Dave SmithPosted by Mike Jackson on December 28, 2003
Here's a photo England's Dave Smith sent yesterday. He asked me to post it and he promised to come on the board and explain a few processes.
The look great to me!
Mike
Larry White - Order of ProcessThanks Mike for posting here for me.
I now know how to place pictures on the site thanks to you.
I will try to explain what I did. Basically
all the panels were firstly glue chipped using
the asphaltum method, then the gold panels and some of the smaller text were acid- etched with mica flakes for 35 minutes.
Next stage after cleaning all the glue off ,I applied vinyl to the lettering areas leaving enough space for the outline to show .
I then silvered over the entire piece right to the edges,painted the back with specialist mirror- backing paint (No need for copper backing or shellac).This paint starts to dry within 5 minutes but keeps soft for up to 1 to 2 hours. The vinyl was pulled away which softens because of the type of paint and releases from the glass perfectly with sharp edges to the silver glow lines.
You can fill in letters with whatever colour.I then airbrushed asphaltum glaze on the large ribbon panel to give depth.
Gild your lettering and acid- etched panels taking care of any misses, scrape off the tops of the lettering within the gold panels with a stanley blade or razor blade and paint in those areas withwhat ever colour.The detail you can achieve depends on your plotter-I manage to get down to 3ml text with no problems .
Any finer than that I would use screen printng using asphaltun varnish printed 3 times without movement,like acid- etched gilded factory details which Rick used.
Finally paint and finger blend backgrounds and lettering.I have found this method to be faster than screening on big jobs obviously saving on screen printing set ups .I forgot to mention I silvered the glass 3 times each for density and longevity.
Thanks for your comments Danny see you at the Conclave.
Hope this all makes sense!
Merry Christmas and Happy New Year from over this side of the pond!
Dave.
Dave Smith - Order of ProcessHi Dave, thanks for the post. I've typically done my acid etching prior to glue chipping, but you mentioned it the other way around. What I typically do is to mask my glass leaving the positive areas to acid etch, coat with asphaltum and weed, then do the mica etching. After etching I mask over the glass (and asphaltum) with my sandblast mask (which masks the acid etched areas), sandblast, pull the mask and flow in the glue for chipping.
If you're doing the acid etching after the glue chipping, are you just using the vinyl as a mask without using asphaltum? Thanks,
-Larry White
Robare M. Novou - Order of ProcessI think either way works fine Larry.
I like to Glue Chip first then wipe away my asphaltum, place the vinyl straight to the glass
masking out the glue chip etc...always had a crisper edge this way. I have had the asphaltum break down sometimes before the 30-35 minutes are up. Have you ever had the acid etch into unwanted areas Larry.
Dave
Larry White - Acid Etching SandblastVery Nice Panels Dave!
Pondering which to do first, the acid or the chipping? Some past projects screw-ups have convinced me to do the acid etching first.
When doing the acid first, some of it went underneath the asphaltum and ruined the glass.
Had I done the chipping first and then the acid, I would have been out the time and cost of not only the acid etching but also in doing all that chipping work. So in summation, I etch first, chip second.
I might also add that I coat-out my glass with two coats of asphaltum and let it dry for 2 or 3 days before doing any etching. Letting the asphaltum dry helps me in achieving perfect etching.
I'm thinking that this is what a lot of you folks do also.
Another time I etched, the acid went underneath my glue dam and smooth etched the area I would be chipping. I had previously sandblasted this area in preparation for the glue. I thought that it would not matter, and that the glue would still stick to this area of leaked acid. No such luck, the glue upon drying easily curled off as if the area had been smooth glass. Needless to say, I had to reblast these leak damaged areas to get the glue to stick.
I do get good crisp edges, what I have noticed is pinhole etching, little pin point pricks of etching in the areas that had been coated with asphaltum. The longer I leave on the acid the more pin points I notice. These are of course on glass that has been screened coated twice with asphaltum, no vinyl used. I examine them prior to etching, checking for spots that may cause this, and touch up thin areas just in case, still...tiny pin points, but not all the time.
Yeah, maybe I should screen it 3 times.
Also, on another piece, after coating out with asphatum, and covering with vinyl, I sandblasted the areas I had peeled the vinyl design off. Some sandblasted areas would recieve the acid first, the remaining sandblasted areas would be chipped.
