My Glasair III Construction Diary - Page 11
By
Roger Halstead

907 Hours total to start of this page

I probably should have started this page a bit sooner as page 10 was getting pretty large.  There are still a number of photos to go on page 10.

3 Hours November 28

I removed the engine mount, then Joyce held the SS nut backing plates (for the engine mount bolts) in place while I marked them from the front side of the firewall. Not enough hands to shoot any pictures.

I have the "new" style elevator hinges ready to install and the elevator sections marked for cutting.  I've marked the inside ribs for cutting and have one elevator shear web cut.  I have filled most of the voids I've found in the engine mount attach point reinforcement areas.

Note the spacer above the hinge in the center photo.  Those are two, two layer laminates at roughly 016 each for a total of 0.064", or about the thickness of the mill fiber and resin mix between the shear web and jigged panel.  This extra thickness was used when measuring the centerline on the shearweb so the hinges will be centered once the horizontal stabilizer is closed.

I've also drawn up a fixture to hold the stabilizer and elevator out in the shop along with a parts list.  I might even get that constructed tomorrow.  It should make working on the stabilizer and elevator a lot easier. (OK... So, it took a wee bit longer.)

It seems as if I spend more time building things to build the thing, that I do building the thing!

The last week plus a bit, has been spent building the fixture out in the shop to hold the horizontal stab.  This has taken a bit of experimenting.  The fixture is of welded 1" 14 gage square steel tubing 8' long, by 3' wide and 33" high.  It rides on 6 locking castors and has 6, 5/8" leveling bolts.  The top is true within a few thousands, or as close as I can measure using a straight edge.  

The experimentation comes from trying to build a table top, or work surface that is as flat and true as the steel frame.    The original fixture that held the horizontal stabilizer was only 2' wide by 8' long and was made out of 3/4" Oak plywood.  However it was taken to the basement as soon as it was brought home. It was also placed on top of two very heavy desk tops with a Formica (TM) surface.   The temperature and humidity was pretty much stable and on the order of 60 degrees and 40%.  The shop, OTOH holds a pretty constant temperature of a bit over 70F for working on the fiberglass and resin, BUT that heat comes from an IR heater.  An IR heater does a very nice job of heating the shop and it's economical, BUT the side facing the heater gets warm while the other doesn't. That and the humidity out there in the Fall and Winter is on the order of 20-22%.  The low humidity and heating one side considerably warmer than the other tends to cause wood to want to curl a bit.  Well, actually it's quite a bit. Add to that the lumber we purchase now days isn't well cured and it curls a *lot*. 

Had I given the plywood a couple of coats of Polyurethane on both sides before taking it to the shop might have kept it stable, but two days after I bolted it to the frame it had scalloped edges and was off by a good 1/8" in places.

So, I went to plan B which I had thought about at the beginning, but I thought the plywood would look nicer.. I purchased a hollow core door, took it to the basement and gave each side a good coating of Polyurethane. It's a tad short but I can add a foot of plywood shimmed to give a flat surface at each end.

I haven't kept track of the hours required to build the fixture, but drawing up and welding the frame probably ran about 6 hours. (I'm not counting all the messing with the plywood and then going to the door... time.

The door now has 3 coats of Polyurethane on each side.

2 Hours December 13

Progress is slow:  With the hollow core door being 7' and the horizontal stabilizer being about 8 1/2 feet, I picked up two 3' 1" long by 14 inches wide,  pieces of Yellow Popular milled to 1 5/16" thick.  The ends and one side are still rough.  I'll trim them to match the hollow core door, glue the whole works together and then "hot glue" the assembly to the steel frame.  The end sections were given a coat of Polyurethane one each side which was sanded smooth after the coat dried.  Each side was then given one more coat.

I ordered some spare hardware (bolts, nuts, washers, etc) and I'm reorganizing the area around the wing fixture so I can also work on it.

December 14

I cut some 2" X 8" X 1" Yellow Popular to use as positioning blocks. These were to keep the hollow core door from moving around in the frame.  I had wondered how I was going to fasten the door to the frame, but that problem was resolved when a bit of excess "Gorilla Glue" (TM) that was used to fasten the positioning blocks got onto the door and frame. They are now as one!  The Yellow Popular end pieces were each given another coat of Polyurethane on each side. They now look like glass.  Each of those end pieces weighs more than the door.

