Printing and assembly of the Fokker DR1 Wing Struts.
Printing: All of the struts need to be printed using 100 percent infill. Standard PLA is just fine for these as you will be reinforcing them all with a 2mm. carbon fiber rod. Note: Ensure your prints are accurate to allow room for the rod to slide down through the part. Check your horizontal expansion, and hole horizontal expansion print settings to dial this in.
There will be a forward and back, left and right center strut to print. There will also be a new left and right retainer to print. It is illustrated below:
This image shows the tops of the two center struts as they come together. Note that there are 2 mm. carbon reinforcing rods that you will CA glue in place. Leave them long for now.
This image above shows the added retainer that slides over the flange of both forward and back center strut, holding the M-2x12 screw for mounting to the top wing. The image below is of the upper wing servo mount from the underside. You will notice the two holes where the center struts slide into place. Notice the brass 2mm heat set insert thread between them for attaching and removing the top wing.
The image below is of the forward firewall. You can see how the carbon rod will extend through a hole in the firewall for added support. The forward struts are to be epoxied in place to the fuselage. Do not do this until after the model is covered. Once epoxied in place the carbon rod can be sanded flush to the fire wall.
The image below illustrates how the rear center strut attaches permanently to the middle wing attach fitting. Again this will be epoxied in place after the model is covered. Also note that the latest version of this attach fitting sports a hole for a female servo extension lead. This is a simplification over the disassembly of the aileron servo lead designed earlier.
Printing: 100% solid infil. PLA is fine for this part.
The outer struts consist of an upper and lower strut for both the left and right side. There is a carbon rod that passes through the mid wing and both of these fittings. After covering, these struts will be permanently attached to the mid wing. On the top and bottom you will need to heat set a 3mm threaded insert into the struts so that a 3mm x 20mm nylon screw can attach and detach the upper and lower wings. See section view below: