Carlson Skunk Works

March 6th, 2019

amf 14h maranda sn:1026 Making Sawdust February 20, 2019

Posted by Roger in news

Well! It has been a long time since I had a chance to post my progress, so this could get to be a bit on the long side. Progress has been made, but it has been smaller things that don’t show much. The instrument panel is basically finished. The firewall is complete and in place. The rudder pedals are in place and working. And the steps have been finished and are in place. The next thing is to run the break lines and test them. The elevator trim mechanism is in progress and nearly done.

So, now for some of the pictures:

The first thing I had to do was drill the holes through the firewall so they would all line up correctly.

Then I positioned the FiberFrax and clamped it between the front bulkhead and the firewall.


Then I started putting things back in place FOR THE LAST TIME!!!!

The master solenoid, battery, gascolator, and voltage regulator are in place.

The next thing to work on is the rudder pedals and breaks.

Here is how I set the rudder clearances.

This mechanism allows me to adjust the rudder so it won’t even think about bumping into the elevator.

The last thing I have been working on are the steps. I ran into a number of problems with this, but have them all worked out now.

The rubber step grips are from Harbor Freight and sell for less than $3.00 each.

And there is where things stand right now. Should the weather warm up a bit I will be working on running the break lines.


October 9th, 2017

AMF 14H MARANDA SN:1026 Making Sawdust October 9th, 2017

Posted by Roger in news

In the past month or two things have progressed to the point where bolts can be installed permanently. YEAH!!!

That means that the engine has been removed, the firewall has been formed, and the firewall is now in place. That also means that there are only a few pictures to deal with.

The engine and engine mount were removed along with everything else on the front of the fuselage.

I obtained a piece of sheet steel for the firewall and drilled a couple of holes so that it could be hung on the front of the fuselage on the top bolts for mounting the engine mount. To give a bit of backing for drilling holes and bending the edges of the firewall, I cut a piece of 1/2 inch plywood and hung it on the top bolts as well.

I bent the firewall metal around the plywood. The curve on the upper edge caused the metal to wrinkle.

Ben came to the rescue and welded up a set of fluting pliers from an old vice grips and some 1/4″ rod. This allowed me to insert some “controlled” wrinkles into the firewall top edge.

When that was done and the firewall looked pretty good, I took it off of the plane and spray pained the back of it with high temp primer. This primer is supposed to be good to 2000 degrees. While the paint dried I sprayed the front of the front bulkhead with Elmer’s spray adhesive, then applied FiberFrax to the wood. I finished up by putting the firewall back in place.

While I was working on the firewall, Emmett and his friend Gannon went to work and applied sealer to all the wood parts that I had been working on for the past year. These included the mount for the fuel tank, the seat parts and the baggage compartment parts.

Now I can focus on the final mounting of parts in preparation for covering the fuselage.

August 31st, 2017

AMF 14H MARANDA SN:1026 Making Sawdust August 31st, 2017

Posted by Roger in news

My last post was in March!
Things have been happening since then. Progress has been made on Sawdust and we attended AirVenture. Of course, the main thing here is to document the progress on Sawdust.

The primary focus has been on the wiring, instrument panel, plumbing and firewall forward. At this point I have only a couple of wires to finish. These are the wires that will provide ground continuity from the engine to the engine mount, on to the firewall and gas tank, then finishing up at the bus bar.

These are my bus bars. The one on the pilot’s side of the plane is the positive and the one on the passenger side is the negative.

The aluminum angle will support the battery and a bracket will hold it to the firewall.

The other side of the firewall bulkhead has the voltage regulator. This also has room for the gascolator and the cabin heat duct.

The instrument panel is about ready to be pulled and finished. I am going to make an aluminum sheet section for the breakers to fasten to. This will be something like the one on the other side where the master switches are located.

