My Glasair III Construction Diary - Page 6
By
Roger Halstead


Well, I'm at the point where I don't know which part to do first. Currently I need to check the fuselage at the cowl flange against the blueprint to make certain it's the proper shape.  I need to build the wing fixture, I need to do the rest of the horizontal stab, and I need to fit and install the firewall.  So, it's no lack of things to do, or places to work.. 

Well... It's back to work. At least a little.

3 Hours, February 1, 2003

I sealed the wood for the wing fixture using a polyurethane finish.  This was necessary as the temperature cycles at the surface due to the IR heating in the shop can be drastic in some places. The humidity is also very low.  Even kiln dried lumber tends to change shape in there, but nothing like the standard stuff from the lumberyard.

On the left is a "true" 1 X 6.  In the center is a 6" wide strip of 3/4" plywood that was laminated with the 1 X 6 as shown in a photo farther down the page..

I also sealed the front surface of the cowl flange fixture (makes tape stick better).  I need to open up several places on the fixture and possibly shim some others to get the flange to the proper shape.  Unsupported it's a bit wide and short. With the yoke in place it's close, but needs some tweaking.

2 Hours, February 5, 2003

Basically I spent the time cleaning the shop and organizing so I will have room for the base of the wing fixture on the north side of the fuselage.  I also took the braces off the fuselage yoke and marked where I need to open it up a bit.  I also started on building a brace to hold the tail at the proper height...Based on the waterline 100 marks.

1 Hour, February 18th, 2003,

With some help I carried the base for the wing fixture out the south door and around to the big east door.  Then slide the base up along the north side of the fuselage.

2 Hours, February 21, 2003.

With Joyce's help I cut a sheet of 3/4 inch plywood into 6 inch wide strips. That was a good idea, but I didn't realize the fence wasn't clamping as tight as it should and the last strip was over 7 inches wide from a bit of "fence creep"

5 Hours, February 22, 2003

Well, it seems like a roundabout way to get the frame built for the wing fixture, but I used what I had.  I originally purchased 2 X 6s to use for the frame, but they warped so bad I had to go another route.  The base of the fixture is 1/8th inch square steel tubing for rigidity. There are 10 sets of locking casters with brakes under the frame.

Note the frame is on the floor to the left and the wooden rails are to the right. Each rail was constructed, held up with a sawhorse and the saw guide, then bolted together with 2' long spacers.

I have some true 1" X  6 milled lumber, so I took those and laminated 3/4 inch oak plywood on the inside.  I now have both rails laminated (glue and screws)

 

5 Hours, February 23, 2003

I constructed the tail stand tonight.  It consists of a "sawhorse like" stand with the top being a "T" that set between the uprights.  There is a little "tuning" left on the stand and the cross braces at the bottom need to be added to keep the kegs from spreading with weight.  The stand is heavier than it needed to be, but again, I used what was handy. As one gentleman said, "this part ain't rocket science"  The fuselage needs to be leveled again, both fore and aft as well as side to side (laterally) although it is very close now.  Once the fuselage is leveled I'll have the tail about a half inch above the stand. I'll put a layer of saran wrap on the fuselage and one on the top of the stand. Then using card board I'll cut a dam to fit the fore and aft sections of the stand. This will be filled with the expandable insulating foam which should provide a form fit to hold the fuselage evenly.

I also installed the middle upright for one side on the wing fixture. For these I can use the 31 inch fir 2 X 6s which seem to have remained straight enough.

The yoke for the cowl flange is about ready to go back on.

3 Hours, February 24, 2003

I finished adding the uprights for one side of the wing fixture and added the middle one for the second side.  I have two more uprights to cut.  I also finished the tail stand and leveled the fuselage laterally. Now it's time for the water level to set the water line 100 level.

3 Hours, February 28, 2003

I finished adding the 2 X 6 uprights to the fixture and purchased a new belt sander.  Then cleaned up a whole bunch.  I'd never build a wood plane. The stuff is far too messy to work with.

3 Hours, March 1, 2003

Stood the frame upright and set it in place on the base. Then using the belt sander I cleaned up the upper surface of the back rail and most of the front.

4 Hours, March 2, 2003

I finished sanding the front rail and welded 4 steel uprights to the base.  I took the sander outside to clean it out and empty the bag.  I positioned myself so the wind was at my back and blowing away from the building.  The instant I took the bag off the wind switched and left me standing in a cloud.  Then it neatly blew about half the sawdust back under the door and into the shop.

 

That was enough to send me out to get a shop dust collector.

I'm allergic to wood dust and smoke which makes this thing well worth the money.  It also does a very good job of cleaning the filters for the whole shop fans/filters.

Once I finish the fixture and put the wing on it, I should have an extra 8 feet of space nearly the length of the shop. I really need more room for what I'm doing now, but once I get it done I will have the room I need now...<sigh>

3 Hours, March 4, 2003

I now have all but two of the wood uprights bolted to the steel uprights and have cleaned up the floor around the frame..

2 Hours, March 6, 2003

I finished the frame this morning, now it's on to the frame work to hold the wing.
I have two sheets of 3/4 inch Oak plywood fastened together.

