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Adding the "Resist" Now that I had the pattern I wanted on the blade, Ineeded something to mask the rest of the blade with. My first thoughtwas beeswax, but it's too thick unless you thin it with someturpentine, but to get it thin enough to use it won't harden. Theanswer - heat. beeswax melts at 140 - 145 degrees or so. A few trials, and what I came up with is to use 1 partbeeswax, 1 part paraffin wax, and 1 part turpentine, and heat it tojust over it's melting point in my "Hot Pot": The result is a mixture that flows onto the bladefluidly, hardens quickly after application, and finally is removedeasily after the process is complete. The first job is to take care of those spots thatdidn't come through with the transfer film. Using a brush I cut to apoint, I spot in those areas with my homemade resist: When I have covered all the exposed areas on the pattern, I move onto coat the rest of the blade with the resist using a 1" wide artistsbrush, being sure that every possible spot on the blade is covered. Whatever isn't will be etched - I had one of my first experiments leakall over, and pretty much ruined the blade. Here you can see how theresist should flow on:
Once fully covered, the blade is ready to be etched. EtchingNow comes the fun part. Also, the easiest - theactual etching. The etching solution I used is Ferric Chloride - nottechnically an acid (I don't think, anyway - I'm no chemist!) but acorrosive salt. It's still quite potent, but not as dangerous as acidcan be. It can be purchased at the local Radio Shack as "EtchantSolution" for about $5 a pint. I got 2 pints to make sure I hadenough, and some rubber gloves - I don't believe that Ferric Chlorideis 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 iteats metal... | Notice - Ferric Chloride Be warned - Ferric Chloride is a nasty chemical, andshould be treated as such. Use extreme caution whenever using. Pleaseresearch and use all safety procedures recommended. I cannot beresponsible for your use of hazardous products. MSDS for Ferric Chloride (PDF format):
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I found a plastic container that would hold all theblades, and placed the blade into the solution, with the artwork facingdown and one edge propped up on a plastic putty knife: The putty knife is to keep the image off of the bottomof 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 thesolution for about 10 minutes, then remove it and wash it off underrunning water, or in a similar container with fresh water. Be carefulhow you handle the blade, as just about any exposure to the etchantwill leave it's mark on it. Clean-UpOnce 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 offin the waste bucket. Once the majority of the resist is removed, some00 steel wool removes the rest, including the resist left by thetransfer film (with a little extra scrubbing!): Once all of the resist is removed, I clean the bladeoff with some Windex (glass cleaner) to make sure that there is notrace of etchant remaining on the blade. Here's the final result: SummationThis was not as easy as all of that. To be honest, Ionly had about a 20% success rate with the transfer film. It could bethat I wasn't getting enough toner transferred to the film, or notgetting 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 amgoing to try. First, this was a "dry" process sheet. The samecompany, Techniks, Inc., also makes a "wet" process transfer film thatwork quite similarly - and that I've placed an order for (I will updatethis article when I have something from that). Another company alsomake a wet process that is almost identical - Pulsar (see web site atpulsar.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 betterthan 80% success rate with the wet process system. The procedure isalmost identical to the above, with the exception that when you throwthe blade in the water to cool after ironing it, you allow the paper tosoak up as much water as it can before peeling it off. Here's a shotof the mask applied with that process: I also found that dipping the end of an old dried outfelt-tipped pen into shellac and using it like a small brush was a goodway 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! | 
发表于 2009-6-23 04:43
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