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HopChop Mk4 Guide - R-Hop Cutting Jig 3d printed

Not a Photo

White Acrylic
HopChop Mk4 Guide - R-Hop Cutting Jig 3d printed
HopChop Mk4 Guide - R-Hop Cutting Jig 3d printed

Not a Photo

HopChop Mk4 Guide - R-Hop Cutting Jig

  • 3D printed in White Acrylic: Firm white plastic with a smooth surface and rubbery feel.
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  • This product is intended for mature audiences.
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Product Description

Choose the right size guide for your tubing:
Small = 8 mm
Medium = 9 mm
Large = 10 mm
X-Large = 11 mm 

The is one half of the HopChop cutting jig. When paired with a HopChop Blade Fixture, the HopChop provides infinite adjustment in the cutting depth of the silicone tubing used to make R-Hop patches. R-Hop is an accepted method in the airsoft community to apply a consistant and tunable backspin on the BB pellet. Check out the AirsoftMechanics forum for more details about R-Hop.

The job of the feed guide is:
  1. provide a variable cut depth as the guide is rotated
  2. provide a smooth path for the tubing as it is cut
This Mk4 guide is backwards compatible with previous HopChop jigs and adds a new o-ring groove that improves the centering between the guide and the blade fixture and also keeps the guide from spinning during a cut. The groove is designed for a 1.5mm x 21 mm o-ring which is the same o-ring used in AEG cylinder heads so any spare parts bin should have one. Also available from McMaster Carr.

This feed guide is designed for silicone tubing with an inside diameter (ID) of 6 mm. The tubing can be sourced from McMaster-Carr:
8 mm: 5041k693

9 mm: 5054k24
10 mm: 5041k744

This feed guide has a scale between 0 and 3 mm in 0.2 mm increments and correspond to the inside diameter of the tubing. To change the cut depth, the feed guide is rotated clockwise until the desired depth mark lines up with the origin mark of the blade fixture. Then insert the tubing through the feed hole and run through the blade until the desired length is achieved. Remove the tubing by pulling it out of the feed hole and then cut the patch off the tubing using another sharp blade.

Due to the nature of the material, it is recommended that the feed hole be given a light sanding to provide a smooth feed. This can be done with 800 grit or greater sand paper rolled up to fit into the feed hole. It is also recommended to lightly oil the cutting blade and tubing exterior with silicone oil prior to each cut.

Find more at the Spin Rate Engineering website.
What's in the Box
HopChop Mk4 8mm
White Acrylic
3.5 cm
3.8 cm
1.5 cm

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