Sunday, April 05, 2009

Furnace and Wing Stand

After a shakedown period, I finally got my Dad's old furnace on-line. Sure nice to work in a non oxygen-depleted atmosphere at humidity levels below 100%. Here is final install pic:


I was ready to mount the fuselage on the rotisserie stand, however, I needed to do something with the wings. Therefore, I devised the following wing stand to stage wings, both now and after covering and painting. I also wanted something that I could use to transport completed wings to the airport where they will be attached eventually. It was dimensioned off of a 4x8 sheet of 3/4" plywood with height set to accomodate 50" wing. It has heavy duty castering wheels. Should hold all of the smaller covered pieces between wings. Next step is to mount wings and get the fuse on the stand for covering.

Covering: Left & Right Elevators

The last of the control surface pieces and doors are now complete, having finished the elevators. First pic shows two coats of U500 applied for installation of bottom panel.


Next pic shows bottom panel tacked on with thinned U500 and then ready for trimming of fabric and gluing of fabric around tube.


Next pic shows final glued on panel, trimmed and ironed and ready to be tautened with the iron.



Rib stitching was completed like before, along centerline of elevator.

On the bottom side of the right elevator, a lexan exit ring was installed to daylight trim control wire. A lexan drain grommet was also glued. Both are ready for patches.

Here is completed bottom of right elevator with both top and bottom panels glued on and tautened stepwise with an iron. Patches also glued on and ironed. Ready for pinked 2" tapes.

Here are both elevators following gluing of 2" tapes and final ironing.
Next phase of work will be covering the fuselage.

Sunday, March 15, 2009

Covering: Right Horizontal Stabilizer

I'm reaching the end of covering the smaller items, having just completed the right horiz stab. Next are the two ailerons and then on to the fuselage and wings. Some production time was lost on this item, due to a week-long stream restoration training in NC and installation of my Dad's old furnace in my shop. I wired a programmable thermostat to run the LP furnace, so that I can arrive to a pre-heated shop. This will provide huge incentive to initiate daily work, which is mostly occuring in evenings following kid bed-time. The new setup will also vent all of the off-gas outside. Previously, I just ran a propane space-heater which did fine heating things up quick, but it flooded the room with moisture and robbed the room of oxygen--not the greatest situation.

Saturday, February 21, 2009

Covering: Left Horiz Stabilizer

The left LH stab is complete and was most time-consuming control surface to date. First pic shows panel glued to one side.


Next pic shows above panel trimmed and ironed down. Anti-chafe tape was applied to rib edges.


Each of the ribs has drilled holes where fabric is attached with rivets rather than with rib stitches.

Here is closeup of lexan strips which are adhered on to wing with double sided tape. Holes are then burned through with a heat knife. The melted build up is then trimmed with a razor blade and then riveted to rib.


Here is completed unit before patches and tape. After gluing down second panel I noticed that glue had pulled down fabric below tangent point. Not sure how to pull fabric up, I contacted Rans and they recommended using a needle. This worked OK.


Here is final LH stab with patches and tape glued and ironed down, including over riveted area.


Sunday, February 15, 2009

Covering: Rudder

The rudder was completed yesterday. Individual pieces of fabric were attached to each side. Major challenge was rib stitching at rib locations. Stitching is required to keep surface from ballooning out when negative pressure is created by slipstream over airfoil. Finally, determined that should use a square knot. Was worried about pulling large knot size through hole, for fear of tearing fabric, but determined that permissible to use hot knife to enlarge hole for passage. Can see knot locations where diamond shaped patches were placed. Lexan reinforcement strips were placed at rear bottom of rudder and covered with patches.

Monday, January 26, 2009

Covering: Ailerons

Finally got the ailerons done. Process is identical to flaps. First pic shows fabric fastened to leading edge with clamps, in preparation for notching fabric at rib locations.

Next pic shows fabric glued to leading edge and then another coat of glue applied for bonding of other fabric end to LE.

Below are completed ailerons. Now onto elevator and horizontal stabilizer control surfaces.

Sunday, January 11, 2009

Covering: Flaps

I completed covering both flaps this weekend, which began on New Years Eve. The process will be similar to the ailerons and involves gluing fabric to leading edge, then wrapping around trailing edge and gluing to leading edge. Fabric overlap on the ends is then folded over and glued. Once fabric is secured on all sides with glue, the fabric can then be ironed and tautened. A drain grommet is installed on the inner bottom lowest point of the control surface. A grommet is just a small plastic looking washer which is glued to the fabric. A 2" patch is glued over it and later a hole will be burned through the grommet with a heat knife. Several other patches were glued to the flap where fasteners will penetrate through holes in the flap. End patches were fabricated and glued on. Then 2" tape was glued on LE and TE. First pic below shows masking tape placed on sharp part of ribs. The forward and aft part of ribs were smashed down and then smoothed with a dremel wire brush bit. Important to either tape over or smooth out any sharp points which could tear fabric. First pic shows base coat of concentrated glue on metal, then application of dilute adhesive being brushed over fabric to dissolve underlying glue and pull up through fabric matrix. Talking with Rans, I've begun applying two coats of concentrated U500 instead of one heavy coat. Surface prep cleaning of metal consists of naptha and then scotchbrite. The latter helps scratch the metal and enhance glue bonding.
Below pic shows completed flaps finished with tape. I punched holes where appropriate with an awl now as finding them later following painting will be difficult. Straight MEK works well cleaning up any glue off fabric which I'm told will be visible following paint.

I've been breathing the vapors in a closed garage so far (hard to justify opening garage door when 10 degrees outside), but after a long day yesterday I've had a persistent headache. Will begin using a supplied-air setup which I had purchased for later painting.

I've thrown away the razor blades for trimming fabric, as I had to redo a door earlier after tearing finished surface. A good pair of small sewing sizers (like used for fly-tying) works will for trimming excess fabric on glue joint. I've also learned to forego using a sharpie to mark lines on fabric, as MEK will dissolve and bleed. Soft lead pencil works great. A black and decker electric shears works great for cutting large pieces of fabric off the roll.