#17 Rigging and Final Assembly

This post will be the last one for this project.  It was intended to cover the repair of an Easy Riser damaged in a training flight. Subsequent modifications to the Easy Riser is being covered in a seperate blog titled "Re-Thinking The Easy Riser" and can be found at
www.easyriser3.blogspot.com

RIGGING & FINAL ASSEMBLY
Ready for rigging now I've moved the right wing panels onto the frame I had bolted to the floor when I completed the pre-rigging from sheet #3.

As I put the struts in place, I recalled the problems I had noticed when learning to fly. I took great pains to patch all the tears and holes in the glider I inherited only to have the leading edge root strut bracket rivnut punch a hole right through the nice patch I had put over the previous hole. Here is a photo of that bracket “after” I drilled out the rivets, flipped it and re-installed the pop rivets.

It turns out that there is plenty of clearance now on both sides of this bracket and I get no contact with either the fabric or the gusset with the bracket in this orientation. The strut fit is not changed. If you don't do this, expect to see a nasty hole punched through the fabric by the rivnut end as shown below on Darrel's upper wing panel trailing edge which I had just patched prior to realizing what was causing it.

I found it far easier to do the tail swage first, fit the cable loop over the bracket bushing, snug up the main swage and then compress it. The plan sheet says to do the main swage first which I tried at first and right away switched to doing the tail first. Another thing I'd do different would be to thread on shrink tubing PRIOR to all swaging. When I got to the end and saw where the cable ends contact the fabric I found it necessary to tape over all the swaged cable ends. In the folded storage/transit position there was a fair amount of abrasion happening not to mention getting holes poked in my finger tips from the cable wire sticking out of the secondary swage during set-up & tear down.

In this shot I am setting the final tension on this flying wire using two vise grips held with my left hand while tightening the wire clamp with my right hand. Otherwise I'd have needed to find someone to help. This worked fine.

I made multiple trials to get the tension on all the cables just right and it took a fair amount of time to do a decent job of getting them all “just right”. My swage tool (I finally had to buy one) was a short handled Nicopress model 32 VC-VG which does both 3/32 and 1/16 swages. It required quite a bit of muscle for the 3/32 swages so I ended up cutting a pair of extension “handles” from 1 ½ inch PVC pipe. The other critical tool I was lucky enough to borrow from one of the EAA members was a Felco cable shears. This made all the cable cuts a piece of cake producing nice, clean ends.

No photos of my trials locating the control cable inside the tip of the lower wing panel. Located a hole based on how Darrel's cable was deforming the fabric and hot knifed it free-hand. Turned out fairly crappy. Should have taped a nice circle template and cut to that instead. Since this was a re-build, the bushing was already swaged onto the cable end so I had to make the hole big enough to fit the entire thing through the fabric. Rather than do an actual fabric patch (would require me to do a spot re-paint) I just used adhesive-backed sailboat Dacron patch tape which worked OK.

Next I rigged the rudder return spring exactly like I re-configured Darrel's where I removed the bungee approach specified in the UFM plans (a poor solution I felt) and installed a nutsert (that's what the guy at True Value Hardware called it).

The nutsert can be seen above laying on the wing to the right of the hole it will be installed into.

This shows the nutsert fully installed.  It is nearly flush with the tip tube surface.

I picked out a spring from the hardware store spring selection and attached it to the wing tip using two nylon washers and a small bolt.  I also picked out a steel pin, drilled it to accept a safety pin and used this as a quick connect to attach the rudder control cable during assembly.  I replaced these soon afterward with a stainless steel spring (sourced on-line through Grainger) and aluminum binding post pin (commonly available at hardware stores).

The next step was to rig the control cable which involved wrapping it around the twist grips per the plan so that the rudders come back to neutral when released.

I really liked the grip material Darrel had on his glider which was cloth handle bar tape for bicycles. I had a hard time getting anything close to long enough. The best I did was less than 10 ft so that's what I used. The underwrap was just electrical friction tape followed by the cable winding then covered by the bike tape and terminated with vinyl electrical tape on both ends.

