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More control cable work.

December 20, 2012 / posted in Firewall Forward / No Comments

9 hours.

I owe you a report from the last two sessions, which were on 12/1 and 12/2, and 12/15 and 12/16. The week of 12/4, we went to Florida for vacation, and nothing got done. Upon returning, I did some work on control brackets. Turns out my fancy bracket that I made for the purge valve cable isn’t going to work, because there’s no threaded part where the engine-side end of the cable is. What I’m doing is using a piece of angle, which will allow me to hold the cable in place with an Adel clamp.

The other thing I did was fiddle around a lot with cable routing. Supposedly the 51″ and 52″ cables from Van’s should work for the mix and throttle, but I wasn’t exactly sure about that, so I ordered the 60″ ones. Those, I’m sure, can be routed to where they need to be on the throttle quadrant. On the engine side, it was pretty interesting. I wish someone had told me I could have had AFP reverse the mixture direction, because if that had happened, there’d be no danger of interference between the cables, arms or hardware. Maybe on the next plane I build. Lol. Anyway, I was able to find positions for the cables that allows the arms to move freely and not interfere through their entire range of travel, and that’s a good thing. Unfortunately, I’m looking at running those things fairly close to the exhaust pipes, so good thing I’ve got heatshields, both the solid kind that clamps to the pipe and some of the cloth-type stuff that can wrap around the cables.

With that solved, it was time to make some bracket, which meant more steel. I’ve more or less made my peace with steel, other than the fact that it burns up bandsaw blades like crazy. I first mocked up the brackets out of .032 aluminum, just to get the angles and holes right, then hammered the mockup flat to use as a template on the steel, which reminds me: Superior Air Parts, you bastards, why couldn’t you have made the bolt spacing for engine brackets on your cold-air sump the same as on the Lycoming sumps? Huh? If it wasn’t for that, there’s a good chance one of the stock Van’s brackets would have worked.

It wasn’t all bad, I was able to obtain a PDF of the dimensioned drawing of the bottom of the sump, and from that I was able to drill the mounting holes in my fabbed steel brackets fairly easily. Of course, I didn’t have any of the hardware necessary to attach anything, so I had to make a fairly severe ACS order. In that order, I got 3 more of the firewall eyeballs (which I’ll have to drill out to fit the fat green marine-style Van’s cable), a bunch of rod-end bearings, and some other bits and pieces, including the 2×1/8 angle I’ll need to fabricate the quadrant-side bracket. If I can ever get away from work, the remodel, and my recovering dog (long story, and not a good one), I should be able to finish up the control systems.

Oh, and I’ve also ordered all the hoses I need from PHT, so I should be able to rock out all the engine plumbing as well.

Control, I’m Here

November 24, 2012 / posted in Firewall Forward / No Comments

7 hours.

Yes, I’m using a Nitzer Ebb track as a title. Yesterday before the grand face-stuffing of Thanksgiving, I fabricated the bracket for the purge valve. I don’t work with steel much, but 14ga hot-rolled sheet steel isn’t too bad. My bandsaw blade would disagree, I think it’s just about shot. I also killed my grinding wheel. Now that I’ve used it on steel, it’s useless for aluminum. But that little exercise has taught me not to fear steelwork. Not too much at any rate.


Here’s the bracket. The cable goes across the engine to work the purge valve arm.

So today was all about measuring for control cables. Van’s has a 60″ push-pull quadrant cable that should work for throttle, mix, and prop governor control, and ACS has a button-lock cable that should do for the fuel purge. I needed a 65″ cable for the purge, but ACS doesn’t sell one less than 6 feet, and I don’t feel like having a custom cable made for that stupid thing. I’ll make a 72″ cable work.

I also went into a mad panic thinking I’d forgotten to write down the wiring map for the AP servos. I looked for the Trio/MGL wiring instructions for about two hours, because I seem to remember writing the servo-to-cable-to-DB9 colors and positions down on it. I couldn’t find it. After looking everywhere, and thinking I was going to have to reverse-engineer the wiring from what I could see in the clear-shrink-wrapped bundle on the pitch servo.


