« Archives in March, 2009


1 hour.
Havent’ had a lot of time to work on the plane lately.. crunch time on Terminator 4. I’m not putting in a lot of overtime, but there’s some, and there’s just enough to make me not want to do much of anything after the household tasks are done, which seem to be growing in number. But this morning, I made all the fiddly brackets for the subpanel. The ones on DWG 24, I had to pull from the preview plans, as i can’t find DWG 24 anywhere. I might have purged it when I saw that it was for the slider canopy. I did manage to drill the hinge brackets to the subpanel, but that’s as far as I got. And I’m very quickly running out of things I can do without painting the interior and all the assorted parts. Maybe I’ll get a paint day Sunday, but my schedule is currently at the whim of Skynet and its metal minions. Oh, and my bathroom sink is clogged again. Shelley, home from work on an extended vacation, tried to help out by freeing up the slow drain in the downstairs bathroom. Not only did she stop it up completely, but the plunging process has now half-filled my sink with noisome black liquid. So that’s going to be my Saturday, assuming I get one.
Even my dreams are filled with Terminators and broken plumbing.

Full Scale != Accurate.

1 hour.
Deburred some F-703 notches, then clamped the angle to the panel for drilling. Guess what. Even though the drawing says “Full Scale” on the detail for the notches in the .063 angle, the part as shown on the drawing isn’t drawn accurately to those measurements. What I did was mark a line on the angle, then placed the angle on the drawing and marked the notch cutout marks from where they are on the drawing. DO NOT DO THIS. The measurements called out are reliable. They will put the notches exactly beetween the holes pre-drilled on the panel. The notches as shown on the drawing aren’t even close. All the notches must be measured out as spec’d. Now I have to make a new one. Problem is, i’m out of .063 angle, so I’ll hit up AC Spruce when I’m done here.
In all fairness to Van’s Aircraft, there was probably something I read long ago in the construction manual about referring to measurements rather than the picture itself, but I don’t remember it. The more I think about it, the more it makes sense from a layout point of view, but dammit, when something is described as ‘full scale,’ I tend to interpret that to mean ‘full scale.’ Silly me. Now I know never to trust the picture, but always reference the actual measurements. Grr.
Regardless, I’m not going to get to it this weekend. I have to retrofit the doghouse as a chicken coop and help Shelley get ready for her chicks to arrive in the mail.

Panel reinforcing angle

1 hour.
This went surprisingly quickly. The full-scale drawing of the F-703B angle was a big help. I was able to mark off the notches by laying the angle down on the drawing and marking everything. Of course, you should check, because there’s another ‘full scale’ part on that same drawing that’s 1/2″ longer than the stated dimensions.
The panel reinforcing angle is made out of .063 , and it stiffens the panel. Notches need to be cut into it along the length so it can bend around the curved edge of the panel. I haven’t deburred it yet, that’s another fun adventure waiting for me.

Seal support angles.

1.5 hours.
Picked up where I left off this morning and finished making and drilling the side seal support angles. That’s it! woohoo!
Not sure why that took so long. Oh, I know. It’s all the deburring of the notches.

subpanel work

1.5 hours.
Fabricated and drilled the center seal reinforcement angle. This goes on the center subpaneln and helps seal… Something. This is the first time in the kit where I’ve had to learn the technique of notching aluminum angle to bend around curved shapes. Not that big a deal, really, but it’s a good part of the subpanel work. Basically, you make some holes in the angle near the edge, then cut notches tangent to the hole edges, giving you a rounded notch. This allows you to bend the angle around a curve, which needs to happen on the subpanel, and later, the panel. It’s pretty cool, but it makes for a lot of deburring work. I got the center one done, and cut the length of one of the side ones, and I’ll try to finish those tonight after work, although I’ve just been informed I’m putting up shelves.

