Asphaltum method

[erik winkler]

Could someone give me lgiht in the dark Asphaltum path?
Since I have only read and heard about it, I am not absolutely sure what i am doing wrong.
When I poor my glue onto the blasted area's it flows over the aplied asphlatum like it is not there...
These are the steps I did:

1 ) Applying Senefelders asphaltum with a mohair roller.
2 ) Let it dry for weeks (everytime I experiment with this method, I just do not seem to get it done immediatly).
3 ) Applying the masking.
4 ) Sandblast.
5 ) Remove masking.
6 ) Wipe of dust with a clean brush.
7 ) Prepare the glue and heat it up.
8 ) Flow a thin film of the heated glue over the blasted area's..... and here is where it goes not like planned

What am I doing wrong?
What could be done better, so that the glue will stop flowing when it hits the Asphaltum edge?

Thanks,
Erik

[Roderick Treece]

Eric,
First off it doesn't sound like you did your home work.

If you were very carefull to put just the right amount of glue just right up to the edges you might get it to stay right at the edge but thats a pain in the butt.

It doesn't matter how long you wait after you apply the asphaltum.

I never remove the masking prior to chipping. I think it helps when cutting the glue.

***** After the glue has dried to a rubbery consistancy you trace around the design with an exacto knife cutting through the glue cleanly. That way when it does start to chip it will not (hopefully) plink. Some people cll this the double cut metheod.

All this info is out there.

[Larry White]

Yo, Wink, listen out of your good ear now-

When doing the asphaltum method as described, you need to carefully flow the glue over the sandblast areas using a squeeze bottle.

squeeze.jpg (4.13 KiB) Viewed 19797 times

(picture courtesy of Letterhead Sign Supply)

You flow the glue into the desired areas, right up to the asphaltum edge. Typically, the asphaltum edge will repel the glue. If the glue goes over the ashaltum, it can be trimmed once the glue has gelled. If it goes over just slightly, the glue will just pull the asphaltum off the glass.

The other method is, no asphaltum, mask and blast, flow glue over entire piece, cut the glue at the edge of the mask when gelled, then remove the mask, allow to dry, then chip.

[erik winkler]

Winky here,

Rod, I thought I did my homework.
I use the cutting method, but since I wanted a lot of little details I thought of using the Asphaltum method so there would be no cutting needed, except in a few places were the glue has crossed the border. And when I am using the no-asphaltum method I also cut on the masking edge, but when using the aspahltum, I thought that it was necesarry to remove the masking film first. This seems logic, because otherwise there will be no asphaltum surface to repel the glue.
Ofcourse I was very carefull when I came with the glue at the edges, but it just flowed over. Even with just a little drop....

Larry, I have a few different sizes of glue bottles and they work fine... when I am not burning my sissy fingers through the towel paper.

You flow the glue into the desired areas, right up to the asphaltum edge. Typically, the asphaltum edge will repel the glue. If the glue goes over the ashaltum, it can be trimmed once the glue has gelled. If it goes over just slightly, the glue will just pull the asphaltum off the glass.

I flowed the glue as carefully as I could, right up to the asphaltum edge. But typically with Winky the glue won't repel. So the ammount of trimming after the glue has gelled is exactly the same as the none-asphaltum method. And with those tinny little bits: a trip to crazyland....

There must be an other error that I am not aware of.

[Jerry Berg]

Winky,

It sounds like you are mixing your glue at the wrong consistancy. Is it that thin that it runs over the asphaltum?
Maybe you are mixing it with too much water. Or maybe heating it up too hot, which would render the glue useless.

One 3oz. cup of dried glue
One and a half 3oz. cup of water

Was this your ratio? Heating it up too much might make it too runny also I would imagine.

[erik winkler]

Jerry, My ratio is 1 cup of glue with 1,5 cup of distilled water.
Heated to about 60 fahrenheit??? Long before bubbles start to appear.

