Kinda funny… I’ve been waiting for warmer weather to get more done on the plane, then when warmer weather does come along I find myself with other non-airplane build chores that need to get done as well (sigh!).

Later in the afternoon I brought the epoxy wiped bottom cowling outside in prep to knock out the initial sanding with the 80 grit orbital and pad sanders.

I also included the top cowl oil check door in this afternoon’s reindeer games.  Here’s both after I finished the initial sanding of the epoxy wipes.

After bringing the bottom cowl back into the shop, I spent another good hour on it block sanding it out.  Not surprisingly I had a few minor divots that needed filled —the majority on the unmicro’d carbon fiber areas— so I added micro/West 410 to those problem areas.

Many hours later, I sanded all the added micro dabs down, then block sanded the entire bottom cowling with 150 grit wet sandpaper.

I also wet sanded the top cowl with 150 grit as well.  This makes both the top and bottom cowls ready for primer.

I then turned back onto the canopy latch system, tapping the remaining side of the modified C2 canopy latch bracket with 1/4-20 threads.

Tomorrow I’ll continue prepping components for primer & paint, as well as work to get the canopy latch system dialed in and finished.

I started off today by taking the freshly epoxy wiped (Phase II) top cowling outside to knock down the epoxy wiped surfaces in prep for priming and painting.

I grabbed this new shot (pic 1) to show that the vast majority of the pin holes were filled, the ones that can been seen after I sanded the Phase 1 epoxy wipes (pic 2).  Grant it, I haven’t sanded this round of epoxy wipes yet, but I can see that nearly all the pin holes are now filled.

I then spent about an hour sanding the top cowling with both my orbital and pad sanders, both with 80 grit sand paper.

Although I didn’t grab a shot afterwards, but next I wet sanded the top cowling with 150 grit sandpaper.

I then got busy on the bottom cowling.  I did some fine tune sanding here and there before cleaning it in prep for 4 rounds of epoxy wipes…. which I knocked out over the course of the day.

I also sanded the top cowl’s oil check door and epoxy wiped it with 4 coats as well.

Tomorrow I’ll sand down the newly epoxy-wiped parts and also plan on working on the canopy latch system.

Pressing forward!

I started out this round of airplane building by sanding down the bottom cowling’s added micro dabs, all over the micro’d areas (no pic)… I then applied one more dab to a divot afterwards.

I also sanded down and then micro’d up the top cowl oil check hatch door.

I don’t know how visible the pin holes are on the surface of the carbon fiber top cowling, but after some fairly aggressive sanding of the epoxy wiped surface, I figured I needed another 2-3 rounds of epoxy wipes.  Either that, or just micro up the entire top cowling… which I didn’t have the desire to do.

On the first round of these Phase II epoxy wipes for the top cowling, I added a bit of West 410 filler to the epoxy—mainly to add color to see how effectively I was getting the epoxy down into the pin holes (pic 1).  It looked like it was working, so after that I switched to straight West epoxy again for the next 2 (and final) epoxy wipes (pic 2).  I then left the once again epoxy wiped top cowl to cure overnight.

In between the rounds of epoxy wipes on the top cowling, I chucked up a 3/8″ end mill and “manually” (using the control pendant) milled out the bottom of the slot floor on the canopy latch handle.  I was able to get it down even with the handle (bottom of pic) and also eliminate the multiple drill-tip divots from my clearance holes.

I have to say that I’m very happy with how this task turned out.

And here’s the machined canopy latch handle.  I did another task on the mill by drilling the mounting holes, then tapping those threads to accept 8-32 screws.

I then attached the handle to the canopy latch handle frame and mounted it in the bird. Not surprisingly, it did require a bit of judicious sanding in a few spots for it to fit comfortably, but after 10 minutes of fine-tuning it fit a treat!  Here it is in the closed position.

And here we have it in the open position.  Again, I’m very pleased with how this handle turned out so far.

Since the canopy latch handle has been a work in progress for about 7 years now, I decided to make a video showing the machining of it out of actual aluminum!  Enjoy:

I’ll continue pressing forward on both top and bottom cowlings, as well as the canopy latch system in my push to get this bird done!

Although today was a bit warmer (high 30’s/low 40’s) as compared to yesterday, it was still pretty darn cold.

I started out by spending a good 1.5 hours using my orbital and pad sander with 80 grit paper to sand down the epoxy wiped top cowling.  Yeah, the epoxy had turned bad and was hard as a rock… I waited a day too long to tackle this beast and paid the price!

Here’s a plastic container I left outside the shop, the top of what is now a temporary rainwater bin had over an inch thick slab of ice on it… note the fuzzy background shot of the rinsed off top cowling “baking” in the sun to dry out.

