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RV3Bob 12-30-2021 09:25 PM

I caution anyone using your wifeís stove to dry or bake painted objects to ask her first and tell her it might ďsmellĒ for awhile. I did not. It works great but when I finished the whole house and especially her kitchen reeked with paint odor. She came home about five minutes after I finished. I got that ďyour in big trouble lookĒ. That was about 20 years ago and I still hear about that😳

Bob Grigsby
3B. Close. I think
Flying Cub on New Years

David Paule 12-31-2021 10:44 AM

I've been letting things dry normally until they are dry enough to handle, and then baking them. The smell is markedly reduced.

Also, my kitchen has an external exhaust fan so I can clear fumes well.

With those two things, it's a non-issue.

Some of you might have seen that the urban fire is near me. I'm unaffected by it although it's very close. I know people who had to evacuate; some returned but not all. I don't know how they fared. We had 105 mph winds after an extremely dry year. Fortunately the weather changed and now the wind is nil and it's snowing. Tomorrow will be in the teens and that too helps fight the fires.

Happy new year, everyone!


Foghorn 12-31-2021 12:13 PM


Where did you get the Tail Lynx cables and springs? They look very nice and streamlined. I did a search and it looks like Vans sells them. However, I canít find them in the Vans store.


David Paule 12-31-2021 12:50 PM

I bought them from Van's back when they still made them.

My general policy on this project has been that if something is made by a small vendor, buy it early in case they go out of business or retire. These fell into that category, as did the Vetterman exhausts and the Robbins Wings cabin heating parts. There were probably some others.


Foghorn 12-31-2021 02:03 PM

Thanks Dave

David Paule 01-03-2022 12:18 PM

Before I started drawing up wiring schematics, I had to make some fundamental system architecture decisions. I wrote down my thoughts at the time, and have been doing the system work based on that. I came across this in my notes and thought it might be worth including.

My goal is day VFR. Big caveat, I am not including an upgrade path to eventual IFR, although I will incorporate ADS-B compliance as part of the initial installation.

1. My ignition uses self-powered sources (can be magneto or P-Mag, with P-Mags installed) and is redundant. With the same equipment on both left and right, though, these are similarly redundant, not as good as redundant by different means.

2. The fuel pumps are redundant, since there is both an electrical and a mechanical one. These have different modes of failure.

3. The fuel filter, a gascolator, is a single-point failure mode in series with the pumps. It's located inside the engine bay inside the thermal and fire envelope of the region.

4. With both the standard air intake and a carb heat system, the engine will have separate sources for intake air.

5. My basic electrical power source is redundant, with both a single alternator and a single battery. These are differently redundant but are connected to the same systems and connected to each other, with interconnected modes of failure.

6. Navigation will be differently redundant too, with an iPad primary and the EFIS secondary. The iPad has its own battery and in normal operation will be charged from the aircraft. If the power fails it'll retain several hours of power itself.

7. The airplane will have minimal basic lights and will be marginally capable of night flying. The main purpose of the lights is for daytime mid-air visibility. Night flying goes beyond my planned operations but the capability adds contingency operation. In-cockpit lighting will be with a headlamp.

8. The airplane will have an analog airspeed indicator. I feel that I can judge altitude over the ground well enough to stay safe if the EFIS dies, and there will not be an analog altimeter.

9. The airplane will have a stall warning system much like my current airplane does. It's a single-point angle of attack indicator. If electricity remains, it should function. It's a back up and an assist to the EFIS or analog airspeed indication.

9. I think all else will be non-redundant.

10. I will only have a single com radio, a single transponder and a single ADS-B system. That should let me get back home to my non-tower field.


David Paule 01-21-2022 07:24 PM

Okay, you could be thinking, I closed earlier with a shop reorganization and then jumped straight to the panel installation, and then went rambling. What the heck? Well, the EFIS arrival let me do some more electrical things and some of them, like the canopy latch warning switch, the wing electrical connectors, and connect to the EMS once it's located, which is part of the engine installation. While the shop still has electrical tools and parts handy, it made sense to work on that aspect.

One of the things I did was revise the warning light wiring for the third time. It just wasn't right, to the point that I'd rip it out and redo it. The version shown has bene redone.

I rather hate to mention upcoming things - I much prefer to talk about things that happened. But one of the things that happened is a rough plan for the engine and shop. So here is a brief look ahead.

* Get as far along with the panel and electrical as I can without the engine.

* Bring the engine home.

* Install what I can on the engine before hanging it.

* Locate the firewall holes and drill those. Make the Fiberfrax and titanium overlay and install those.

* Finish the shop reorg. Can’t do it earlier because I need the current layout to work on the engine before I hang it. And I can’t go farther until it’s reorganized. This is one of the things driving the sequence.

* Bolt the engine mount and landing gear on. At that point, the fuselage can’t be easily flipped on its side or upside down without help.

* Install the engine and complete its installation, including the remaining electrical.

The bottom of the switch panel needed a few things, like the P-leads to the ignition and so on. I opened up the avionics shelf to have access. This is also letting me tie up the wire bundles. I took the opportunity to label the switches from underneath to make identifying them more sure next time. The photo was taken just after opening it up, before the labels went on.

It was easy enough, unfastening it and rotating it clockwise 90 degrees and laying it on the sawhorse. Once the wings are on, it’ll open 180 degrees and rest on some sort of a support.

Off topic - I live in Boulder, CO and sometimes manage some rentals. The recent Marshall fire did not affect my home or the RV-3B project, but it did affect several of the rentals. All survived and the people are fine. But smoke clean-up is on-going now, and dealing with that has been affecting my work time. A number of people locally were affected, and about 1,000 nearby homes were lost.