[Kent Smith]

If your mix is too thin, you can go to 1.25 or 1 to 1. Sometimes letting the glue sit in the cold water to expand longer, even in the refrigerator overnight, helps to control the flow. I only heat enough to get it to flow out of the bottle. Sat. at Gary's meet, we were applying very thick glue with great results. Typically I like it to be like thick molasses. Too hot a mix just makes it flow out too thin to have the strength to chip. Asphaltum just helps to stop the creeping over the lines but will not stop it.

[Danny Baronian]

Rod's right. Looks like you need to carefully re read the notes.

Go here: http://www.theletterheads.com/glawson/gluechip.html

read step 4. Temperature is listed in fahrenheit. Start with the maximum temperature, as lower temperatures, especially on larger pieces will produce an inconsistent chip as the glue cools.

Contrary to whats said about oil repelling water / asphaltum/ glue, the glue will bridge the asphaltum. Without cutting, you run the risk of chipping outside your masked areas.

[erik winkler]

Rod's right. Looks like you need to carefully re read the notes.

Go here: http://www.theletterheads.com/glawson/gluechip.html

read step 4. Temperature is listed in fahrenheit. Start with the maximum temperature, as lower temperatures, especially on larger pieces will produce an inconsistent chip as the glue cools.

Contrary to whats said about oil repelling water / asphaltum/ glue, the glue will bridge the asphaltum. Without cutting, you run the risk of chipping outside your masked areas.

Nope, I tattooed that text on my left arm, as well as the glue chipping book writen by Robert Mitchell.
I meant celcius (140 fahrenheit is 60 celcius).
What does bridge mean (the glue will bridge the asphaltum)? Do you mean when the glue runs from one sandlbasted area to another by running over the asphaltum? Because this happened allmost everywhere.

I applied the glue in an amount just enough to run a little, otherwise it would not flow at all and when it hit the asphaltum it just past it like there was no pasport control at the border.

Just can not figure it out what else I could be doing wrong.

It started chipping and it took chips of glass with asphaltum still stuck on it.
Pling pling sounds great, but when I look I can only use it for some stained glass ellements.
All the details are distroyed.

[Kent Smith]

Bridging is when the glue flows over the lines forming a "bridge".

Without being there, I would guess that the asphaltum you have is just not repelling well. Be sure that when you cut the glue that it stays cut and does not refuse which will cause it to chip that which you do not want. When pouring it is ok to control the flow, wipe off overflow (damp cloth) to minimize the effect of flowing over you limits then cut the gule.

[Larry White]

Might just make some sense to start over...........

[Patrick Mackle]

It could be the "Senefelders" asphaltum that you are using is the problem.
It is made for plate making, not glass etching and may not be pure asphaltum. The manufacturer may have added other materials
such as varnish or ingredients that result in making it less water repellent.
An asphaltum roof sealer, sometimes referred to as "wet patch" is pure asphaltum (avoid the wet patch with added glass fibers for thickening!) and may be a stronger repellent. I also found that Senefelders works poorly as a resist on glass for acid etching. It doesn't adhere well and begins to lift and float away under weak acid. If you are lucky enough to get it to stay for the first acid application, it will surely not make it for a second. Don't even imagine a third.
Pat

[erik winkler]

Thanks Kent, will cut it next time, but this time there was overflow everywhere. Allmost uncuttable in abundance.

Pat, This is something to work on.
I will go to the building supply store tomorrow and buy a cheap can of asfalt-roof-stuff.
Maybe three different brands
And let you guys know how it worked out.

Larry.... you are right, as allways. Everything here takes me at least five go's before it works

[erik winkler]

Asphaltum is sooooo 1900's!

Last few days I have made some experiments with alternative Asphaltum glue chipping.
I used a can of old roofbitumen we had hidden somewhere in our shop.
It was very thick and had some sandy substance in it. Like Pat said: Not good.

