Chuck and Ryan's Build Tips

[aeroaddict]

Wow, excellent! Nice job.

[ceslaw]

Wow, excellent! Nice job.

Thanks.

Now need to finish the plane so I can get a real passenger report on the seat.

[ceslaw]

Proctologist wanted. Installation of the two AN3-7A bolts securing the front seat is a real pain in the butt. Here are some tips that made it easier.

1. Make sure the battery is disconnected. Power is always suppled to the two ignition breakers, carbon fiber is a conductor, and a slip of the wrench may fry some wires.

2. Drill a 1” diameter hole on the inner side of the seat pedestal / battery box insert with a hole saw before it is installed. A plastic plug from a hardware store will close it when done.

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3. Invest in a boroscope. Mike Busch, who has authored several books on engine care, is a strong advocate for inspecting inside the engine cylinders contending it provides more information than a compression check, so we got one. Feeding the scope up from the bottom provides an excellent view of the threaded portion of the seat bolt extending inward.

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4. The tricky part is placing the bushing and washer. A long grasper tool worked well. The other tools pictured were also handy. (It is starting to look like an operating room).

5. Finally use a 3/8” nut driver to set the nut in place with the guidance of the boroscope through the 1” access hole. The access hole is a huge help providing a means for tightening down the nut and bolt. In this boroscope picture the 3/8” socket is on the nut.

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Another option is to install the seat before the pedestal insert / battery box is in place, holding the seat in a forward tilted position. This can make adding the screws that hold the insert and adding the protective clear tape a challenge. So, pick your challenge!

This was a tricky job going back and forth between the bottom and top of the seat pedestal. But these tricks enabled me to get the job done in about an hours’ time without any help. A proctologist could probably have done it in half the time.

[Andy]

Proctologist wanted. Installation of the two AN3-7A bolts securing the front seat is a real pain in the butt. Here are some tips that made it easier.

I have struggled with seat installation and removal and decided some time ago that holes near where you put yours would be useful.

Do your holes allow access to the bolts with the seat in the full forward and tilted position? I had estimated they would need to be quite a bit further forward than shown in your photos. I think it should be possible to fit and remove the seat with no access from below if the bolts can be fitted/removed with seat full forward and tilted.

BTW - I made a special wrench long enough to reach the bolts and extend below the bottom of the fuselage. I won't need that when I cut the holes next time the seat has to come out.

Edit to add - I found the operation was a lot easier if the bolt was inserted from inside with the bushing locked to it (a paper shim will hold the bushing tight on the bolt) so only one part to fit from the inside.

[Dan L]

In another thread I showed how I changed my seat base to a slider and use pins accessed from the cabin to move or remove it. But the reason I’m commenting is that I’d be somewhat cautious about putting new holes in the base because they may allow Carbon monoxide a new path to enter. The belly pod thread shows that air flow can get weird in that area behind the cabane.

[ceslaw]

I have struggled with seat installation and removal and decided some time ago that holes near where you put yours would be useful.

Do your holes allow access to the bolts with the seat in the full forward and tilted position?

Andy:

The access hole is set back a bit from the most forward seat position to avoid interference with the the ELT switch which I located on the right side, opposite the ignition breaker panel. Indeed that ELT switch is visible in the boroscope photo previously posted.

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I had no problem tightening the nuts through the access hole with the seat in the normal position using the boroscope for guidance from the front. It might be a bit easier to move those two access holes forward and tilt the seat so they nuts can be accessed from the rear, but I am not sure it would make much difference.

Inserting the bolt from the inside, perhaps a socket bolt with a long allen wrench, would indeed make the task even easier.

[ceslaw]

But the reason I’m commenting is that I’d be somewhat cautious about putting new holes in the base because they may allow Carbon monoxide a new path to enter.

Dan:

Good point. However the plastic plugs go in tight and provide a good seal. if there was any concern a tiny bead of sealant would provide additional assurance.

[ceslaw]

Dave:

Point well taken and indeed noted in the earlier post:

"Another option is to install the seat before the pedestal insert / battery box is in place, holding the seat in a forward tilted position. This can make adding the screws that hold the insert and adding the protective clear tape a challenge. So, pick your challenge!"

[Andy]

"Another option is to install the seat before the pedestal insert / battery box is in place, holding the seat in a forward tilted position. This can make adding the screws that hold the insert and adding the protective clear tape a challenge. So, pick your challenge!"

There is a difference between building an aircraft the first time and having to take it apart to maintain it later. With holes in the right place it should be possible to remove the seat with no additional tasks except disconnecting the battery.

There are several aspects of the FX-3/EX-3 design that make initial assembly easy and subsequent maintenance much more difficult than it should be.

[PBY Catalina]

There is a difference between building an aircraft the first time and having to take it apart to maintain it later. With holes in the right place it should be possible to remove the seat with no additional tasks except disconnecting the battery.

There are several aspects of the FX-3/EX-3 design that make initial assembly easy and subsequent maintenance much more difficult than it should be.

Very good remark Andy !