Nose Gear Plates

The Nose Gear Plates, or NG-2 Bulkheads, are pretty much like the other bulkheads with a few additions. Construction began the same way: cut out the high-density .25″ thick foam core and sand it to match the template I fabricated a few weeks earlier.  Actually, in this case I built 2 cores, because both left and right parts are required, and they need to be perfect mirrors of each other.   “Why?” you may be asking.  As the name implies, the Nose Gear Plates serve as the attach points for the nose landing gear and its retraction devices.  If the parts are not alike, the gear installation will be skewed which could lead to bindin

g during retraction (or worse–during extension).

Adding solid hardpoints.

The inboard surface of each part was glassed with 2 plies of EBX-1800 cloth, cured, trimmed, and sanded to match the template.  On each part, there are 4 areas (bolt/attach points) that need to be strengthened by boring out the core and building up the area with glass plies instead.  This operation is a bit tricky because the hole saw needs to be positively controlled: cut too shallow and you don’t get all the core out.  Go too deep, and the hole saw cuts into the inboard plies that I had just layed up.  Using a drill press, and setting the cut depth using some scrap pieces of core helped a lot.  Then came the tedious job of cutting a bunch of circular pieces of glass.  Thousands of them.  Maybe tens of thousands.  Well, maybe I’m exaggerating a bit.  But I’m sure it was at least 100.  The circular pieces were then layed up into the holes, and the outboard sides of the parts were glassed.

But wait, there’s more.  On the outboard side of each part, 4 aluminum crush plates are bonded, faired around the edges with an epoxy/flox slurry, and glassed with some Bi-Direction (BID) cloth.  On the first crush plate, I made the mistake of sloppily applying the flox and allowing it to cure before adding the overlay BID ply, thinking it would just take a few minutes to sand it down to a smooth radius.   Wrong.  As I mentioned before, cured flox is some tough stuff.  I’d say it took about an hour to grind/file/sand that stuff down to a nice radius.  Needless to say, I didn’t repeat that mistake when installing the other 7 crush plates.

Original NG8 plate.

But wait, there’s still more.  On the inboard side, yet another aluminum crush plate (NG-8 for those of you taking serious notes) gets installed at the nose gear pivot point.  Unlike the other crush plates, this one is mechanically fastened rather than bonded.  The NG-8 plates that were supplied with the kit were in

New NG8 plate installed.

pretty bad shape: scratched, holes out-of-round, lousy countersinks, and generally not the type of parts I wanted on my airplane.  I faxed a drawing of the parts to my Dad, and he built me 2 new ones at his workshop which looked – and worked – great.
Once all the parts were installed, the last step was to mate up the 2 bulkheads, and open full size holes through both parts simultaneously.  The drill press strikes again.  That’s about it.

Nose gear plates complete.

Firewall

The Firewall construction was not unlike the other bulkheads I had recently completed: the core was cut to match a template then fiberglassed on each side.  The main difference here was that I used a .25″ thick birch plywood sheet as the core instead of high-density foam sheet.  This made the part substantially heavier than the other bulkheads, but since this is what the engine ultimately mounts to, weight = strength = good.

None of my tools were suited to accurately cut a highly curved piece of plywood, so I borrowed a jigsaw from a friend which worked quite nicely.  Plywood doesn’t sand as easily as foam (duh), so I cut the piece as close to the template line as possible to minimize the amount of edge sanding required.  Glassing was as before, except these were the largest pieces of fiberglass I had used yet – roughly 3’x4′. The other significant difference between this part and previous bulkheads was the inclusion of integral hardware.  (Hey, I finally got to use my cool Ingersoll-Rand pneumatic drill.)  If you look closely at the photo, you’ll notice 4 silver dollar sized circles in the “corners” which are the engine mount attach points.  They are actually .25″ thick aluminum plugs which were bonded into the plywood before the fiberglass was applied. Firewall screws Additionally, after the first side was glassed I bonded in 6 (.190″) countersunk screws (3 on each side) which serve as attach points for the rudder cable pulleys.  (Hey, I finally got to use that 100 degree countersink I bought at Boeing Surplus.)

