DC etching machine

[fisherpard]

I have been using a AC etch-o-matic to mark my blades but it works ok sometimes but is not consistant. I have heard that DC works better.

I have a Radio Shack current converter that converts AC to DC. Could I hook up leads from this with a stamp pad on the hot and a alligator clip for the blade with the other. Do you think this might work.

thanks,
fisherpard

priderock@charter.net

[mrmanners]

Not sure if that would work or not but you can get the parts at Radio Shack to build an etcher. You can get the plans from www.chriscrawfordknives.com then go to his tutorial section. I built one about 8 months ago that works great.

[SKIVIE]

I built the same one and Chris' Tutorial makes it really easy to build. I think it cost me around $60. Good luck.

Shane

[Drac]

Unfortunately you need both DC & AC to do a good etch. The DC removes the material, the etch. The AC removes & adds material as it cycles, the marking. Any unit you use should have a switch between the two.

Jim

[B.Finnigan]

I have not had good luck with electro etching either. It is amazing how deep the etch goes when you have to buff out a screwed up etch. I can get a perfect etch on one knife and the very next one using the same stencil and process screw it up. I have tried different stencils, units and electrolytes and the only conclusion I can draw is that the whole process is inconsistant. I will be getting a metal stamp from Evers very soon. It is all about picking your battles.

If you do want to try etching don't get a Martronics unit, thier tech support is nothing short of a train wreck. On my first call to them they told me to develop the stencils for a longer period of time but they have not got around to updating the instruction manual with that info. In thier minds that was just a minor detail. That was after I screwed up an entire sheet of stencil film.

[Ray Rogers]

I have used the Etch-O-Matic for the last 10 years and get great results with it. This unit, like any other commercial etching unit, uses both AC and DC current to produce the etch. The DC current is applied when you attach that extra little alligator clip to the clip built into the unit, the extra clip acts as a diode to create the DC. Whatever your problem may be, I would be very surprised to find the etcher was the cause of it. All commcercial etchers that knifemakers normally buy or build work exactly the same way. Some have a little more power than others and can burn a deeper etch or do the etch a little faster but that's it. None will give a 'better' etch than another if they are all used properly.

Proper use will include having high quality stencils, etchants that match the type of metal being etched, and the proper timing and techniques for applying the etch. We can discuss the best way to use the unit here if you wish but it has all been spelled out in great detail in other threads. The Search button can help you find these threads. After that, if your results don't improve, tell us exactly what you do and what the results are and we'll try to figure it out...

[fisherpard]

I went to radio shack and purchased all the parts on the list. It almost looks like the AC to DC converter that I have from Radio Shack with the exception of not having a switch to change the current to AC. It is one of the strongest they sell, I believe it puts out 13 volts.

How much current will I get on DC with the one I plan to build? I was just wondering compaired to the Personalizer Plus does it rate??

I do have a question about the Etch-O-Matic. I did not know that about the extra clip. I tried it a few times and did not notice any difference and now have misplaced it. Does it take a special type of alligater clip? Can I buy one at a Hardware store or will I need to order one from Martronics. I do get some good marks from the Etch-O-Matic on some steel but it seems not consistant. I also have the stencil maker from them but have yet to make a good stencil. I get my best results from a typewriter stencil. I wished the Etch-O-matic had a way to have the control to change from AC to DC.

all advice appreciated,
fisherman
priderock@charter.net

[Drac]

On the etch being messed up by buff, not many people buff their blades & I stopped once I was shown how to do a hand finish. I do remember that every time I buffed a blade after etching it did mess up the etch. Even factory etches can be buffed out. All compounds are still abrasives & can get into the little area of the etch. I go over mine with the same sandpaper grit I used for the final finish to sharpen up the etch. Since I flat grind I back it with Dymondwood (yes I found a place for it ) so it doesn't go into the etch. One or two passes usually does it.

There was a real good article in one of the last two issues of blade where Bob Warner covered his etcher (check out http://www.knifenetwork.com/workshop...h_warner.shtml )

Jim

[B.Finnigan]

The alligator clip has a diode inside the heat shrink to convet the AC to DC. IMHO it is a stupid idea vs. building in a DPDT switch to do it. If you contact the company I am sure they can send a replacement to you. You could buy a diode, heat shrink and aligator clip at Radio Shack but it would probably cost the same as a pre-made replacement from the company.

[Ray Rogers]

If I remember correctly the Etch-O-Matic puts out 12v on AC and 6 on DC. DC voltage will normally be half of the AC voltage on most if not all of these machines. The Personalizer, I believe, is 24 AC and 12 DC but all this gives you is a faster and deeper etch. It has nothing to do with the quality and clarity of the etch. That's all controlled by the quality of your stencil, proper matching of the electrlyte an metal to be etched, and the actual etching technique you use.

Yes, a switch on the Etch-O-Matic would have been nice as a convenience but it won't make the mark any better....

[alexkuzn]

Originally Posted by Drac

On the etch being messed up by buff, not many people buff their blades & I stopped once I was shown how to do a hand finish. I do remember that every time I buffed a blade after etching it did mess up the etch. Even factory etches can be buffed out. All compounds are still abrasives & can get into the little area of the etch. I go over mine with the same sandpaper grit I used for the final finish to sharpen up the etch. Since I flat grind I back it with Dymondwood (yes I found a place for it ) so it doesn't go into the etch. One or two passes usually does it.

There was a real good article in one of the last two issues of blade where Bob Warner covered his etcher (check out http://www.knifenetwork.com/workshop...h_warner.shtml )

Jim

Can I find this article online?

[Txcwboy]

I bought an EtchOmatic on ebay used for 7 bucks delivered ! with no fluid though. I havent tried it yet due to needing fluid. Do you have to use special fluid or can I get something to work locally ?


Dave

[Ray Rogers]

I have heard that salt water can be used but I haven't tried it. There are different electrolytes made commercially for carbon steel, stainless steel and non-ferrous metals. I buy mine from Sheffield's Knife supply, they sell the Etch-O-Matic and the chemicals made specifically for it. It's not expensive and it lasts nearly forever. Been using the same bottle for years...

[Andrew Garrett]

I have the Etch-O-Matic and the stencil making set-up as well. I use the etchant that came with the unit on all the steels I etch.

My screw-ups have been in in two areas:

First, DO NOT do the extra exposing of the stencil with the lamp or the hair dryer that Martronics reccomends. It makes the stencil brittle and will cause hair-line cracks in it which are very hard to see until you are trying to figure out why you have hair-line black lines coming off your newly applied maker's mark.
Second, be careful about over etching. At first I didn't want to under expose because I figured the best result would be achieved with one good burn. I have since taken to taping my stencil down and taking baby steps. I will burn a second or three and take a look at it. I will then use the corner of the pad to etch those areas which need a bit more etching. Once I lift the stencil, the game is over, win or lose.
If I over etched it, I do a few bumps on the buffer (I guess I'm one of the few who buff my blades).

I have given up on etching damascus for now.

[B.Finnigan]

On the etches that did turn out I have used some Dursol polishing paste to clean up the small hairy edges a bit. It also tones down the black to a dark charcoal color which I like better then the harsh black color.