Staff note: This post may contain affiliate links, which means Pentax Forums may earn a small commission if a visitor clicks through and makes a purchase. If you would like to support the forum directly, you may also make a donation here.
I bought an “experienced” SMC-A 24-50mm f4 on ebay for $42 total, delivered to me.The lens had multiple deep dents in its front filter ring, bad enough that even a lens cap wouldn’t mount. Optically, it has the fine dust inside typical of a much used 1980’s lens, but no fungus, oil or mechanical issues.
My filter ring repair spanner has been used to massage some fairly significant dents out filter rings, but never several spread across the threads. Surprisingly, in less than half an hour of work, I was able to carefully, fully mount and remove filters and lens hoods. This one repair is worth the price of the tool.
The trick is, put the tool threads on the side opposite the damage deep, as close to bottoming out as possible. Put the tool threads high, at near the top of the damage then slowly turn the screw to add pressure. Work the tool further down as the threads resume shape. Keep repeating for each dented area. When it looks good, loosen the tool enough to screw it into the threads lightly, then screw then lens in and out slowly feeling for binding. Tight areas need a bit more massaging with the tool. Check your work with a good quality, metal ring filter or lens hood.
*** I have since done some limited test shots with this lens and the results are very good. No lasting effects other than cosmetic.****
Last edited by steamloco76; 02-22-2021 at 02:42 PM.