Project Scope: Variable-Speed Rotary Flag-Pulling Trainer
Budget: $250 – $750 USD
I need a rotating wheel mounted on a center-column. I have 8 plastic flag sockets that need to be bolted to the edge of the wheel. The whole thing needs to spin at variable speeds and move up and down about 5 inches while it's turning."
1. Project Overview
Construction of a floor-mounted training device for flag football. The machine features a rotating horizontal wheel (waist-high) that holds multiple flag "poppers." The device requires two simultaneous motions: continuous rotation and vertical oscillation (bobbing up and down).
2. Technical Specifications
* Target Height: Fixed at 30–36 inches (waist-high).
* Rotational Motion:
* Variable speed control (approx. 0–60 RPM).
* Drive must handle 5 distinct speed presets.
* Vertical Motion (Oscillation):
* The wheel assembly must rise and fall 4–6 inches during rotation.
* Mechanism: Cylindrical cam or mechanical linkage.
* Flag Interface (The "Gauntlet"):
* Wheel Size: 24-inch to 30-inch diameter.
* Mounting Points: 6 to 8 flag sockets mounted at equal intervals around the perimeter.
* Hardware Compatibility: Designed for "Sonic Pop" style female sockets (standard vacuum-seal flag connectors).
3. Component & Hardware Details
* Mounting the Poppers: The "Sonic Pop" female sockets usually come with a small plastic "stem" designed for a belt. For this machine, the builder will need to either:
* Direct Bolt: Drill a hole through the wheel and use a bolt/washer through the back of the socket.
* Bracket Mount: Use small "L" brackets to keep the sockets facing outward horizontally.
* Drive System: High-torque 12V/24V DC Gearmotor. Note: Increasing to 8 flags adds weight and pull-drag; a motor with at least 80 kg-cm of torque is recommended.
* Safety: The wheel must be "soft-edged" (padded with foam) to prevent injury if the athlete's hand misses the flag and strikes the rotating wheel.
You should use a "Shaft-within-a-Sleeve" design. This allows the inner part to spin and move up and down, while the outer part remains rock-solid.
The Recommended Materials
1. The Outer Support Column (The "Stationary" Part)
• Material: Schedule 40 Steel Pipe (1.5" to 2" diameter).
• Why: You can buy this at any Home Depot or Lowe's. It is incredibly rigid and can be welded easily to a heavy base plate. Steel is much better than PVC here; PVC will "whip" or flex when the flags are pulled, which could cause the motor to bind or the belt to slip.
2. The Inner Rotating Shaft (The "Moving" Part)
• Material: 304 Stainless Steel Precision Ground Shafting (5/8" or 3/4" diameter).
• Why: You want "precision ground" steel because it is perfectly round and smooth. This is important because it needs to slide up and down through bearings or bushings without friction. Stainless steel won't rust if you leave the machine in the garage or a damp equipment shed.
• Where to get it: McMaster-Carr (Search: "Rotary Shafting").
How the Assembly Works
To get that "bobbing" motion you want, the setup looks like this from the inside out:
1. The Outer Pipe stays still and is bolted to the floor/base.
2. Linear/Rotary Bushings are pressed into the top and bottom of the outer pipe. These are special bearings that allow the inner shaft to both spin and slide up and down at the same time.
3. The Inner Shaft sits inside those bushings.
4. The "Wave" Cam is a piece of metal shaped like a roller coaster track welded to the top of the outer pipe.
5. The Follower is a small peg or roller attached to the inner shaft. As the motor spins the shaft, the peg hits the "wave" and forces the whole shaft to lift.
1. Project Overview
Construction of a floor-mounted training device for flag football. The machine features a rotating horizontal wheel (waist-high) that holds multiple flag "poppers." The device requires two simultaneous motions: continuous rotation and vertical oscillation (bobbing up and down).
2. Technical Specifications
* Target Height: Fixed at 30–36 inches (waist-high).
* Rotational Motion:
* Variable speed control (approx. 0–60 RPM).
* Drive must handle 5 distinct speed presets.
* Vertical Motion (Oscillation):
* The wheel assembly must rise and fall 4–6 inches during rotation.
* Mechanism: Cylindrical cam or mechanical linkage.
* Flag Interface (The "Gauntlet"):
* Wheel Size: 24-inch to 30-inch diameter.
* Mounting Points: 6 to 8 flag sockets mounted at equal intervals around the perimeter.
* Hardware Compatibility: Designed for "Sonic Pop" style female sockets (standard vacuum-seal flag connectors).
3. Component & Hardware Details
* Mounting the Poppers: The "Sonic Pop" female sockets usually come with a small plastic "stem" designed for a belt. For this machine, the builder will need to either:
* Direct Bolt: Drill a hole through the wheel and use a bolt/washer through the back of the socket.
* Bracket Mount: Use small "L" brackets to keep the sockets facing outward horizontally.
* Drive System: High-torque 12V/24V DC Gearmotor. Note: Increasing to 8 flags adds weight and pull-drag; a motor with at least 80 kg-cm of torque is recommended.
* Safety: The wheel must be "soft-edged" (padded with foam) to prevent injury if the athlete's hand misses the flag and strikes the rotating wheel.
You should use a "Shaft-within-a-Sleeve" design. This allows the inner part to spin and move up and down, while the outer part remains rock-solid.
The Recommended Materials
1. The Outer Support Column (The "Stationary" Part)
• Material: Schedule 40 Steel Pipe (1.5" to 2" diameter).
• Why: You can buy this at any Home Depot or Lowe's. It is incredibly rigid and can be welded easily to a heavy base plate. Steel is much better than PVC here; PVC will "whip" or flex when the flags are pulled, which could cause the motor to bind or the belt to slip.
2. The Inner Rotating Shaft (The "Moving" Part)
• Material: 304 Stainless Steel Precision Ground Shafting (5/8" or 3/4" diameter).
• Why: You want "precision ground" steel because it is perfectly round and smooth. This is important because it needs to slide up and down through bearings or bushings without friction. Stainless steel won't rust if you leave the machine in the garage or a damp equipment shed.
• Where to get it: McMaster-Carr (Search: "Rotary Shafting").
How the Assembly Works
To get that "bobbing" motion you want, the setup looks like this from the inside out:
1. The Outer Pipe stays still and is bolted to the floor/base.
2. Linear/Rotary Bushings are pressed into the top and bottom of the outer pipe. These are special bearings that allow the inner shaft to both spin and slide up and down at the same time.
3. The Inner Shaft sits inside those bushings.
4. The "Wave" Cam is a piece of metal shaped like a roller coaster track welded to the top of the outer pipe.
5. The Follower is a small peg or roller attached to the inner shaft. As the motor spins the shaft, the peg hits the "wave" and forces the whole shaft to lift.