Etching different steels question

[dbalfa]

I've got an irritating etching issue (say that fast three times ) When I electrically etch my blades, I get inconsistent results even though I have gotten very specific to do the same things every time. Attached is a photo of the last three I've done. The top two are 01, the bottom is 440C. The 440C, and ATS-34, Ive used all etch outstandingly, beautiful, crisp, dark etch that stays with it. I have had only a fraction of the 01 blades turn out that well. They all etch, but some loose the darkening, some get a little hazy, many, like the middle blade, are crisp lines but "gravely" inside and won't take darkening. I am using the etchant that IMG sent me that is supposed to be for blade steels. At the time, I told them I was only using carbon steel/alloys but it seems to work better on SS???

Here is my basic procedure- clean the blade with acetone/MEK, lay the stencil on with a dampening of moisture to help hold it in place, dampen the pad with etchant, do three cycles of 4 secs of each polarity, wash the blade off, polish the area with wet 2000 grit to crisp the edges. Sometimes the magic works, sometimes it don't...

Any suggestions?

[TJ Smith]

I use scotch tape to hold stencil in place. It looks like your pad may have to much etchant in it . To wet. It's a fine line between to wet and not wet enough.
I've seen a couple threads on using q-tips instead of the pad. This should eliminat the to wet problem and clouding of the etch.
If you see fluid wicking out to the edge of your stencil you will get some clouding.
My .02$
Take Care
TJ

[Ray Rogers]

I'm with TJ on that, use Scotch tape to hold the stencil to the blade and don't put anything wet under the stencil. The wet solution that passes through the clear parts of the stencil conduct electricity to the steel causing the etch. If the entire underside of the stencil is wet you may be 'shorting' the etch and running it to places it shouldn't go.

Also, there are solutions especially for stainless steel and another for carbon steel as well as for other materials. They all will work more or less on anything but they generally work best as advertised. I don't think this is really important to your current problem though ...

[dbalfa]

How would you use a Q-tip instead of the pad? I'm thinking your using the Q-tip to apply etchant instead of applying it to the pad??? I usually apply etchant to pad, then dab it onto a paper towel. I will try less juice....

Has anyone tried varrying "weights" of felt for the pad with any success? My cheap felt seems like it may be to course or loose woven. Could that contribute?

[Ray Rogers]

The felt is there to hold enough liquid to complete the electrical circuit, more than that is not needed. Your circuit is being completed so your felt seems OK so far. Too much liquid, especially under the stencil, is the likely source of your problem ...

[Scott Davidson]

Originally Posted by Ray Rogers

The felt is there to hold enough liquid to complete the electrical circuit, more than that is not needed. Your circuit is being completed so your felt seems OK so far. Too much liquid, especially under the stencil, is the likely source of your problem ...

I agree with Ray , in times before when i have had to much liquid , if it gets " too wet " under the stencil , it will cause a bad transfer to your blade . I am using the thin felt from wally world , its cheep enough to use one time on 4-5 blades and then throw it away . Just my $ .02 worth . SCOTT

[dbalfa]

Thanks gentlemen...I guess I'll quit licking my stencils They don't taste too good anyway. I have noticed some bubbling from time to time, according to your replys, that would clearly indicate too much etchant. Maybe I'll try a more precise measurement like a dropper instead of the squirt and squeeze technique.

I have also noticed a couple of the stencils look to have "burned through" in a couple places. I suppose they should be discarded? They still give a good etch but may be allowing some etchant through to the underside, which may not be good.

[Ray Rogers]

If the burned stencils allow etchant to pass through you will not have any trouble knowing about it since there will be a black mark on your blade at that spot.

I forgot to mention that the etch times are not necessarily the same for carbon steels and stainless steels. With my set up, I find that carbon steels etch noticeably faster than stainless steels so I shorten the etch times on carbon. Etch time should be in the 20 to 25 second range. The etching pad should be applied in 5 second cycles with 3 seconds on the stencil followed by 2 seconds off. Not doing it this way will likely result in burned stencils and blurry etches ...