But no. I tacked it to the wall above the workbench and didn’t think to look there.

With cables measured, I measured the lengths for the remaining hoses I need. I need one for oil and three for fuel. I put in a quote request to PHT, hopefully they’ll be able to turn them around fast.

More bits and bobs

November 18, 2012 / posted in Electrical, Firewall Forward, Panel / No Comments

5 hours.

Since we’re now undertaking a remodel of the downstairs (as if it’s not crazy enough around here) the pressure is on to get the plane done and get it out of the guest house. I’ve been finding all the fiddly things to do and doing them, per last week’s list.

The alt air cable adventures continue. The bracket’s done, and now there’s a hole in the firewall. Suck part is that I have the wrong eyeball, I need the .188 and I have the .210, so it doesn’t actually seal much of anything. New one is on order. I reinstalled the flap brace and drilled the horizontal stabilizer to the the fuse. I had to do this because I replaced the HS-710 bracket a while back because it was crap and I never got around to it.

The panel is also labeled! This is quite nice, but I still need to put the N number on it, as well as the placard that says, “I built this plane, so don’t go looking for certification.”

Cooling blast tube for the alternator is installed, but only halfway, it needs to be secured in such a way that it blows on the alternator. Other blast tubes need to be installed for the magnetos, and then I have to get serious about hoses and control cables.

FWF Sensor Wiring DONE!

October 29, 2012 / posted in Electrical, Firewall Forward / No Comments

10 hours.

This is yesterday and today. Yesterday started with an epic shop cleaning. I have those every so often, and it’s helpful, extremely good to have a workbench devoid of clutter, if only for a little while. Stuff got put away, stuff got tossed out, floors got swept and vacuumed.

The fiddling with the FWF stuff has been progressing as well as I can make it, and the wiring has been a bit of a challenge, especially since the K-Type wires on 2 of the sensors were too short to make it all the way to the RDAC engine monitor module. Then there’s the business of where to actually run things so they don’t rub on other bits or get roasted alive by the exhaust pipes. I got the current sensor done, although I suspect I’ll have to flip it over, I got all the temperature sensor wires run, wrapped, and grounded. About the only thing that didn’t happen is the MAP sensor, which needs a 1/8″ to 1/8″ barbed elbow fitting. Searches have turned up no such animal so far. But technically, that’s not wiring, so legally speaking my FWF sensor wiring is done.


Here’s the beginning of the attachment process. The overbraid K-type wires are a ratbastard to work with. They’re a little like shielded cable, but they’ve got an extra woven sheath below the braid that absolutely sucks to try to get off. Maybe there’s a trick to it, but this was by far the worst suckage of this task.


A slightly different angle. On the RDAC (the grey box), the first 4 pairs are exhaust gas temperature thermocouple inputs. Can’t change them, which kind of sucks, because then I wouldn’t have had to extend a couple of TC wires to make them reach the proper input. Oh yeah, splicing TC wire sucks too. The ty-wrapped snarl at the bottom is the FloScan fuel flow sensor wiring. I installed the FloScan months ago, but never got around to properly wiring it until today.


Still a rat’s nest, but there is progress there. This is right after grounding all the things that needed grounding, being the FloScan, the tach sensor, and the RDAC itself. The EGT and CHT probe wires haven’t been cut to length yet, nor have they been secured by Adel clamps to the firewall.


Ahhh, that’s better. Still some wrapping to be done, but all the wiring is secured and attached.


This shows the oil pressure sensor hooked up and run into the bundle. This will benefit from a couple of Adel clamps attaching the main bundle to the engine mount, but we’re in a pretty good place.

Even more fun: Once I got everything wired, I fired up the EFIS and decided to test out whether or not I’d actually inserted the right wires into the right terminals on the RDAC. This was done by means of a heat gun and a blowtorch. The heat gun raised the temperature of the actual cylinder itself so I could check the reading on the EFIS. The blowtorch was for the EGT probes. Suffice it to say that the method of testing was a great success: I found I had miswired the 1 and 3 cylinders for EGT, and the 2 and 4 cylinders for CHT. It is now all fixed.

