Cutting ailerons on a wing

When building a plane from scratch you first need to decide if you want ailerons on your plane.  Some planes do better without ailerons where on other planes they are a must. 

For this write-up I will be demonstrating how to install wings in a fully built wing.  Yes, I said fully built wing.  It’s important to fully build your wing right up to the point before covering it. 

In this picture we are installing ailerons in a scratch built Sig Kadet Senior.  These plans were shrunk to a 38” wingspan.  

   

The first step is to measure and mark where you want the ailerons to be.  In this case, since this is a simple trainer, we want smaller and longer ailerons.  If it were an aerobatic plane we may consider larger surface area ailerons for more throw.  Notice how I have marked the ribs where the ailerons are to be cut.  I will not get into how big and whereabouts to cut your ailerons as this will be your choice and discretion.  Just be sure to mark both wings the same so they match perfectly.

Next step is to cut out the aileron.  Using a blade shown in the pics, make a straight cut up and down.  Be careful and be sure to pay attention where you are cutting these as you would hate to mess up a freshly built wing.  I mean come on, it took you at least a month of building. 

Now it’s onto putting the wing back together.  Using a thin strip of balsa that is the same height as the inside ribs, cap off the inside so that the inside is secure.  Depending on how even you cut your ailerons you may need to sand these down a little to get the straight.  Also, be sure to cut them back to compensate for the thickness of the balsa cap that will be applied to the ribs and also the aileron or the ailerons will stick out and this would be ghetto.  We don’t ghetto build around here.

After you have capped both insides of the wing its time to cap the ailerons. You will be cutting these at a 45 degree angle.  If you cut them straight they will not be able to pivot.  Once you have cut them and sanded them even cap them with a strip of balsa.  See picture below.  Do this to both sides. 

Now its time to hinge them.  You can buy different size and kinds of hinges.  For our application we will be using Du-Brohinges.  They seem to work really well as they are very light and have small holes to bite onto the CA. 

Install small plates on the wing where you want the ailerons to attach.  I have found two to three hinges will hold it just fine.  Be sure to mount the plates a little below the top of the rib as you will be capping this later and want to leave enough room for two plates and the aileron in between.  Go ahead and glue the wood caps in place but DO NOT glue the hinges in place.  You will install hinges after you cover.  Just be sure that they slide in and out with little force.

In the next article we will look at how to control the ailerons.