Tamron 17-50 non VC aperture problem

Hi. I use cheap macro tubes and make the DoF bigger, I pre-set the aperture of the lens beforehand.
1) use lens on body
2) set to Av or M
3) use f/5.6 or smaller
4) while pressing DoF preview button
5) release lens -
6) put macro tubes & lens
After taking shot i put lens back to the body and set it off. Aperture return to default position but when i turn camera on aperture move a little and error 99 appear. So i disassembled lens, moved with lever connect to aperture and can shut her just to 50%

Ok, so you broke your lens. Sell it for parts, and buy a new one. And if you want more depth of field for macro, get an old manual focus M42 macro lens, or something like a Tamron 90mm for about $300US.

Auto ext. tubes do not cost a lot.