The hardware was bonded to the plywood using a slurry of epoxy and cotton flox (which is finely ground cotton–almost like a powder–for those of you not “in the know”).  I had some doubts about the structural integrity of the screws bonded in with this mixture, and their ability to withstand a decent torque.  But once it cured, I was a believer: cured flox is some tough stuff.  The heads were flush on the other side, and glassed over, so unavailable for a screwdriver.

That was about it.  The completed part was set aside for installation sometime in the future when it will get fire-proofing materials applied and a metal face sheet.

FS-37 Bulkhead Part 2

As mentioned in an earlier post, the FS-37 Bulkhead – one of the more complicated layups – was my first casualty.  After the initial trim and final cure, I was sanding down the edges to meet the final contour.  The top of the part is straight, so I figured I’d sand that with the belt sander that my Dad gave me (surplus from his shop).  That damn tool was way too agressive for this composite part.   It sanded right through the edge in no time, and made a neat concave shape.   By the time I finally had a straight line, I had trimmed away much more material than planned.  Now what to do?  I had several hours (not to mention materials) invested in the part – I hated to throw it away and start all over again.  It may still be okay.  I could wait until installation and see how it fits, right?   Well, probably.  But I had just enough material to make another part, so I convinced myself to scrap this one and start all over again.  After all, this part takes 90% of the canard lifting loads and transfers them into the fuselage structure, so it’s not a trivial part.

It was a bit of a setback, but the second part came out even nicer than the first.

– – – – –

Hindsight note: After installing the canard (much later), the original FS-37 bulkhead with its slightly concave top surface would have been just fine.  A little filler between the canard and the top of the bulkhead would have been fine, provided the edge distance of the crush plate inserts was still adequate.

Forward Fuselage Bulkheads

Finally, armed with a fresh shipment of epoxy resin, I could actually start building parts.

This first part I built was the FS-16 Bulkhead.  (FS-16 represents Fuselage Station 16, meaning it will be installed 16 inches aft of aircraft datum.)   The process for building all the bulkheads is essentially the same, but the FS-16 bulkhead one is the most straight forward, which is why it’s a good starting point.  First, I obtained a piece of high-density, .25″ thick foam and trimed it roughly to the shape of the FS-16 template that I built a few weeks earlier.  The foam was then sanded/filed until it exactly matched the contour of the template.  Hey look! I made a bulkhead core.

Next, I carefully weighed out 3 parts of epoxy resin and 1 part of hardner, and mixed in some microballoons to form a light-weight slurry.  This slurry was then spread into the surface of the foam to fill any open cells, which in turn cuts down on the total amount of epoxy required for the layup, and ultimately leads to a lighter finished part.  For subsequent parts I used the Clearstream (Hudco) 8040 filler in lieu of the microballoon slurry.  Had I not taken that Aircraft Composites Course a few month earlier, I would not have learned that trick.  The SQ2000 Builder’s Manual doesn’t go into detail like that.  It specifies which materials to use, ply orientations, etc., and covers some techniques, but it isn’t an all encompassing guide to aircraft construction.  But I digress…

While the slurry was still wet (tacky), the appropriate type of fiberglass cloth was cut slightly larger than the core and layed in place.  A new batch of epoxy was mixed up (no microballoons this time) and spread over the dry fiberglass with a brush until nicely wetted out.  A small texture roller can be of assistance here to force the resin into all areas of the fiberglass cloth.  Then, while the epoxy is still wet, a layer of peel ply was layed over the fiberglass and wetted out.  The peel ply is a thin, nylon cloth which epoxy has a hard time sticking to.  After the epoxy has cured, the peel ply is removed (“peeled” away–hence the name), leaving behind a nice, even texture which is perfect for subsequence epoxy bonds.  Even if no further bonding is necessary, the use of peel ply is encouraged because it leaves such a nice finish.

I did the layup on a 1″ thick piece of particle board with Formica facesheets.  This is a nice, smooth, flat working surface.  During the over-night cure, I sandwiched the bulkhead between 2 of these boards, and placed some additional weight on top to make sure it would cure flat.  Warped bulkheads can only lead to trouble down the line.  Since it was the middle of summer, I didn’t need to worry about heat during the cure: the garage never got below 70 degrees.