Some sensor wiring.

October 4, 2012 / posted in Firewall Forward / No Comments

1.5 hours

Tonight I was able to do a little more work on the engine sensor wiring. Mostly it was about figuring out routing and wrapping hi-temp spiral wrap around probe wires, which is such a chore. Not as bad as Adel clamps though. I have to figure out the technique for those, because they’re killing my fingers. Anyway, the major visual effect achieved tonight is now the plug wires don’t hang out the bottom like sword-slashed entrails. I also got started on wrapping/routing the probe wires, but the wrap will have to come off because I forgot about the MGL current sensor that’s supposed to go on the alternator wire. Grmp. I also had to splice one of the EGT wires, because it was too short to make it all the way to the RDAC. I’m a little concerned about that. Oh, and I have no idea what wire goes to which cylinder. Yep. Awesome, that’s me.

I’m sick of this airplane. My wife is REALLY sick of this airplane. I need to get it done, and soon.

Cowl surfacing, part 2.

September 10, 2012 / posted in Firewall Forward / No Comments

6 hours.

Before I knew anything about fiberglass, I figured the pepto-pink Van’s cowl was pretty much the norm. It’s not. The Van’s cowl is shite. You’re supposed to fill in all the pinholes (and the whole thing is mostly pinholes) by rolling on straight epoxy, then squeegeeing it off. 3 coats go on like that and theoretically, the pinholes are filled in.

The reality is far from theory. What I’ll have to do now, if I want this thing to be even remotely smooth, is to squidge on a layer of micro slurry. Not the paste used for building up a shape, but enough to fill in all the divots. Once that’s done, I’ll be able to sand it smooth, then seal it with another layer of resin.

Or, I could take it to a body shop and have them do it. I need to be very careful not to bust the 51% rule, though, since I got the quickbuild kit to start with.

So the third coat of resin is curing right now, and should be ready for sanding tomorrow.

Since I was in fiberglass mode, I finished the cutout I had to make in the snorkel to allow it to clear the alternator. This is also curing, and should be done enough to permanently install tomorrow.

Aside from that, I reworked the fuel feed line so it makes a little more sense and doesn’t bend at such an extreme angle on the input.

More fiberglass fun – Cowl and baffles.

September 4, 2012 / posted in Firewall Forward / No Comments

4 hours.

Not a complete balls-up, no, but close enough. Yesterday I finished the lower cowl inlet baffles. Almost. I still need to cut away some extra airseal that blocks a portion of the snorkel intake, but other than that, I’m done with airseal. I hope. That’s the good news.

The not so good news is that I decided to move on to filling the pinholes in the pepto-pink lower cowl. Of course I cocked it up, because I failed to remember one simple thing: The resin mix is supposed to be applied to the surface with a squeegee, not just slathered on with a brush. I should also have cleaned the surface with acetone, then soap and water before applying. So now I get to sand off a bunch of resin and redo it. Fortunately, I didn’t do the whole thing, just the front third, but it’s still a pain and a lesson in attending to detail.

Since that was going to have to wait for another solid block of time, I decided to finish the heat muff install. When I received the heat muff, one of the lock nuts on the through-rods didn’t have threads in it. I got some replacements from the manufacturer, and that is now installed. I also cut and attached the SCAT tubing to the muff, the heater box, and the baffle vent. OK, that last part still needs to have the hose clamp tightened, but it’s pretty much done.

Cowl and foam

July 29, 2012 / posted in Firewall Forward / No Comments

4 hours.

Yesterday I glued the sub-ramp I made the day before to the cowl. Today, I shot my marine foam into the space underneath the ramps in preparation for glassing in the sides and blocking travel of high pressure air through the spaces underneath the ramps to the low-pressure area to the sides and below the baffles.

I may have used too much foam. It just keeps growing.

Tomorrow I’ll carve out the excess foam and glass in the tunnels.

I also took a crack at filling the area around the oil door. This might turn out badly, but it’s just resin and micro, so I can always sand it off and start over.

Cowling ramps

July 26, 2012 / posted in Firewall Forward / No Comments

2 hours.

