Động cơ gắn họp số tỉ lệ từ khoảng 1/30 - 1/50 là ok.

It depends on the builder. I can already build most of this for next to nothing since I already own steel tubing and a stirrup pump. The only kicker would be the motor, but ebay should make that very cost effective. If you needed to purchase materials, I would guess at about £100 to get a working rig, including materials for the frame, the pump and motor

@@GaisaSanktejo Yes makes so much sense now. Thanks clarifying.

@@la2123 No problem. To be honest, I looked into this myself because one of my airguns has a 500cc tank and using a stirrup pump to fill THAT is a killer! LOL I'm currently trying to find out what motor they used but if its beyond my price range, a windscreen wiper motor could suffice (Others have used such)

@@GaisaSanktejo Yes building a machine to do the job of 400 or even 500 strokes of manual pumping is definitely a great helper. But you may need to service frequently. Plus, it's not as noisy as a compressor. It's well executed i must say.

@@la2123 I can live with frequent servicing and using plenty of silicone lube. Much more so than using the pump manually... and as for 4-500 strokes? I'd be more inclined to say about 1000