The only tricky part about this process is the trim.  The manual recommended that I let the epoxy cure for a few hours until it’s tacky, then knife-trim the excess fiberglass to the shape of the foam core.  This didn’t strike me as a very good construction technique, and it limited me to glassing one side only.  If I glassed both sides, then allowed a full cure, I could just cut/sand/file the excess glass.  So that’s what I did.  Turns out that cutting the cured glass to the exact shape of the foam, without damaging the foam was harder than I thought.

For the next bulkhead, I followed the manual’s advice and knife-trimmed the excess.  Timing becomes an important factor here: if you wait too long after the epoxy has been applied, the composite becomes too hard to cut with a knife.  If you don’t wait long enough, it’s too sticky and gums up the blade.  And the ambient temperature will affect this window of opportunity, so if you’re heading off to your girlfriend’s house for dinner on some warm summer night after a layup, be sure to warn her that you have to leave in a couple hours to “trim your bulkhead.”  I’m sure she’ll understand.

And so it goes for the other bulkheads.  The shapes and layups become more complex, but the process is the same.  The FS-37 Bulkhead has numerous plies and 2 cores, and took quite some time to build, so it was the most challenging for a new builder such as myself.  As luck would have it, this part was also my first casualty, but you can read about that here.

Where’s My Epoxy?

Unloading the multitude of parts from “the crate,” it wasn’t immediately apparent to me that the one-million-or-so gallons of epoxy I needed to complete the aircraft were nowhere to be found.  I now realize the reason it wasn’t included was because epoxy is considered a hazardous material, and if it was in the crate, the entire 621 pound shipment would be considered hazardous. This would have been far more expensive to transport.  Therefore Glassic Composites elected to drop-ship the epoxy directly from the supplier, Hudco Industries.  Not a bad plan overall, but somehow their timing was way off; I don’t think Glassic placed the order with Hudco until the day my fuselage was crated.  After a couple of calls to Hudco with promises of “it should be there any day,” I finally managed to get a UPS tracking number out of them.  Sure enough, it was finally enroute, but this was about 2 weeks after I received the kit, mind you, so I was definitely getting anxious to lay up some parts.

Clearstream 9000 Epoxy from Hudco Industries

Well, UPS had other plans for my epoxy and drove a truck, or forklift, or perhaps an airplane over the box.  I believe their politically correct words entered on the www tracking page were “Container damaged in transport. Remainder returned to shipper.”  Damn!  Now I’d have to wait even longer to do my first lay up.  I did manage to keep busy during this waiting period by building bulkhead templates, but you can read about that in the next section.  Whatever careless act UPS inflicted upon my helpless epoxy, I hope it made a huge, sticky mess.

A few more calls to Hudco, and a couple of weeks later, I finally received my epoxy.  Not a million gallons, but 5 gallons of resin and about 7 quarts of hardener (the mix ratio is 3:1 by weight).   Plus some structural adhesive and 2-part filler compound.  Now I could actually build something.

Aligning the Fuselage Halves

The SQ2000 fuselage comes in two pieces – left and right halves – which makes perfect sense since it’s built in a mold.   The Velocity fuselage is also a two-piece affair, but I believe theirs is split horizontally, forming an upper and lower half.  Does one design have an advantage over the other?  Hard to say for sure, but it seems to me that the highest stresses will be travelling down the centerline of the fuselage (butt line 0) so that would give the edge to Velocity.   I’ll have to be very cautious doing the layup of this complex and important joint to make sure everything comes out perfect.

The fuselage halves arrived from the factory bonded together with structural adhesive.  The manual is very clear to point out two things:

  1. It is critical that the two fuselage halves be in perfect alignment.
  2. The factory doesn’t do this before they bond the halves together.

To the casual eye, the two halves looks pretty well aligned, and indeed they are.  But they weren’t perfect: off by about 0.125″ I’d say.  It’s too bad the factory didn’t take a few extra minutes to do the alignment, because it would save the builder several hours.

