degreaser question

[mkriegs]

I'm getting some wispy undyed streaks on my parts and I'm almost positive that it's from the degreasing step. One thing I've noticed is that my degreaser looks like it has a white slurry suspended in it. When I stir it the whole solution becomes white and when I let it sit the slurry settles to the bottom. So, my question is if that is normal or if that's an indication that my degreaser has gone bad?

And two more quick ones about glove cleanliness: should I worry about my gloves being dirty from touching my surroundings and affecting the part? And, can I touch the parts with gloved hands before the dying step or should I avoid that completely?

[acidrain]

The wispy areas are probably trapped acid. Are they near screw holes? Take care to squirt rinse water into all the nooks and screw holes after pulling from the ano tank.
Surface contamination doesn't usually do that. I'll bet your degreaser is fine.
As for the white slurry, mine does that as it get's cold, then disappears when heated, so I think it's normal.
If you can avoid touching the parts after ano (even with gloved hands) so much the safer. I usually keep the racking wires attached and just handle them that way until after sealing.

[mkriegs]

The wispy areas are pretty much scattered randomly around the parts and they almost look like an acid wash if that helps picture what I'm talking about. After the acid bath I usually spray down the parts well with distilled water in a garden spray bottle (the kind with the hand pump) and let them sit in a container of distilled water before going into dye. Also, if I rack with aluminum wire I use toothpicks and bamboo skewers wedged in a screw hole to help get a connection, but I worry about them absorbing acid during the anno process so I usually re-rack my parts before dye.

I'll see if I can get some pictures of my parts up.

[acidrain]

Another reason Ti wire works so good.
Try to get some pics up. Could it be little spots of buffing compound? Those will hold acid too.

[mkriegs]

Grr, this is my third run in a row at %100 part failure rate.

It was almost impossible to get an angle where you could see the flaws past the glare off of the gloss finish but here it is:

http://i204.photobucket.com/albums/b...7/P4090031.jpg

http://i204.photobucket.com/albums/b...7/P4090028.jpg

I'm pretty much convinced that this is due to improper rinse after the acid bath just like you said. I literally just realized that I've gotten kind of cheap/lazy and haven't been soaking the parts in distilled water in addition to spraying. Instead I've just been spraying them twice as hard with a garden sprayer full of DW thinking it would be good enough.

I really need to start making an etched-in-stone checklist of my process to avoid this sort of thing.

[acidrain]

Yeah, I think you've answered your own question... looks like acid dragover to me.
Try this: Pull the parts and spray rinse them into your ano tank, then hang in them in a clean rinse tank.
Then, when going to the dye tank, rinse again into the rinse tank.
Ano, spray, dunk, spray, dye works for me.

[destroyer125]

A rinse tank is a good way to combat what a spray doesnt get off. Industrial places use something called a cascade rinse system to wash their parts off. Which is a double sided tank, water enters one side from the bottom, flows upward, and overflows into the other side then to the wastewater system. All the chemicals wash upward and over into the other tank, completely washing the parts.

[mkriegs]

I started using a rinse tank and my results are significantly better although I'm still having some (but not as much) trouble with the eye covers, even though they're probably the last part you would expect to hold acid .

[mkriegs]

hey, just one more question. Is it possible that the turquoise dye has in some way gone bad and is partially what is causing these marks?

I have two pairs of these same eye covers that I'm doing (one pink, one turquoise) and the pink ones came out fine on my very first try whereas these turquoise ones are still giving me problems. I've been doing them in the same run using the same exact procedure and still the turquoise ones give me "acid dragout-like" blemishes.

[destroyer125]

I have that problem with alot of light colors, IE Turqoise, Teal, etc. Ive found heat and agitation in the dyes prevent that. To agitate 5 gallon buckets, buy the little $5 hobby fountain sumps from harbor freight and just throw them down in the tank. Wash them first though and when you switch dyes.