December 15

When gluing the rest of the positioning blocks I used a bit of extra glue and pushed the blocks up against the frame.  The blocks were clamped in place while the glue cured.  I then moistened the ends of the hollow core door, gave those ends a coat of Gorilla Glue (TM) and pressed the large Yellow Popular extensions in place.  I also used 1 X 2 X 8 blocks glued across the bottom of the joint and clamped them in place.  The ends are now part of the door... and frame.

2 Hours December 16

Using the grinder I did some more fitting of the engine mount nut backing plates on the bottom left and right sides. The forward face of each was sanded to get a good bonding surface.

The last of the parts for the horizontal stabilizer fixture were brought from the basement to the shop.

6 Hours December 17

The extra hardware arrived.

I permanently mounted the engine mount bolt, nut backing plates on the bottom left and right using a mill fiber mix,  The mounting face of the backing plates was cleaned with Acetone.  The engine mount bolts were thoroughly waxed with mold release and the mill fiber mix put in place. The backing plate was then slid over the bolt followed by the washer and nut. The nut was "finger tightened" as far as it would go without causing the backing plate to tilt.  

While working on the fuselage I also marked the position for the header tank filler neck. I also measured and marked the tank outline inside on the firewall.  I now have the drawing (on paper) for the sides, bottom, and back of the header tank.

I gave the two 48 1/2 inch wedges that fit under the shear web of horizontal stab, a coat of Polyurethane and let dry. I have cleaned all the hot glue off the other alignment guides and am ready to mount the horizontal stab on the work table.

4 Hours December 18

I drilled and shaped the SS nut backing plate for the top on the copilot's side.  Drilled out the bolt hole to 7/16"sanded the fiberglass surface, waxed the bolt, inserted the bolt, filled the area with a stiff, mill fiber mix, installed the backing plate, washer, and nut.  Then trimmed the fill.

Leveled and hot glued the 48 1/2 inch wedges to the new work table and positioned the horizontal stabilizer.  I hot glued positioning blocks along the ends and front of the stabilizer, then inserted leveling wedges and hot glued them in place.

I'm back to being ready to install the elevator hinges.

6 Hours December 19

I installed the SS nut backing plate on the top pilot's side as described above.  I also drilled the holes and temporarily installed the new style Elevator hinges on the horizontal stabilizer shear web. The nut plates are ready to install, but most of the bolts ( AN4-10A) are too long and will run out of threads before the bolt is tight  I could probably use AN4-7 and AN4-8 in this case (they are only about 12 cents  USD each). This is with "3" thick aluminum washers (AN960PD-416) under the bolt head.

2 Hours December 20

Using the sanding drum and a cut-off disk I trimmed the excess cured mill fiber to a flat bevel from the end of each SS nut backing plate to the firewall.

2 Hours December 21

I spent some time fitting the nut plates for the elevator hinge bolts, but I need "modeling clay" to fill the threads and I need to order some various length bolts.  Being that the bolts won't be here until after Christmas if I order them tonight, I'm going to go through the manual (at least a ways) and select some more hardware.  As long as I'm ordering I might as well make it worth the shipping. 

I started reorganizing the shop to make more room and get the wing ready to work on.  Of course there are still the center bolts on the engine mount and the header tank so I don't have to worry about something to do while waiting for the bolts...and modeling clay.

I think it's going to take about two days of work to get things moved around in the shop and the place cleaned up.  I need a place to stand the upper wing panels on end until I get the rear spar and ribs installed. Then the upper panels can set in place except when I'm working in that particular area.

5 Hours December 22

Using a long 3/8" bit, I drilled holes for the center engine mount attach bolts.  I drilled out the SS nut backing plates and fitted them to the inside.  I also did some more fitting on the elevator hinges and now have some modeling clay to fill the threads so the nuts can be permanently mounted. 

The elevator shells are ready to be cut in half, the end ribs are ready and I'm ready to fit the elevator shear webs.