I found an inexpensive throttle cable. For about $45 I got a 30 foot long remote throttle cable generally used for trucks and other equipment. However it works pretty well and was much less expensive than what was available in Aircraft Spruce. This cable can be locked in place when the desired setting is reached and has a vernier mechanism that allows fine adjustment by turning the knob. The red button overrides the vernier control for rapid changes.

The fuel line plumbing is done. Well, it is figured out and the rough installation is complete.

I have the tail feathers fitted and am ready to install the rudder pedals and cables.

My big purchase at AirVenture was the propeller. I knew that I had some bolts at home that would be too long, but the right diameter, so I waited until I got home to try to figure out how long the prop bolts would need to be. I put a bolt through the holes and marked the length. Then I wrote down the length and proceeded to order the bolts. When they arrived I found out that I had measured correctly, but wrote the length an inch too long. So, I ordered a second time. When the bolts came they were 1/4″ too long!!! The “correct” bolts are supposed to arrive at home in the mail today. Wish me luck!

The other thing that I did was to install the cable for the remote switch for the ELT. I still have to solder the ends of the cable to the switch and get the power connected properly.

Just keeping on keeping on.

March 23rd, 2017

AMF 14H MARANDA SN:1026 Making Sawdust March 23rd, 2017

Posted by Roger in news

Weather, a wife with a broken arm, and other issues have kept progress to a minimum since my last post. However, some progress has been made. My focus has been on painting the inspection covers and the vertical stabilizer, which can be done in the basement in short bursts of activity; and on the layout of the instrument panel.

I now have acquired all of the instruments for the panel, so I know the sizes of the holes that need to be made. I also have a cardboard template to work with. The most recent instrument acquisitions are the oil pressure and oil temperature gauges. These were purchased from Amazon during one of their recent incentives. The two gauges are a matched set, are round, and are electrical, so I don’t have to worry about capillary tubes breaking and such.


The oil temperature sensor was not a problem at all to fit to the engine. However, the oil pressure sender unit would not fit into the area where the block is tapped for this purpose.



What to do? I remember seeing an article someplace showing how someone else with a similar problem solved it by using a hose to allow mounting the sending unit a short distance from the engine. So I spent some of my lunch hour the other day to visit the aviation department of my local Orscheln’s Farm & Home store and found just what I was looking for; a replacement hand grease gun hose!


They had one without a protective wire around the base and they had this one which I thought was just right. I like the protective wire/spring guide because I think it will help to keep the hose away from hot engine areas, and it looks cool. The hose has a 1/8 NPT thread on each end which is exactly what is needed to match the hole in the engine. On the other end I got a coupling to go between the hose and the sending unit.



I actually got a couple of the couplings and a close to give me a few options for mounting the sending unit.


What I am thinking is that I will make a piece of steel sheet to bend around the engine mount and have holes for the close to pull things together. I may eliminate the close and one coupling if things look like they will fit OK without them. That part still needs to be figured out.



Slowly, but surely!

February 25th, 2017

AMF 14H MARANDA SN:1026 Making Sawdust February 25th, 2017

Posted by Roger in news

It has been a long time since my last post. Things have been busy, however, with a new job with a 60 mile commute, a wife that insisted on breaking her arm significantly, and a bunch of cold weather. However, I have made some progress and things are starting to warm up outside.

Just before it got cold I got P-leads and an ignition switch. I found a reasonable place on the panel for the switch, installed it and then ran the P-leads.


Of course, I forgot to get a picture of it from inside the cabin, but you can see how it is installed. I added another piece of tube to allow the P-leads to go through the firewall. Each of the tubes that penetrate the firewall will have a firesleeve on it. I still have to order that.


We have a new Maranda 14-H builder. I would like to welcome William Powel to our group! William is a helicopter pilot that has decided that building a wooden airplane is something he would like to do.

William is at the point where he is trying to figure out the details of fitting the two fuselage sides together. He called me and asked a few questions and I thought it would be a good idea to go out to the airport and take some pictures. He said he had looked through my blog, but didn’t see what he was looking for. Therefore, here are some pictures of how the front cross member fits into place and a few others showing other things in that area.












