The 'C' ring holding the helix in place has at times proved an issue removing it to continue a repair.

This tool has ben developed to simplify the process by including an internal full helix inside the main rod. I was able to include this feature as i have experience in making the replacement rods in durable materials.

By using this feature the broken rod is fully gripped right down to the C ring area so even the shortest remaining piece can be gripped.

The design also considers the effect of pulling the old part out by ensuring the cap is not put under stress as all the forces are directed in the correct direction avoiding twisting and leaving the space for the new C ring in tact. 

The helix inserted in the photo is for clarity and is not included in this sale.

Instructions :- I have included a video to help clarify how to use the tool as well as the description below.

Assemble the 3 parts of the tool push the slider as far as it will go to the end of its travel and screw the nut far enough on to leave a small gap between the sliding part. This will ensure the rod will be able to screw onto the helix to its maximum depth 

Screw the rod onto the broken helix as far as it will go without forcing it. The slider will stop you screwing on too far when the pen cap touches the edge of the slider when it reaches its stop. If the rod stops turning before the cap top touches the slider simply push the slider forward to close the gap (probably 1mm or less gap)

If the broken helix is bent you can use the metal fixing tool to straghten it prior to screwing the rod onto it

Grip either the slider or the flats area on the body and adjust the nut until it touched the back on the slider. At this point further tightening the screw will pull out the helix out of the cap and the whole tool is free to be removed along with the broken helix and the 'C' washer

The tool also includes the 'C' washer fixing tool which slides into the back end of the tool. The slider could be reversed to give a firm grip while the 'C' washer is inserted

You can see a demonstration of this tool by clicking on the link below (It Is Safe)

Demonstration of the Tool