Etching Blades

[Spunjer]

i know this has been discussed a million times before,but when you etch, say a sword, do you apply the acid solution once (in this case, i use radio shack's PCB etchant), and leave it on the blade for a few minutes, or do you constantly brush the solution on the blade until it's time to neutralize it? what are the different methods that are used here?

[Rick]

Hi Spunjer ,
When I etch for pattern with FECL I keep the solution moving constantly with a brush .
Oxygenation makes the stuff work better I have found .

Also if you're trying to bring up a particular area such as the midline pattern on a kris using a Q tip will keep the etchant pretty much confined to where you want it to go .

That is how I enhanced the center pattern on this blade .

[Spunjer]

for how long do you leave the etchant on the blade and what ratio (FECL/water) do you use? the last time (only time, actually) i use 3:1 and the blade turned yellowish...

[Rick]

I don't think there's really a set ratio as different steels react in different times and ways with fecl .
I always start out with 20% fecl or less .
I always mix only with distilled water .
You can always boost the ratio from there .

Just keep the solution moving on the blade surface .

The only piece I have let stand in a solution was a contemporary Indian kanjar with a bird's eye damascus pattern , I was looking to make a topographical etch and it worked in about 30 minutes .

[Federico]

I use the brush method myself, though usually cheap tooth brushes. Always helps the solution find those little gaps, and stick better if its agitated just a bit.

Heating the blade also really helps the etch to take hold. You can use a blow dryer, or if its hot and sunny out leave it in the sun a bit. Ideally heating the solution would help too, but that is more a factor with weaker acids, like vinegar.

As for concentrations, I use powdered FeCL and mix my own solution. I normally cut it to a 50/50 solution. If its too strong, then the blade builds a thin layer of oxides extremely quick eg. turns black, but I stress its a thin layer, and ironically the quick build up of oxides prevents further etching as the etchant will sit on top of the oxide layer and not go further in. Anyways, try different acids out, as different blades sometimes react better to different acids. I usually switch between lemon juice and FeCL. Lemon juice may surprise you if you havent tried it, as it is a very strong etchant, but sometimes tends for a more whitish color. I use it for initial cleaning etches, particularly if the blade is rusty (it can eat the rust without leaving large oxide deposits like FeCL). FeCL tends to be more black, and I really only use it if lemon juice doesnt give me the right color. Naval Jelly gives a grayish look. Etc... experiment.

I also recommend multiple short etches (let the blade soak 2-5 minutes), followed by light oxide removal (I usually remove with 2500 grit paper lubricated with a fragrant oil). Sometimes one etch is just perfect, but if not multiple etches are safer than one real long soak as it allows you to fix things in case something goes wrong. It also allows you to adjust the coloring, darker or light as your taste.

If you are really worried about damaging an inlay, or plated fittings, you can always seal them with a little clear lacquer or epoxy (crazy glue works). Easily removed with acetone.

Hmm...oh yeah dont forget make sure it is absolutely grease free. I normally wash the blade with dishwashing soap, then wipe it down with Isopropyl.

[Spunjer]

thanks for the reply, federico. another confusing aspect of etching that's been bugging me is this; do i polish the blade before etching, or do i polish it later? on the last kris i acquired, this is basically what i did:

• sprayed the blade with wd40 and scrubbed with 0000 steel wool

• washed with diswashing soap and water, then scrubbed it some more with 0000 steel wool

• thouroughly dried the blade with blow dryer, esp. where the metal and wood meet

• polished the blade with metal-glo, using cotton balls and small circles

• applied rennaisance wax

so if i want to etch it, do i remove the wax (by heat and rubbing alcohol) and etch it at this point? btw, i'm just using this blade as an example. i'm actually hesitant etching this particular sword due to its 'tiger' pattern...

[zelbone]

MAAS is a polishing paste similar to Simichrome and Flitz. It's pretty good stuff and polishes metal really well. The only problem with those three in preparation to etching is that they all leave a protective coating on the blade. If you use MAAS, Flitz, Simichrome, et. al, make sure you clean off the blade with something like methanol, isopropyl alcohol, etc. to take off the protective coating left behind with these polishing pastes.

I've never had the opportunity to use an ultrasonic cleaner...sounds intriguing.

[donutsrule]

Here are some before and after pics of my kris and what a few days of MAAS and some elbow grease do. It's not a true before and after becase it's the other side, but the sides were in similar condition. Actually the "after" side looked worse before I started on it.

This is the "before" side:

[donutsrule]

And here is the "after" side. You can see not only is there the brazing that left the scorch marks, but there was another, smaller, "repair" done above that with copper rather than brass.

[Spunjer]

what happened to that kris? did you brazed it yourself???

[donutsrule]

Originally Posted by Spunjer

what happened to that kris? did you brazed it yourself???

Absolutely not. It was [afaik] a WWII bring-back I purchased off Ebay like that. I don't know when it was ... "repaired."


Edit: here's another pic that shows the pretty nasty condition it was/is in when I got it.