The first step was to break the blobs of structural adhesive (dark grey circles visible on the flange (mohawk)).  A hammer and chisel worked pretty well, although I did delaminate a few plies here and there.  Not to worry though, the flange gets cut off eventually.

Once all the bonds were broken, I had a little help to remove one half of the fuselage (it’s not heavy, but kind of big for one person to handle) and set it aside.  You can see the grey adhesive blobs pretty well in Photo 2.

Next I took my trusty angled grinder and ground off the remaining adhesive.  This was pretty tough stuff.  I also sanded away any loose plies that my chisel victimized.  This exercise was repeated for the other fuselage half, of course.

Side note: this was about the point my neighbor came down and said “What the hell is all that noise about?”

With a little help again, the halves were once again mated up, and carefully aligned.  There are several lines molded into the fuselage to assist with the fore/aft alignment, but nothing for vertical alignment… you just have to go by sight and feel.  Once I was satisfied, I drilled holes through the flange, installed fasteners, and just be safe, hot-glued the flanges together.  And no, I don’t wear suspenders with my belt.

By the way, special thanks to my Mom for taking the photos (featuring me) and helping me move around the fuselage pieces.   She was passing through Seattle that weekend on her way from California to Montana and I didn’t hesitate putting her to work (payback for all the dishes she made me wash as a kid)

Bulkhead Templates

I was anxious to get the project underway, but I hadn’t received my shipment of epoxy yet, so I couldn’t actually start building parts.  As I began looking through the builders’ manual to become familiar with the work that lay ahead of me, my razor-sharp brain noticed a common theme to each of the first few chapters; before building a bulkhead, it was necessary to first build a bulkhead template. The templates are built as follows:

  • Adhere a full sized bulkhead blue print to a piece of masonite using Scotch 77 adhesive
  • Cut the masonite to closely match the edges of the blue print
  • Sand the edged of the masonite to exactly match the blue print contour
  • Blow off the dust

The result is a light weight, rigid commodity that will later be used as a guide to cut out the foam core sections that will be the heart of the bulkheads. The templates also serve as a baseline by which the finished bulkheads will be checked.

Since this process did not require epoxy, I went ahead and built all the templates required for the fuselage. The way the builders’ manual is organized, I should have built one template at the beginning of each chapter, but I had to work out of sequence to keep busy during the pre-epoxy days. No big deal.

The fact is, I finished all the templates and still had no epoxy. Now what? Well, digging further into the manual, I decided it was time to align the fuselage… another epoxy-free task.

Receiving the Fuselage Kit

In mid June 1998, I received an email from the Glassic factory that my first subkit (fuselage and main spar) was about ready for shipment. There was just a small matter of sending them $11,815 first, which I did via wire transfer.  I would be receiving a single crate, roughly 6’x6’x13′ weighing 621 pounds by truck (Watkins Motor Freight), and they gave me a tracking number so that I could follow its progress from Tennessee to Washington via Watkins’ website.  And believe me, I did.

As the crate made its way westward, I started rounding up helpers as I knew I wouldn’t be able to unload the crate by myself, nor did I own a forklift.  With promises of beer and the excitement of catching the first glimpse of my soon-to-be airplane, I managed to get half-a-dozen helpers lined up.  I spoke with a Watkins dispatcher to set a firm delivery date of Monday, June 22, 1998 and requested that they deliver the crate after 4:00PM so that my friends wouldn’t have to leave work early.

Monday finally arrived and I darted home right after work to make sure everything was in order. About 3:30PM I got a call from the Watkins dispatcher, claiming that my crate had been mis-routed to downtown Seattle, and that it would be re-scheduled for a Wednesday delivery. “That sucks,” I thought. “My friends will be arriving in a few minutes, and now I’ll have to turn them back and hope they’re free and willing to return in two days. Damn.” As I went to my garage to sulk and await my helpers, I saw a somewhat lost looking guy wandering through my complex. As he approached, I could see the Watkins logo on his shirt. As we greeted each other and confirmed he had a very large crate for me, I concluded that the dispatcher didn’t know what the hell she was talking about. The driver was a little bit early, so I told him to go ahead and pull his truck in, but we may have to wait a little while until my friends arrived. I was his last stop, and he was very agreeable.

