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rlobrecht
01-03-2017, 10:05 AM
Although not quite Star Wars or lightsaber related, the lessons learned still apply.

I have two Starbucks brand steel insulated coffee cups. They are 16 oz, and are straight cylinders. Despite washing them by hand, the paint started chipping. This past fall they got to the point where they looked pretty bad, so I decided to strip all the paint, and etch designs into them. After a little Google-fu, I found that the techniques in ARKM's tutorial (http://forums.thecustomsabershop.com/showthread.php?13430-ARKM-s-Saltwater-Etching-Tutorial&highlight=arkm+etch+tutorial) should work on stainless steel.

I fired up my wife's Cricut machine to make some stencils, and used packing tape for the remainder of the resist. I didn't have a long steel bar for the negative side, so I used a straightened staple. It ended up being about 5" long.

The etching seemed to work fine. I got bubbles, and the water turned really gross. So gross, that I couldn't really see the progress. After about 9 minutes, I decided I had waited long enough. I pulled the first cup out of the mix, and rinsed it off. All the areas seemed to be etched, so I pulled off the resist. I found that it was etched, but not as much as I wanted, and the back side didn't get etched much at all. I remembered that the most etching would be on the face close to the negative pole, so for the second cup, I decided I needed to leave it in longer, and turn it so the different faces faced the negative pole. Since I was leaving it longer and turning it, I went from 9 minutes to 27 minutes, and I rotated the cup a little every few minutes.

At the end, I pulled the cup, and water came pouring out of one side, I got a nice deep etch this time, but in a few spots, the etch was too deep and etched completely through.

Looking back, I should have been checking it a little more carefully by rinsing it part way through.

From my recollection, aluminum etched faster, so I could see the same thing happening when etching a saber body.

Lessons learned:
-the face of the part closest to the negative lead etches the fastest
-you can etch completely through the part

darth_chasm
01-03-2017, 10:44 AM
One way to get around having to keep turning the piece to face the cathode is to use heavy gauge wire of the appropriate metal and coil it around the ID of your container.

Just got the Cricut Explore Air btw. Haven't etched yet, but I'm pretty pleased with the cut.

jbkuma
01-03-2017, 11:25 AM
I've debated doing this on purpose to clear out some material. I know it wouldn't be perfectly clean, but it could save a lot of manual work by, if nothing else, thinning the bulk and giving an edge to work to.

ARKM
01-03-2017, 12:04 PM
rlobrecht, sorry to hear it. I've had that happen with brass sink tube before. It sucks.

darth_chasm, I don't think that wrapping the wire around the inside of the container is a good idea. I have tried using three rods for the cathodes, in a triangular fashion, all split from the same point on the main wire with an equal amount of wire leading to each rod. This did not help the etching process and caused the battery charger to trip it's internal, automatically resetting breaker, more often. I'm guessing that this has to do with the flow of electrons. They "prefer" moving in straight lines. I have also tried two rods with similar results. One 1/8" dia. rod has always worked best in all my tests. However if there is etching do be done all the way around the piece, I do rotate the piece every so often.

darth_chasm
01-03-2017, 12:57 PM
Interesting. I admittedly have not done it with etching yet, but it is the same set-up I use for plating to get a fairly even plate on all sides and it works very well. Have not run into any electrical issues. I use a bench power supply. Don't know if that makes any difference.

I'm a rebel, so I think I'll try it out when I'm ready to etch to see what happens. If I blow up the apartment I'll blame it on faulty gas lines. ;)

Greenie
01-03-2017, 12:59 PM
I find rotating the work piece at regular intervals usually works well. I submerge in a large coffee jar but Im wondering now if a metal container could be used connected directly as the negative (?)

jbkuma
01-03-2017, 01:23 PM
I read a post once that suggested a cheap pot could be used if you had a good way of suspending the work piece. That was before I discovered there was actually a saber smithing community, and many of the things I was editing lexperimenting with were old hat.

ARobb73
01-03-2017, 02:26 PM
I've debated doing this on purpose to clear out some material. I know it wouldn't be perfectly clean, but it could save a lot of manual work by, if nothing else, thinning the bulk and giving an edge to work to.

