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**BobM** · 07-11-2018, 02:15 PM

A quick note about the building board and building process here....be sure the building board is flat and level. Also be sure to have squares and other materials to help with keeping the assembly square through the build.

The build starts with the tail group...first are the vertical fin and rudder assemblies.

These are the parts for the vertical fin and rudder. All parts are well labeled and the fit is excellent due to the quality of the laser cutting that Peter does.

Both the vertical fin and the rudder are built with ribs that are glued to a 1/64" ply center skin. The skins have laser etching on them marking the position of the parts. This makes it possible to construct everything on the building board without having to layout on the plans.

The base rib is put in place first and it is important to make sure it is 90 degrees to the building board.

The vertical sheer webs are used to space the ribs from there. They are tapered. I used my small square to determine the edges that are 90 degrees so I installed them correctly.

The rest of the ribs are put in place and then flip it over and repeat for the other side.

This is the completed framework with the front and rear subspaces in place. Once this is completed the sheeting is then glued on along with the front leading edge and rear edge.

After the glue is set I shaped the leading edge. I like to use a skew block plane for shaping long runs of wood such as the leading and trailing edges of the parts. It helps to keep the edges straight and consistent.

This is the completed rudder, assembly is very similar to the vertical fin. The last step will be to make the bevel on the hinge line to complete the work. Again I used the slew block plane for doing this (I typically draw the hinge line on the wood and make guide lines with a steel rule, then carefully plane the wood close to the guide lines, finishing with some final sanding).

**BobM** · 07-11-2018, 02:56 PM

The next step is the horizontal stab and elevators.

All the parts for these assemblies are set out and organized first, which helps with the building. Again, I built these assemblies on the building board and used the plans as reference.

I saw a great way that Peter does his building by using Saran Wrap or similar cling wrap to cover the building surface first, this prevents and glue from getting on the building board and makes it easy to pick up the glued parts afterward.

I built the framework for the horizontal stab by working from one side to the opposite. The first rib is put in place on the spar square and vertical, then use the sheer webs to space everything out properly. The build goes very quickly this way. Front and rear subspaces are in place and the top main spar has also been added.

I did add a couple of triangular stock supports for the alignment pin guide. I'm sure it isn't needed.

After the top and bottom subspaces are all in place the sheeting is then applied along with the cap strips. The leading edge is glued on and then the leading edge is shaped to match the profile. Lots of shavings from planing the leading edge here !

After the horizontal stab is completed I moved forward and started work on the elevators. They are assembled on the base, which has laser etchings to show rib placement.

I assembled them and did not put the top on until later, as I wanted to be sure of where the control horns would be installed as well as how I would install the hinge plate.

The hinge plates that go on both the horizontal stab and the individual elevators have hinge supports installed on them. I found the easiest way to put them in the correct position was to use a drill bit of the correct diameter to position them on the hinge plate.

I use the drill bit to put the support in position, then hold the support and remove the drill bit. Thin CA was then used to glue the support to the plate.

The hinge supports have a larger diameter than the spacing of the rear subspars on both the horizontal stab and the elevators. I thought about this and came up with a way to cut them down consistently and keep the centerline for the hinges right on the centerline of the stab and elevators.

I set up my table saw so the blade was the exact height of the hinge supports. I then adjusted the fence so the blade would cut just a fraction of the sides of the hinge supports off. I did this a step at a time, very carefully so the amount cut off would be the same on both sides of the hinge plate.

I would cut a little at a time until I could dry fit the hinge plate with the supports into the rear of the horizontal stab. Once the fit was completed I set this aside and did the same for the elevators. Note that I did not glue anything in place yet...I wanted to make sure of the final placements of the hinge plates on the stab and elevators to have the correct spacings.

The elevator spacing between the rear subspars is narrower than the horizontal stab spacing. I did the same process as with the horizontal stab and was able to get a very good fit.

There are ribs and other parts that require some trimming of the hinge supports for a proper fit. This can easily be done with everything open.....very helpful to not attach the top sheeting until a bit later.

At this point I assembled the supplied control horns. These are on a laser cut sheet and are laminated into finished control horns using 3 laminations. After the control horns were completed I slotted the elevators for the control horns.

The sheeting was then glued onto the elevators once I had a good fit for everything. Then I put the hinge plates into the horizontal stab and elevators (without glueing yet). I was able to make sure of the proper placement of the hinge points so they aligned properly and also adjust the side to side placement to have everything centered properly. Once I had this set I made small marks as guides and was ready to glue the hinge plates in place.

Some final shaping and sanding after all the glue set and the tail surfaces are set aside for the final assembly later on.

Attached Files

**BobM** · 07-11-2018, 03:03 PM

The wings are next and I started with the right and left center sections.

Again, I built directly on the building board and used the plans a a guide. I also used a variety of right angles and squares to keep everything aligned properly.

**BobM** · 07-12-2018, 05:16 AM

Finished framing out both center panels today. Just need to add some sheeting and cap strips then finish up the final work on the flaps tomorrow morning. The outer panels are the project for the rest of tomorrow. More pictures tomorrow.

