Tag Archives: Building Aero 3D

Building Aero 3D Day 7: FUAs Glued & FUH

Balsa Glued to Stringers (FUAs)

Peter came over this afternoon and we made progress on building the aircraft. Today we completed Step 3 and made progress on Step 4. If anyone is curious, for the fuselage there are 11 steps total of which Step 10 is a biggy.

Peter brought over a bunch of balsa block scraps we could use for positioning/stabilizing the doublers (FUAs) along the balsa stringers. We started by figuring out what we would need and where, including heights, and making them. Used some CA to glue pieces together, then cut them out and sanded so they’d fit flush to the sides. You can see the pieces we made in the featured image at the top. We also slid some pieces underneath the stringers, as they are raised off the surface, to ensure the balsa stringers are snug to the top of FUAs.

Oh yes, technically it is the top as the fuselage is getting built upside down, encase you’re wondering.

We also took a look at how we’d be gluing FUH in place and cut an additional 14” x 12” balsa block with a length of 1 1316” to support the middle (ensure it is glued level). We used some thin CA to hold the piece in place, planing to break the glue joint and remove it once FUH (FUG on the actual piece) is set.

With a plan in hand I marked where the formers sit on the stringers and where the front ends fit into the FUAs and then mixed up a big batch of glue. I then applied glue on the front ends and top of the end of the balsa stringers along with where the formers are going to be sitting. Once that was done I placed glue along the top (technically) edge of the doublers and in the notch where the balsa stringers fit.

Once all the glue was applied we placed the piece on. Getting the stringers tight up into the FUA slots and flush with the outside. We slid some sticks and sanded down balsa pieces to make wedges for under the stringers to ensure the FUAs and stringers were tight against each other. We could see no gaps along the length so added some weight on top to hold everything in place.

You can see how we left things in the featured image above. How the balsa blocks used to make sure the sides of the FUAs are flush with the sdie of the stringers are wrapped in wax paper (to ensure they don’t get accidently glued together). This is also on the far side to keep things in line there as well.

The last thing for the day was gluing FUH into place, seen below. All that was needed with the additional support in place was some glue along the front edge and on top of the back balsa block. I also used the square to help ensure it was centered as best I could get it.

Looking down the length of the fuselage we could see everything appeared to be lining up great and in position. This wrapped up our Sunday building session.

Tail Wheel Support Glued (FUH)
Tail Wheel Support Glued (FUH)

Building Aero 3D Day 6: Front Formers and Back Former Glued

FU2 to 6 Glued

This morning Peter came over and we tackled the remaining formers. We were very pleased with how the previous session set.

We started this session by completing Step 3 of the instructions; I use that term loosely with this build. The final result can be seen in the featured image above. I mixed up a batch of 30 minute epoxy and started with placing glue along the edges of former 5 (FU5). For all the pieces I avoided placing glue along the bottom notches as at this point we did not want to glue the doublers (FUA’s) to the balsa stringers. Once that was done we lightly clamped the piece in place.

Next, I placed glue along the edges of FU6, and during this process realized I never placed glue along the front and back of the tabs sliding into the doublers so backtracked and did that for FU5 and carried that process through to FU6 and onward as want to make sure there is glue on every surface that is in contact with part of another piece. We then lightly clamped FU6 into place. This procedure was then repeated for FU3/4 and FU2.

When doing the two at the front we ensured that the spacing between FU2 and 3 was correct by placing the landing gear mount in between (temporarily) while additional clamps were put in place. For the FU3/4 pairing we utilized two clamps, one for the top as it seemed to want to spread outwards and one for the bottom to ensure everything stayed in place.

It is worth noting that prior to tightening and as we tightend down the clamps we looked down the front of the fuselage to ensure all the formers were still lined up on the center line and doublers squared up against the block of wood.

We then moved to the tail where I glued former 10 (FU10) into place and left the square in place to ensure the piece remained vertical (that is squared up). The last piece glued was (from step 4) FU-ST-9, which is a piece of balsa 14” x 12” cut to 1 1316” length from some scrap pieces Peter kindly brought over to start my scrap collection, perfectly suited for tasks like this! Same process here of marking the center on FUF and the balsa piece, even though we know there is going to be overlap, this ensures equal overlap on both sides, just encase.

From what we can tell of the diagrams FU-ST-9 will eventually be sanded down to be flush with the outer edges of FUF. For both Peter & I this is a new way of building (as there are no plans or additional instructions beyond these basic diagrams) so some discussion and me cracking out the manual online so I could zoom in on the PDF which allowed us to realize that coming up in Step 4 FUH is sitting flat, butting up against FU10 and on top of FU-ST-9, instead of the angle it appears to be in the printed version of the diagram (which didn’t make sense). FYI, in the kit FUH appers to actually be the piece labeled FUG.. though FUG is suppose to be hardward… this is 18” ply.