Since I still had daylight left, I grabbed the bottom cowling and spent about the same amount of time on it as I did the top cowling… this was all hand-sanding though with 36 grit sandpaper, using various blocks and tubes to knock down the initially sanded micro.  Although there are some minor divots and low spots, again, I’m very happy with how the bottom cowling is turning out (since I had to reconstruct the aft half of it).

I then got to work doing a couple more rounds of machining on the canopy latch handle down the center slot to clean it up.  I will note that sometimes getting the CAM post processing to do exactly what you want is a pain, so I will be doing one more milling operation by hand to deepen the slot a bit (for clearance) just adjacent to where the internal pivoting rod will be located.

Other than that one-off job, the major machining is complete on the canopy latch handle.  Once I fit it into place in the fuselage side wall and confirm its position, I’ll then drill and tap the top and bottom mounting holes.

With the canopy latch handle machined, I then turned back to the bottom cowling and filled all the current minor divots and low spots with a micro/West 410 filler mix.

I also hit one minor divot on the left Turtledeck shoulder as well, which is the last of the added fills pre-epoxy wipes for that whole area as well.

Tomorrow I’ll sand down the added micro spots and work to get the bottom cowl prepped for epoxy wipes.  I’ll also fine tune the top cowling to get it finalized in its prep for primer and paint.

Although the outside temp was below freezing (~30° F), I wanted to get the micro on the bottom cowling rough sanded before it cured hard as a rock.

I spent over 45 minutes sanding it, but took breaks about every 10 minutes to go into the shop to thaw out my freezing cold hands!  I’m really pleased with how the bottom cowl shape and contour is turning out.  I plan on sanding it more thoroughly by hand either tomorrow or the next day.

I then got back to work on the canopy latch handle.  I decided to do some hole drilling down the center of the deep slot to clear out some material to help out my end mills as they gut out the center of the handle.  I used 4 different sized drill bits as I settled in and just drilled for about an hour… the final biggest bit holes are shown in the next pic.

Here we have the canopy latch handle with a good bit of the center slot material drilled out on the drill press.  Again, this should make the job of removing all the slot material much less stressful (read: less heat and more accurate) on my end mills.

Just as drilling out the slot material, this machining job took a good little bit (about 1-1/2 hour) to nug out, since I used multiple step down passes to mill the slot.

Now, this is just the initial slot material clearance machining, whereas tomorrow we’ll get more dialed in on our specs and make this thing look much nicer.

Still, looking good so far (IMO) and I’m very pleased with how this is turning out.

Pressing onward!

Below is Version 2 of the Canopy Strut Block hot of the pres… er, uh, 3D printer!  I went with basic tactical efficiency by simply using a Sharpie to color the lettering black.  I also did a rudimentary strength test by “jamming” the canopy shut with a good bit of force and this version held up fine.

Honestly, if it works once on a strong gust of wind but is sacrificed in the process, where I’d have to keep the canopy closed for a period… I can always rework the design and print another one in about an hour.  For less than an ounce, I think this is decent insurance against the canopy slamming shut due to strong winds or gusts.

Back on the turtledeck… yep, a few more divots and low spots on each side that needed some judicious minor micro filling —more so than what will/can get filled with epoxy wipes alone.

I’ll sand the added micro tomorrow and should be done with micro on the turtledeck proper and the shoulders… I’ll wait to epoxy wipe until I get the longerons micro’d up as well (and hopefully warmer weather!).

With the micro tasks completed on the turtledeck, I then did a final clean on the top cowling and did the first round of epoxy wipes (see below).  With the first epoxy wipe complete, I then got busy machining the canopy latch handle.

The stock I have on hand for the canopy latch handle is a little longer than I need, but the other dimensions (1.5″ x 3/4″) are exact to what is called for.  Here is the original aluminum stock (I think 6061?  It’s been a long while since I bought it), after I marked it using my original 3D printed handle mockup as the template.

Since I didn’t want to waste aluminum stock, and a lot of time machining both ends, I used both the horizontal and vertical band saws to notch a big chunk out of each end, the shorter end shown here.

I then did 2 separate rounds of machining: one for each end of the handle, with a break in between the two sessions for another round of epoxy wipes on the top cowling.

As you can see, here we have the external milling of the canopy latch handle completed, with the internal slot yet to do (planning to finish tomorrow).

Once all the milling was complete for the night, I did one more round of epoxy wiping on the top cowling… for 3 total coats of West epoxy.

I had actually planned on doing 4 coats total, mainly for the micro’d areas of the top cowling, and used the 205 fast hardener so it would cure faster in between each round. But as I MAY have mentioned, it’s still quite cold out and I’m struggling to keep the shop above 65° F (Marco is just a few hours north of me, and he’s already got about 7″ of snow… and folks 15 miles inland from me are getting snow as well).  In short, it was getting quite late, plus Jess had dinner made and waiting, so I made the call that 3 epoxy wipe coats was all she gets!