Now I am nearly done. I got worried about the paint sticking to itself in the folded storage and transit position so I decided to wax every surface except the bottom of the lower panels using the Poly Fiber recommendation of a non-silicon based Carnuba wax which took me a good part of a day to do but I'm glad I did as you will hear about in a minute. So here's the completed glider ready to pack up and take it's second flight (recall the first one ended in disaster over 30 years ago...hence this project).

Here I am at the local test flight area the next day on the Oregon coast (Cape Kiwanda) in perfect conditions....low tide, dune to myself with a 9mph breeze right up the hill.

Although you cannot tell from this photo, the glider is sitting on a tarp I staked down in the sand so that the glider never touched the sand.  I just could not bring myself to allow that after putting all this effort into the build.

I weighed the finished glider just to have an idea how much over weight I was and it came out at 66 lbs which is about 16 lbs over. I can feel the difference just carrying the individual wing assemblies and knew I was going to have my hands full getting this thing up the dune. I was right, I made it up to about 2/3 of the way to the very top and just decided I'd be so wasted if I went any further that I'd be too exhausted to safely launch it. I was determined to not even allow it to touch the sand that when I got as far as I was going I basically took off in what felt like 10-11mph breeze. Launched fine, flew fine, rudder response was fine and the landing was easy. I could not even visualize making another climb up the dune so I packed it up and went home with a smile on my face. This makes 19 launches in an Easy Riser for me to date. I have not yet learned to reliably get my feet up onto the leading edge to assume the proper flying pilot position.  This is a critical skill in order to be in the air for any length of time and certainly at any significant altitude.  If you are interested in my experience learning to fly, please visit my other blog dedicated to the learning aspect of the Easy Riser at

easyriser2.blogspot.com

I hope this helps anyone out there in building an Easy Riser as that was my original intent.  Refinement of the rigging, designing a parachute pack mount, re-design of the internal rib layout are some of the things to be covered in a follow-on blog which you can find here:

easyriser3.blogspot.com

#16 Rudder Covering + More Masking & Painting

Since no one offered use of their paint booth last October, I was forced to wait until spring. So, here we are, April 2015 and already plenty of days warm enough to paint, however.....I ran into trouble last fall. I shot the rudders with Polybrush right over the old dope finish and then Insignia white color base coat and proceeded to mask the accent stripes. After making a masking error requiring tape removal, I found the base coat peeled off with the tape right down to the old dope finish. No point in going further. Ripped off all the covering on both rudders and set about prep'ing the frames for recovering. This pretty much shot the idea of completing the painting last fall. I found that the left rudder had actually sustained some damage once I had the covering removed so I fixed that and beefed up the aluminum ribs which are definitely the weak link in the frame structure. Here's a shot of the rudder frame leading edge rib before.

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I cut out a piece of ½ inch foam from the damaged wing rib to fit inside the aluminum rudder rib. I glued it in place using Gorilla glue which is supposed to work well on this type of foam. The stiffening effect on the rib was amazing. If I build another ER, I'd use this on all the aluminum ribs in the rudders which would also allow one to rib stitch rather than rely on the dicey fabric to aluminum bond using fabric cement (without the foam insert, the rib would just collapse as you tightened the stitch knot).

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I recalled covering these rudders back when I first built this kit that they were very difficult to do without many wrinkles so both these rudders were ugly anyway. I decided to try a different method this time around and built a quick frame out of 1X2 fir and attached a piece of fabric to it using an office stapler.

I cleaned up the aluminum frame, coated it with Polytak fabric cement and then place the wooden frame over the rudder structure.

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A small slit for the rivnut to poke through allowed the fabric to lay down nicely onto the rudder structure. I then ran a very thin line of 50/50 cement/MEK around the entire perimeter of the rudder, rubbed it in and let it dry (std process).

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I then simply cut around the perimeter leaving enough fabric to do the wrap onto the aluminum structure and got an almost wrinkle-free main area. The hard part was doing the snips and cuts to get the fabric fitted around the ends, brackets and horn. Repeated the frame process for the other side and ended up with no wrinkles after doing the final shrinking at about 300 F. Wetted out the glue on the ribs to attach fabric then applied Poly-Brush (coat #1 brushed on, coat #2 & #3 sprayed on). Same pin hole bubble issue. Just have to re-brush back over what you've just applied as you go to knock down the bubbles before the P-Brush tacks up. What you don't get will be ironed out at 225F prior to spraying.

Here are the rudders after completing all the gluing, smoothing with the iron and general detailing finishing with the first brush-on coat of Poly-Brush.

Here they are after the final sprayed on coat of Poly-Brush......

OK, on to painting. I've poly-brushed the rudders and shot the base coat of white. Two coats was sufficient. One thing I've found in getting an even coat aside from being very smooth and even on your gun passes (you need to always be aware of how far the nozzle is from the surface, what angle the spray fan is relative to your gun pass direction and how fast you move the gun along the surface). It's a tough job and was hard for me to do. I would finish a panel and then go back and look for uneveness. I would then spot spray the light areas until the whole thing looked relatively even. I tried to put on just enough color on the first coat so that the second coat was the final one. In the photo below, notice the different color masking paper on the leading edge at mid span. That stuff is the paper you use when you paint a room in your house which I suspected when I experienced bleed through. I'm not sure if it's the paper because I went to an auto paint supply shop and got their masking paper and had a little better luck but still saw it bleed through a little. I think the take away here is to DOUBLE LAYER THE MASKING PAPER OR USE A WIDE BORDER OF TAPE next to the paint line. Also helps if your technique is good enough to allow very little paint overlap onto the masking paper.  As you can see in this photo, I don't do a very good job of keeping paint off the masking paper.  I was fixing a screw up here where I forgot to take the accent stripes all the way to the root on the lower panels.  I am leaving a gap at the root on the upper panels where I will strip the paint back and glue on a fabric closure with a zipper after I'm finished.  Darrel did this on his and it works really slick.

In this next photo, I've removed a piece from the other wing panel where I had used it right in the area I was painting. You can see what happened.....bleed through! So go find your local supplier for automotive painting and get your paper from them but I'd still test it first before you commit to use it to mask an entire wing....it took me a couple hours to finish one panel and that was after I got the hang of it.

I used Reducer on a Q-tip in an attempt to mellow it out a bit with limited success. I went over the area with red but could not make it go away.

Here are some shots of the masking involved in creating a simple design scheme similar to the lines on the glider Brian Porter flew in the 1976 National meet.

The blue tape in that shot is vinyl tape used in automotive trim masking. You can form it somewhat around curves. I could not do a real tight curve successfully and ended up cutting the curves for the rudders which were much smaller radii compared to the wing panel curves.

Back in the converted RV shed with the drop-down lights for painting.

Masking the rudders.

The finished rudders ready for painting.

This next photo shows my attempt at getting an even first coat of red on the rudders. I always shoot the edges first since this is where the risk of generating drips is greatest. Making a couple light passes worked best followed with filling in the rest of the surface.

Here is a shot of the final accent stripe of gold as I am removing the masking tape around the curve. Gives you an idea of the cutting and fitting I had to do in order to obtain a nice tight curve around the bend.

One thing I did which really helped get the last little bit of paint out of my cans was to use a metal shears and cut through the lip gutter then pour out the last bit of paint and rinse with a little Reducer.

I got a couple small areas where the color pulled off the Poly-Brush surface with the masking tape. Likely some contaminate I neglected to get off prior to painting. I'll need to touch it up with a fine tip

brush later.

Here are more shots of the rudder masking for both the red and gold accent stripes. Lots of time masking and re-masking to do even simple paint schemes like I'm attempting here.

As a side note, it was 58F and raining when I shot these.  I saw no problem with the paint nor did I note any difference in spraying under these cool conditions.