Do you think the acid would have smoothed out the sandblasted area back to clear...no it did not.
I just became a smoother matte finish, no clearing. I didn't silver it, because I dont know if the silver would have stuck to it. has anyone silvered such a way, and if so does it work?
RMN
Robare M. Novou - Acid Etching of SandblastAs an experiment, I tried smoothing out some depth carved (sandblasted) characters with liquid hydroflouric acid. It did not bring the glass back to clear, however it did reduce the sandblast texture considerably. I then did a lead nitrate deposition on the characters. Although they were more of a matte variety than a mirror, they had the look of cast pewter. This is the technique I used on my Conclave XVIII piece (which can be seen under the "Commemoratives" catagory in the walljewelry website). I suppose they would have looked brighter if I had silvered them. I haven't tried that yet, but the lead worked well.
In my previous post when referring to acid etching, it was in conjunction with the mica flakes to create a texture. I have adopted calling the "mica" process "acid etching" and using straight liquid acid as "acid embossing". (I don't know if that's correct terminology or not.) I go about acid embossing slightly differently, but still do my acid work prior to glue chipping. I have also found I like to apply the asphaltu with a japan brush over using a roller. You get a lot less pinholes.
-LW
Conclave XVIII piece
http://www.walljewelry.com/cmConclave.html
Very Nice Piece Larry,
How was the saw tooth edge achieved? And was that cut into the glass or a wood frame?
Larry White - Saw Tooth EdgeIn acid etching/embossing glass, what is the strongest acid available?
Is 50 percent the highest?
Robare M. Novou - Saw Tooth EdgeYes, the saw tooth edge was carved into the glass (it is a "stand alone" piece of glass, no frame). First, from the front of the glass, I masked off (heavy rubber resist)the shape of the piece 1/2" larger than my estimated completed size. I took a large nozzle (1/2") sandblaster and encircled the mask until I blasted all the way through and all the way around. This gave me the shape I was after. I then pulled the 1/2" margin off and took a fine tip (1/16") sandblaster and went around the edge carving in the serations. It took about 10 minutes to blast out the initial shape and about 2-3 hours to add the seration detail. The border has been water gilded with Rouge gold.
I have heard of stronger HF available, but 48-52% is most common and available. I'm not sure where you could get the even stonger stuff. Ask Pat Mackle, I think he knows (he'll probably throw in a free HF horror story too!)
Larry White - Cutting Shapes out of GlassSorry about the double posts, seems things weren't posting or so it seems. so I typed it again, still nothing, I gave up, now I see it did post both times. Computers!
Anyway....I've heard of 72 percent, used with hot water. Makes a very tenatious etch along the edges of the asphaltum, just like your sawtooth boarder Larry. Thats what got me thinking on how you might have done it. I see the same kind of etch on these modern day reverse glass beer signs.
Which brings to mind this thought....has anyone every worked or knows someone who has worked at one of these modern day glass sign factories?
And where might such a factory be located..some of the sigs I have mention California on the back side.
I had a chat with the guy I used to work with today. He says hes in charge of the acid room now.
So hes gonna find out all the details for me on 72 percent acid.
I think the process of using 72 percent was patented, I did see the patent hanging on the wall, cool certificate. I gots to get to the library, and no, I dont remember the Patent #. And they took down the certificate from the wall!
Larry, have you seen those stained glass bandsaws that can cut any shape of glass you can think of, they're the ones with the diamond coated wire. I thought thats how you might have carved the shape out on your piece.
RMN
Danny BusselleYes, I've seen those glass band saws, but have never used one. Seems like it would take a long time to cut out a shape. I've always used the sandblast method 'cause that's what I had available. Another thing we've used is water jet cutting. They can basically take any vector file and cut the shape out of glass. There's a few people around that do that. I'm not sure what they charge. We've used Creative Cutting out of Watsonville CA. and have always traded their services for our sandblasting services. -LW
Happy New year.. and it appears that "Davey Smith" Has Gone Trick on us again. Love it. Keeps my Blood Goooin. Tell us the Process or even Better, Bring them to California. of course its much cheaper to just explain how it was Done so I can Go do some. Very HOT Dave..
Denver Chapter of the Letterheads