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Dark Helmet
04-04-2008, 11:35 PM
Warning Etching Of This Kind Might Result In Toxic Gas!!

Only attempt in well ventilated area.


this is a cut and paste, so if anyone complains about it,I'll have to delete this post, but since we have no section on finishing I'll paste it in this one....but it seems a nice way to customize some sink tubes, it say's ferrous metals, but aluminum will take blue even tho it's not supposed to...so i imagine this could work ok on mhs, it will likely cause problems in threaded sections tho...

For etching, we’ll need a liquid conductor, suitable resist and a power supply that can be regulated.

Liquid Conductor:

Saltwater will do fine as it’s one of the more conductive water-based solutions. The conductivity of drinkable groundwater is usually in the range of 30K to 60K ohms. A 7% solution of saltwater has a conductivity of something under 1K ohms which is adequate for our purposes. Increasing the salt solution further doesn’t dramatically increase conductivity.

Compared to acids and other etch methods, saltwater is safe, inexpensive and readily available.

Suitable Resist:

We need something nonconductive and waterproof which can withstand the mechanical action of etching and is easily removable. Traditionally, etching resist was some form of asphaltum. Lacquer spray paint/finish works fine--fast drying and is removed with acetone. Deft and Dupli-Color are two sprays which are suitable. Any lacquer-based spray product should work.

Lacquer seems to work best on ferrous based metals. It doesn’t adhere as well on brass and galvanized metals.

Finger nail polish works well as a resist.

Power Supply:

Save yourself the expense of a commercial DC power-source and just use dry cell batteries. Anything from 1.5V to 9V will work fine. The humble D cell will do everything you want done.

Increasing the saltwater solution and/or voltage won’t make much difference--varying either or both won’t hurt anything, but doesn’t help much either. 1.5V and 7% saltwater will do the trick.

To see how this works and to grasp the fundamentals, round up a 1.5V cell (AA, C or D--doesn’t matter), some leads, a glass container of some sort, a couple strips of ferrous-based metal--iron, steel, nails or some such.

Mix up some saltwater (1 tablespoon of salt in a cup of water, this is the same mixture we used while quenching), spray one of the strips with a couple coats of lacquer-based spray and let dry--a heat-gun speeds things along. Clean the metal with acetone before spraying to get a good bond.

Scratch what you want etched into the sprayed surface. Place the two strips (one sprayed, the other bare) into the saltwater bath and connect the leads. The positive pole of the battery goes to the strip you want etched--the sprayed one. The negative pole connects to the bare strip.

Metal attached to the positive (+) pole will be etched.
Metal attached to the negative (-) pole will produce bubbles.
Cathode is the negative pole; Anode the positive pole.

You’ll see bubbles emanating from the bare strip (cathode -). If they’re coming off the sprayed strip (anode +) then reverse the leads. You'll get a nice mark in minutes. Wait an hour for a very deep etch. Remove the strips from the bath, remove the sprayed material with acetone and inspect the etch. That’s it, that’s the whole deal! The rest is just refinement.

In all etching, the degree of bubbling is the prime indicator with which to monitor the process. Saltwater etching as described above will produce a clean, crisp, deep etch without undercuts.





with this you can make custom designs on your hilts.... i plan on doing some lace work on a new one soon, this seems to be the best method

Dark Helmet
04-05-2008, 10:36 PM
ok, so i decided to experiment with this a bit, the mhs parts will get a much lighter color in the etched areas, but i took some pics of a scrap piece of brass.... i very sloppily brushed some varnish on this, then dropped it right in (still wet)
http://i230.photobucket.com/albums/ee44/darthdouchebag/heatsink2003.jpg

after about 15 minutes and a good washing, this is what brass looked like, not nearly as attractive as mhs/aluminum but you can see fast results from this process.... as soon as the leads are connected you see the brass getting darker (pretty cool to watch). the odd streaks are where the varnish was, remember, i put this in with wet varnish so it was mostly eaten away in the process. with a bit of painting skill this can be a very cheap, fast and easy way to create designs in a hilt. GOOD LUCK!
http://i230.photobucket.com/albums/ee44/darthdouchebag/heatsink2005.jpg

eastern57
04-06-2008, 06:42 PM
I'm not sure I understand what gets etched.
What I gathered is this:
- paint over tube with lacquer/protectant
- Scratch whatever pattern in (because the reaction will eat away at the scratched parts?)
- Electrify

Do I have the gist? I really like the uber-nasty look. I don't think I could mimic that with any paint or weathering...

