illusion wrote:you broke three keys?![]()
you are definately hitting them too hard in this case...
have you seen the videos I posted recently regarding bumping?
I have found that whilst it relies on some luck to a certain extent 10 strikes or less are are usualy all that's needed to bump the lock.
I can bump the lock 1 out of 3 times as long as it is in my hands and I turn it clockwise

I watched the videos after I read your post and it really helped. Now I'm hitting more mildly. Although it seemed impossible to bump with such a small force, actually it is easier.
I concluded that the reason is the roughly cut keys. Because more than unsuccesful hits, I usually end up with a half turned key. Some of the pins easily set but the others stops the lock.
Today I will try to get a proffessionally cut key set from a locksmith. I will tell him that I'm planning to use the keys on a project at the university. I hope he will believe me after seeing my ID card as an assitant at the faculty of mechanical engineering

Regards...