Here are a few pictures of the top of the same area of the fuselage:











In the mean time I am painting the inspection covers and vertical stabilizer down in the basement. I have also ordered an oil pressure gauge and an oil temperature gauge and an inclinometer. I ordered them from Amazon and they are supposed to be here on Tuesday. That means I am going to be getting serious about laying out my instrument panel.

October 25th, 2016

AMF 14H MARANDA SN:1026 Making Sawdust October 25th, 2016

Posted by Roger in news

I keep putzing along and making progress. I am amazed that there are getting to be fewer and fewer “projects” to complete each day! I am starting to feel like one of these days the plane will be done.

So one of the unfinished items from last post was the seat and baggage area. Other than upholstery the seat and baggage area are now complete.



The back of the baggage area is a wooden frame with a 1mm plywood front. I added a couple of small wood blocks behind it on the window framing to keep it from falling backward into the fuselage. The whole assembly is easily removed to allow access to the elevator bellcrank and aileron cable ends.


Another item was the air intake which got crunched when the plane took a nose dive. This has been cleaned up, straightened and reinstalled.



I still need to safety wire two bolts and castle nuts toward the front of the assembly.

Before I can glue the plywood over the nose and dash I want to get the wiring and plumbing installed. The first order of business was to figure out how to activate the starter motor. The C-85 has a “pull starter” that requires a cable or rod to be run from an arm on the starter to the cockpit. Here is how I finally decided to do this:


I used a 3/16″ rod for my actuator and bent it at a right angle, then threaded the short end.


I eyeballed the anticipated run for the rod and drilled a hole in the firewall. The hole is large enough for a steel tube to extend through the firewall and act as a guide for the rod. Another hole was drilled in the instrument panel where I wanted the end of the rod to be accessible for starting the engine.



Of course, the rod had to go over the fuel tank and miss the filler neck, but everything just seemed to work out.

The next thing was how to actually pull the rod from inside the cabin. I had some left over pieces of Delrin, so I drilled a 1″ hole for my finger to go through and a hole for the rod to go through. I used the Dremel tool to shape the edges and make a notch to accommodate a nut and washer.


Next on the list was to decide how to control the throttle. Yesterday I spotted a throttle and mixture control quadrant on Barnstormers, so I contacted the seller and it should be shipped later today. I have quite a bit of Belden cable left from the trim control, so I started working on running some of that.




This looks like it will work out quite nicely! The next issue is how to mount the throttle quadrant assembly? So I added a piece of wood reinforcement between the fuel tank restraint and the instrument panel. I won’t be able to complete the installation until I have the throttle quadrant, but this is a good start.



As long as I have good access to things, I decided to complete the fuel gauge sender installation. I had the base of the sender in place on the fuel tank just to keep dirt out, but I needed to install the float. Following the instructions that came with the unit was pretty easy. The hard part was getting the assembled unit into the fuel tank. I ended up loosening the sender rheostat so it could slide down the support and fit through the hole. Then I could slide it back into place and tighten the screws to secure it. The other surprise was that the float now sits toward the side of the tank rather than toward the center of it. If you use one of these, be sure to take into account which way the float will extend from the support before you weld the mounting ring to your tank. The holes in the mounting ring do not allow for multiple positions of the sender!

October 20th, 2016

AMF 14H MARANDA SN:1026 Making Sawdust October 20th, 2016

Posted by Roger in news

So the wings are done, that means that I need to finish the fuselage. There are quite a few details that need to be dealt with before I can start covering and painting.

One requirement is that the plane be fitted with an ELT. I purchased a used Pointer ELT at the AirVenture Fly Mart a couple of years ago. However, I thought I would just buy a new Ameri-King AK451 from Aircraft Spruce instead. I ordered the new unit, but was informed that these are no longer available from AS. At that point I decided to use the ELT that I already had. Parts are available for it from AS, so I can still get a new battery and it is still legal.