2 Hours December 23

With Joyce's help I removed the engine mount and sanded the copilots side fiberglass lay-ups under the lower, center attach point.  It took 4 tries to get it right, but I didn't want to remove too much and then have to do another lay-up.  We reattached the mount and I'm prepping the inside surface to do the two lower center SS nut backing plates.

On the horizontal stab: I am now fitting the K2000-4 nut plates.  I have also cut the elevator panels into halves.

December 24? (I have to start my Christmas shopping some time)

3 Hours December 25

I finished the two lower, center, engine mount, attach point, reinforcement, nut backing plate installation.  Finished being a relative term at this point in the construction.  I still have some trimming and even a bit of fill here and there to make it look pretty.

3 Hours December 26

I did a little  trimming  around the lower, center, reinforcements. For the horizontal stab I fitted all the K2000-4 nut plates, and drilled holes through the back side of the shear web matching the holes in the nut plate tabs.  I have pop riveted all the nut plates in place except two.

This is an interesting exercise as the pop rivet gun won't fit into the shear web and ribs far enough to work on the ends. The end of the tool also hits the raised (threaded) portion of the nut plate preventing the inside rivet from being accessed.  I solved this by simply slipping a number of washers over the shank of the rivet. (will be in photos).  I didn't think it would take near 3 hours to drill 24 holes and insert 1/16" pop rivets.

3 Hours December 27

Bill Albe stopped by and helped me rotate the fuselage upside down on the supports. This is to allow me to pot the header tank filler neck more easily.

I made a small tool using an Aluminum rod 1/4 inch in diameter and 3/8" long. I drilled this to accept the shank on the 1/16"pop rivets.  I beveled the one end about 20 degrees. This, unlike the washers allows me to go in at an angle and still have the pop rivet head flat.  It worked very well to finish up the pop rivets on the horizontal stab.

Ouch!   I decided to hot glue a block over the outside of the opening for the header tank filler neck.  I put a dab of hot glue on each end of the block and carefully put the gun off to one side.  I then slide under the nose of  the fuselage and laid back on a small throw rug. As I reached up to put the block in place my head leaned back. I felt something really hot.  I knew I'd been had and there was nothing I could do about it.  I don't know how that dab of hot glue got on the carpet and I could find no sign of it later.    I didn't count the half hour it took to get the stuff out of what little hair I have left.  Sometimes  there is an advantage to being almost bald.

2 Hours December 28

I knocked the wood block off the fuselage (see previous entry), cleaned the now cold, hot glue off the fuselage and taped a 1" wide steel ruler (from a combination square) over the opening for the filler neck.  I checked the filler neck fit and then made a relatively thick mill fiber mix and did a fillet around the filler neck.  I'll make a larger batch tomorrow and put on another layer.

Working with the alignment fixture and elevator hinges I discovered one hinge needs just a few thousandths spacer under it to make the alignment better.  The hinge is quite smooth as is, but the few thousandths makes it movement effortless and like silk.

I ordered another batch of bolts, screws, nuts, and cotter pins to give me a set of spares of variable sizes and lengths.  If they get here by Friday I may actually be able to close the stab yet this year, although I'm not really optimistic. 

I'm hoping for at least one good day to either end the year or start the new one with a bunch of flying in the Debonair.  It's time to take a break from building.  It's also time to get the photos up-to-date.

3 Hours December 30

I finished the second fillet around the filler neck for the header tank and the fuselage is now ready to be turned back upright.   I have also aligned the hinges on the horizontal stabilizer. The extra hardware arrived today and I plan on finishing up the inside of the stab tomorrow... with luck.  OK, so I was a bit optimistic.

4 Hours, December 31

Bob and Denny stopped by to help me rotate the fuselage back to the upright position.  I put the work table for the horizontal stab back into position and re-leveled.  I hot glued four, 1 X 2 X 5 blocks left over from building the work table to the top to hold the horizontal stabilizer on edge with the hinges down.