That concluded another session, as we could touch nothing else until the glue dries.

FU 10 and FUST 9 Glued
FU10 & FUST9 Glued

Building Aero 3D Day 5: Formers 7-9 Glued

Formers 7-9 Glued Close-Up

Yesterday, Peter was over and we got to work assembling the fuselage by determining what we can get done in which sessions. What we essentially got done this day was Step 2 (minus installation of former 10). I did start by sanding the excess glue off formers 3&4, previously glued together, drilling out the wing dowel bolt holes (so the dowels will fit through nicely), and cutting out the excess glue from the three slots in the top of the formers.

In order to get the back formers glued into place we had to assemble the formers (except the firewall F1) and doublers at the front as well, clamped into place to aid in determining spacing of the back formers. I marked the centers on formers 7 through 9 (F7-F9) using my centering ruler. The balsa stringer is elevated off the table when slotted into place in the doubler so we used some excess 14” x 14” balsa along with an excess 18” ply piece wedged under the stringer near the front (in the image below) ensuring everything was flowing from front to back correctly. I did have to do some very light sanding of one balsa stringer end at the back to ensure a proper fit with the tail piece (FUF).

It is neat, how if you have everything lined up and straight the placement of the formers is just where they fit (that is where the balsa stringer fits properly in the left and right slots on the bottom of the former). The diagram based instructions tell you nothing about measurements of where things should be.

You do need to make your own measurements though… this is where the previously made chalk lines come in handy. Ensuring the center marks on all the formers are lined up on the chalked center line on the table you measure from the nearest perpendicular chalk line to the former on each side. If the two measurements are equal then you know things are squared up that way. We did have to make some adjustments and added some aditional pins to help aid in keeping everything aligned.

Once places were determined I traced a pencil line on the balsa in front of each former and marked the back side with an ‘x’ (where the former goes back to). It was now time to glue.

Starting at the back I placed glue along the front edge of FUF and then placed it back between the two balsa stringers ensuring everything was snug and pinned into place. After placing glue on the corner slots of F9 I placed it into position using a square to ensure it was sitting verticle, the center lined up on the center chalk line, and a ruler to measure the distance of each edge from the nearest chalk line to verify they were of equidistance. This process was then repeated for F8 & F7 in that order.

Once all pieces were glued in place we verified everything was sitting properly and then touched nothing… well there was some fumblings and resets inbetween ;).

You can see in the image below that a case of beer can be repurposed :D. The block of wood helped ensure the front of both doublers were even.

Formers 7-9 Glued
Formers 7-9 Glued

Building Aero 3D Day 4: Joint, Trials & Former Gluing

Scarf Joint

Wednesday Peter came over after we both had some time to contemplate what we were missing the session before. Due to my lack of experience I would have been hard pressed to come up with the correct answer; however, Peter determined what the diagram was trying to tell us and that was…… *drum roll please*…. a scarf joint!

As you can see in the featured image above the length of the balsa stringers needed to be extended/strenghtened via a scarf joint. The way this work is you want the joint to be 8 to 10 times the length of the thickness. In this particular case we are using 14” balsa and Peter made the joint length 12 times the thickness. Which is 12x14“=3”. This is cut at an angle from the top at the measurement to the bottom at the end of the balsa stringer (repeated for the piece that is going to fit on top).

We re-pinned everything down and in the next session, hoping, we will actually glue what we trial fitted last time into place. This session, however, we did some more sanding to make sure all the pieces were ready.

To ensure the balsa stringers are flush with the outer edge of the doubler we measured and cut a 14” x 18” piece out of the bottom corner of former four so half the stringer width fits underneath.

Lastly I glued formers 3 and 4 together using 30 minute epoxy and clamped it into position, as seen in the image below.

Formers 3 & 4 Glued Together
Formers 3 & 4 Glued Together

Next time will hopefully be getting the formers and doublers glued into place on the stringers.

Building Aero 3D Day 3: Fuselage Contemplation & FUDA’s

Fuselage Conundrum

Yesterday Peter came over to assist with getting the fuselage situated. He brought a china marker (white) to make a straight line on the table, providing a center point for the fuselage. I marked the center on the bottom of each former so that we could ensure the fuselage is center properly.

