- 3D Printer
- Screwdriver
- Pliers
- metal saw
- drill with 4mm and 5mm drill bit
- flat metal file
- instant glue
- 100g Filament for your 3D Printer
- 1 4mm x 400mm metal rod
- 1 paper charging roller for printers: like https://www.aliexpress.com/item/4001350443434.html
- 2 springs 30mm x 5mm: like https://www.aliexpress.com/item/1005005312536098.html?spm=a2g0o.order_list.order_list_main.101.13c6194def1vQR
- 1 geared dc motor JGA25-370 12V, 1:60 gear ratio: like https://www.aliexpress.com/item/1005004762042393.html
- 1 roll of target witness paper: like https://www.amazon.in/Black-Paper-Electronic-Scoring-Target/dp/B0BWFJ9MSM
- 2 M5 20mm nuts and bolts for the paper charger
- 2 M3 6mm bolts for the engine to holder frame
- 10 wood screws to attach the paper holder and paper pull
Print the 3d parts tbd add links to 3d model for each:
- roll holder frame and roll paperrollholder00.stl
- two pairs paper guide rod holders witnesspaperguide00.stl
- paper pull frame paperpullmount02.stl
- motor holder frame motormountJGA2500.stl
- motor coupler coupler00.stl
All the 3d models are in this file: witnesspapersetup-allparts.3mf
Cut the 4mm rods like this: One piece of 120mm and two of 110mm length.
Paper roll holder: Attach the roll holder above the target to the target box with 4 wood screws. Put the 120mm rod into the rollholder roll. Put the witness paper roll on the rollholder.
Paper guide rods: Attach the 3d printer paper guide rod holder to the two 110mm rods and glue the paper guide rod holder to the FreETarget sensor frame.
Paper pull frame: Cut the paper charging roller for printers in the middle.
Remove the rubber on the side where you cut it, so that the rubber that remains is 90mm wide. Remove the residue of the glue and rubber: I attached my paper charing roller into my drill and used sand paper to evenly remove the residue.
Put the spring into the hole on the top.
Push the M5 nut in the hole on the top using a plier.
Put the other paper charging roller into the upper hole of the paper pull frame by pushing the spring up, to push the paper charging roller into its hole.
Screw in the M5 spring tension.
Screw the motor with the M3 screws to the motor holder frame.
File a segment of the paper charging roller until it fits the motor coupler on its end.
Put the coupler on the motor and the paper charging roller on its other side.
Put the motor paper roll charger into the hole of the paper pull frame.
Attach the paper pull frame and the motor frame on the target box.
Find a simple way to attach the rod for the roll holder, so it can't slip out. Glueing is not a good option as it adds friction. Maybe a cap that is slightly conic inside, so the rod doesn't move out.