[kmurphy220]

Just a few hours ago I was sitting around bored and I thought about how my macro filters really were a major pain in the A$% so I thought that I would buy tubes. After reading how the cheap off brand tubes ruined some guys lens I figured I would make my own. So I took an old Rokunar TC and stripped out the mount. Attempted to get the glass off but ended up bending the mount. Thankfully my lens obsession left me with a few mounts laying around and I sanded down the Rokunar and attached a new smaller mount for a pretty nifty tube for my 50 1.7

[UncleVanya]

Neat. I personally use M42 extension tubes with an Enlarging lens when I want to use tubes. I also have a pristine M42 Bellows for the same purpose. The bellows needs a little extension tube to get it out away from the overhanging pentaprism but otherwise works great.
Check this thread out to see my extension tubes in action: https://www.pentaxforums.com/forums/177-macro-photography/285041-lightweight-macro.html