Line Reel

Click the button to download a Zip file with instructions and a full set of STL printer files to replicate this project:

Build the Line Reel (~80Mb zip file download)

A decent line reel is essential for flying a kite to any height above a few tens of metres. Simple hand reels, such as those shown on the GEAR page suit many flyers. Remember to always wear stout gloves to reduce the risk of burns should the line slip through your fingers.

This project shows how an electric fencing reel was modified to include functions for paying out, cranking in, locking and braking in a controllable manner. It also includes a steel loop for tethering to a ground stake. 

This project starts with a plastic Voss reel which is widely available. Although strong enough to deploy electric fencing wire where tensions are modest, it will flex under greater pressure. A useful feature of this reel is the cam lever which locks the spool by activating a spring-loaded plunger.

Original electric fence reel showing the lever that locks the line spool

Original electric fence reel showing the lever that locks the line spool

Another view of the original reel showing the weak open design of the handle and the release pin to change the spool

Another view of the original reel showing the weak open design of the handle and the release pin to change the spool

The first job was to add strength by embedding carbon fibre rods into the handle and sides using an epoxy casting resin. In addition, the plastic bar between the handle and spool shaft was fortified with a 3mm thick aluminium plate with studs that ensures a strong ‘grab’ with the resin.

Another view of the carbon rod inserts with side plate being clamped during bonding

Another view of the carbon rod inserts with side plate being clamped during bonding

Aluminium plate with studs for bonding to the side of the frame

Aluminium plate with studs for bonding to the side of the frame

The first job was to add strength by embedding carbon fibre rods into the handle and sides using an epoxy casting resin.  In addition, the plastic bar between the handle and spool shaft was fortified with a 3mm thick aluminium plate with studs that ensures a strong ‘grab’ with the resin.

The hollow spool shaft was also strengthened with carbon rods together with a central aluminium shaft that projected to act as a spindle for the line guide: part for this guide are pictured here.

Carbon fibre reinforcing rods glued in the handle prior to infilling with resin

Carbon fibre reinforcing rods glued in the handle prior to infilling with resin

Another view of the carbon rod inserts with side plate being clamped during bonding

Original electric fence reel showing the lever that locks the line spool

The original Voss spool cam lock was dismantled and a longer version made in brass on the lathe, then re-assembled with an old radio knob to add some style!

Dismantled parts of the original reel lock

Dismantled parts of the original reel lock

Original (right) and new (left) parts for the reel lock with large actuator knob

Original electric fence reel showing the lever that locks the line spool

A key ingredient is the added brake mechanism which comprises a printed part that pivots on a steel shaft that projects from the aluminium plate described earlier. An M3 brass threaded insert is heat-staked into the lever which enables a small leather pad to be attached with a screw and plate. These items can be seen in the photograph together with the brake handle. 

Parts for the brake handle and hold off lever

Parts for the brake handle and hold off lever

Brake handle, now replaced with smaller thumb button

Brake handle, now replaced with smaller thumb button

Friction brake

Friction brake

When winding in the line the reel lock is disengaged (by turning the black knob) and the friction brake held off with another small lever shown in the photographs. Finally, the line guide was assembled by gluing together the various components, and then mounting it on the projecting shaft that was previously bonded into the spindle. A serrated knob and wave washer are used to adjust the friction than holds the line guide at the desired angle.

Before any line was loaded onto the spool its effective diameter (originally 40mm) was enlarged by fixing twelve 6mm diameter bars between the flanges, increasing the diameter to 15cm. The end of the line is tethered to one of these cross-bars.

Hold off lever for the friction brake

Parts for the brake handle and hold off lever

Components for building the line guide

Components for building the line guide

One of the great strengths of combining solid modelling with 3D printing is that the technology brings freedom to your creative imagination. One example is the original design for the  brake handle which comprises a base cylinder with opposing tapered helices that are functional for grip and also attractive.  The latest version of the reel has a shorter thumb lever and a brass line guide to prevent erosion of the plastic end pieces.

Spare Voss spools are available, meaning that reels with different types of flying line can be exchanged. I usually fly with 100 pound Dacron but have another reel loaded with 200 pound Dacron for flying with kite stacks.

Brake handle, now replaced with smaller thumb button

Brake handle, now replaced with smaller thumb button