All Things Electrical

I've been trying to concentrate on all of the electrical items from the firewall aft. This is cool, since I am actually bolting parts on the airframe, and the piles of parts in boxes are getting smaller.

With the exception of the wiring, I have the instrument panel largely complete. The Biggies are; handheld GPS dock for my old Garmin GPSMap196, Dynon D180, ICOM A210 Com., Transponder, and RWS ECU programming panel. You will also notice about 20 pounds of switches, used to control the ignition/injection/fuel pumps. As always, click on the photo for more detail.
On the backside of the panel, you can see two fuse blocks, a couple of diode sets and a couple of switching relays.

Throughout the airframe, I've also installed the engine and battery busses and contactors, the voltage regulator and filter capacitor and the big ammeter shunt device.

Soon, I'll get some preliminary wiring done on the panel, then get it permanently installed.

The biggest challenge, right now, is sizing the batteries. My load analysis shows that I'll need about 13 amps to keep this thing in the air. To make my system redundant, I'll need a backup battery capable of delivering 13 amps for a half hour. Yeauch!

I figured out how and where they should go, I just hate adding all that weight.

Sandy said I should just eat less and get some exercise and not worry about the battery.

Now - Where was I?

Time to get back to the fun stuff. While I was waiting for the paint to dry I did get some other work in on the aft side of the firewall. Specifically, I'm working on the instrument panel, location of the batteries, and getting the fuel system in.

Because I'm using fuel injection, I will need a fuel pump to boost the fuel to about 45 psi. It is a closed loop system, meaning, the fuel is in constant circulation as it's filtered, boosted and regulated. The pump and filter package is mounted to the fuselage wall, just aft of the pilot.

I chose Walbro pumps and I have a second as a backup. Fuel leaves the header tank via the black fuel line and goes to an aft mounted 70 micron gascolator. Then through the fuel pump, through a 10 micron filter, then through the aluminium tubing to the firewall. After making the circuit around the engine, it returns back through the firewall and is delivered to the fuel pressure regulator. After the regulator, the excess fuel is dumped back into the header tank.

One of the biggest challenges was bending the aluminum tubing, especially the 1/2" stuff. It was tough even finding the right bender. Fortunately, I was again able to tap into SIU AvTech and got hold of Professor Billy Cheek. Billy used to bend tin for the Air Force and pulled me out of the deep hole I'd gotten myself into.

The photos are showing the work in progress. Click on 'em to see 'em bigger. Please excuse the dust.










Today I actually applied power to the fuel pumps and pressurized the system. For testing purposes I took it to 80 psi, but I think I will normally run it at 45 psi. The test was a great morale boost!

Painted at last, Painted at last, Thank God it's painted at Last!

I finally got all the parts back from the paint shop.



How long has it been? I think Rob came down just before the Fourth of July and that was the start. You can see it here: http://samhoskins.blogspot.com/2008/07/cascades-of-dust.html

I've already put the elevators and ailerons back on, and I'm fitting the rudder into place. I hope to get the stripes applied soon.

The paint really looks nice and the color is consistant. I guess I'm glad I stuck with it.

Free CAD drafting program

Not that this has much to do with anything, but I wanted to let you know that there is a nifty free Computer Aided Drafting program out there I have come to use and like. It's called SolidEdge2D. It has been great for me and it's free.

Why free? Their idea is to get you hooked on their 2D program, then hopefully, you will upgrade to 3D.

I use it mostly for my electrical drawings
Following Bob Nuckolls, AeroElectric Connection, I have a large page for the main power distribution, than an individual page for each component. BTW, if you don't have a copy, get one. I consider it a must-have.

A long time ago I used AutoCad. The company I used to work for used CoCreate's ME10, which was completely different and I grew accustomed to it. After I retired, I would have preferred to stay with ME10 but it was avilable for corporate use only.

I tried some versions of AutoCad but didn't really get along with them, then I came across SolidEdge2D.

They just released a new version, so I'm getting used to it now.

Paint not yet resolved.

I'm still waiting to get the rest of the parts back from the paint shop. I really need the elevators since I will be routing things around the bellcranks.

Jon Finley suggested I choose some contrasting colors.

Now what?

Quick update here. It's definitely a good news/bad news situation.



After sanding off about $700 worth of new paint, I sent my plane to a local body shop. The interesting thing was getting a plane with a 17 foot gear width onto a 16 foot trailer. It went well and we didn't have too far to go.

They mixed a single gallon of paint and used the base coat/clear coat method - standard for automotive paint shops. We brought it home and everything seemed great - until...

Until I put the cowling on. Lo and behold, the cowling was darker than the rest of the fuselage! A closer look revealed that the flight controls, spinner, wheel cover pants were also off color.

I brought Sandy out to the airport to look at it. I thought maybe she might suggest that I live with it, but she was disappointed, too.

I had the guys come out and look at it but they couldn't figure out what happened, since it was all painted from a single gallon. They called the DuPont specialist to take a look and even he couldn't figure it out.