My ELT needed an antenna, mounting tray, and new battery at a minimum. I also wanted a remote switch. When I added up the cost of these on AS it became obvious that a bit of time looking for used parts might save a considerable amount of money. I was able to get the antenna, mounting tray and antenna cable on Barnstormers. I still will need a remote switch and a new battery. The switch kit is available at a reasonable price from AS and will be part of my next order. I will order a new battery just before the final inspection. That will get me the longest time before it needs to be replaced again.




I bent up a mount for the antenna and bolted it in place. Then I attached the antenna cable and zip tied it in place.

Another thing that needed to be done was to improve the tail spring mount. There is a large bolt holding the front of the leaf spring in place and I had a couple of threaded rods farther back to hold the leafs straight. The threaded rods needed to be replaced. I decided to make a “U” type of bolt with nearly square corners at the “U” end. So I got a piece of 3/16″ steel rod, bent it to shape, cut it to length, and threaded the ends of the legs.



That worked pretty well and I was having some issues with finding bolts to hold the horizontal stabilizer to the fuselage, so I got a piece of 1/4″ steel rod and repeated the process.



I will probably need to cut the threaded ends off a bit, but that can wait for a while.

The elevator cables rubbed against each other near the middle of their runs. I tried to come up with some type of small separator, but couldn’t get things to work quite right. What I finally came up with was a chunk of PVC pipe that would sit between the cables and have guide notches cut in it.



The plans call for the fuel tank to be mounted in the nose of the plane aft of the firewall. I followed the plans to build the fuel tank, but found that the specified mounting method just didn’t work for me. So I came up with this mount:


That holds the tank up and across the top I added a wooden restraint to hold it upright and generally in place.



The curve of the top of the fuel tank is not the same as the curve of the top of the firewall. That put the fuel filler neck and cap inside the nose of the plane. I took the filler neck to a friend who cut it and added a piece of tubing to extend it to reach above the nose deck.





That worked out quite nicely. HOWEVER … while working to get the fuel tank in place I managed to push on the nose of the plane just a bit too much and it v.e.r.y..s.l.o.w.l.y tipped over onto it’s nose! Fortunately the engine was not running and the “tip over” was very slow, so damage was minimal.



Only the air intake box was bent and I think I can straighten it. It will need to be removed from the carburetor, though.

So, with that experience behind me, I tied the tail of the plane to the workbench.


The next project was to design and build the seat and luggage area. I decided to have a bench seat with a back rest that would tip forward for access to the baggage area.



Under the seat will be storage area for an emergency kit, some tools, and misc items that do not need to be accessed during flight.



The luggage area is behind the seat and has enough room for a couple of suitcases, a small tent, and a couple of sleeping bags. I still have to build the retaining wall/device so my luggage doesn’t end up in the tail.


The seat and luggage area are easily removed, should that become necessary, by taking out a couple of AN-3 bolts.

In my “spare” time I have been helping my son insulate and sheetrock his garage. He suggested that we move the fuselage into the long bay in his garage this winter, so we can finish it up and have everything ready to fly in the spring.

Now, on to the rudder pedals, brakes, and instruments!

September 19th, 2016

AMF 14H MARANDA SN:1026 Making Sawdust September 19th, 2016

Posted by Roger in AMF 14H Maranda SN1026

So the wings are done, as you saw in the last post. However, I have been trying to come up with a way to test the wingtip lights and strobes. I have really been scratching my head on this and have come up with several “elegant” ideas, but they were just too complicated. Then my son suggested just using my battery charger. Duhhh! Now why didn’t I think of that?