One of the things pending was to locate the ground tabs and the Dynon EMS. The ground tabs are easy: with the battery fitting into the right cowl cheek extension, the ground tabs will go inside the cabin at that point, high on the right side cockpit wall. But there wasn’t room for the EMS and it’s thick, stiff cables. There were three locations that I narrowed to two. The location that didn’t make the final selection was the back of the panel on the right. The EMS fits there nicely but that location would preclude using that half of the panel for anything that wasn’t surface-mounted. The panel is too small to accept that limitation.

The above photo shows one of the two final candidates, the bottom of the avionics shelf. This location has a few issues, too. Among them is simply that my knees are right below it. Another is that either the carb heat or the cabin heat cables will pass through the area.

The next photo shows another of the two final candidates, the top back of the firewall. This would interfere with some of the firewall-mounted stuff, since it’s the only firewall area free of the engine mount complexity.

Any suggestions?

That fiberglass tab on the right of the avionics shelf will hold a large snap bushing for the EMS network cable, the ground wires and the power cables. It's one of the things that's been going in.


David Paule 01-25-2022 06:43 PM

I went ahead with the EMS installation on or rather, off the firewall. The fittings support it a little over 3/4” from the firewall; I’ll be able to install components forward of the firewall at that location with a bit of paying attention to things.

The sensor cable will go out the righthand cowl cheek extension and the network cable will need to somehow wrap around the EMS and go to the avionics shelf via the right side.

The pitot tube from the left wing is 1/4” plastic tube, pretty standard stuff. Then I switched to 1/8” plastic tube and this is much easier to work with. However, I didn’t want to replace the tube in the wing so I needed a way to reduce the 1/4” tube to 1/8”. Since the tube to the ADAHRS and the tube to the airspeed indicator all meet in the same area as the 1/4” tube, some sort of fitting was needed.

This photo shows my two choices. The blue fitting with the tube connections weighs about 34 grams, and the plastic fittings collectively weigh about 11 grams. This was a no-brainer; I’m using the plastic.

I made a list of all the grand connections that the ground forest of tabs will need to accept. I already have the forest of tabs and it ought to have ample tabs. Three seemed misplaced but with a bit of thinking I found two of them, and then by digging, I found the third.

The after-market network hub by Gil Alexander is pretty nifty, but the plug-in Molex connector hadn’t checked out. It was the only thing that hadn’t. With some time, I replaced and reset the pins in it, and now it all checks out. Incidentally, that hub contains the ground and power leads from the servos so they don’t need discrete hookups, a definite convenience.

I sort of enjoy working with standard Dsub fittings but Molex connections are a real pain. And I have another unrelated one to go.


David Paule 02-09-2022 01:11 PM

The electrical wiring is as far along as I can get without installing the engine. Every wire has been checked and tested. All the cables except for the EFIS 37-pin cable, the CHT/EGT cable, which are both factory-made and the cables already in the wings . The cables permanently attached to the fuselage have been checked and tested. Since the ground forest of tabs is not yet installed, none of the electronics can be connected to power yet.

Ryan Courreges, climbak here on VAF, had offered to help with the project. He helped with the car shuttle to get the engine and engine hoist home, thanks, Ryan!

Once we got the hoist reassembled and rolled the engine into the shop, we found a possible difficulty that I hadnít anticipated. The hoistís legs would not fit under the work table, and that meant that the engine would not go over the table. We moved the hoist around to a corner and that let the legs straddle the table and get the engine a bit closer. After rotating the engine we got one support on the table, Ryan supported the other side as I let off the hoist and then we slid the engine on the table.

The first thing I found was that Iíd lost the oil pressure restrictor. But I seem to have most everything else on hand. The new shorter dipstick tube arrived and I shortened the dipstick to suit. RV-3s and RV-4s have a tighter cowl than the other models and need the shorter dipstick tube.

One thing thatís very apparent with the motor on hand is that this is a really small airplane with a big engine. Up close, itís an impressive comparison.

Waiting for parts, I did a few things in the cockpit area - now the EMS network cable is guided by Adel clamps, and the rudder springs are finally installed. The rudder springs arenít part of the plans but some builders add them. I finally figured out how to terminate their forward end without adding any new parts: I drilled holes in the center ribs for the ends. Simple, no parts and removes weight (every so slightly).


David Paule 02-12-2022 03:01 PM

The baffle kit is sort of a fill-in right now. Itís in progress, and Iím accumulating a number of drilled, deburred and ready for assembly parts. I need to get the finish on them before that, though.

One of the things thatís much easier to do with the fuselage flopped over on its side is finishing off the mixer fasteners. I installed the grip on the control stick and bolted it to the mixer, and the mixer to the fuselage and elevator pushrod. All move with no perceptible friction and no perceptible free play. I used castellated elastic clock nuts and cotter pins on all joints.

The stick grip, thatís the yellow tennis ball, is held on with three universal-head blind rivets. They are located so itís the heads which act as stops for the grip. The grip is not riveted, screwed, bolted or bonded to the stick. It is secure, and I used a different tennis ball and piece of tube to the concept.

The dark cone in the photo just below the right hand EFIS knob is the work light I had in there. Itís not a flight part.

Next, it was time to attach the engine mount and dummy firewall to the engine. I only used two sets of the isolators for simplicity. The dummy firewall is .093 acrylic. I left the protective overlay on.

With the dummy firewall in the correct position with respect to the engine, it was obvious how little room there actually is between them. And the governor will present an interesting difficulty: the lever is aft of the plane of the firewall inside the recess (denoted by the hole in the dummy firewall).

Anyone have any ideas?

Another thing that I noticed was comparatively small potatoes - the governor bracket doesnít fit this governor. Sort of doesnít matter, though, since the firewall is in the way anyhow.

Now I can determine where I want to install the various firewall-mounted devices and where Iíll need pass-throughs.


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