The Dreaded To-Do List

Every so often I start getting that spread-too-thin feeling on this project. Too many things unfinished because they’re dependent on other things, and sometimes, the genuine chicken-and-egg scenario. I’ve also got a whole lot of ‘blow that off until you get to the airport’ type jobs to do that usually come about due to lack of space or lack of helping hands. After yesterday’s autopilot fun, I decided to make a list. I’m going to do it here, so bear with me if it goes fractal and sounds like Ginsberg from time to time.
What i’ll do is list what I have to do, then list the excuses for why I haven’t done them. Sound good?
We’ll go by subkit and make it easy:
fiberglass tips – Can’t do that until the final elevator balancing is done, which needs to be done with everything rigged.
strobe/position light wiring – No excuse for this at all, just haven’t done it. Need to do the fiberglass work as well.
trim servo cotter pin (yeah, this is an easy one, I know) – I just have to do this one.
trim servo wiring run – I may have hosed myself on this one. I’m not sure exactly where/how to feed the servo wiring from the servo to the root of the emp so it can run forward to the cockpit.
body filler/damage control – The empennage is where all the early mistakes got made, so there’s some ugly stuff I need to plaster over with body filler. An extra hole from a badly placed dimple die while dimpling for the stiffeners, for instance
wingtip wiring connectors, nav antenna wire – I’m storing the wingtips on the overhead ledge. I filed this task under ‘airport.’
Autopilot servo – My clever conduit interferes with the bracket. I now have to take a section of conduit out and route the wires around the bracket/servo assembly. See yesterday’s entry.
closing the wing skins – Airport or right before. I’m not closing those up unless I’m absolutely sure I won’t need to get in there again.
Autopilot Pitch servo – Just haven’t done it yet. Need to fab bracket and make pushrod, but I can’t do this unless the elevators are rigged and neutral. I just took the emp off so I could move around the shop again.. I should have waited. Whaargarbl.
Rudder cables – need to paint the interior before I run those cables.
Brake pedal support – need to paint it and paint the interior. first.
Firewall recess – waiting to see if I do or don’t need to reach my arm through that hole to buck something (lame)
Fuel lines – Need to paint interior first.
Subpanel, panel and canopy supports – in process now.
Finish kit – Everything.
Well, that’s all I can think of for now. I’ll probably edit this as I think of new stuff.

Fun with the Autopilot.

1 hours.
Yesterday my package from Trio Avionics showed up. W00t! This morning I started installing the roll servo in the right wing. I found out two things. One, I need a proper crimping tool, because now I’ve gone and killed the ground wire lug that’s supposed to attach to the mounting bracket and two, The servo and the bracket don’t fit, thanks to the position of the wiring conduit. Observe:
You’re looking at the left wing, but the right wing is set up the same way.

This is an image of the servo mounted in the Trio Bracket. Image is from the Trio website.

The trim servo bracket protrudes up far enough to interfere with the wiring conduit. So now I have to remove a section of the conduit, secure the ends, then route the wiring around the servo while protecting it from friction. Of course, this will solve the problem of cutting a hole in the conduit for the servo control wiring. Another option is to send the bracket back to Trio and fabricate something that allows the servo to sit flat against the spar. But this method involves drilling the spar, and I’m going to avoid that if at all possible. The third option is to install the servo in the wingtip. I can use the bracket, and it’s OK to drill the spar out there on the end of the wing. Of course, that means I have to fabricate a long servo pushrod from wingtip to bellcrank as some have done for their RV-6 retrofits. Still another option is to put it under the seat floor, which has the advantage of accessible wiring, but I still have to make a pushrod from there to the bellcrank. Of all the options, removing a section of PVC conduit in the wing seems like the least painful, depending on how many contortions the wiring has to go through to get around the servo. Even so, there should only be a strobe cable and position lights going out to that wingtip; the Archer comm antenna is in the other one. The other question is, how far up into the conduit does that bracket protrude? And can I notch it without compromising the integrity of the bracket or the servo? This is a question for Trio, since I’m not about to go hacking on a $750 module without very specific approval from the manufacturer.
Originally, i had no plans for an autopilot. But things change. The Trio servos work with the MGL Odyssey, and since that’s going to be my EFIS, why not? The good news is, I haven’t closed up the wings yet. The bottom inboard skins are not yet riveted on, so I have lots of room to work.
Oh well, at least I can work on the pitch servo.

Finished Roll Bar and other stuff.

4 hours.
Finished the roll bar! Booya! I drilled the roll bar to the F-631D angle, after all that measuring from last time. A couple of goofs, but not too bad. First was that I trimmed the radius for the angle bracket a little high. I had to abandon the lower hole in the F774 skin ear where it attaches the skin to the angle bracket, because the 1/8 hole didn’t have the edge distance required. I had to do this on both sides, actually. Kinda bummed me out, but a little filler and you’ll never notice. The other thing I did was drill out the lower forward hole on the right to #19 instead of tapping it to 8-32. Duh. So I’m going to put an AN-509-10R10 bolt through there and lock it down with a stop nut. Everything else is fine. I got my edge distance for the 8-32 screws and the 10-32 screws on the aft section of the roll bar. I also didn’t have to remove much metal to follow the curve of the longeron where the skin lays against the angle bracket.
This is the left bracket bolted in.