So, how to make it right? The DuPont guy brought a nifty scanner which he placed on the fuselage, just aft of the firewall. This device calibrates the color of the existing paint. They took it back to the body shop and plugged it into the paint mixing computer. Just like that, the computer mixes the paint to match the scan.

Today I dropped off the flight controls and some other odds & ends, to be repainted. If they look right, we'll do the cowling. The good news is that the tail cone and canopy match. I know it will be fine when we're done.

On another note, I'm starting to plumb the high pressure fuel system for the electronic fuel injection.

Progress is happening

Even though I haven't posted lately, progress is in the works. I sanded a lot of the paint off and made arrangements to have a local body shop shoot it. So far, they have shot the upper and lower cowl, the flight controls, canopy and tailcone. Today, we are supposed to trailer the fuselage over and paint it over the weekend.

No photos, with this post, instead, take a look at the photos, at Sandy's blog www.sanleeott.blogspot.com , from last week's mini-vacation in Arizona. I gave a Mistake-Proofing presentation at the National Association for Healthcare Quality on Monday, so we fooled around in Arizona for the rest of the week.

A Paint Job Gone Bad - Rats!!!

After the paint job was done, and much to my total dismay, I discovered there were significant problems with the color match on different parts of the plane. The forward fuselage/wing/canard is one shade and the tail cone, control surfaces, cowling and canopy are another.

Blame is easily dispensed, but in truth, it is shared.

Maybe I should just make a list of the issues, rather than elaborating on each one.

1. The paint booth did not have a clean regulated air supply. This meant that the pressure delivered to the air gun ranged from 70 - 110 psi. Rob could adjust the pressure at his gun, but that was a band-aid.
   
2. We did not have the proper range of tips for his expensive HVLP spray gun. Having the correct tip size is critical to accomodate the viscosity of the paint. My brother forgot to bring the other tips and was forced to use his "retired" HVHP gun, which resulted in wasting a lot of paint.
3. We used two different gallons of custom mixed paint, purchased with a one month interval. The paint shop did not properly mix the second gallon, so it didn't exactly match the first. It should have been a lot closer. However, it would have been better to purchase the two gallons at the same time, then mix them together before shooting. Bouncing up to steps #1&2 above, if we had the right gun and a regulated air supply we would have used a lot less paint and the second gallon may not have been an issue. Everything is connected.
   
4. Due to having the wrong gun, we ran out of the second gallon and were unable to paint the canopy. We purchased a single quart and it turned out that it was mixed way off and was very light. The paint shop remixed another quart, but it is not enough compensation for the extra work involved.
   
5. We shot the fuselage at the end of a long day. It would have been much better to wait until the next day when we were fresher and thinking straighter.
6. The cup used to proportion the paint, hardener, and reducer was confusing to use and not really suited to the paint we used.

Of course, my first thought was to see if I could just live with it. I brought Sandy out to look at the plane and get her opinion. She didn't like it either and said something to the effect that "you'll never be happy with this".

I brought out a father/son team from a local body shop and asked them how to make it right. Chris said the words I really didn't want to hear; "If it was mine, I'd just re-shoot the whole thing. You're not going to be able to blend this properly".

So now, almost a month after the first shoot, I have a lot of the paint sanded off and I will be hauling it off to the body shop this afternoon.

The "lessons learned" post will come later. Have a nice day.

Q-2 canopy for sale

I have a new clear canopy for sale, on Ebay.
Here is the URL http://tinyurl.com/62j6gd



All proceeds will be donated to the Plastic Explosive "Sander's Elbow" fund.

"There is No Such Thing as a Simple and Cheap Paint Job"

That quote was from the counter man at my local paint supply shop, as I returned to buy yet another $100 quart of paint to fix yet another of my screw-ups.

The week of prepping, primer and painting was an exhausting marathon. As I write this, Rob is on the train on his way back to house and family.

Some of the good things were: getting to spend time with my brother, getting the benefit of his years of experience, getting to use the SIU Aviation Technology paint booth, getting help from some of the SIU students, getting rid of all of all that old cracked paint and filler, having Sandy provide critically needed logistics support, and finally, getting paint on the bird.

Some of the not-so-good things were; having the wrong tip on his new HVLP gun for the DuPont Centari and getting runs on the vertical stab, sticker shock at the paint store, and me mis-mixing the paint used on the main fuselage resulting in excessive orange peel which will require extra wet sanding after everything cures.

I really didn't want to repaint the thing, but now that I have, I'm sure I will be happy with it. But, oh man! What a job!

Getting the Primer On It

Moving day! I was able to get my main man, Robbie Hoskins down to direct the painting operation for this little beast. Again, I am grateful to SIU's Aviation Technology department for allowing me to use the facilities. In this case, it is there brand new paint booth.


After a week of sanding the epoxy wipe, I was ready for Rob and his magic paint gun. First, we had to tow it over to the AvTech hangar. Rob couldn't really believe it when I told him how were going to do this.


A little last minute sanding was in order.


We warmed up by prepping and shooting primer on the tail cone and the upper and lower cowl.