Dark Helmet
04-06-2008, 07:11 PM
anything unpainted gets etched away, so you could actually just paint a design on in stead of scratching away the paint. the effect can actually be pretty on aluminum, it will have a lighter hazy look to it.

virus692
04-06-2008, 07:17 PM
Warning Etching Of This Kind Might Result In Toxic Gas!!

Only attempt in well ventilated area.

Sohryu76
04-07-2008, 10:40 AM
Warning Etching Of This Kind Might Result In Toxic Gas!!

Only attempt in well ventilated area.

something about Chlorine Gas not being good for you....
bah its just a myth!

(no in all seriousness... its VERY bad...)

Dark Helmet
04-07-2008, 02:17 PM
yeah, I'll edit in the warning into the first post...all that and i miss something that should have been the first thing written in the post.

eastern57
04-07-2008, 07:31 PM
crap, I'll have to wait until summer... still winter for a bit longer here...

But glad you told me before I started. tks.

Dark Helmet
04-08-2008, 04:23 PM
this is a test I did on a 2" mhs piece, so that anyone trying this knows what to expect...

http://i230.photobucket.com/albums/ee44/darthdouchebag/heatsink2027.jpghttp://i230.photobucket.com/albums/ee44/darthdouchebag/heatsink2028.jpg

this works pretty well, so I guess this thread is pretty much just reference now...

Angelus Lupus
04-08-2008, 04:46 PM
Wow, that's really nice. Be sure to show off pics of any other peices you do.

Darth_DevilGuy
04-08-2008, 04:48 PM
how long did you leave it going? that looks like what my glass etching work looks like if I don't leave the acid on long enough, I'd suggest going for longer in the bath if you want a more even/sandblasted look.

Dark Helmet
04-08-2008, 05:15 PM
that was about 45 minutes. I cut it short to check the threaded areas and make sure it didn't damage them or make them fit loose (they were perfectly fine)... next time i plain on doing something much more elaborate.

DarthFender
04-09-2008, 07:11 AM
Looks sweet, DH.

Barmic Rin
04-09-2008, 09:14 AM
I can see alot of wannabe sith lords taking trips to the hospital with Chlorine exposure.....

Looks good though.

DarthFender
04-09-2008, 10:14 AM
I'm feelin' a little.... whoosey......

larams
04-24-2008, 12:32 PM
If you printed out a pattern on a laser printer and then ironed it on to the surface to be etched you could put a copper tube down the middle of the hilt and etch all the way thru. Might be able to get some nice designs not possible with a dremel.

Darth Leximus
04-24-2008, 02:05 PM
this intrigues me, time to suck some poison

enigma1337
11-01-2010, 09:00 PM
so i know this post is old, but i had an idea that may make etching a tad bit easier. Same method and all, just instead of freehand painting the resist on, what about making a design on some colored contact paper (we used to have to cover books with it at school) and cut out the portion that you dont wish to be etched. once the contact-paper-stencil-design is on the piece you wish to etch, then spray/paint it with the resist. once its dry, peel the contact paper off (im not sure how sticky this stuff is so be prepared for some force ;p) and continue with the etching plan here :] hope it helps

Eomund
11-03-2010, 06:46 PM
That would actually work. Just make sure you've got good coverage with the paint. Two or three different coats wouldn't hurt. Otherwise, the saltwater will get through any small bubbles in the paint and produce pitting.

On a side note, a poor paint job on an MHS piece put through the etching process makes for interesting weathering. Check out the three inch section below.

http://i979.photobucket.com/albums/ae272/Eomund_saber/th_2010-11-03_21-43-17_949.jpg (http://s979.photobucket.com/albums/ae272/Eomund_saber/?action=view&current=2010-11-03_21-43-17_949.jpg)

Skottsaber
11-04-2010, 09:07 AM
WAY COOL :D:shock:
That looks like real, Star Wars weathering!