etching question

[Omega]

I read a thread on acid etching (but i cant remember by who :confused: ) in the post this individual used a special ink to write/draw his design then comes tha acid bath and he is left with a flat background and beautiful raised letters and designs. my question is what keeps the acid from eatting away at the side of the raised portions? im not sure im being totally clear but im not sure who to explain the question any better


thanks

bill

[peregrine]

You are correct, that the acid will begin to eat underneath the resist layer. (If left long enough.) You have to remove the blade before this happens. You decide how long to keep it in the bath. How deep do you want the design to go. The longer in the bath, the more the acid will begin to blurr or "enlarge" your design. But on the other hand, the deeper the design is eatten into the blade.

The how long, how deep the etch is what you have to control. The acid eats at various speeds depending on age, light, heat, and type. (Did I forget any?) Therefore, you need to check your resist occassionally to see what is happening. To do this remove from bath and clean out your design with a soft object like a feather, artist brush, etc. (You gain experience on this through time/experience.)

Anyway, that's my 2 cents worth. Hope this helps.
Roger

my site

[rouger 10]

What is the ink called and where can I get some????

Roger

[peregrine]

I've never used ink (though my guess would be Indian ink. ???) Perhaps, someone else will respond who has some experience. I've heard others say, they've used red fingernail polish. I guess it depends on your cutting agent (acid), etc.

I cut my images really deep using a mix of acids. For this, I use a resist of asphaltum, just like David Boyde's book explains.

Good luck!
Roger

[Terry_Dodson]

permenant sharpie pens work for a resist.

[Omega]

if i use a sharpie how deep can i get the cut using say ferric chloride? im pretty sure the time in and the temp matter im just wondering if the sharpie will hold up for a long bath




bill

[Terry_Dodson]

you may have to try it on a piece of scrap to see if it will go deep enough for what you want. as it goes deeper it will start eating at the edges some. but no matter what you use i beleive that will still be the case. you can try finger nail polish or even spray paint or primer, anything to cover the steel. Have you thought about electro etching? there are plans on Bob Warner's site on how to make a home built electro etcher for under $50
http://www.warnerknives.com/electro-etcher.htm

[Omega]

yea i thought about that only problem is for every new design i want to make i need a new stencil

[AwP]

Only if you want the exact design to be repeatable. You can use the same resist methods with electroetching as with acid etching, you'll just need to carve/paint in the pattern from scratch each time.

[Omega]

really? i didnt know you could do it like that, will i be able to get a deep etch with that?

bill

[AwP]

If you do it long enough and have the polarities set right then you should be able to, in theory, though I never had as much luck electro etching as acid etching.

[peregrine]

I have never tried the electric method of etching. How deep can you get it to burn into the steel. Say on a hardened 154CM Stainless blade? Can you get it to bite this deep?
Roger