Now we had to figure out how to handle the fuselage. With the assistance of several AvTech students we lifted the plane and placed it on a large wooden dolly they had laying around. A few screws fixed it into place.

It was really great having Rob help and he really knows what he is doing. We finished the second day with two coats of primer on the cowling and tali cone, and one on the fuselage!

Doing the Epoxy Wipe

This is a great technique. I first became aware of it when reading an article about Cory Bird and his most perfect Symmetry.

In "the old days" we would apply filler, then use progressive grits of sand paper until we had a very smooth finish. Then we would apply primer, or maybe more micro, to fill all the pinholes. Then we would sand it off, only to find that the pinholes where still there. Over and over and over.

Using the epoxy wipe method I sanded with 36 Grit, then a quick once-over with 80 grit. The epoxy wipe fills pinholes, pot holes, scratches, gouges and all sorts of other sins. It also does a great job of hardening the soon-to-be-painted surface.

Today, we filled the forward fuselage, the tail cone, upper cowling, lower cowl and the upper surface of the canopy. I used West 105/206 epoxy and applied four skim coats.

The idea is to apply it, then squeegee off as much epoxy as you possibly can. When it gets tacky, repeat. With all the components I was working on, I just kept rotating through. It took us about 4 1/2 hours. It really helped having Sandy mix while I was working. It was warm in the hangar - 88 F degrees.

I also wanted to keep track of the weight I was adding. We kept track of every cup mixed and I figure we added 2.2 lbs.


Now, I'll sand it all with 180 Grit and it's ready for paint.

Sanding

Over the years, we have learned better sanding techniques than were called out in the original plans. I'd thought I'd cover some of the main sanding tools that I now use. (As always, click on the photo the the full size image).

Again, the main idea is to lay your filler material on THICK, then sand down the high spots until you just reach the fiberglass. There are two excellent on-line descriptions that describe best practices.

Chapter 25: The Contouring Process

and

Finishing a Composite Airplane

1. Sand Paper The first strong recommendation is to buy only automotive body shop quality paper. I think that the 3M paper is the best and longest lasting and is my preference, by far. I get my paper at a local automotive paint shop supply store.

Almost all of the work will be done with 36 grit paper and I keep a good supply on hand. I really like the stuff that comes with the adhesive backing. It's 2" wide by 16" long.

2. Small Sanding Blocks Try and avoid doing any sanding, at all, with just your fingers - always use a sanding block. If you use solely your hands, the paper will follow the contour of the thing you are trying to sand down and you will not get a smooth surface.

I make extensive use of the rubber sanding blocks - there are both 6" and 8" available. I stick the paper to both the curved and straight sides.

For fillets and the like, I simple stick some 36G on a piece of cardboard tube.

I have also used this single stick board for many years.

3. Long block I used some shelf board I had laying around and cut it to 32" and mounted a section of aluminum angle for a better grip. This length allows me to use two 16" sticky back strips. With fresh paper, this is a great tool and really cuts into the micro.

I strictly use 36 grit on the whole plane until I get the contours that I want. When I have that desired shape I switch over to 80 grit. All the 80 grit does is to knock off the highest cuts left by the 36G.

All sanding should be done at 45 degree angles.

Don't worry about deep scratches, pin holes, deep holes or black holes. The next step will take care of it all,

Next, comes the epoxy wipe!

Good to Be Home

I did Oshkosh for the whole week. Saw lots of folks and did lots of stuff.

Paul Fisher and his boy, Roy came out and helped with pyro. Yes - those are real sticks of dynamite!

When we shot the wall of fire, Doc and I peered over our standard issue cardboard blast protection. Roy ducked a little.

The minor irritation of the week came from some Vari-Eze driver who showed up with the Plastic Explosive label on his plane. He must not know who he's messing with.

Now, back to sanding.

Off to Oshkosh

I have flown my little Quickie into Oshkosh 19 times and this year was to be the 20th. Oh well.

Sandy will be missing the big event. Since I wasn't planning on going, she made other plans.

I was pretty much resigned to skipping it all together this year, when Ken Robinson came along and asked me if I would like to fly his 1955 C-182 up to Wisconsin. Ken has been the benefactor of the SIU aerobatic team. Just to sweeten the pot, he is throwing in an armband.

So, how could I say no? I'll be tenting under the wing of the C-182 for a couple nights, then I'll transition to a hotel room with Rich Gibson and the Pyro crew.

One of the best things about having Race 22 at Oshkosh is just hanging around my plane and see who shows up. I get to see old friends, remote Quickie builders, former students and others - I'll miss that this year.

But, like the Chicago Cubs - Wait till next year!

The Sands of Southern Illinois

The coating of gray primer really helps you to see what needs to be sanded next.

Small Update

Just another photo or two of the filler.

I went around with my sanding grinder and knocked off most of the high spots and clumps. (Making lots of dust!). I went to Wal-Mart and got a couple cans of cheap gray primer and sprayed the fuselage. I found this is a big help to find the low spots while sanding. I would have preferred a darker primer, but I didn't want to chase around for it.

I think I'm beginning to develop "sander's elbow".