Today I went to the building shop and displayed all the roof-repairing cans next to each other.
A lot of them were elastic or rubbery, no good because it will not blast easily.
Others had filling components, like fibers, in them: Nog good, will prevent evenly blasting.
Some of them were extra thick pastes, which you had to apply on the roof with a metal scoop: No good.
I found one can which I thought could be workable.

Then I went to the waterresistant paints, that is the only thing needed: A layer which is extremely waterresistant, hold on the masking foil and is hard enough after drying so that it will blast away very quickly.
Did not find one today....

After that I went to the corner which contains brickwall waterreppelent liquids.
I found a transparant liquid, specially made for impregnating brick walls against (rain)water/moisture entering the walls/houses. This material can be removed with terpentine, so that's a product to try out.

Painted some glass samples with the new products, will keep you posted.

Erik

[erik winkler]

Here some photo's of the experimental chipping.
After resistant liquids are aplied and the glue has poored.

With the old roof repair bitumen, which contains sand and fibers, the blasting was way too deep.
But it poored relatively clean in the blasted 'valleys'. Will just have to wait how it will chip.

Bitumen with fibers and sand 1.JPG (92.86 KiB) Viewed 19502 times

Bitumen with fibers and sand 2.JPG (143.78 KiB) Viewed 19510 times

The clean bitumen substance was easy to brush/dip on with a piece of sponge.
Masking adhered good after 2 hours and blasting went fine. Pooring the glue went okay the first few drops.
But after giving it a good thickness it seeped over hte edge a little.

Bitumen 1.JPG (107.93 KiB) Viewed 19489 times

Bitumen 2.JPG (93.73 KiB) Viewed 19482 times

[erik winkler]

The water resistant clear wall protector was something special to work with.
Brushed/dipped it over the glass surface with a piece of sponge.
It flattened out by it self after letting it dry.
It dried hard after 1 hour.
Masking adhered good, but not as good as with the bitumen sample.
After extra squegeeing with a roller it blasted away fine and quickly.
Pooring the glue was amazing to see, it repelled like crazy!
But again after some extra drops to give it the proper thickness it flowed over the edges.
After the glue had gelled up a little I cut the bridges through.
Just have to see and wait how it will chip on these edges, but I have good hopes.
(The wavy rimples is a clear applicationtape on the back protecting the glass against scratching)

Water resistant clear 1 .JPG (63.32 KiB) Viewed 19508 times

Water resistant clear 2.JPG (48.79 KiB) Viewed 19490 times

[Patrick Mackle]

Erik,
I don't see that this test is going to chip like you may be hoping for. The glue will be locked in due to the depth of the etching and the deep "spine" layer of dried glue at the bottom of the carved design.
For animal glue to chip well, it must be a uniform thickness so that it will dry evenly and pull on itself.
Rather than squeeze bottle filling the etching, try experimenting with something like this.
Pour out a thinner (thinner layer of glue, not more water) evenly coated amount of glue onto the back side of a mirror. (the painted side) Place the mirror into a refrigerator until it jells to the point that you can roll up an edge and peel the "pancake" of glue off the painted surface. Use a knife to cut only the area you need from the pancake.
Place the jelled glue over the etched area and slowly warm it again (with a heat gun on low setting) so that the even layer of glue settles down into the etching. You will see the glue begin to "clear up" the frosted glass as it begins to adhere to the rough sandblast. Do not over heat the glue or it will melt too much and pool into the bottom of the etching.
The only other way to get a uniform layer of glue would be to spray it as a thinner mixture with several coatings. Each spray coat would have to be jelled it the refrig.
in order to build up a good even glue chipping layer.
After you have heated the pancaked layer or finished spraying the glue, you would have to allow it to dry just a little( 2-3 minutes or so) , then return it to to refrig to jell once again. (always allow it to only jell and NOT freeze). When it has jelled, use a new razor blade across the top of the asphaltum surface to shave off any glue that is on the asphalted surface. Thus leaving ONLY the even layer of glue within your deep etched areas.
If glue will be able to chip in finely carved deep designs, this method I have described is probably the best way to achieve it in any kind of acceptable manner.
This comes in part from an idea that I have entertained of selling prelayed uinform animal glue on a silicone sheet that could be computer cut and applied to complex designs requiring glue chipping in large production were hand application would too costly.
Pat