Tomorrow I plan on finishing the canopy latch handle machining, as well as getting the bottom cowling sanded and at least final prepped for epoxy wipes.

The turtle-DECK that is!

Yes, I busted nearly every goal I had this week, but I continue to plug along.  And dare I say, the weather is back to quite chilly once again, and is scheduled to be so this entire upcoming week.  Thus, I’m trying to knock out what chunks I can so when it does turn warmer for a good spell, I’ll be poised to strike and get the bigger stuff (underside wing ends and nose/canopy surround areas) knocked out.

For now, with a decently warm day in the high 50’s and the magic of heat lamps to keep things warm overnight, I was able to get the majority of the bottom cowling slathered up in micro.  Once I remove the bottom cowl I’ll add more to the immediate areas around the now taped up CAMLOC holes, but clearly I wanted to get the micro on the bottom cowling with it being mounted in situ to preserve the exact mounted shape as best possible.

Now, sitting on the shop floor applying micro on pretty much completely negative angled surfaces took quite a bit longer than I anticipated (over 3 hours) and took a much bigger bite out of my shop time than I had planned for.

I was able to get a plastic sheet taped in place to allow for sanding the micro’d turtledeck, but it was getting later in the evening so I decided to kick that can until tomorrow.

Which I did… and here is the initial sanding of the turtledeck on the left side. Hindsight being 20/20, if I had thought out and planned better, I think I would have waited to drill the holes and run the fuel vent lines until AFTER I micro finished and epoxy wiped the turtledeck.

You see, just above the top vent on each side the turtledeck is fairly flat in its arc around the top.  But right about where those vents are situated, the contour changes significantly with different curves and angles competing with each other, and trying to get those right, while trying to weave in and around those protruding vent lines just added to the challenge.  All in all I spent about 3 hours sanding and contouring the micro on the turtledeck and the shoulders.

After I got it all dialed in as best possible, I then added another round of micro to the divots and low spots, first on the left side (pic 1) and then the right (pic 2).  Moreover, note that I taped up the oil dipstick access door and added flocro into the gap around the door (some of us didn’t have that razor narrow cut starting out like the more consciences builders… ahem!).

A few hours later I popped the oil dipstick access door open and cleaned up the surrounding flocro filler a bit.  I also removed the tape from the door.  This is all in prep for epoxy wiping the top cowling here in the next day or three (depending on heat lamp availability!)

A sideline project I’ve been working on the past few days since I now have the canopy open is a positive block for the canopy’s air strut.  I had this on my list of things to do at some point after the bird was flying, but was reminded of it last week when I was helping my buddy Guy work on his Long-EZ.  His bird —built in 1982— has the original size canopy which is about half the size of mine, yet his air strut is one of the tall ones that is much stronger than the diminutive one I have on my canopy.

Clearly I’m aware that a good gust of wind on this massive “boat sail” of a canopy I have could easily bring it crashing closed, hopefully not on any unsuspecting head or fingers (almost certainly MINE!).  So I figured now would be a good time to get this canopy air strut safety block ginned up to get into the habit of always putting it in place, even it’s “only,” say, my fuselage sitting outside my shop.

I had envisioned a clamp style positive strut block, somewhat like the potato chip bag clip that so many canardians use for their rudder gust locks.  And I actually looked around for one at a couple stores over the last week, but oddly couldn’t find any full sized ones.  Thus, I decided to go much simpler and try out a style of strut block that simply snaps into place around the canopy strut’s inner shaft.

It took about 3 iterations with small test 3D prints to get the wall thickness and circumference angles right for a good snap into place on the canopy strut shaft, to ensure it always snapped firmly into place and was nicely secured on the strut.  With my lateral dimensions good, it was time to create a full length block for a height (vertical) test.

After all that was successful, I printed the first actual canopy strut block that you see here.

The functioning and dimensions of this version are great, with it having a good snap on pressure and removes with not too much effort either.  The issue is the holes I created to give it somewhat of a gun rail appearance.  With a sharp 1″ closing of the canopy to test how it would hold, it cracked this unit at the narrow top support above the top opening.  In response, on Version 2 I removed those thru-holes and simply added some labels on each side.  I also added some thickness to the spline down the middle.  I kicked the print off as off this writing and will grab some pics of my new version and ops test tomorrow.

Pressing on!

Over the past few days I’ve been focused on the top cowling, the aft strake interface with the top cowling, including the shoulders.  This was all in prep for micro finishing the turtledeck.

After a couple of cycles of removing and re-mounting the top cowling, along with a good bit of work refining and shaping the micro on the shoulders, I taped up the side edges of the top cowling to allow me to add flocro along the interfacing edges of the wings and top cowling.

In the end, I only added flocro to the forward 2/3rds on the right wing side, as can be seen above with the tape.