This is two hours of puttering over the last several days. I go the cowl ramps glued on, and tonight I made the contoured part that interfaces with the governor baffle. Next is to fill the cavities under the ramps with boat foam, shape them, then glass them over.

Gluing the ramps on turned out to be more or less a non-issue, but I did have to take the front baffles off, which is a PITA.

I got my ignition harness back from Bill’s Air Center. That was only $80 worth of stupid, so I consider myself lucky. Oh, I didn’t tell you about that? OK. I was pulling on the wire end of one of the starboard plug wires at the harness cap, for some reason, and it slid out of the casing. Plug wires work like a Chinese finger trap. The outer shield expands or contracts depending on where the tension is, so it allowed a bit of wire to slide out of the casing. One thing led to another, bad went to worse, and the next thing I know, the whole wire is in its separate components on my bench.

After a frustrating couple of minutes, I resigned myself to taking it up to Bill’s Air Center at SMO. Bill’s a great guy and he’s been there forever. They fixed it, but said it was a major headache to source all the parts, since Skytronics doesn’t actually sell them. They want you to send your harness back to them for repair. Phoo on that. Anyway, it’s all better now.

Baffles 15 – Almost done!

July 7, 2012 / posted in Firewall Forward / No Comments

6.5 hours

Today was fairly significant, even though it might not look it. I finished attaching the airseal material to all the baffles, drilled the holes for the spark plug wires, and more or less permanently attached the baffles to the engine.


Since I did the aft left baffle last time, I figured I’d do the aft right baffle, that way I could at least get both of them on and done. this one actually proved to be pretty easy, with no surprises. After all, it was more or less about doing the spark plug wire grommet holes, deburring everything, and attaching the airseal with rivets.

The connection in the middle where the baffle connects to the bracket got changed a little. Originally, I had the bracket pinning the airseal between it and the baffle, but that looked stupid and distorted the baffle, so I cut some slits in the baffle to get around the bracket. It should seal fine, and eventually the rubber will mold itself around the bracket with hours of heat and use.


With both sets of aft baffles on, I installed the oil cooler. This was one of the items that’s been bugging me for a while, and now it’s finally done. I’m still not happy about the amount of flex in the aft baffle where the inboard oil cooler attaches, but I’m not exactly sure what to do about it right now. Any reinforcing strut that picks up a convenient attach point on the engine would interfere with the fuel injector lines, which is no good. This shot shows the beefy angle bracket I installed last time to reinforce the connection between the side and rear parts of the baffle, and gives the oil cooler bolts a more solid structure to hang from. Lots of people report problems in this area, but this, and a strut for the other side usually fixes it.


So here it is, the bane of my life, nearly finished. I recut the governor baffle, because the governor hole didn’t seal well enough for my taste, and this time around, I left a big dog-ear flap on the front to aid in sealing with the cowl, should the need arise. I didn’t take a lot of photos of the process of installing the governor baffle seal, because it’s difficult to shoot pictures while you’re using both hands to wrestle with airseal. The end of the governor is bigger than the housing where the seal sits, so you have to cut the hole big enough to get over the end, but small enough to seal on the governor housing.

This process also revealed a small flaw in my governor baffle design: I can’t actually take the baffle off without removing the governor. I can live with this, I think. But what I have to do to get at the governor nuts is take the left front baffle off, which can’t be done with the governor and its baffle in place. But there’s always a way. It’s messy, and it’s a hack, but disconnecting the oil line from the #2 cylinder allows me to drop the left front baffle out of the way and slip it out past the governor baffle.

I also put the airbox on, just to see everything in place, and make sure it all still fits. What you see in the photo is essentially the final configuration of the baffles and intake.

I still have a few minor things to do. I need to drill the duct holes for the mags and alternator, but I don’t want to do that until I’ve figured out control cable routing. I also need to make the rods securing the baffles at the bottom where they wrap around the cylinders. Once that’s all set up, I’ll need to squidge some red RTV in where the airseal meets the baffles, and around the engine-baffle interface in various places, plus around the corners of the oil cooler so I get maximum efficiency from the airflow through that.

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