The very tail piece was center and pinned into place at the far right (matching the diagram instructions) and two 14” x 14” balsa stringers were pinned in place. Based on the diagram I figured the spacing would be determiend by this step as they do not state how far each former needs to be from the next. When we placed all the pieces together as shown in Step 3, FU 2-10, and campled them into place (no gluing, this is purely a dry run) we determined that this was not the case and to top it off couldn’t figure out how the stringers were to fit into the slot of the front side pieces (FUA’s) as from what we could tell the outer edge should be smooth; however, the stringers definidfely protruded at the front… even though we never cut it down to size, this wouldn’t have mattered for this case. We did, however, move the ‘front assembly’ back and forth along the stringers to see if we could make sense of the situation. The side panels of the aircraft are to be 51 inches long so we were trying to get all the numbers to work out based on the lenth of the tail wheel plate at the back of the fuselage, the stringers (FU-ST-1 – which are suppose to be 37716” in length), and FUA’s (believe these to be the doublers for added support to the engine block, etc. at the nose of the aircraft). We seemed to be 2″ short and didn’t think this was accounted for by the forming/fitting of the side panel to the formers.

These steps are critical and need to make sure everything is positioned correctly along the stringers and at right angles; because if it is off at the back it will only get worse as you move towards the front, each step along the way exacerbating the situation (that is potential twisting/warping of the fuselage). You can see how we left things in the image at the top. We decided to pause and let things perculate for a while. If you are not sure then don’t proceed. Will likely get some additional input from other modellers before moving forward… stay tunned.

What I did get done this day, besides contemplation and discussions around the fuselage, is gluing what appears will make up the landing gear block (FUD & 2 FUDA’s stacked on top) glued together by mixing up some 30 minute expoxy. You can see them clamped together drying below:

FUD & FUDAs Glued
FUD & FUDAs Glued (Make up landing gear block?)

In conclusion, though this day was not as fruitful as we were hoping, troubleshooting/problem solving and discussing with our fellow aeromodellers is part of what this hobby is all about!

With luck, I’ll be able to make more progress later this week.

Building Aero 3D Day 2: Formers and Balsa Gluing

FUD and 2 FUDA's Sanded

Today I made some more progress on the fuselage of the aircraft. I started by cutting, from 1/4″ x 1/4″ balsa stringer, two pieces for cross braces in former 7 which was 2116” and in former 8 which was 1516“. Once cut I used medium CA, placed on the ends of the balsa and top and bottom where it wil be making contact with the former.

I inserted the balsa piece into the former and pinned in place (the pins kinda seemed uncessay as medium CA dries very quickly). I did this over wax paper to minimize my chances of getting glue onto the pinning surface of the workbench. The result is seen in the bottom left picture.

Next I cut out formers 3 and 4 out of the 18” ply and sanded the exterior perimeter, except the curved (bottom) portion of FU3 as nothing will be gluing here. The idea behind sanding (to my knowledge) is to remove the laser burn and create a surface for the glue to more easily stick… also removes the rough jut outs from where I cut the tabs holding the pieces into the main ply sheets.

Lastly I cut out the two FUDA’s and removed the plastic wrap around a bundle of pieces to get FUD. The two FUDA’s are going to get glued together and then glued to FUD. Looking ahead in the instructions these pieces when inserted into the bottom of the fuselage between formers 2 & 3 are going to make up the mounting point for the landing gear, as the wires will be recessed inside… stay tuned for when I get there (Step 10)! You can see them sanded in the featured image both along the external perimeter as well on the internal perimater for the FUDA’s.

That concludes another building session… stay tuned as I plan to get steps 1 and 2 fully completed soon!

Building Aero 3D Day 1: Sanding at the Rear

Aero 3D Fuselage Plan

Winter is upon us again… that means it is back to building season! This build is going to take on a bit of a different dynamic as a big thank-you goes out to Peter & John for helping me build a workbench in our mudroom. I’m excited to be able to go at my own pace from home and see how well I do as it’ll be less structrued and me troubleshooting alone along the way… that said the guys are not far away if I require assistance!

Speaking of, on Nov. 17th Peter came over and graciously leant me some tools to get me started. We looked through the kit, explorered the manual, came up with a game plan as to how to approach this build and interpret the diagram based building instructions. Mr. Aerodesign approaches things differently. More thoughts on this in a future post once I have more experience.

The aircraft I’m building is an Aero 3D, which should allow me to get into 3D flight (also good for smooth flying) as the thick airfoil and oversized control surfaces give this aircraft exceptional flight caracteristics, supposedly and what I’m hoping to find out! 🙂

Throughout my posts I am going to describe the pieces as I think they are with the labels Mr. Aerodesign provides in the manual, i.e Former 7 (FU7).

While Peter was there I cut out a half dozen pieces from the two 1/8″ ply sheets to start the rear of the fuselage. Specifically formers 7-10 (FU7-10)

On Nov. 18th I gave all the aforementioned pieces a light sanding to remove the ‘laser burn’, which helps the glue stick. Need to make sure you don’t oversand; otherwise, where the 1/4″x1/4″ balsa stringers fit into, or other parts go together, will be to loose.

I skipped step 1 as it requires some gluing, but will prep those pieces and do some gluing once my supplies arrive!