Moments later my friends started arriving and we opened the back of the truck to reveal “the crate.” Yes it was large. Yes it was wooden. Yes, it had “Fragile Aircraft Parts” stenciled on all sides. And yes, it was beat up pretty good. Or should I say it was beat up pretty bad?  I feared that I had just spent $11,815 for a bunch of wrecked parts.  The condition of the crate was too poor to attempt unloading it, so we decided to dismantle it inside the truck and take out the contents piece by piece. This actually worked out well, since the 2 fuselage halves were temporarily joined at the factory, and several more parts were loaded inside. Once that was unloaded and placed onto foam supports on my garage floor, the remaining parts took just a few minutes to unload. And to my relief, everything appeared to be undamaged. The Watkins driver offered to take away the remnants of the crate, I gladly accepted, and off he went.

The first parts arrive in my garage, June 22, 1998.

Preparing the Workshop

My garage before the "workshop" conversion.

Having recently moved into my townhome, the garage was fairly empty to begin with, so I didn’t have to store, sell, or otherwise throw out a bunch of stuff, which was nice. It was also sheet-rocked and insulated which saved even more time. The below photo is my before shot (click on the photo for a larger image). I’ve managed to misplace my after shots, but when they turn up I’ll be sure to upload them.

The first thing I did was to remove all the miscellaneous shelving that the previous owner had installed and patch up all the holes in the sheet rock. Then I primed and painted the walls and ceiling white, which took way longer than I imagined. Good thing I didn’t choose painting as a career. Next I installed (4) 4 foot fluorescent light fixtures on the ceiling so that I’d have plenty of light. There were two incandescent light fixtures in the ceiling already, so I didn’t have to do any electrical work other than swapping the fixtures for power outlets.

I wasn’t going to get off scott-free (what does that mean, anyway?) with all electrical work, however. I planned on purchasing an air compressor, and most of the larger ones I looked at ran on 240 volts AC, and my garage didn’t have a 240V outlet. I discovered that there was 240V wiring running over to my dryer, but since the dryer was gas, it was not energized. All I needed was to install a 20 amp circuit breaker in my panel, splice into this wiring, run it out to the garage, and install a NEMA 6-20 outlet. Once again, this took longer than expected, but the finished product looks pretty professional in my opinion.

What workshop would be complete without a good work bench? I thought about this for a long time, and went to Home Depot a bunch of times trying to figure the best work surface that didn’t cost a fortune. One day I was talking to a coworker about this, and he mentioned that his neighbor had some bowling alley lanes, cut up, in his yard. Sounded like a good future work bench to me, so he managed to cut off a 44″ by 8′ section for me. I had a friend with a truck help me move it… good thing, as it weighs a ton (not literally). Another friend helped me build a support frame out of 4x4s, then lift, mount, and fasten the surface to the frame. It all worked out great, and the total cost was only about $50.

In between all these projects, I was buying tools. Below is the minimum required tool list from the SQ2000 construction manual. I have obtained nearly all of these tools at this point, as well as a 6.5 HP Craftsman air compressor and a host of pneumatic tools. The compressor is a great asset, and I would encourage any would-be builders to make the investment. Regardless of the ability to run pneumatic tools, just having the air gun is a great asset for removing dust and such. The only drawback is noise–not that it bothers me, but since I live in a townhouse I worry about disturbing my neighbors.

It was June, 1998 now, and the workshop was basically complete. I bought another free-standing storage unit and put up some more shelves, including one over the work bench with a rod to hold one roll of fiberglass. I considered building an enclosure to hold several rolls of fiberglass, but decided it would be better to keep the idle rolls inside the house. I only use one weave at a time during layups (generally) and keeping the other rolls in the house will keep them dust- and moisture-free.

