Building Seamaster Day 64: Silicone

Silicone for Water proofing

June 15th was about water-proofing the cradle in the fuselage for the wing. This involved using a cocking gun to apply silicone all along the top edge of the cradle in the fuselage (where the wing sits) and making sure to place lots up under the ‘water-deflector‘.

To prep for this job I wrapped some seran around the front center of the wing and taped it in place to prevent silicone from getting onto (and drying) to the covering of the wing. Teh wing is assembled on the fuselage during the drying process to make sure that the silicone forms properly to how the wing needs to fit and a tight seal is made.

Unfortunately during this process (we didn’t test the wing installment first as hasn’t been tested since installing the ‘water-deflector’) we realized the wing didn’t fit on the fuselage anymore and had to use the dremel tool to shorten the backside of the deflector, which will have to be covered again (since wood on the back edge is now exposed) , to get everything to fit correctly.

You can now really see the aircraft coming together in the image below:

Forming Silicone To Set
Forming Silicone To Set

Below you can see what it looks like from underneath. The seran taped into place and the wing sitting in the siliconed craddle.

Forming Silicone To Set - Under Wing
Forming Silicone To Set – Under Wing

Building Seamaster Day 63: Water Deflector & Nose Weight

Deflector Covered

June 8th I sanded the front of the previously installed ‘water deflector’ to make it more aerodynamic and not have such a flat leading edge, but rather conform more closely to curve of the piece it is attached to. I then covered the ‘water deflector’ in yellow to give it a cohesive look with the top of the aircraft and protect it (as everything exposed pretty much gets covered!)

After that I measured out and cut a slot into sponges for lead weights. I then placed the lead weights into the slots and sandwhiched them between the two sponges, wrapping elastic bands around to keep them firmly in place.

I then inserted the sponges into the nose of the aircraft through the former. You can see the yellow and pink sponges set into place in the image below… sorry this one is a bit blurry:

Nose Weight Sponged
Nose Weight Sponged

The other task for the day was cutting a piece of light balsa and sanding it to finish in a graded triangular shape and gluing the balsa to the switch plate (seen clamped in the feature image). This is to keep the wire controlling the switch, goes through the fuselage for access when the wing is on, at a better angle to get the required leverage.

Building Seamaster Day 62: Water Deflector & Enclosure

Water Deflector - keeps water from getting under wing compartment

June 3rd, I made a wooden plate that slides around the back of the pylon with a lip over the craddle for the wing. This is to deflect any water that splashes up over the front from getting inside the fuselage. I measured Peter’s version on his seamaster to get an idea of location and dimensions of the slot to be cut.

Once prepped I glued and clampped the piece in place, as seen in the featured image (above).

Next, I cut sponges to fit around the fuel tank to keep it snuggly in place as well as tubing for the fuel lines. Do not want the tank shifting while in flight. I then ensured the tank with the added padding and tubing connected fit appropriately.

After the trial fit I drilled a pilot hole into the firewall for one of the previously drilled holes in the fiber-glass enclosure. I then lightly screwed it in place an continued for the other holes in the fiber-glass as Peter manuvered and held the aircraft so I could get to the various pre-drilled holes in the fiber-glass and drill the pilot holes into the firewall.

Afterwords I screwed the fiber-glass enclosure onto the firewall.

Tank Padding & Tube Fitting
Tank Padding & Tube Fitting

Building Seamaster Day 61: Tank Fit & Power Switch

Fiber-glass Casing

We were having an issue with getting the tank to fit in the fiber-glass housing along with some foam for protection to prevent it from raddling around.

On May 11th I did a trial fit of the tank, with the foam stuffed in, now that the engine is mounted, painted, etc. to make sure things were coming together as expected.

