Thx Steve and Henry, the model will be around 500lbs when ready, yes it´s a big model, the blade cylinders are 1 fot long!
Have finaly got the track recoil finalized, have new 55mm (~2") diameter steel tubes done that will be cromed, have a brass bushing on the rear inside tube, a delrin bushing in front with a seal. The spring function will be a lockable gas spring inside tube (that´s an old used one in pic). They are activated with the small pin in the left end and can be ordered with various force. I´m planning for a 40kg/88lbs setting that can be reduced if needed.
Activation on the spring will be thru the normal hole where you put in grease in the recoil cylinder when it´s a 1:1 machine. The working stroke will be around 1", that´s enough with my chain pitch.
Dan