Electro-Etching problems, need advice

D

Dixieblade57

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Jun 20, 2007
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This is kind of lengthy but will try to get to point a quickly as possible! I built a unit of this tutorial http://www.chriscrawfordknives.com/cck/Etcher_Tutorial/Default.asp or I should say my son in law did. The one thing he changed is he put in a larger transformer they had laying around in there scrap bin at work. At least I think thats what he told me I can't reach him today. This may be my problem as someone pointed out before. So there is one thing I need to look at!
I have ordered some stencils and thought I would get in a little practice before they get here. My next problem may be my etchant solution. When I posed this question before I got all sort or answers. This is what I mixed up, 1cup of white vinegar, 4lbs. of Morton Pool Salt, to 1gal. of water. It is heavy on the salt in the mix.
My next problem not having a stencil I tried to resort to another solution. I sanded my metal down to 1200 grit to be stenciled, cleaned it with acetone and put on a heavy coat of finger nail polish, thanks to the wife.
When dry I scratched off where I wanted my design. The first try I went on DC for 30 seconds and AC for 30 seconds. It eat the fingernail polish slap off the metal.:eek:
Now the felt is plugged up with the fingernail polish. Decided to try round two anyway without changing the felt! I went to second attempt and went on DC for 1 1/2 min. and AC for 2 min. This worked best. I got a fair mark but it seems to be raised above the metal, I can feel it with my finger. Is that normal? If I try to buff it up its going to take the raised area off and then I won't have anything left!:(
I went to the third try and still not changing the ever increasingly plugged up piece of felt and went 2 min. DC and 2 1/2AC. I lost alot of the finger nail polish again and only about 1/2 of the design printed and the rest of the finger nail polish raised again on the other half. It did not print as good as try #2.:rolleyes:
OK so what's the problem, the transformer?
The finger nail polish?
My solution?
My time on the metal?
Any suggestions are appreciated as these results sucked, big time!:jerkit:
 
I just started etching myself and And i havent had the prob your having. MIX- 1cup h2o/ 1cup-white vinegar/ And 1/3cup sea salt. I run a 1a out put converter with gator clips. Clip the positive to the blade and dip a Q-tip in the shaken solution and clip the negitive gator clip to the wet end of it. Just run it across you cut out. Hope this helps you-JOSH Go look at the cherry burl knife thats posted in the fixed blades, and the first order out in the custom gallery
 
The etching process generates quite a bit of heat. While I can't speak specifically to your "system", I can tell you that using commercial equipment, solution, and stencils, the marking should be done in short "bursts", lest you destroy the stencil and dry salt out in the mark through overheating. There are also bubbles produced which need to be vented. Commonly, the electrode is applied for 1-3 seconds, then removed for a few seconds. This "pecking" is repeated until the desired depth of mark is achieved. Another common problem new users encounter is finding the right wetness of the pad with the electrolyte. The pad should be damp, not sopping wet; wet it and then blot on a paper towel. Your electrolyte solution sounds exceptionally salty, also. I would take a portion and dilute it substantially with distilled water and try that.
 
I built the craford machine as well and am very happy. I would be carefull with that solution, it is acid and can discolor you knife. I use a tsp of salt and a tsp of TSP is a glass of water. you can use a drop or two of dishwashing soap instead of TSP. The idea is you need a solution that will conduct electricity, it really doesnt take much.

For you probe you only need it to be damp, I wet mine a bit and blot on a paper towle to remove excess.

I agree with Fitzo, dab , look dab, look , dab look. Let the gas out and dont build up heat. I use mine for 10 - 12 seconds. Another thing to think of I think the leads were crossed in his plans or the plans I got. Try to reverse the leads if you still dont get good results.
 
I think you've got too much power going into the etch and are spending too much time in etching.

Like fitzo suggested, only short 1-2 second bursts and then lifting up to let the area gas-off. Also, for repeatable results, change the felt every new etch. I put some sticky-backed hook velcro on either side of the hand piece I made and just attach the felt to it so it's easy to change out.

As for the power, when using Ernie's stencils, I found that the 24V coming from the etcher seems to be too much. It rapidly boils off the etchant and quickly heats up the metal, handpiece, felt, and stencil. I took the etcher apart and wired up a switch to be able to switch between 12V and 24V. It produces much less heat on the 12V setting. You just have to perform more etching "cycles". I use a Q-tip to wet the felt so that it's just a bit damp. Really not much wetness at all, just enough to last through the etching cycles.

I don't think the leads were reversed in the plans, I think he just switched the colors around. In other words, I believe the red banana plug is actually negative and the black is positive. As long as you follow the instructions, you should be ok, at least with my experiences.

Hope that helps.

--nathan
 
You guys just helped me solve a problem I've been having with mine! I got the wrong transformer shipped to me when I built the system. Mine was only a 6V transformer and wasn't etching DC deeply at all.

Thanks!
 
OK I have figured out two things from your replies. I was dipping the felt every few minutes, so it's way too wet and I think way too much salt because the salt was drying in the lettering almost instantly, as some one mentioned that wasn't desireable. I still have to check on the transformer with my son in law.
Thanks evryone for the info now I no a couple of areas to work on.
Still one question I understand the pecking bit but how long would you average on DC and then how long on AC to darken on a particular stencil?
 
With my stencils and 24V, I etched a quick 2 second hold about 4 times and then about 4 more at 1 second. With 12V it's more like 1 second holds about 20-30 times. It's going to vary, so try it out on some scrap steel finished at the same level as you blade.

AC I would hold for 1-2 second holds about 10 times. Start there and increase/decrease to your taste.

--nathan
 
Fiddleback said:
You guys just helped me solve a problem I've been having with mine! I got the wrong transformer shipped to me when I built the system. Mine was only a 6V transformer and wasn't etching DC deeply at all.

Thanks!
Click to expand...

I etch at 5V (5V 2.5A DC wall wart) without any problems...

CHeers ROdy
 
For what it's worth, you can simply take a 9V or 12V battery and hook up wires with alligator clips to your existing etcher pad. It works well and will give you a deep etch. Switch to AC on your machine to darken.

--nathan
 
I just checked the recycled charger that I use. 7.5V@ 100mA. I use nail polish and a brass scribe to make make my mark. Hint: make your make in the nail polish (I stole from my wife's Mary Kay stash :eek:) before it completely dries. If it completely dries, it tends to chip. After scribing the mark, I let it completely dry. For the pad, i use a q tip and the dab technique, moving it around and making the etch look even. The etchant I use is the ferric chloride (radioshack) diluted 1:2

I learned this from a knife maker (Moran) up in the Santa Cruz mountains.

Have fun.

Ric
 
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