**kjkavaney** · 07-12-2018, 12:38 PM

Great write up and inspiring pictues Bob...you are a building machine !!!
kevin

**BobM** · 07-13-2018, 02:14 AM

Center panels are completed...finally !

Seems like it always takes longer than expected, but the results have been very good so far.

I have to give another shout out to Peter and the design of this kit...it is really well thought out and the parts fit is excellent due to the care of the laser cutting. The wood is excellent and has been selected carefully.

Here is the work progress so far....

The center panels were sheeted on the bottom first, then I spent some time installing the hinge supports carefully before sheeting the top of the panels. The hinge supports had to be cut to fit properly due to the internal wood structure of the panel at the trailing edge. I looked at the plans several times before attaching the hinge plate on the back side of the panel....the alignment as well as orientation needs to be determined for both the right and left sides.

After I had the panels completed I started on the flaps themselves. I made right angle blocks out of some scrap wood from my shop on my saw so I could set the ribs at right angles throughout the process. I made 4 of them with the specific spacing of the ribs for the center panels (same spacing as the ply front and back sheer webs used in this part of the construction), this made it easy to set the ribs properly during construction.

The flaps have hinge supports installed like the elevator and center panels. I did a similar process to what I showed for the horizontal stab and elevators. I completed the flaps up to the point of having them remain open, without attaching the top sheeting until after all the internal work is completed and fit properly.

Using the correct diameter drill bit (11/64") I dry fit the supports. The picture above shows the flap with the hinge edge up. The mark is the balsa height inside the flap.This allows me to measure the correct cut point on the hinge support and then dry fit it. Once I was happy with the fit I installed them one at a time with thin CA.

These show the fitting of the hinge supports inside the flap. Once the supports are installed I then attached the top sheeting to the flap and did a quick sanding to clean things up. Note the flap control horn is installed internally in the flap and extends through the flap hinge plate.

The flap has to deflect up to about 40 or 45 degrees (peter's notes suggest 12 degrees for take off and 42 degrees for landing). The bottom edge has to be chamfered to allow the motion of the flap downward. I marked the hinge line on the back of the flap and used a 45 degree angle to draw out the chamfer. Using the skew plane I was able to make it pretty quickly and then just a quick sanding to finish it off.

These show the flap in the upward and downward positions showing the chamfer that allows movement of the flap.

The finished center panel with the flap deflected downward (I have a couple hinges dry fit for testing the motion of the surfaces). The slot on the right side of the hinge panel is the flap control horn.

Onto the outer panels now....hopefully between tonight and tomorrow I will have those done.

**kjkavaney** · 07-16-2018, 08:36 PM

Good work Bob, you seem to have avoided some all my mistakes...good luck on the outer panels which is where I really got in trouble with ribs twisting progressively a tiny bit on the spar...I think I am the only one who has screwed them up, Jim Dolly and others seemed to breeze through this build as well...wish I could start the wings over...

**BobM** · 07-17-2018, 05:53 AM

I finished the inner wing panels up the other day and have been working on the outer panels for the last several days. The inner panels turned out well.

Here are the parts for starting one of the outer panels....ribs, spars, sheer webs, etc.

First thing I did before starting was to use my long straight edges and squares to draw alignment lines on my building surface. I made lines for the spars that extended from the left to the right edge and then made a line at a right angle for the outside rib of the inner wing panel. This made it possible to keep the inner panel and the outer panel spars carefully aligned while installing all the ribs and sheer webs. I used 1/8" balsa shims under the spars to have the correct height.

The first rib at the end of the dihedral brace was a starting point for my build of the outer panels. I used this to help with the alignment of the spars and to make sure eveyrthing lined up properly. Once that one was set I was able to glue the bottom spars in the correct alignment and start adding ribs one at a time.

The coffee can is full of lead shot and was used to keep the outer panel flat on the board during the build. I also braced the inner panel underneath to help with the alignment.

I decided the easiest way to keep things flat was to also add the read balsa spar and back sheeting. I laminated these together and was able to then glue the back of the ribs in the proper placements as I added them. I found the angle of the bottom rear edge and sheeting and then cut this so I could glue this into place while working on the panel.

I used the sheer webs and my square to keep everything aligned. All the ribs are at a right angle to the main spar.

After all the ribs were in place I used the sanding stick I had made when I started the build. This allowed me to sand the spar slot to be an exact fit. After the sanding was completed the spar was then glued into place.

The front and rear sub spars were added as well as the rear sheeting.

Sheeting the forward section was completed on the top and bottom and then trimmed and sanded to have a straight edge for attaching the front leading edge and the rear aileron mounting plate.

The next step was to shape the leading edge. I used the skew plane and when it was close to the profile I sanded with a sanding block to finish the profile. Lots of shavings from this step !

The cap strips were put in next. I marked the placement of each cap strip before cutting them.I used my adjustable angle and the square for cutting the edges to match. The were all installed on the top and bottom of the wing and then I did a final sanding of the panel.

Notice the aileron servo mount and mounting plate is installed. It is located between wing ribs 6 and 7.

One of the panels completed with sheeting and cap strips.

Both panels are completed now and the next step is to make the ailerons. Then onto the fuselage after that.

Attached Files

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