Currently the blueprints are laid out on top of the plywood.  The little spay bottle is filled with water which I spray over the prints as a fine mist. It helps get the wrinkles and folds out with only a little weight added to flatten the paper. 

The forms will be cut out of the print and stuck to the plywood. Then each *pair* of forms will be cut together.

3 Hours, March 7, 2003

I cut the templates out of the blueprint and gave them a good soaking in clear Krylon (TM) to add strength to the old paper.  The prints are 10 years old and becoming very brittle.

I did draw the outline of one template onto the 3/4 inch plywood.

2 Hours, March 8, 2003

All the templates are cut out and their outlines have been transferred to the 3/4 inch plywood.   Each outline has two screws holding it to the plywood underneath which allows me to cut out  and shape matching templates for each side. 

3 Hours, March 11, 2003

 

I cut out all of the wood templates, marked their designations and cord line. Then I sanded and finished shaping them on the oscillating sander.  The templates are now in position on the frame.  Next comes the brackets to hold them in place.

NOTE the 4" vacuum hose to the dust collector in the photo at right and in the one above it.

The Templates shown in position.

 

2 Hours, March 13, 2003

Using the hand held jigsaw I trimmed off the ends of the 3/4" oak plywood from which the wing jigs were cut. I then set up the table saw for cutting the blocks to hold the wing jigs in place.. Using the plywood remnants I cut 8, 2 X 6 inch blocks  

3 Hours, March 14, 2003

I cut the rest of the blocks making 8, 2 X 6 inch and 28, 2 X 8 inch blocks. Set up the drill press using a jig to align the holes and drilled two holes in each of the 36 blocks.

5 Hours, March 15, 2003

I installed the blocks that hold the wing jigs in place...all 32 of them

3 Hours, March 16, 2003

I did a rough alignment of the wing jigs and rolled the wing fixture out onto the shop apron.  Then removed the wing from the original packing. 

My neighbor, Don, came over and helped carry the bottom of the wing out and put it on the fixture.  Right now, I'm glad the thing has wheels under it.  I do think I have it a tad higher than necessary, but that should be better than too low.

I need to get the two top wing sections out, cleaned, and then stood on end over in the SW corner of the shop. Then I can demolish the shipping crate, or what's left of it.  That should give me roughly a bit over 4' by 24 more feet of space in which to work.

Dust collector:  The original bag was only 30 microns and leaked the really fine dust like crazy, so I ordered a 5 micron bag.  They sent the one for the next size bigger collector which happens to have a metal fixture in the center that is about an inch larger in diameter. Soooo... They sent it back.  The new one arrived yesterday...It turns out that the one made for the model 1100 is about an inch and a half undersize in diameter and something like 14 inches taller. 

With a bit of judicious screwdriver work while using the metal band to hold the rest in place I was able to get the bag stretched over the mounting ring.  Then I took a piece of half inch thin wall conduit 17 inches long and swaged the bag support into one end and slipped the other over the support bracket.  It works just fine.  

I should hasten to point out that this is a "dust collector" not a dust filter.  It does a very good job, but I still use full shop fans with 2 micron filters to remove the dust and smoke from the air.  Fumes still require a face mask with the proper filters.  Often I wear two cartridges, an organic vapor cartridge with a dust filter over that.

5 Hours, March 17th, 2003

I did some alignment of the wing in the jigs, moved the fixture as close to the fuselage as possible and then moved the remnants of the shipping crate outside to the shop apron.  I cleaned out the north side of the shop as well as washing and polishing that part of the floor.  Things were moved back in and I started on the block sander.  Currently I have the top sections of the wing laying on top of the bottom in the fixture.  I can see now that I should have made the ceiling 14 feet instead of 11.  The top wing sections are 12 feet long.

It seems as if I spend more time building the parts to do the building, or cleaning up after parts of the project.  At least getting the shipping crate out has given me quite a bit of extra room...Maybe I should say more room as it's not really excess.  It's also nice to be working in a cleaner area instead of having the floor covered with sawdust and fiberglass powder.

5 Hours, March 23, 2003

I fitted the firewall template to the front of the fuselage and verified the contour of the cowl flange matched the print. Then Joyce held the firewall blank in place while I marked the contour from the inside.  The next step was to cut the fire wall to shape.  Using a file I trimmed a bit here and a bit there until the firewall would just fit into the opening. Now I need to mark the exhaust tunnels and nose gear well outsides on the firewall.

3 Hours, March 24, 2003

Today was mainly a clean up day.  It was warm and windy so I opened up the big shop doors on each end of the building to let the wind blow through.  Then I cleaned the dust off everything with the high pressure air hose.  I also disassembled the G-III shipping crate. It'll take me another five hours just to remove the nails from the 2 X 4s.

(Waterline 100 position Verification) I set the firewall flush with the front of the cowl flange, and lightly marked the waterline 100 marks.  Then I carefully laid the firewall template over the firewall and taped it in place.  Next I transferred the waterline 100 marks and the vertical centerline to the plywood collar that fits around the cowl flange. 

