3DHS 84" Bigfoot Build Log

[SnowDog]

Hey guys, I'm starting a build log for my Bigfoot. I'm going to follow the manual as closely as possible but I'm also going to highlight changes/updates based on this build and other builds that have already been completed.


This plane will be getting an OS GT33 for power.


So let's start with some basic pictures of the unpacked box:



As usual the double box shipping box saved my model from the UPS "Hulk" drivers ("Hulk smash"!)
Not that bad really, one corner of the box was slightly dented; no damage inside!

 

[SnowDog]

Removing the covering and installing the tail surfaces...nothing unusual here:

 

[Plowboy]

Go Dog Go!!

 

[gyro]

Any recent progress?

 

[SnowDog]

I do have some recent progress!...just need to find time to update the build log and post some pics.
tail surfaces are finished without any trouble.
Working on aileron and flap servos tonight and mounting the engine tomorrow night.

 

[ANDYjuice22]

Good luck on the build! It is different than most 3D planes and more tricky but its all worth it afterwards lol

 

[SnowDog]

Did some digging around regarding engine standoffs...since I'm installing the OS GT33, I needed to know the length of the standoff required. Per Noll,

1.5 inch standoffs for the OS 33 GT.

Firewall to front of cowl measures 6 1/8 inches.

The cowl is mounted with four wood screws, similar to our other 30cc airframes so some adjustment can be made.

 

[SnowDog]

more progress on Bigfoot...still working on the basics that are familiar to any 3DHS airframe build.






No surprises here. Even though the manual suggests to mount the gear and fairings as the first step, I decided to defer installation of the gear and fairings until later in the build. I've heard that the fairings get banged around during the build and I wanted to save them the abuse of my build table.

The tail surfaces installed straight and true; no sanding was necessary.

The next step will be installing the tail servos, running the wires, and installing the control linkages.

 

[SnowDog]

Still digging out from the backlog...here are some more pics...this time the servos and linkage instalation on the tail surfaces:


thought I would try out the tape around the control horn technique.
It does work well...but don't let the epoxy set fully before removing it.


this was an oddity...one set of control horns had a shorter base length.?


everything is taped, aligned, and glued.


finished installing the rudder linkage and servo. Servo in the tail because this is a gasser.
don't need much length on the servo arm to get full travel on the rudder.

I do prefer to use my own mounting hardware (socket cap screws with built-in washer) instead of the stock phillips head screws; the head on those screws is just too soft and once screwed in, I always seem to strip them when I need to uninstall them. Socket head washer screws from trimcraftaviationrc.com work really well and are a really good value.

elevator servo linkage worked just fine.


I did have to cut off a small amount on the threaded rod for both the rudder and the elevator...they were both too long by at least 1/4 inch.


next step on the tail: support wires and tail wheel...stay tuned.

 

[SnowDog]

Well I'm all caught up with pictures, except that I did more work tonight, so I'm posting this pics now so I can stay on track! Tonight I decided I was going to install the aileron and flap servos in both wings. I didn't realize at the time what an aggressive goal that was! I work slow and steady, always try to check things twice or three times before I glue or cut, so this step took a while.

checking the aileron and flap deflection:


trial fit control horns and check travel. Seems to be plenty of clearance for both aileron and flap:


after reading the manual completely before starting the build (everyone does this, right?) I discovered that the manual states two different values for desired flap deflection. 70-75% is the max flap deflection based on the latter section of the manual and community knowledge.


1.5" servo arms are installed on the aileron and flap servos in order reach above the surface of the wing from the pocket into which the servos are installed:


I must say that a recent trip to Harbor Freight yielded a great tool which was very handy during this step:

as I mentioned I prefer the socket washer head screws for the servos and other similar applications. The rachet tool proved to be indispensable during this step, as was the hex extension shaft which made it very easy to install the flap servo.

one item to note: the string which is in place to allow the servo wire from the aileron servo to be routed to the wing root was threaded directly through the space where the flap servo is to be installed. It was no big deal to thread the string around the flap servo opening, but it is worth noting. This is something that should be addressed as a build issue for future production runs of the product.

Here is one aileron servo installed and cover attached:

okay a good bit of work, but one wing is done!


fast forward an hour or so....and...


both wings are done, control horns are glued in, and waiting for the epoxy to dry.