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SPEARBANDS.COM • BAND BUILDER V2

Speargun Band Calculator

Built around rubber type, band diameter, band count and shaft mass — not shaft diameter alone.

Conventional circular bands

1. Gun & shaft

2. Rubber setup

3. Band construction

Factory-informed starting points include RIFFE technical setups, Rob Allen factory band/shaft pairings, Pathos TNT elongation guidance, and MAKO/Primeline published stretch recommendations. Use manufacturer-specific guidance when it is known.
------- Speargun Band Length Calculator V.1
🌊 Band Builder

Speargun Band Calculator

Measure from the band slot to the shark fin, choose your setup, and get a practical rubber cut length in seconds.

1 Enter your measurements

?
?
in
?
in
?
in
Loading preference
Rubber stretch
Adjust this for your rubber and preferred loading effort.
300%
Easy Balanced Powerful

2 Your band length

Cut each rubber band to
28.25 inches
Approximately 71.8 centimeters per band
Suggested preset
300%
Total rubber needed
84.75 in
Loaded rubber path
85 in
Stretch multiplier
3.00×
Formula used ((2 × slot-to-fin distance) − wishbone) ÷ stretch multiplier + allowance
💡
Shaft diameter does not directly change the geometry. It helps choose a sensible starting stretch setting. Rubber diameter, rubber formulation, shaft length, band count and gun stiffness also affect the ideal setup.

Designed for conventional circular speargun bands. Roller and inverted-roller guns require a different calculation.

SPEARBANDS.COM • BAND BUILDER V2

Speargun Band Calculator

Built around rubber type, band diameter, band count and shaft mass — not shaft diameter alone.

Conventional circular bands

1. Gun & shaft

2. Rubber setup

3. Band construction

Factory-informed starting points include RIFFE technical setups, Rob Allen factory band/shaft pairings, Pathos TNT elongation guidance, and MAKO/Primeline published stretch recommendations. Use manufacturer-specific guidance when it is known.
------- Speargun Band Length Calculator V.1
🌊 Band Builder

Speargun Band Calculator

Measure from the band slot to the shark fin, choose your setup, and get a practical rubber cut length in seconds.

1 Enter your measurements

?
?
in
?
in
?
in
Loading preference
Rubber stretch
Adjust this for your rubber and preferred loading effort.
300%
Easy Balanced Powerful

2 Your band length

Cut each rubber band to
28.25 inches
Approximately 71.8 centimeters per band
Suggested preset
300%
Total rubber needed
84.75 in
Loaded rubber path
85 in
Stretch multiplier
3.00×
Formula used ((2 × slot-to-fin distance) − wishbone) ÷ stretch multiplier + allowance
💡
Shaft diameter does not directly change the geometry. It helps choose a sensible starting stretch setting. Rubber diameter, rubber formulation, shaft length, band count and gun stiffness also affect the ideal setup.

Designed for conventional circular speargun bands. Roller and inverted-roller guns require a different calculation.

SPEARBANDS.COM • BAND BUILDER V2

Speargun Band Calculator

Built around rubber type, band diameter, band count and shaft mass — not shaft diameter alone.

Conventional circular bands

1. Gun & shaft

2. Rubber setup

3. Band construction

Factory-informed starting points include RIFFE technical setups, Rob Allen factory band/shaft pairings, Pathos TNT elongation guidance, and MAKO/Primeline published stretch recommendations. Use manufacturer-specific guidance when it is known.
------- Speargun Band Length Calculator V.1
🌊 Band Builder

Speargun Band Calculator

Measure from the band slot to the shark fin, choose your setup, and get a practical rubber cut length in seconds.

1 Enter your measurements

?
?
in
?
in
?
in
Loading preference
Rubber stretch
Adjust this for your rubber and preferred loading effort.
300%
Easy Balanced Powerful

2 Your band length

Cut each rubber band to
28.25 inches
Approximately 71.8 centimeters per band
Suggested preset
300%
Total rubber needed
84.75 in
Loaded rubber path
85 in
Stretch multiplier
3.00×
Formula used ((2 × slot-to-fin distance) − wishbone) ÷ stretch multiplier + allowance
💡
Shaft diameter does not directly change the geometry. It helps choose a sensible starting stretch setting. Rubber diameter, rubber formulation, shaft length, band count and gun stiffness also affect the ideal setup.

Designed for conventional circular speargun bands. Roller and inverted-roller guns require a different calculation.

Enhanced accuracy

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Bestseller
Example product
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Example product

Example product

$100.00
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SPEARBANDS.COM • BAND BUILDER V2

Speargun Band Calculator

Built around rubber type, band diameter, band count and shaft mass — not shaft diameter alone.

Conventional circular bands

1. Gun & shaft

2. Rubber setup

3. Band construction

Factory-informed starting points include RIFFE technical setups, Rob Allen factory band/shaft pairings, Pathos TNT elongation guidance, and MAKO/Primeline published stretch recommendations. Use manufacturer-specific guidance when it is known.
------- Speargun Band Length Calculator V.1
🌊 Band Builder

Speargun Band Calculator

Measure from the band slot to the shark fin, choose your setup, and get a practical rubber cut length in seconds.

1 Enter your measurements

?
?
in
?
in
?
in
Loading preference
Rubber stretch
Adjust this for your rubber and preferred loading effort.
300%
Easy Balanced Powerful

2 Your band length

Cut each rubber band to
28.25 inches
Approximately 71.8 centimeters per band
Suggested preset
300%
Total rubber needed
84.75 in
Loaded rubber path
85 in
Stretch multiplier
3.00×
Formula used ((2 × slot-to-fin distance) − wishbone) ÷ stretch multiplier + allowance
💡
Shaft diameter does not directly change the geometry. It helps choose a sensible starting stretch setting. Rubber diameter, rubber formulation, shaft length, band count and gun stiffness also affect the ideal setup.

Designed for conventional circular speargun bands. Roller and inverted-roller guns require a different calculation.

We champion authenticity and precision in every aspect of spearfishing.

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