Stab-safe printable LARP rondel dagger

Hello

 (v3 uploaded now with an improved connection for the back plate)

After I made a larp safe parrying dagger last year I challenged myself to design a fully safe stabbing dagger for conquest of mythodea this year. The result is both safe to hit people with and safe to get hit on for other (non printed) blades. 3d printing offers extra possibilities for a level of detail not possible with foam crafting and a level of customization not possible with moulded larp weapons. The pictures show my personal customizations, the version available here doesn't have the personal text or logo's.

Yes really stab safe

Warning: This is an experienced and expensive filament build, do not try this as your first big 3D printing (larp) project, you might get very frustrated trying to print TPU.

Necessary items: 

• Items
  • Superglue
  • Liquid (not gel) contact glue
  • Flexipaint in colour of choice (old formula, the standard for larp weapon use)
  • Spray on glue
  • Acrylic paints
  • Flexipaint sealer gloss
  • Coloured wood varnish for the grip
• Filament
  • 60A TPU for the blade → I used filatech filaflex pro 60A
  • 98A TPU for the core → I used filatech flexfill 98A
  • Optional cheaper 95A TPU for the front plate, back plate, pin (and sheath), or use the 98A one instead
  • Light brown PETG/ASA filament for the grip (or PLA but think about heat resistance)
• Tools
  • Sanding tool for dremel/drill
  • Standard print cleaning tools (file, cutter knife, wire cutter, …)
  • Paintbrushes
  • Satin textured sheet is your friend, it helps a lot with TPU!
  • Nozzle cleaning (acupuncture) needles
• Sheath
  • (Soft) leather or fabric
  • Rivets or stitching tools
  • Hole punch or pliers
  • Button system of your choice (optional)

Start by reading up on printing with TPU filament. The 98A TPU I used has it's settings included in the prusa slicer, same for the 95A, the 60A had them downloadable for prusa on it's product site. Default settings for all those are perfect here.

TPU printing tips:

• Don't forget to untighten your extruder screw
• Load the 60A TPU by sticking it on a nozzle cleaning acupuncture needle, it is so soft on it's own that it won't load normally
• If you don't have a satin sheet use brims for all non 60A TPU prints, really!
• Dry that 98/95A TPU before (during) each print!
• Getting your printer to unroll the 60A filament might be more challenging than you think, it is very stretchable. If needed unroll it and arrange it in clean ‘lanes’ on the floor. It is what I do too.
• Satin textured steel sheets are awesome!

Printing instructions (for 0,4mm nozzles)

Blade : 60A TPU

Print the blade lying down on it's ‘back’ with the default settings provided by the supplier (on satin or textured sheet), 4 walls, floors and roofs with 30-40% infill at 0,15mm layer height is perfect. No need for a brim here. This part is the hardest part, really. Expect failures due to partially clogged nozzles and the general pain of loading that soft filament.

Core 98A TPU

Use 3 walls for the core at 5-15% infill. Softer tpu will give a too floppy blade, so yeah that more expensive TPU really is needed.

Back plate, front plate, sheath: 98A or 95A TPU 

All parts can be printed at 0,20 or 0,15mm layer height, use variable layer height for the pommel dome set to minimum. 2 walls and 15% infill (prusaslicer standard) is perfect.

Pin : 98A or 95A TPU 

Print the pin lying down with supports, you want strength in the length direction. Print at maxiumum walls so it is extra strong and solid. 

Grip

Print the grip standing up. I used a light brown petg for heat resistance and added minimal “fuzzy skin” texture in the slicer for more wood effect.

Assembly

Assembling the blade

Inject or spoon (I used a lab syringe with the front cut to be a bit wider) contact glue into the hole in the blade, then insert the core all the way. Some glue might come out on the surface of the blade, wipe that off. Then let the glue dry with the blade lying flat (you might need to add a little weight on top if it doesn't stay flat). 

Cleaning and painting

Clean all printed parts, yes you can use soft sandpaper and wire cutters to remove unwanted print artifacts on all TPU parts. Use files, cutters, sandpaper,  dremel sanding etc to clean the 98A and 95A TPU. Get rid of those layer lines etc.

Then glue the back pin into to back plate and glue to front plate to the blade, both with a bit of super glue. Then place both parts on their stands and spray them from a distance with spray on glue. Let the glue dry and spray again until all parts, top and bottom, are covered with glue. This step is needed for our (flexi)paint to stay in place.
Then paint the pommel, parying plate with 2-3 layers of flexipaint. You might want to mix that third layer of flexipaint with some metal acrylic and drybrush for extra effect. 

Then varnish the TPU parts (except the scabard) with flexipaint gloss sealer.

I ‘painted’ my grip with a dark wood varnish.

You can paint the sheath too, of you cover it with leather only the plate at the top will be visible. I use a gold permanent marker for this (alcohol based).

Assembling the dagger

Sand the top and bottom of the grip to remove excess wood varnish or paint and also remove excess flexipaint from the pin and core so both fit into the grip.

Glue the blade into the grip with some superglue, then do the same for the backplate.

Let it dry and spray all parts except for the grip with standard larp weapon spray against stickiness.

Assembling the scabbard

cover the scabbard print with leather or fabric of your choice, I riveted it because I prefer the rougher look. Don't forget the add something to secure the blade in the scabbard.

Maintenance

Gravity will make the blade bend under it's own weight when lying down, for that reason it is best to hang it tip down or keep it in it's scabbard when in storage.

I hope you enjoy your build, don't forget to show me yours by uploading a make

Link to my tinkercad drawing if you want to edit further