I also started prepping the switch I sanded off the piece of plastic that protrudes over the actual switch as well as drilled a hole into the switch itself due to how I need to rig it up and then cut out a rectangular piece of wood that will fit into the fuselage where I need the switch to be. I then measured where the center of the switch needed to be and cut out a hole about the dimensions of the switch back, sanding to finish the fit. I then put the switch through, back plate on the back, and screwed the two pieces together to secure the switch in place.


Building Seamaster Day 60: Sanding + Wing Tip Floats

Coming Together

May 8th I returned to sanding, in this case paint, as after painting the pylon I needed to do some sanding on the bottom portion in order for the pylon to fit back down into the slot on the fuselage. I sanded to the curve of the top of the fuselage to keep the better finish in visible areas.

You can see the plane coming together in the featured image at the top with the newly painted pylon fitted.

I also got the wing tip floats attached to the bottom of the wing. This invovled figuring out where the screws needed to go in order to match up to the previously installed balsa blocks in the wing to provide strentgh.

All together 3 screws were used. One to hold the front portion down, seen in the first pic below, and two to hold the back portion down.

Wing Tip Floats Attached
Wing Tip Floats Attached
Wing Tip Floats Attached Side View
Wing Tip Floats Attached Side View

Building Seamaster Day 58 & 59: Painting

Fuel Tank Assembled

April 28th, I painted the pylon and applied the base coat to the fiberglass cassing. I then went with yellow paint for the pylon to match the top color of the aircraft (wings and stab are yellow on top).

Pylon Base Painted
Pylon Base Painted

May 1st, I mixed up a batch of epoxy and attached the throttle servo assembly previously made to the pylon, using clamps to hold it in place while the glue set.

I then spray painted the fiberglass cassing it’s first coat of green paint. Prior to painting a piece of frog tape was wrapped around (darker green in the image below) so that after an appropriate amount of coats have been applied and the paint has dried the tape can be removed providing a white stripe to accentuate the piece.

The green was spray painted on so the encasing was placed over a ‘stick’ and clamped in a vise which was placed inside a cardboard box (with the one side cut out) to contain the paint. Rotating using the vise, periodically, to achieve an even finish… roughly 🙂

Building Seamaster Day 56 & 57: Engine Mount & Anchor

Throttle Servo Mount

On March 31st I worked on getting the the holes drilled into the engine mounts for, you guessed it, mounting the engine. This involved figuring out the size of bolts I’d be using and finding the correct drill bit size. Next, I needed to figure out where the holes needed to be drilled that would allow enough room for the engine to fit comfortably (not to far back/forward) allowing everything to function properly.

Once done I bolted the engine on ensuring everything fit & looked good. The final product can be seen below:

April 1st I made the throttle servo mount, seen in the featured image at the top, using up some scrap pieces that work just perfectly for the job! Needed to make sure they were spaced accordingly on the back plate to allow me to screw the servo down.

Next, I created an ‘anchor line’ for the engine, which involved using some fishing lure wire and clasp as well as a metal holed enlit piece (my technical terms are eluding me today!). To do this I slipped the end of the wire through a clasp, then through the one eyelit of the metal piece and back through the clasp, pulling to ensure the correct size. I then bent the metal clasp so the one end can be bolted snugly to the bottom of the engine mount.

The wire serves the purpose of anchor the engine to the fuselage encase of a crash into the water to prevent the engine from sinking. Hopefully can get to the down aircraft before the fuselage does!

That wrapped up another couple days of building.

Engine Anchor
Engine Anchor

Building Seamaster Day 55: Pylon & Firewall

On March 23rd I worked on getting the firewall and pylon prepped to take the engine and the servo to control the throttle.

This involved gluing in a triangular piece for… as well as a rectangular light balsa block which is where the servo assembly is going to mount too. I took the measurements for the two pieces from Peter’s Seamaster, drew my measured lines on the wood, cut the pieces down to size using a table jigsaw and sanded where necessary.