And this is the right one. Not that you can tell with me shaking the camera like I’ve got a jackhammer in the other hand.

This is where things got a little odd. The cutout for the roll bar is a little high. Not terribly. And yes, these corners are radiused.

After getting everything drilled in and bolted up, it was time to finally install that support channel thing, and I can’t remember the number of it right now. This gets drilled to an angle on the back of the roll bar, and it connects to the next aft bulkhead. The back half of the canopy plexi goes over this. Others have put baggage compartment lights, in this part, but my interior lighting is going to consist of what’s necessary to see the controls and instruments, and not much else. I think a LED flashlight velcroed under the armrest would make a fine baggage compartment light. I don’t want to wire anything I don’t have to.

This shot just shows the AN3 bolts on the inboard left holding the roll bar to the angle brackets. Oh yeah, I had to trim away a smidge of the seat back stop for the angle bracket to sit flush.

After that, I went on a mad cleaning spree. I rounded up all the loose hardware that had fallen on the floor or in the belly of the plane and returned all the tools to their proper places. I vacuumed 2 weeks’ worth of metal chips off the floor and a load of aluminum dust off the grinder/saw bench. Then I vacuumed out the plane,
Clean shop:

Clean ship:

After that, I tied up some loose ends. The forward-most bulkhead in the tailcone comes from QB-land with pop-rivets installed in the joint between the two bulkhead halves. I guess this is for better skin fit or whatever. Plus, the plans tell you to leave the bottom hole open if you’re building a sliding canopy. Well, I’m not building a slider. So I was able to get those done.

The other thing I got done today was something I should have taken care of when I put the control column together, but for some reason, I blew it off. I drilled the hole in the control column for the right-side stick. There’s a bolt through there, but it’s not going anywhere without horking on it with something that’ll chip the powder coat, and besides, I don’t see the point of taking the right side stick out anyhow. Maybe if shelley decides she doesn’t want the thing in her lap while she knits on long XC flights, then I’ll revisit it, but for now it’s there.

The last loose end I took care of was the rest of my finish kit inventory. I still have to do all the little bags, but I got everything checked off the list. This is most of my finish kit, occupying the guest house bedroom.

Roll Bar/Cabin Frame

1.5 hours.
Not sure what to call that thing. Cabin frame, roll bar, dunno. That upside-down U-shaped thingy that keeps your head from snapping off in a rollover. I made the cuts for the radii of the F-631D angles and got everything lined up for drilling. This was one of those things I needed to get absolutely right, so I spent a good long time measuring, double checking, measuring, clamping, and finally marking where the angles will go. I sort of used Mike Bullock’s method, where I clamp the roll bar to a straightedge clamped to match the angle of the front of the skin ears. Mine was a little different, in that I kept the roll bar on the whole time instead of using pieces of equivalent thickness, then marked the outline of where the angles lay. This will get me where I need to be for drilling, although i might try the other way when I get home, since I haven’t committed to any holes yet.

Cabin frame. Again.

1.5 hours.
stuck the F-631D angle brackets together and started getting them lined up on the fuselage. Van’s says the roll bar is supposed to go 56 13/16 back from the ‘fuselage station’ which in this case, means the SS firewall. Well, that’s nice and everything, but my ship is a quickbuild, and where the holes on the F-774 skin line up to the roll bar and have good edge distance is about 57″ and small change. This gets the F-631D brackets into the big angles under the baggage deck bulkhead with enough clearance for the nuts that hold down the brackets, roll bar, etc. What was a very pleasant occurence is the way the roll bar itself all came out. For a quick and dirty test fit, I clamped the angle brackets down with the outer bracket at the edge of the longeron, right where it’s supposed to go. The roll bar goes on these without much trouble, but I can see having to stretch it just a hair to pull it into line. Next thing is going to be drilling the brackets to the bulkhead, then drilling the roll bar to the brackets, using the foremost aft top skin as a drill guide and lineup tool. Yarr.
Stay tuned for the attaching of the roll bar.