At this point the engine mount pilot holes were drilled, right through the blueprint.

Once this was done, I removed the template, clamped a straight edge across the plywood and continued the marks on the plywood across the fire wall (waterline 100 and vertical center line).  The straight edge across the waterline 100 marks is level and the vertical line shows vertical.  Both are symmetrical with the rest of the cowl flange opening within 1/16 th of an inch.  This did end up lowering the original mark on the co-pilots side by 3/16 ths of an inch. 

The vertical stabilizer is still plumb within 1/16th of an inch. (Near as I can tell...er ... measure)

5 Hours, March 25, 2003

The firewall was fitted in place, then the outlines for the nose gear wheel well and exhaust tunnels were drawn onto the back of the firewall.  Using a Dremel tool, the fiberglass was cut along those lines.

7 Hours, March 27, 2003

The "marked" fiberglass surface was removed from the back side of the firewall for the exhaust tunnels.  "Channels" were cut our for the nose gear wheel well to fit into the back of the firewall.  Then the Rochelle foam was removed from the tunnel cut outs and the channels for the nose gear wheel well.

6 Hours, March 28, 2003

Oops! Well that asymmetrical nose gear wheel well came back to haunt me.  When I started on the firewall I found the top of the wheel well was a good half inch off center towards the pilot's side.  I had dark thoughts and deep fears of having to cut out the wheel well, and replace it with a new one.  Particularly as the lower, center engine mount alignment holes were 3/4 of an inch from the wheel well on the copilot's side and only 5/16ths on the pilot's side.

The engine mount is centered over the pilot holes. Note that it is not centered over the dark lines

Then I began to think about trying to align the top of the wheel well with a bit of force as the bottom was already correct.  The well came from the factory a bit skewed.   So, if the thing was off a half inch, I would only have to push it a quarter inch to reach center.  The top should be 16 inches from each side of the fuselage while it was actually 15 and 3/4 on the copilot's side and 16 and a 1/4 on the pilot's side.

I tried several methods of pushing, but finally ended up using a plywood board against the side of the fuselage (to spread out the force) and a two inch wide board wedged between the wheel well and the board.  It took a couple of tries, but it lined up perfectly.  Lining up the top also put the part between the engine mount alignment holes into the proper position.  As the exhaust tunnel and wheel well cutouts have not been made there is no measurable distortion in the wheel well area of the belly pan.  I am going to hold off on doing the wheel well cut out until after the firewall has been bonded in place.  The diagonal brace is to hold the fuselage shape.

7 Hours, March 29, 2003

This has been a rather enlightening session.  Wayyy back early on in the fuselage construction I was concerned about the wheel well being constructed kinda off kilter, and the exhaust tunnels which were not straight across the front. I figured I'd have to add material to the front of both tunnels, but as I was fitting the firewall I found that I had to remove material from the front of both tunnels and from the top front of the wheel well.  Not only did I have to remove material, but over a half inch (in places) from all three.  That has made the front of the tunnels almost straight and the wheel well face is also straight.

 It's been, cut and fit, cut and fit, cut and fit, but the firewall now goes into the proper position.  That Dremel tool is certainly a handy item, even if I did go through five cut off wheels. (I don't have any photos of the cutting and fitting as I didn't want to handle the camera or remote with the powdered fiberglass from the cutting all over my gloves)

The fuselage needs to be leveled again as well as the finish fitting for the firewall completed before it can permanently mounted.

Well, it's kinda gotten confusing and a bit behind.  The main computer crashed after a power outage during an ice storm the night of April 3rd. The other computers came back up but it didn't.  Which means I've not only gotten behind on the diary, but may have a few things off a bit.

14 Hours, April 5 through 7, 2003 (grouped together as I'm not sure what I did on which day)

 As in Figure 56 all the surfaces required have been cut away at the back side of the firewall.   The rough cut out has been made for the nose gear wheel well bottom opening

4 Hours, April 8, 2003

I cut the fiberglass and foam out for the engine mounts on the back side of the firewall.  It took lots of time for cleanup afterwards.

3 Hours, April 10, 2003

The cutouts have had the edges beveled and are ready for sealing. The water level is in place and the fuselage is within 1/16 in from front to back and the plywood insert is ready to be placed in the firewall.  At times there is a bit of detail missing, such as the note in fitting the engine mount to the fire wall. The manual says to use the two 3/8 inch spacers supplied, but they conveniently forgot to give the part numbers, making the task one of those, "well...this part *looks* like it should be the one", rather than use part # such and such for the lower, center, engine mount spacers.

2 Hours, April 11, 2003

I sealed the edges of the exposed foam on the firewall with a thin Q-cell mix, cut the 2" X 3" Birch plywood insert for the firewall, and "potted" it into the opening previously cut in the firewall for that purpose using more of the thin Q-cell mix.  With the exception of the two lay-ups that cover the Birch plywood insert the firewall is ready to be installed.

It looks like it's about time for another page to be added as well as catching up on the photos.

513 Hours to date


If you have comments, suggestions, or corrections email me at EAA Chapter 1093

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