Mounting Plate And Pylon
Mounting Plate And Pylon

On March 26th I continued getting the firewall ready by drilling holes in the firewall for the engine mounting brackets. Once the holes were drilled I installed the T-nuts. The steps to do this were:

  • Fill the center of the T-nuts with Vaseline
  • Apply glue inside the hole and on the back around the hole
  • Hammer in the T-nuts
  • Wipe away excess glue
  • Clamp and let dry

You can also see in the first picture below where added supports for the previously installed triangle piece was glued and is also now screwed into the firewall too.

Mounting Plate Drilled For Engine Mount Back
Mounting Plate Drilled For Engine Mount Back
Mounting Plate Drilled For Engine Mount
Mounting Plate Drilled For Engine Mount

Building Seamaster Day 54: Push Rods, Linkages & Support

Push Rod Linkage to Servos

On March 17th it was about push rods, control horns and linkages.

The first step was to get the push rods in place and attached to the servos (like you see in the featured image) all in there neutral position, the one isn’t… and may have lead to a correction being made later on if I’m not mistaken. In the image you can also see the hardwood glued into place to support the servos that have been screwed into it to keep them firmly in place during flight (so we hope). 🙂

When dealing with the push rod for the rudder, seen in the picture below, need to figure out where the control horn (the white piece attached to the rudder) needs to go to be in line with the rod coming out of the fuselage. Secondly you need to make sure it is in a place where it can be securely fastened, via screws, to the rudder. There is a back plate on the other side that the four screws pull in causing the front and back pieces making up the control horn to come together like a ‘clamp’ on the rudder.

Once the horn is in place, I then needed to figure out where to cut off the push rod, specifically the fixed outer casing (in black) and the inner yellow rod (actually moves) in order to have full motion of the control surface, which in this case means full left and full right on the rudder.

The control linkage (the metal part I screwed in earlier to the yellow push rod) then needs to be adjusted by screwing in/out so that it attaches to the control horn with the rudder in the neutral position. Don’t forget to ensure the servo arm (see top picture) is also in the neutral position as you want to have full range of motion for pushing and pulling the control surface.

Rudder Push Rod, Linkage to Control Arm
Rudder Push Rod, Linkage to Control Arm

Prior to attaching the elevator control surface the outer casing for the wire was attached to the ‘arch’ in the stab, but due to a design flaw (?) a wedge needed to be made and place under the casing since there was a requirement for it to be raised higher up off the stabilizer to connect properly to the elevator and be able to gain full motion.

Though a traditional push rod was not used, instead a piece of metal wire was fit through the tubing, a similar process was followed with figuring out where the control horn needed to be and making adjustments for proper attachment of the control linkage. This is seen in the pictures below and again ensuring the elevator and the servo are in the neutral position.

Tubing, Control Horn and Stab Supports
Tubing, Control Horn and Stab Supports
Elevator Linkage to Control Horn
Elevator Linkage to Control Horn

Lastly, due to an actual design flaw you will see two support wires that I attached from the bottom of the fuselage at the tail to the bottom outside edges (where there is balsa to screw into for support). Thanking to John V. for making the linkages for me… I believe it was out of fishing lure materials.

This is necessary as it was found that the tail of the aircraft, specifically the stabilizer would flex on the fin to much and not function as intended to provide stable flight.

Building Seamaster Day 53: Covering Sides & Tubing

Covering Fuselage Front

On March 12th I completed the covering of the sides of the aircraft in white. This involved cutting some over-sized white covering for each side and ironing it on, again about a quarter inch over the exiting covering. Started with lining up the straight edge with the edge of the black paint on the nose to give a cleaner looking finish.

Once ironed, trimmed the excess to be flush with the top and bottom.

Since this is an aircraft for the water need to ensure anywhere water can get in is sealed. To facilitate this for the control wire that is going to work the elevator tubing was run from within the fuselage up the leading edge of the fin and towards the back of the stabilizer. This process has not been completed yet… stay tuned!

Elevator Control Tube
Elevator Control Tube