Applying the Resist and Etching

Adding the "Resist"

Now that I had the pattern I wanted on the blade, I needed something to mask the rest of the blade with.  My first thought was beeswax, but it's too thick unless you thin it with some turpentine, but to get it thin enough to use it won't harden.  The answer - heat.  beeswax melts at 140 - 145 degrees or so.

A few trials, and what I came up with is to use 1 part beeswax, 1 part paraffin wax, and 1 part turpentine, and heat it to just over it's melting point in my "Hot Pot":

The result is a mixture that flows onto the blade fluidly, hardens quickly after application, and finally is removed easily after the process is complete.

The first job is to take care of those spots that didn't come through with the transfer film.  Using a brush I cut to a point, I spot in those areas with my homemade resist:

When I have covered all the exposed areas on the pattern, I move on to coat the rest of the blade with the resist using a 1" wide artists brush, being sure that every possible spot on the blade is covered.  Whatever isn't will be etched - I had one of my first experiments leak all over, and pretty much ruined the blade.  Here you can see how the resist should flow on:

Once fully covered, the blade is ready to be etched.

Etching

Now comes the fun part.   Also, the easiest - the actual etching.  The etching solution I used is Ferric Chloride - not technically an acid (I don't think, anyway - I'm no chemist!) but a corrosive salt.  It's still quite potent, but not as dangerous as acid can be.  It can be purchased at the local Radio Shack as "Etchant Solution" for about $5 a pint.  I got 2 pints to make sure I had enough, and some rubber gloves - I don't believe that Ferric Chloride is that harmful to your skin, but will turn your skin a nasty brown - and I would hate to get it into a cut.  Use at your own risk - if it eats metal...

I found a plastic container that would hold all the blades, and placed the blade into the solution, with the artwork facing down and one edge propped up on a plastic putty knife:

The putty knife is to keep the image off of the bottom of the pan - the etchant works best if it can drop its "etchings" down, hence putting the blade in with the image down.  Let it sit in the solution for about 10 minutes, then remove it and wash it off under running water, or in a similar container with fresh water.  Be careful how you handle the blade, as just about any exposure to the etchant will leave it's mark on it.

Clean-Up

Once rinsed off, clean up is a breeze.  First, I use a putty knife to remove the largest part of the wax resist:

It peels off easily, and I just chuck the scrapings off in the waste bucket.  Once the majority of the resist is removed, some 00 steel wool removes the rest, including the resist left by the transfer film (with a little extra scrubbing!):

Once all of the resist is removed, I clean the blade off with some Windex (glass cleaner) to make sure that there is no trace of etchant remaining on the blade.

Here's the final result:

Summation

This was not as easy as all of that.  To be honest, I only had about a 20% success rate with the transfer film.  It could be that I wasn't getting enough toner transferred to the film, or not getting the heat quite right - I don't know for sure.  In any case, it's not good enough of a success rate for me to continue on with it.  All is not lost, however - there are a couple of other solutions I am going to try.

First, this was a "dry" process sheet.  The same company, Techniks, Inc., also makes a "wet" process transfer film that work quite similarly - and that I've placed an order for (I will update this article when I have something from that).  Another company also make a wet process that is almost identical - Pulsar (see web site at pulsar.gs)

Still, it did work, even though it took a few tries.  All in all, I have 5 or 6 blades with a logo etched on to them now, more than I had before.  And I have the benefit of the experience. 

There are also entirely different methods, such as using a UV sensitive photo-resist that I may yet try.

Hope this was useful information.  More to come!

Update:

I'm happy to report that I was able to achieve a better than 80% success rate with the wet process system.  The procedure is almost identical to the above, with the exception that when you throw the blade in the water to cool after ironing it, you allow the paper to soak up as much water as it can before peeling it off.  Here's a shot of the mask applied with that process:

I also found that dipping the end of an old dried out felt-tipped pen into shellac and using it like a small brush was a good way to fill in small holes in the mask...

It's taken me a couple of days, but I've now etched about 30 blades using the above process.

Thanks for reading!