Saturday, February 25, 2017

Wings Finished Through Poly-Brush


 We've had an amazing week in mid February, warm, dry, sunny days with light to no wind.  I've been able to get a coat of Poly-Brush on all the tapes.  The last tapes also had the pinked edges smoothed with the small iron at 225 degrees.

All the wings then received a final coat of Poly-Brush.  Today I was able to get the last coat of Poly-Brush on the bottom of the last wing.  Everything is ready to start spraying Poly-Spray (silver).  Next week is forecast to be warm also.  If it stays dry I'll get started spraying.  There is hope of getting this back in the air soon.

Sunday, February 19, 2017

Wing Tapes Done

It was a beautiful day today.  I finished pruning the fruit trees in the morning and then spent the rest of the day working on the last tapes on the wings.

 The aileron push rods on the lower wings have simple metal covers screwed to the wing.  The screw plates were made form .025" aluminum and glued to the fabric with Poly-Tak cement.  I covered them with 2" tapes.
 For the sharp curves on the wing tips I needed some 3" bias cut tapes.  Because they are cut on the bias, 45 degrees to the warp and weft, they stretch when you pull on them so that they fit tight around a curve.

I have a large cutting board with a nice bias cut line.  I used my 1 meter straight edge and Fiskars pinking cutter to make the strips of tape.  The straight edge is, conveniently, 3" wide.
 On the upper wings I started with the aft corner.  I stuck it to a straight section of the tip tube with Poly-Brush and let it dry so I could pull it tight to fit the curve.  I started where I did because it's easier to clamp it to the trailing edge while the rest of it dries after pulling it.
 While the aft corner dries I used a piece of regular 3" tape to cover the straight section of the tube.  I could have heat formed the tape to a smooth fit on the lower surface but it's quicker and easier to snip it about every 3" with the pinking shears.  I'm after a WWI look not an Oshkosh award winner.
 Once the center tape dried the forward corner was done with 3" bias tape.  I started on the tip tube again, let it dry, and the pulled it around the leading edge.   One disadvantage of bias tapes is that when you pull them to fit the curve they get narrower, oh well.
All the tapes and patches are on.  The next task is to glue on all the drain grommets.  After that some more Poly-Brush and then they'll be ready for Poly-Spray.  The aluminum powder in the Poly-Spray blocks the sun's ultra-violet ray to protect the fabric.

They really look like wings and the next several days are forecast to be perfect to keep working.

Friday, February 17, 2017

Spanwise Tapes On 2 Wings


 We had a beautiful day today so I was able to get the spanwise tapes on the lower right and upper left wings, as well as the right aileron.  The patches for the aileron cutout and aileron spar worked out very well.

 One tape near the leading edge, on the bottom of the wing, is at the edge of the leading edge aluminum.  The second tape, behind it, is covering the sewn seam in the envelope.

I still need to put on the bias cut tapes at the tips and the drain grommets.

We have 4 more days of nice weather forecast so hopefully I'll be able to finish the fabric work through silver.

Thursday, February 16, 2017

Aileron Spar Tapes

While I've been waiting for another warm day I've been ironing the pinked edges of all the tapes smooth.  The Poly-Brush is a vinyl so it smooths down nicely at 225 degrees.

I also cut out some patches.  You need a 2" tape over the corners of the aileron spar and a 2" tape over the sewn seam in the n middle of the spar.  Since the spar is only a little over 4" wide it seemed better to just cut out a big patch to cover it all in one piece.

 To make the patches for the aileron spars, and the aileron cutouts in the lower wings. I cut strips of scrap fabric a little longer than each spar and ironed it smooth at 225 degrees.

While holding the fabric over the spar I used the side of a sharp No. 2 pencil to mark the corners of the spar on the fabric.
  I trimmed the fabric 1 1/4" beyond the lines so it will nicely replace the corner tapes.

I then folded the fabric along the pencil line to help it form a corner when it is stuck down with Poly-Brush.  All 4 are made and now I'm waiting for another warm, dry day.


Saturday, February 11, 2017

Finishing Tapes On Root Ribs and Aileron Cutouts


 We had another warm dry day and I was able to get the tapes on the corners of all the root ribs as well as the tape on each root seam.
 Just like I did for the ailerons I made pieces which covered the end rib for the aileron cutout in one piece.  This gives a total of 4 layers of fabric in the aileron end gap, as little as is possible.  I made the cover piece so it goes around the corner .  The spanwise tapes for the cutout will overlap it to close the corner.

Hopefully I can start the spanwise tapes on the next warm day.