Summary

This sword is about right for your 2 to 6 year-old dragon-slayer. Adult-sized version also available.

Instructions

In addition to the printed parts, this sword uses a length of foam pipe insulation (0.48" ID, 1.25" OD)and a 1/4" (or maybe 6 mm) diameter rod or dowel (I used steel, but wood would work) and hot glue or other adhesive of your choice.

Print the handle and the blade plug. The handle will benefit from support at the blade stud. Don't worry about surface finish there; it gets covered up anyway. The full tang means your handle shouldn't need to be super-sturdy, but I printed at 0.2 mm layers and 100% infill because my kids are hard on things.

The "big-hilt" file is adult sized. I was jealous of my kids' swords. Construction is otherwise identical.

Drill out the holes if needed to fit your rod. Cut the pipe insulation to the desired blade length (roughly 18"). Cut the rod to length (handle length + blade length - 2 inches). Note that the blade will overhang the rod when the rod goes all the way to the end of the handle, to make a soft point.

Place some hot glue inside the plug and run it over the rod, until the rod is flush with one end. Put some hot glue in the hole in the handle and likewise run the rod in until it's flush to the bottom (it's a full tang). There are recesses inside the handle and plug to hold glue, so you can use a fair amount.

A caution: hot glue will melt some pipe insulation, so don't use too much during assembly.

Place some hot glue on the handle stud and run the pipe insulation over the plug, over the rod, and up to the hilt of the handle. The plug should be recessed by that 2 inches, leaving a soft "point" for the blade. With the blade vertical, squirt a little (not too much) hot glue down that hole to bond the blade to the plug. Wait for it to cool before playtime.

Now have fun storming the castle!

Toy sword - foam blade