So here is the result:




And here’s the video:

August 26th, 2016

AMF 14H MARANDA SN:1026 Making Sawdust August 19th, 2016

Posted by Roger in news

So, rib stitching took less time than expected. Applying the finishing tapes and perimeter tapes took quite a bit longer than expected. However, the wings finally reached the point of being ready to paint. Ben brought two small folding tables out to the hanger and we were able to set one wing on them and the other on the workbench which allowed me to paint both wings at the same time.

Six coats of primer were applied to both sides of the wings. That used up the remainder of the first gallon of primer and most of the second. The first two coats of primer were applied with a foam brush with the second coat being applied perpendicular to the first coat. All subsequent coats of primer and paint were applied with a small dense foam roller.


A wing with all the primer applied.


The same wing after the finished color has been applied. Note that the aileron has been attached as well.

The screws that I had planned to use to attach the ailerons turned out to be too long. So I ordered shorter screws and am currently waiting for them to arrive. However, I was able to mount the wing tip lights which required that I open an access hole in each wing.



The access hole was required to allow me to reach inside the wing and direct the wire for the lights out through the hole in the wing tip.

The cables that I purchased for the lights came with the mating connector body and pins that needed to be crimped onto the wires on the wing tip light and strobe assembly. There are four wires on the light assemblies. A red and orange wire are provided for the +14v for the strobe and the light. A black wire is for the ground and a yellow wire is for synchronizing the two strobes if that is required or desired. I like the idea of synchronized strobes. Since the cable only has three wires inside its shield, I crimped the red and orange wires together. This will provide voltage to both the navigation lights and the strobes at the same time; i.e. if the wing tip lights are turned on the strobes will be turned on as well.

When the pins were on the light assemblies I plugged them in and mounted each light on the end of the appropriate wing.






July 26th, 2016

AMF 14H MARANDA SN:1026 Making Sawdust July 26th, 2016

Posted by Roger in news

Covering the wings took much longer than I was expecting. It didn’t seem like it at the time, but there are a lot of details to tend to and each task takes time. This is the third post dealing with covering the wings. But now they are covered and I am on to painting them.

Rib stitching seems to be something that people are very hesitant about. So was I to begin with. However, after doing a couple of ribs things started developing a rhythm and went pretty fast. I thin the first short rib took over an hour, but by the time I got to the final long rib in the slipstream, that long rib only took an hour and short ribs were taking about half an hour. I used my lunch time to go to the airport and do a rib or two each day during the week and it only took two or three weeks to finish all the ribs.

The rib stitching technique that I used is available on YouTube:

Once the rib stitching was complete I marked the locations of the surface tapes and applied them.





I used the Stewart System process where glue is applied to the fabric over the ribs, then the tape is placed onto the wet (well, not yet fully dry) glue, and glue is applied over the top of the tapes and wiped off to smooth it down and get rid of any excess glue.

Reinforcement “doilies” were made for anyplace where something has to go through the fabric. This included the strut fittings and pitot/static tubes. I made 8″ diameter doilies for these areas, but I was not fully pleased with the result. I must have cut things a bit too loose; i.e. I cut holes a bit too large. I went back to the places that I wasn’t satisfied with and added in some short pieces of tape to bridge the openings, then cut 4″ doilies to go over the tapes. I liked the final result and I don’t think the extra tapes will really show once the wing is painted.

I also put an 8″ doily over each of the mounting blocks for the wing tip lights.



Ben helped me move one of the wings to the workbench so I could apply the leading edge and perimeter tapes.

After cleaning up my work area and putting the covering materials away, I washed the top surface of the first wing to get any debris off of it that was picked up during covering and tape application. I just used a paper towel that I dampened to wipe the dust and dirt off of the wing.

Then I went home and got the painting supplies to start applying the primer.


Zinsser Bulls Eye latex interior & exterior primer in gray. This is diluted with water to approximately 75% primer and 25% water or maybe a bit more dilute. Then I used a foam brush to apply the primer to the wing.



The first coat of primer is being applied parallel to the ribs. The second coat will be applied perpendicular to the first coat.

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