turning vents over the inner turning vents and stitch the horizontal support tapes into place. The outer vent tapes are covered in the colored fabric it will be covering. If my measurements were right, there should be a flawless edge on the diamond when the balloon is inflated. I'm keeping my fingers crossed!
Second photo showing the completed turning vent with fabric covered tapes
While I was sewing the turning vents together, I had a brainstorming session and decided to redesign other areas of the envelope. Nothing as major as the turning vents. Just small things I could do (and should have done initially) to improve the balloon. One such thing was removing the D-Rings from the throat. There were two issues with the D-rings. 1) They were heavy and 2) They could possibly rust. So off they came! I ultimately took the idea that Kubicek currently uses (Yes, others use this too) to attach the cables to their Vertical load tapes.
Zig-Zag stitch the webbing in to a 3 layer fold
Fold over to make a loop
Stitch 18" overlap from the throat edge
Here is the finished product with the throat tape installed. Cleaner, just as strong, and no worry of rust!
For those of you who are builders yourself, don't worry, I strength tested the design with this webbing and it held up just fine.
Tomorrow I will be adding the last three horizontal load tapes and closing up the last vertical load tape. If there is time, I will reinstall all the attachments and pulleys to the inside of the envelope and tie in the parachute top again.
Expect an update around Thursday or Friday!