I am doing A2 Level Product Design (as well as Physics obviously :tongue:) and I am making a workstand for a bicycle. It involves a ratchet and pawl mechanism which will be locked out by a solenoid acting on the pawl. The bike weighs roughly 12.1kg and the ratchet wheel from nylon. The pawl is aluminium and will be pushed into the ratchet by the slug protruding from the solenoid. I do not have any idea as to whether this solenoid will be strong enough, so please could someone let me know if it is? http://uk.rs-online.com/web/p/d-frame-solenoid/2500704/ If not, is there any particular size I should be looking for? Also, can anyone explain the difference between the difference between linear, rotary, tubular, c frame and d frame solenoids? One last question, how do I determine the current needed to lock the ratchet in place. If any of those questions could be answered I would greatly appreciate it. Many thanks, Dom.