How to Replace the Bands on the Neptonics Double Roller Speargun
There are many roller spearguns out on the market today. They all have their pores and cons. None of them have proven to be easy to re-power when the time has come to replace the bands on the speargun. The Neptonics Double Roller Speargun is not immune to these challenges. The benefits of being balanced and the amazing range of the speargun outweighs the drawbacks on this speargun. All the same, we have made this video and write up explain how to replace the bands on the Neptonics Double Roller Speargun.
Step One: Remove Double Roller Head Hardware
The first step in changing out the bands is to remove the double roller head hardware. This is done by removing the four retaining screws. Then you need pull the existing bands off the rollers that are on the non-welded side of the roller head. Once the bands are off that side you can pull off the roller wheels on that side. Use some force to pull the welded side of the roller head out from the speargun while the bands are still in place. You can keep the risers in place one the speargun, though they may want to come off. From there use a sharp pair of scissors to cut away the old bands.
Step Two: Tie Bands and Pull Them Through the Band Slot
One of the requirements to properly replace a Neptonics Double Roller’s Bands is to be able to tie your own bands. If you are not familiar with that process here is another blog post or video that demonstrates how to tie your bands. So you tie one side of your bands and you pull the bands through the existing band slot. Silicone Spray makes this process easier. Make sure the shorter band is in the band slot closest to the muzzle. For the 54 Double roller the band sizes are 44” and 48” bands for when you are cutting band material.
Step Three: Finish Tying the Bands
Once the bands are pulled through you need to finish tying the other side of the bands on the speargun. Make sure you tie the bands on the top side of the speargun. If you tie the bands on the bottom of the speargun you will have to stretch the bands over the top of the speargun, which is easier said than done.
Step Four: Hook The Wishbones on the Hardware and Replace the Roller Head
This is once again easier said than done. Take the welded side of the roller head with the roller wheels on the pegs. Place the band wishbones on the roller wheels in the correct order. The shorter band should in the further back of the two roller wheels. Use some leverage and put the welded pegs through the roller muzzle of the speargun. This should take some effort as the bands need to be pretensioned for the speargun to work properly. For a more detailed description of how double rollers work please read this blog post. Once you have the welded side of the roller place you should screw in the two retaining screws on the roller head.
Step Five: Put Rollers on and Pull Bands over the Risers
The next step is to replace the two roller wheels on the non-welded side of the roller head. From there you need to pull the bands over the risers and onto the matching roller wheel on the other side of the roller head. It is not overly complicated but does take some force. Once the bands are in place replace the remaining hardware and screw everything into place.
After that it just comes down to rigging the double roller, which is a different conversation.