Some anadozing questions - Green?

[bbeishline]

Hi everybody,

This is my first post in this forum. I'm working on a framelock and have a few questions about anodizing titanium.

I am trying to get the colors teal and green and they just aren't coming up. I did a search on the web for general info and about all I got was something along the lines of, "Green is difficult to get on Ti, but easier on Niobium." Good to know but doesn't help me achieve the results I want! Green is toward the upper end voltage-wize, but when I go up there I don't get much color at all - mostly titanium color with a very slight green tint. For reference, the colors I am shooting for are like the Teal and Green Aqua from the second picture in this link:

http://www.titaniumfinishing.com/page09.htm

I have seen these colors on Ti before and was wondering if anyone knew specifically how to get them. I'm thinking that perhaps a big part of it has to do with surface preparation and acid etch before anodizing. Currently I finish to 1200 grit by hand and then anodize, and have no problem getting blues and purples that way. I have never tried an etch first. I've have seen it recommended, but never really knew exactly what it does. The info I have seen always says something like, "For the brightest colors, etch first." I've never seen anything that says, "Etching will help you get green" or something specific like that. Obviously if I had the materials I'd go ahead and try an etch to see what the result was, but since I don't I thought I'd check in here first and see what the deal is before I try to collect a bunch of hazardous chemicals.

What does everyone do for surface preperation before anodizing? That's something I haven't seen much info on. Can anyone help me out?

Thanks,

Ben

[Ray Rogers]

I etch my titanium before anodizing and I still can't get green. The etch is just to super clean the ti and make sure the surface is even and not splotchy. Like you, I've seen green but have no idea how to get it.

It's just a color on the spectrum and I occasionally see it but can't seem to 'settle' on it. But, even the green I have seen really wasn't all that great.

So, I don't think regular etching has anything to do with our lack of green but I sure would like for someone to tell me what does !

[Tom Anderson]

Pale green occurs at about 55 volts and teal green (aqua) occurs at about 105 volts (at least with my power supply.)

Bright (kelley) green (like true red) is impossible to get.

Be careful submerging thin parts at settings above 100VDC- they'll get scorched gray.

I wipe everything off with Windex immediately before immersing it in the electrolyte and wipe it off with Windex right after it comes back out.

[Don Cowles]

just an add-on; some makers are using nothing but Windex as the electrolite.

[A T Barr]

Originally posted by Tom Anderson
I wipe everything off with Windex immediately before immersing it in the electrolyte and wipe it off with Windex right after it comes back out.

Is there any advantages of using Windex instead of TSP? Do you use the Windex straight or diluted?

Thanks,

A.T.

"Don't you buy no ugly Knife"
My next show is the Knife Makers' Guild
Show July 11th-13th. I'm at table A-23.
Please come by and say hello.
http://www.customknives.com/

[Don Cowles]

Frank Dilluvio uses Windex straight from the bottle.

[Jette Bybjerg]

Hi Ben,

I remember seeing a thread by Kelly Carlson on anodizing titanium:

http://www.ckdforums.com/showthread....threadid=12095

Maybe this will help

Jette Bybjerg

[Tom Anderson]

Originally posted by A T Barr


Is there any advantages of using Windex instead of TSP? Do you use the Windex straight or diluted?

Thanks,

A.T.

I use Windex straight from the spray bottle. It helps eliminate fingerprints before going into the solution and removes any electrolyte residue after anodizing.

After applying the Windex, I dry the part with compressed air to make sure everything is clean.

[A T Barr]

Thanks for all of these replies.

A.T.

"Don't you buy no ugly Knife"
My next show is the Knife Makers' Guild
Show July 11th-13th. I'm at table A-23.
Please come by and say hello.
http://www.customknives.com/

[bbeishline]

Thanks to everyone for the info. The link to the other thread was quite a help. Before I read it I did try cranking my anodizer way up - it went to about 180V or so. I didn't get green but I did get pitting! I really need to get a test chunk of Ti to work on this...

Thanks again,

Ben

P.S. Everyone please overlook my typo in spelling "anodizing" in the original thread subject. I noticed it after my post and tried to edit it but I couldn't see a way to edit the actual title. Such a kind group here no one said anything, but I'm sure most noticed, as it looks pretty dorky.

[Jamey Saunders]

Originally posted by bbeishline
P.S. Everyone please overlook my typo in spelling "anodizing" in the original thread subject. I noticed it after my post and tried to edit it but I couldn't see a way to edit the actual title. Such a kind group here no one said anything, but I'm sure most noticed, as it looks pretty dorky.

I actually thought you had a seasick girlfriend named Anna who was taking a nap...

Oh, brother. I really need a vacation...

[Tom Anderson]

Here's a chart I developed a while back....

DC VOLTAGE: COLOR:

10.......... STRAW
15.......... DEEP GOLD
20.......... BRONZE
25.......... PURPLE
30.......... BRIGHT BLUE
35.......... SKY BLUE
40.......... POWDER BLUE
45.......... BLUE-WHITE
50.......... GREEN-WHITE
55.......... PALE GREEN
60.......... PALE YELLOW-GREEN
65.......... GREEN-YELLOW
70.......... GREEN-GOLD
75.......... COPPER
80.......... PINK
85.......... PINK-PURPLE
90.......... BRIGHT PURPLE
95.......... BLUE-PURPLE
100........ PURPLE-BLUE
105........ AQUA
110........ GREEN WITH RED MOTTLING
115........ GREEN WITH PURPLE MOTTLING
120........ BLUE WITH PURPLE MOTTLING
125........ MOTTLED PURPLE, GREEN, AND BLUE

There are a lot of color changes in between, but at least this will get you started!

[PeterAtwood]

I have a tough time getting green too. The best luck I've had has been on the edges if the edge is textured. And usually it shows up best when doing a spectrum/rainbow type of thing where you pull the piece from the solution while turning the power up. Also, I have noticed that sometimes reanodizing a piece will cause intensification of the edge colors. It is very tricky though, to get a grasp of what it is you've done so you can repeat it.

Reactive Metals has a non acid surface prep that is supposed to be helpful but I have not tried it.

Hey Tom, that power supply you sold me is still going strong. Thanks!

[Tom Anderson]

Originally posted by PeterAtwood
Hey Tom, that power supply you sold me is still going strong. Thanks!

Glad to hear that, Peter!

[Kelly Carlson]

To recap some earlier comments, I'm able to get nice bright greens at about 70 volts +/- , and brighter, but sometimes less even, at about 110 volts.
I've also got a 10 year old Walker with medium/dark green titanium scales. I don't know how he obtained med./dark green, as the closest I could get was at 190 volts, but with burn spots.
I do pre-etch in Reactive Metals etching solution, rinse the etch off in distilled water before anodizing, and use an electrolyte of a tablespoon of concentrated sulphuric acid to about a gallon of distilled water.
The color change is very fast in the 70 +/- volt range, so I start lower and slowly turn it up until I get the desire color.
Coop took many photos at the recent Stamford, CT, show, including one of my icicles with green liners - I'm not sure where, but do know its posted somewhere in this forum, and the green shown in the photo is an accurate color rendition. Looks very close to a "Kelly Green" to me.