DH108 Swallow for QX-30 EDF

This is a small and agile scale model of the famous British experimental jet for experienced model pilots. It is economical to build in LW-PLA (only 135g needed) and takes a print time of 18 hours and 20 minutes.

Designed specifically for the QX-motor 30mm electric ducted fan, it has excellent performance and with a balanced fan even sounds quite "jet-like" in flypasts. It is aerobatic and quick, so not suitable for beginner pilots.

This download contains the Printing and Assembly guide for the model plus .3MF and g-code files for the model, sliced in the free Prusa slicer. This design has not been tested in other slicers, but for those who cannot use the g-codes directly there is a jpeg image in the download package that shows the basic settings from Prusa which could be a starting point in other slicers (such as Cura). Prusa is recommended though, as it will populate all the print settings from the .3MF files.

There is also a .PDF file with markings for the full-size aircraft VW120 which broke the sound barrier in 1948.

SCALE 1/19.5

WINGSPAN 611mm (24 inches)

LENGTH 415mm (16.5 ins)

FLYING WEIGHT 250g +/- 10g depending on battery (8.8 ozs)

WING AREA 6.85 SQ DM (106 SQ IN)

WING LOADING 36g/SQ DM (12 OZS/SQ FT)

DUCTED FAN UNIT QX-motor 30mm EDF 7000kv version

LIPO 3S x 450mAh to 850 mAh

RECEIVER 4ch full-range micro Rx

SERVOS 2 x 4.4g (max thickness 8.5mm preferred)

VIDEOS:

https://www.youtube.com/watch?v=DbczI3BCzlQ

https://www.youtube.com/watch?v=WrWgqZ7YjHI

https://www.youtube.com/watch?v=6OnY-WUlbwM

https://www.youtube.com/watch?v=HPxFKO8uhfw

https://www.youtube.com/watch?v=QKwFYewLgwc

RCGroups thread:

https://www.rcgroups.com/forums/showthread.php?4485981-Mini-DH108-Swallow-for-QX-30-EDF

Timeless Wings home page:

https://timelesswings.com/

EDIT: 24 April 2024

Added the gcode and .3mf files for two variations of a new optional hatch which incorporates a cheater inlet, to provide more static thrust when hand launching in still air conditions. Please see RCGroups thread for details, post #202 onwards.

https://www.rcgroups.com/forums/showthread.php?4485981-Mini-DH108-Swallow-for-QX-30-EDF/page14#post52415883

There is a video showing launch performance with the new cheater here:

https://www.youtube.com/watch?v=5IiW9QzycLI

The files "plain cheater" have the holes in the cheater grill open, which will result in light stringing using LW-PLA filaments. This can be cleaned up as usual with a sharp knife, sandpaper and a file.

The files "webbed cheater" have a 0.5mm thick webbing added to the inside (lower) face of the cheater grill, which prints much cleaner, but requires the webbing sections to be removed with a sharp blade after printing.

Several iterations of each of these have been printed. If you are using a filament that oozes lots in the printing then it may be easier to use the webbed files (no clean-up really, just cutting the webbing out).

EDIT: 27 March 2024

Two new files added (hook_3mf and hook_gcode) for a bungee hook that can be printed from PLA+. This is to provide an alternate launch capability when hand launch is not desired or not possible.

The new attached /jpeg images show the location of the hook central on the underside of F1, with the rear of the hook level with the rear of F1.

A video showing the Swallow bungee launching is here:

https://www.youtube.com/watch?v=NKtAX9yAv3g

EDIT: 13 March 2024

jpeg image added to download package containing suggested print settings for those not using the g-codes directly or the Prusa slicer.

EDIT: 9 March 2024

2 alternate files are added (hatch_long_3mf and hatch_long_gcode) which provide a very snugly fitting hatch, if the original hatch has too much slop. This alternate hatch is about 1mm longer, and allows for variances in the printing process. This hatch seems to give a more reliable fit than the original.

This model has been designed in Rhino 7.0 and sliced in Prusa 2.6.1.
It has not been tested in other slicers. The provided G-codes should work on a cartesian printer of minimum size 200mm x200mm x200mm. If the gcodes cannot be used, all the print settings are contained in the .3mf files when loaded as a project into the free Prusa slicer.