3 Hours January 1, 2005

I mixed up a 15 gram, mill fiber, Cabosil, resin batch which gave me enough to pot 5 of the K2000-4 nut plates in the shear web.  I also did some trimming around the engine mount attach point reinforcements and ground out some fill along the edge of the wing opening on the copilot's side so I could get the rubber tubing to fit better over the edge.  (The rubber tubing is a safety device to protect me crawling in and out)

4 Hours January 2

I mixed up a large enough mill fiber batch to pot the rest of the K2000-4 nut plates. I let them cure and was fitting the small cloth pieces that go over the mill fiber (with a cut out for the modeling clay) when I discovered a little piece of Scotch Tape (TM) sticking up at the one end of the shear web.  It was between the mill fiber mix and the edge of the shear web.  It was a piece used to hole the 2 layer laminates as spacers when I measured the centerline of the shear web.  Unfortunately I couldn't tell how far down it went, so it was out with the Dremel tool and a burr.  I must be getting enough practice as I was able to carve right down to the face of the shear web and the nut place without cutting into the shear web.  The piece of tap went almost all the way to the nut plate.    So, I'm now ready to do the first layer over the fill fiber except for the one nut plate on the end where I have to put some mill fiber mix back in.

4 Hours January 3

I filled the cut out from the previous entry, let partially cure and then did one layer of the BID cloth over each nut plate.

5 Hours January 4

I trimmed the edges of the previous lay-ups and then cut the final BID cloth pieces to cover the nut plate installation and fitted them in place.  Then finished the lay-ups with about 25 grams of resin.  I prepped the ribs and jigged shell and glassed in the D-ribs using about 40 grams of resin and mill fiber.

2 Hours January 5

I fitted the NAV antenna into the leading edge of the horizontal stabilizer and covered the antenna, feed point and about 4 inches of the coax with one layer of fiberglass and resin. I also drilled the vent holes through the D-ribs and re-drilled them in the rest of the ribs.

3 Hours January 6

I drilled a 3/8" hole for the coax through the jigged shell. I then put a 4" long piece of flooded heat shrink tubing over the section of the coax that will go through the hole for protection and strength. 

I prep sanded the inside surface of the un-jigged shell, the top surfaces of the ribs, and removed the hinges and hinge bolts. With the exception  of sealing in the coax in the hole with Silastic RTV (TM) The stabilizer is ready to be closed.

2 Hours January 8

I sealed the coax into the hole in the jigged shell using Silastic RTV (TM)

Jim Dobben (EAA Tech Counselor) checked out the work and I hope to close the stabilizer Sunday afternoon.

3 Hours January 17

Well, it took a bit longer to get around to closing the stabilizer.  I gave the mating surfaces a good cleaning and  Jim Dobben came over this evening to give me a hand.  I mixed up a 100 gram and a 120 gram batch of mill fiber with a touch of Cabosil.  Then Jim and I applied the mix as directed in the manual. I looked like we were going to be a tad short so I mixed up another 40 grams.  Once I finished trimming I had about 5 grams left.

I had taken the room temperature down to 60 degrees yesterday so everything, including the resin was cool. That gave us a much longer working life for the resin so we didn't have to hurry as in the Summer when it's above 70F.

The stabilizer is in the fixture with about 80-90# of weight on top.  The rear edge is clamped to a straight edge, but it looks straight without the fixture.  I turned the temperature back up to 70 and by tomorrow I should be able to remove the stabilizer from the fixture.

3 Hours January 18

I removed the horizontal stabilizer from the fixture and cleaned it up.

I then created some uprights out of 2 X 4s I put a layer of wax paper on the horizontal stab, propped it in place and filled the area between the uprights and the stabilizer with expandable building foam.  After it had cured I removed the wax paper and trimmed the foam flush with the 2 X 4s.

At this point I had planned on getting a lot done on the G-III as Joyce was going to be gone on a bike tour for a month, but things seldom go as planned and this was no exception.  I think I spent more time fixing things around the house while she was gone instead of doing any thing constructive.  She hadn't even reached her destination before the furnace failed.  This is a time of sub zero nights in Michigan so I wasn't really thrilled when they told me the technician could be out "tomorrow" to see what was wrong, what it would cost to fix, and when they could fix it. I told them I'd call back.  With nothing to lose, I took the burner exhaust fan out. I already knew what was wrong and didn't need to pay $80 just to have someone tell me that.  The impeller had fallen off the motor shaft.  They us a thin steel spring clip to hold a plastic impeller on the shaft in the burner exhaust.  I'm surprised it lasted 5 years.  (poor design).  I replaced the clip with a piece of heavy duty, "flooded" heat shrink tubing and had it back in place with the furnace running in less than 20 minutes.  You have to replace the entire fan for $300 plus shipping and labor due to a 50 cent clip in the wrong environment.