[Mike Jackson]

Erik,
You are already getting some good advice from Pat and the rest. My only quick observation is it looks like you are trying to put the glue on WAY TOO THICK!

To help you get the right idea, do a plain old sample of glass one foot square. Etch it to within maybe 1/2" all around. Then mix up the correct amount of glue for one square foot which is roughly 1.5 ounces of glue and 3 ounces of water by weight. Get your glass level and pour the entire mixture out on the glass and let it spread out on the glass evenly. THAT is the thickness of glue you need on your next pieces, even when poured through a bottle. We found it to be about the same thickness as our old Anchor Continental Sandblast Stencil.

Your photos show a thickness of roughly three times that, and with a lot of doming going on. Until you do the test above to learn the proper thickness, you'll run into a lot of problems.

M. Jackson

[erik winkler]

Pat, thanks for the mayor contribution!
Mike, good to hear from you.
I thought I had the right thickness... It is exactly the thickness I was learnt at the workshop.
Maybe my photo's are not very well taken. The size of the glass is only 5 x 5 inch, the complete scroll 4 inch high!
I think normally one would mica etch these tiny detailed scrolls, but I wanted to see what the minimum size for glue chipping would be.
And I never worked with the asphaltum method, so I thought in combining those wishes in these experiments.

So if I am correct in interpreting your good points, maybe it is the extreme small scale of the photo's and ornaments which shows these 'thick' glue blobs and round edges.
Here a few follow up photo's of the experiments that were up and running:

Here a 1 inch chip from the bitumen sample.
Note that the red outline shows how the glass was chipped along with the bitumen wich was on the glass outside the sandblasted surface.
Conclusion: Not perfectly water/glue repelent for extreme small detail chipping without cutting.

Bitumen.JPG (73.85 KiB) Viewed 19393 times

Here a 1,5 inch chip from the clear waterrepelent wall protector.
Note that the red outlines show how the glue chipped the glass, but absolutely did not attack the non-sandblasted parts which were still coated with the magic stuff.
Conclusion: Looks like the perfect water/glue repelent for extreme small detail chipping without cutting.

Waterrepelent clear.JPG (77.45 KiB) Viewed 19395 times

All comments are greatly appreciated!

Closing the doors for three days and off to Euro Disney Paris.
Erik

[Mark Summers]

Wonder if we can beat this dead horse again.
Here is the thing. I went to chip a glass and mixed a ratio (3 oz. Dixie cup)
of 1:1.25 (5x glue) and a week later and more and many sunlight sessions with a black background has left my chipping still not quite done. I read a
previous post 'glue chipping machine' with someone and my exact
problem. The problem I think is the ratio discussed numerous times
above. I am at 9000 ft. with way low humidity. As I would understand
my problem is a too thin a mix.
Glawson would say 1.5 water to 1.0 glue but I'm pretty sure that
would be that much more difficult. Many others had their ratios.
I'm guessing I will just have to just try my ratio at 1:1 and see
what happen. BTW I have Bob Mitchell's glue chip book and he
goes into weighing the glue.
If anbody wants to give some more input please do.

Mark

[Mike Jackson]

Hi Mark,
We've found that not all 5x glues are exactly the same. There's a variable worth mentioning.

The formula I remember is 1.5 oz of dry glue per square foot of coverage. That would be covering a piece of glass solid. In our glass with designs, it is much harder to estimate, but if you did a test on a solid square foot chunk of glass, you could at least see how thick the glue "should be".