Soon the kit would arrive and I could focus my efforts on building a plane, instead of building a workshop…

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Choosing a Kit

Now that I had the place, it was time to decide which kitplane to buy. Several factors come into play here:

  • Design
  • Performance requirements
  • Material
  • Seating/payload
  • Configuration

From the beginning, I preferred composite kits. This may have something to do with my experience with the B-2 which is primarily a composite airframe. Composites are easy to work with, don’t exhibit fatigue or corrosion problems, are lightweight, and have obvious aerodynamic advantages when properly finished.

Performance-wise, I wanted an airplane that would cruise cross country easily, as I plan to fly from Seattle to the San Francisco Bay Area from time to time. It doesn’t need to be a rocket, but a cruise speed in the high 100’s would be nice. Good climb performance is also important since there are so many mountains along the West Coast. Short/unimproved field performance wasn’t high on my list of priorities, nor was range. Sometimes, on a long flight, a fuel stop is a welcome diversion.

Design was of premier importance to me. An airplane can have the best performance figures in the world and sell for $1000, but if it’s boxy and ugly I wouldn’t buy it. Personally, I think the Lancair line of kitplanes are among the best looking out there. The Glasairs are nice too, but they don’t have quite the style of the Lancairs. Just my opinion.

Seating: it’s gotta seat 4. Simple as that. This eliminates most kits.

Configuration: The 2 biggies are conventional and canard. Then you have your deltas, split wings, flying wings, biplanes and more, but I wasn’t really interested in any of those. I’ve always liked the look of the canard airplane. The Beech Starship, for example, is a thing of beauty, in my opinion.  Plus I think the canard design has some efficiency (2 lifiting surfaces) and safety advantages (more stall resisitent) over conventional design, but these points can be argued until the cows come home.

With these criteria in mind, the 4 kits I gave serious attention to were:

The Lancair was a bit too expensive and the Express, although a nice airplane with respectable numbers, just didn’t do it for me. I guess I just had my mind set on a canard. So it was down to the Velocity and the SQ2000.  One weekend when I was home (Bay Area), my Dad and I took a drive to Lincoln, CA to test fly a Velocity 173.  It was a solid, impressive aircraft that flew well and looked good. Once big plus for the Velocity was the fact that they’ve been in business for a while now, with a good safety record.  Glassic Composites couldn’t make that claim with their SQ2000, since it was a new kit and a new company. Nevertheless, I wanted to check it out, so I booked a flight to Tennessee and went up for a demo flight.

It’s obvious from the beginning of this web site that I ultimately chose to build the SQ2000.  Why?  Well, it flew as well as, or better than the Velocity.  It may not have been a fair comparison since I flew the Velocity 173, which is their big wing version with a lower wing loading, but the SQ2000 was much more sporty.  With it’s higher wing loading, plus the lack of flaps (like most low-end canard aircraft), it has a much higher landing speed as well, but I’m sure I can adjust to that without too much worry.  Although the overall cabin height of the SQ2000 is about 1″ less than the Velocity, I found I had more headroom since the seats are mounted lower. Since I’m 6’2″, headroom was a prime concern.   The SQ2000 is also a couple inches wider, which is nice.  I also didn’t really like the Velocity center stick.  As the pilot sitting in the left seat, having a center control stick forces you to use your right hand to control the aircraft.  To change radio or transponder settings, therefore, I would have to let go of the stick.

Another big plus that swayed me to choose the SQ2000 was the “advertised” lower construction time. The kit is much more complete than the Velocity since it uses molded wings and canards. The Velocity uses moldless construction which means I would be doing major fiberglass layups of the flying surfaces followed by countless hours of sanding and surface preparation. To top it all off, the SQ2000-XP kit cost the same as a Velocity 173 RG Elite kit.  I placed my order in March, 1998 for the fuselage/spar subkit (another Glassic benefit–pay for subkits as you go rather than purchasing the whole thing up front).

It would be about 4 months before I received the fuselage/spar subkit, which gave me plenty of time to convert my garage into a respectable workshop, buy tools, and do whatever else needed to be done.  I also took a weekend course on composite aircraft construction put on by Alexander SportAir Workshops. It cost about $200, but for the would-be airplane builder it’s money well spent.