Things did not improve after that, but the furnace is still running on the temporary repair.  I'll skip the details of major upgrades of the hardware on three of the computers except to say...One went well. 

5 Hours March 14

I sanded the rear side of the shear web and inside areas of the horizontal stabilizer shells rearward of the shear web.  I then vacuumed the area out and wiped it down with Acetone.  The next step was to fill the bolt holes with modeling clay to prevent resin from getting into the threaded portion of the K2000-4 nut plates.

I then fitted the first 4" wide by 100" long cloth strip into the space between the shells rearward of the shear web.  Starting in the center I applied the resin in 30 to 40 gram batches working out to the ends.  I left it to cure over night.

3 Hours March 15

I trimmed the edge of the previous lay-up flush with the horizontal stabilizer trailing edges, then fitted the next 4" wide X 100" long cloth strip on top of the previous lay-up.  I then lowered the temperature in the shop to 68 degrees and let stabilize.

After the temperature stabilized I applied the resin to the second lay-up in 30 to 40 gram batches.  After the lay-up was finished I put the stabilizer back in the fixture and brought the shop temperature back up to about 74 degrees F.

7 Hours March 16

I trimmed the edges of the previous lay-ups, then set the stabilizer on the work table with the leading edge facing to the rear.  I sanded and sanded... and sanded... all the gel coat and plain resin down go get a good bonding surface on the leading edge.  I then set the stabilizer on its tail with the leading edge up and wiped it down with acetone.  Using masking tape along with wax paper I masked the surfaces of the stabilizer to prevent resin drips and runs from sticking to the surface.

I applied a single lay-up to the left side and then put the stabilizer back in the fixture.  2 X 4s were used as straight edges as well as platforms to hole about 100# of weight to keep the leading edge in position while the lay-up cured.  Of course the weight pushed the leading edge together and left a giant void in the lay-up.  A bit of fresh resin and stippling pushed the cloth back into place.

2 Hours March 17

I repeated the above on the right side of the stabilizer.

3 Hours March 18

I removed the stabilizer from the fixture and trimmed any frayed edges and drips and then did the 70" lay-up over the center.  I decided to try some peel ply to see  if it would give a better edge. 

I removed the peel ply while the lay-up was still in the green state and trimmed the edges. Next were the two end lay-ups. I did not use peel ply on them.

The two piece third and fourth layers are now in.  There will be some trimming tomorrow and then the last two layers for a total of 5 lay-ups.

There are two bottles of MEKP that have been around for a while so I ran gel tests on 20 gram batches of resin.  Both gelled in a bit less than 30 minutes at 72 degrees F.  This is about the same time I am getting for the current catalyst.

4 Hours March 19

I removed the stabilizer from the fixture and turned it around to face the front of the work table. I removed the masking tape and waxed paper, then using a coarse file, the edges were trimmed of excess resin and frayed edges.  The masking tape and waxed paper were then replaced and the stabilizer set up with the front edge up to facilitate the next lay-up.

The last two layers were added.  Now to let it cure.

3 Hours March 20

Filed, shaped, sanded, cleaned, and gave the horizontal stabilizer leading edge an Acetone wipe down.  Next step will be to fill any voids, then coat the leading edge with a mill fiber/Cabosil/Q-Cell mix for shaping.

4 Hours March 21

Sand and fill, sand and fill, sand and fill... I mixed up a batch of mill fiber and Cabosil with a bunch of Q-cells thrown in for good measure (and color)  This was liberally applied to the leading edge, making sure to fill any voids. The leading edges were then covered with peel ply to help round the shape.  With the temperature at 75 in the shop I was able to remove the peel ply in about 3 hours

I chose to do most of the work shaping and filling the leading edge of the stabilizer now while it's easier to get at.  Trimmed the elevator shear webs and end ribs to fit. This is getting a bit ahead of the manual and it's time to back up a bit.

1023 Hours total to date

And with photos it's about time for another new page in the journal.

If you have comments, suggestions, or corrections email me at Support
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