I did this to randomly simulate blaster damage on a saber, then covered it with a sink tube shroud to make it look like a 'quick' in the field fix. The random munching of the non-resisted metal really made it look pretty neat.

jbkuma
01-04-2017, 09:20 AM
I had been debating picking up a coil of aluminum tubing to try. It's pretty cheap, so if it doesn't work out so be it.
14754

rlobrecht
01-05-2017, 06:16 AM
Let us know how it goes.

Darkw1ng69
01-15-2017, 08:56 AM
Hello guys. I have looked all over for this one particular video where a guy acid etched a rebel logo onto his saber and now I can't find it. In the video he used this blue transfer film and baked it on.Can anyone help me?

PhoenixHawk
01-15-2017, 01:29 PM
That would be ARKM's Saltwater Etching Tutorial thread.

http://forums.thecustomsabershop.com/showthread.php?13430-ARKM-s-Saltwater-Etching-Tutorial

rlobrecht
01-16-2017, 08:17 AM
To save you some time, I have a Brother printer, and found out after much experimenting and searching that Brother toner doesn't work with PNP Blue transfer paper.

ARKM
01-16-2017, 12:53 PM
That would be ARKM's Saltwater Etching Tutorial thread.

http://forums.thecustomsabershop.com/showthread.php?13430-ARKM-s-Saltwater-Etching-Tutorial

Actually I did not use the PnP transfer paper in my tutorial, nor are there any videos as part of my tutorial. I appreciate the plug though. :)

I have tried the PnP paper but I can't get it to work well for me. Others have had much better success with it than I.

PhoenixHawk
01-16-2017, 03:08 PM
Opps...missed seeing the blue transfer film part. In my opinion you don't want to use that stuff...its a pain to work with and like Arkm said sometimes it works and most of the time it dosen't. Just get a vinyl cutter like darth_chasm did. Have seen many members use them and they work very well. I'm going to get one once i can afford one.

darth_chasm
01-24-2017, 11:10 AM
I was cleaning up a bit and found the container I used to etch DCLS-004. I then remembered I used coiled wire to etch the entire body. I must have forgotten because it wasn't a design per se. No mishaps that go around.

I am currently etching right now. Unfortunately, I don't have any thick gauge brass wire so I am using two plates (wish I had three) connected by some copper wire. Same concept as a coiled wire, just a different config.

Everything seems to be going fine.

http://i1318.photobucket.com/albums/t649/DarthChasm/Misc/IMG_1448_zpser09vqh7.jpg (http://s1318.photobucket.com/user/DarthChasm/media/Misc/IMG_1448_zpser09vqh7.jpg.html) http://i1318.photobucket.com/albums/t649/DarthChasm/Misc/IMG_1449_zpsic8ratpm.jpg (http://s1318.photobucket.com/user/DarthChasm/media/Misc/IMG_1449_zpsic8ratpm.jpg.html)

UPDATE:

Everything worked out alright using the two plates. But because I only had two plates and they did not wrap all the way around I did turn the piece a few times. This is the result from 1hr 20 mins. I also did a little light weathering to bring out the detail.

http://i1318.photobucket.com/albums/t649/DarthChasm/DCLS-005/IMG_1450_zpsyaqww1o8.jpg (http://s1318.photobucket.com/user/DarthChasm/media/DCLS-005/IMG_1450_zpsyaqww1o8.jpg.html)

PhoenixHawk
01-24-2017, 10:56 PM
Looks like it turned out great bro...now i want a vinyl cutter even more now. Cool power supply ....what one is it?

darth_chasm
01-24-2017, 11:16 PM
It's a Tekpower. Model # is in the pic. Around $90 on Amazon.

rlobrecht
01-25-2017, 07:03 AM
Looks great. Thanks for sharing.

ARKM
01-25-2017, 11:57 AM
1 hour and 20 minutes? Dang! Were you only using 1 volt? I usually use 6. Since I use an old car battery charger, I have no idea what the current is. I need to a get a power supply, lol. Nice etching btw.

darth_chasm
01-25-2017, 12:16 PM
Thanks.

Yeah it was around 1.5v at a constant current of 1 amp. I read on some jewelry sites that a lower voltage produces cleaner lines so I gave it a try. The power supply was one of my best investments. Etching, plating, testing. It comes in handy quite often.

PhoenixHawk
01-25-2017, 06:34 PM
Thanks DC....great another item to add to my wish list. lol