Months ago I filled a depression on the left side of the turtledeck with strands of UNI tape and an overlying ply of BID.  There was a depression on the right side of the turtledeck as well, although it wasn’t as prominent as the left side.  I had debated just filling that depression with micro, but finally decided to just mirror the left side with some strands of UNI in the trough, then an overlying ply of BID.  I then peel plied the layup.

After another removing of the top cowling, and the side tape, I then cleaned up the right side flocro before taping up the front edge of the cowling and aft bottom edges as well before remounting the top cowling.

With the top cowl mounted and the front edge taped up, I then prepped the turtledeck for micro.  I had originally planned do this with the canopy aft edge taped up and the canopy closed and locked, but since I don’t have the canopy latch system completely sorted out yet I simply pressed forward with the canopy open.

With everything prepped, I then whipped up some micro and applied it to the turtledeck.

I have one more decently warm day tomorrow before the weather turns chilly again for the next week.  I do plan on machining some stuff and creating some 3D parts during the upcoming chilly weather.

Pressing forward….

I’m still slogging along in this chilly weather spell trying to get as much done as possible… admittedly, my plane-building output isn’t nearly what I want it to be, but I am knocking out some of the more mundane, albeit somewhat challenging, tasks as I slowly creep towards getting this bird finished.

Today was all about finishing up the front corners and TDC CAMLOC holes on the top cowling.

I started by drilling out the center holes wider out to their original diameter on all the holes being worked, to allow for CAMLOC installation.

I then spent a good little bit grinding and sanding down the tops of the G10 “washers” on the right front corner to be even with the top of the surrounding micro, as they were a bit proud by around 0.015″.

After drilling out the center of the front left CAMLOC hole, I did the same thing by thinning down the carbon fiber “washer” to make the top even with the surrounding micro.

On the top CAMLOC hole —after re-drilling the hole— I trimmed the edges of the laid up carbon fiber and then shaved its height down a bit as well.

With all the “washer”/fill heights good (via eyeballing from the side) I then whipped up some micro (heavier on the West 410 than before) and filled in the gaps around the floxed in place “washers.”

I then filled the perimeter of the added carbon fiber plies on the top center CAMLOC hole as well.

I spent nearly another hour sanding down all the dabs of micro/West 410 that I had applied to some divots on the strakes, as well as quite a few on the right upper winglet. I also sanded down a couple of minor strake-wing seam fills as well.

Tomorrow is forecasted to be rather chilly again, so I’ll continue to do what I can with localized heat (aka heat lamps) since keeping those kerosene torpedo heaters fired up is not only loud and a bit smelly, but also fairly expensive when used day in and day out for heat.

Pressing forward! (slowly)

On the days that the weather’s been warmer I’ve been working on a sideline project to build a wing removal and installation lift, since in the very near future the wings will be coming off the plane.  I looked around for ideas, not surprisingly finding the best ones on the COBA forum.

I’ll note that a fair number of wing removal/install methods listed on the forum involved using an engine hoist hovering somewhere above the wing surface… which is only inviting trouble in my book, with a heavy arm and chain hovering over a painted fiberglass/foam wing.  No thank you.

So the best wing lift (and to be clear, NOT a storage dolly) I found that works for me is this triangular contraption.  After some assessment on how to construct it, I tweaked the design a little bit to make it collapsible.  I’ll further note that one of the main features I like about this design is that all 3 corner heights are independently raised or lowered via wheeled trailer hitch jacks.

So here is the near-final assembly of the wing lift.  I’d say it’s about 80% complete as I need to swap out some hardware and add the padded cross supports on each end that interface with the bottom wing surface.

I made the short end and one long side collapsible with hinges, with the other long side un-collapsed, that simply bolts onto the 3 expanded segments when they’re set in the expanded position.

I’ll note that today was warm during day, but the weather was being a bit sneaky as it is still rather chilly at night.

Back on the planes… On the left front corner of the top cowling, with the thinner micro application, I used my micrometer to measure the micro.  Instead of using the 1/16″ thick G10 “washers” as I did on the right side, I scrounged through my carbon fiber scraps and found an acceptable thickness for this CAMLOC hole.

I then floxed and clamped the carbon fiber “washer” into place.

On the top center of the top cowling, I only needed 0.02″ to 0.03″ added thickness around the CAMLOC hole.  Instead of trying to add a “washer” or disc of some other material, I simply laid up a 2 full and 1 half ply layup of carbon fiber.  I then of course peel plied the layup.

I also spent a good 45 minutes cleaning up the outboard strake-to-wing seam, doing a flox fill on the right wing edge.  I then identified a few other minor divots that needed tending to, which I will knock out tomorrow.

I’ll continue to nug through the minor fills and cleanups, get those knocked out, and press forward with completing the finishing of this bird.