Airsoft Canada - View Single Post - Piston locked back on a Scar Gearbox, Hopefully Urgent Help Please. Thanks =)

gerardcb · August 31st, 2010, 01:59

Hi guys!! I upgraded a DBoys Scar.

I tried to fire the gun and the piston locked back and got stuck in the back.

Upgrades put in the gearbox:

- Matrix High Performance Magnum Airsoft AEG Motor - Long Type

- "Matrix" Steel CNC "Low Noise" Airsoft AEG Gear Set (High Torque) / 100:300

- Matrix Full Steel Teeth Polycarbonate Piston w/ for Airsoft AEG Gearbox

- Matrix Element Silent Piston & Cylinder Set for V.2 Gearbox.

- Matrix Element Ball Bearing Vortex Spring Guide for V.2 Airsoft AEG Gearbox

- Matrix PDI Type 260% / M130 Irregular Pitch Airsoft AEG Upgrade Spring (450~520 FPS)

Problem: I fired the gun and the piston got stuck in the back and did not release.

Suspects:

- Motor Plate Screw does not tighten, therefore motor plate is a little bit loose. Just a little.

- Shimming? I took so much time and effort to shim it. But it has diagonal teeth on the gears so I believe that requires a much more precise tuning?

- I did not have silicon oil present, so I used silicon oil Gear lubricant in the places where normal silicon oil is needed.

- Battery. I used an 8.4v mini for the first trigger pull. That probably is the cause of the piston locking back, but even with a 10.8v, it did not unlock.

Any other ideas?

Thanks!!!!!

August 31st, 2010, 01:59	#1
gerardcb Trader rating Join Date: Mar 2009	Piston locked back on a Scar Gearbox, Hopefully Urgent Help Please. Thanks =) Hi guys!! I upgraded a DBoys Scar. I tried to fire the gun and the piston locked back and got stuck in the back. Upgrades put in the gearbox: - Matrix High Performance Magnum Airsoft AEG Motor - Long Type - "Matrix" Steel CNC "Low Noise" Airsoft AEG Gear Set (High Torque) / 100:300 - Matrix Full Steel Teeth Polycarbonate Piston w/ for Airsoft AEG Gearbox - Matrix Element Silent Piston & Cylinder Set for V.2 Gearbox. - Matrix Element Ball Bearing Vortex Spring Guide for V.2 Airsoft AEG Gearbox - Matrix PDI Type 260% / M130 Irregular Pitch Airsoft AEG Upgrade Spring (450~520 FPS) Problem: I fired the gun and the piston got stuck in the back and did not release. Suspects: - Motor Plate Screw does not tighten, therefore motor plate is a little bit loose. Just a little. - Shimming? I took so much time and effort to shim it. But it has diagonal teeth on the gears so I believe that requires a much more precise tuning? - I did not have silicon oil present, so I used silicon oil Gear lubricant in the places where normal silicon oil is needed. - Battery. I used an 8.4v mini for the first trigger pull. That probably is the cause of the piston locking back, but even with a 10.8v, it did not unlock. Any other ideas? Thanks!!!!!