Thought I would share this with the gang: Our above cited friend PM'd me a while back. "Oh No!", he sobbed... "I took my spheres to a LDS for a visual, and they told me that they are rusty inside!" <insert gnashing of teeth and wailing here>.... "They would tumble them but they don't have a tumbler that will work on them"... <moan......>....
"Settle down", says I. "Send 'em to the LDSOH and I'll look them over" (and make DIN valves for them at the same time).
(naah, it wasn't *really* like that, I just enjoy a good sea-story. But you get the point)...
So.... they came last week. Today I stuck a borescope down their skinny necks and guess what? They are *immaculate* inside. Like new. Perfect. Clean as a whistle. The deal is that the teflon coated (white) spheres are parkerized before being coated on the exterior. The parkerizing is a black/grey phosphate treatment that is very corrosion resistant. Apparently the LDS has only ever seen bright galvanized cylinders shining brightly in the glare of their inspection light, and mistook the parkerized finish for rust (fools). If they had done what they wanted to, they would have (A) removed the parkerizing by tumbling, and (B) beat the crap outta the teflon on the outside while doing so. Likely they would have ruined them.
Lesson learned: NEVER take your spheres to a LDS and leave them.... it's not gonna come out well for you, trust me on this.
Photo shows the 2 spheres in their (immaculate interior) spendor, newly fitted with Draeger 200 BAR DIN pillar valves. These valves start out as tapered kleinkonish (German tapered thread) valves, and after a little turning in the lathe (there's barely enougnb extra meat, but there's enough) and rethreading (5/8-18 TPI), they make nice DIN valves for the Mark-15's. Color coded tape, new ANDI cylinder contents gauges, and they are on their way back to Texas.
Another good day at the LDSOH.
Dave
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