The other part of the formula is/was 1:2 ratio of glue to water. As it turns out, water is twice as heavy as the dry glue. So, if you use a cup of glue, you can use a cup of water. By volume, it would be 1:1 but by weight it is 1:2.

Lastly, the amount of water used is only relatively important, as all water is evaporated out at the time it starts chipping. If you need the glue to flow out, you can add a little more water, and if you are squeezing the glue out of a bottle, you can add water, but always remember the thicker consistency glue will need to be applied thicker.

For the group of us in the Rocky Mountains, we get the benefit of low humidity on most days which helps with drying out the glue and getting good chips. 3-10% humidity is great. By contrast, people on the coasts often have to use drying booths to help reduce the humidity .

M. Jackson

[Roderick Treece]

The first time I saw glue chipping was at Rick's Shop and I think most people had theirs chipped overnight.The first time I was shown how to do it was at Yoders studio and we had it chipped in one long day in a booth.
My main observations now are
2 to 1 ratio
flow over the design
Don't put it on to thick 1/16 to 1/8"
Let it dry out with a fan blowing air across it slowly until it hard. This is maybe one of the most important things.
Then into the booth at 120 to 140o for overnight. It's almost always chipped by the next day.

In the case of altitude I know that really effects cooking .As for low humidity you wouldn't have to add dessicant dryiers like I do.

[Roderick Treece]

While doing an internet shearch for "Glue chipped glass signs" I found The 1997 signcraft article by Mike Jackson Step-by step; Glue chipped glass.I found it interesting that highlighted was this qoute,

"Asphaltum is the
“secret ingredient”
in this process."

While I understand where the notion comes from I for one do not use Asphaltum to do my glue chipping. I find it unnessasary and messy.

Roderick
www.customglasssigns.com

http://www.signcraft.com/Libraries/arch ... s-Sign.pdf

[Larry White]

Here's how I do it when I don't feel like using Asphaltum....

Anti-Chip1.jpg (61.44 KiB) Viewed 19073 times

Apply mask & weed.
Sandblast.
Level and flow glue over the whole thing.
Let gel, cut glue at mask edge.
Remove mask.
Allow to dry.
Subject to chipping environment.

Ain't rocket sceince Treece.



.

[Jerry Berg]

All that cutting around everything seems to me to be extra work, that could easily be avoided by the use of asphaltum.
At least on smaller pieces. On larger pieces like Larry shows cutting can save on applying the asphaltum, but on a larger piece that has a lot of detail would'nt that mean more unneccesary extra cutting? Maybe I'm wrong but it seems to be saving a lot of time using asphaltum vs. the extra job of cutting around everything? What is the advantage?

[Mark Summers]

Roderick,
2-1 ratio? By weight or volume? My first experience wasn't so
good and I'm guessing it would have finally chipped by 2012.

Mark

[Larry White]

If you don't use Asphaltum, you don't have to clean it off...or pay for it.

Flowing the glue over this piece, 1 minute.
Cutting the glue on this piece, 1/2 hour.

For this piece, applying and cleaning off Asphaltum, 1-1/2 hours. Carefully flowing in the glue, probably 1/2 hour.

Another perk to no Asphaltum, is there's no worry about the mask "blowing" when sandblasting.

A piece with intricate detail, I would use the Ashaltum method.

I would rather cut the glue, than clean off Asphaltum.

I, unlike Rod, remove the mask. ....still trying to figure out what that Treece method is exactly....



.

[Jerry Berg]

O.K., I'm seeing the light here. I'm going to have to find where that thread was explaining the spreading of all that glue evenly.... did you just spread the glue with a sqeegee or use a trowell? Seems like I remember a trowell. Asphaltum IS nasty to clean off.

Thanks!

[Larry White]

I calculate how much glue to mix up (3oz glue with 4-1/2oz water/sq.ft. of glass), heat it good and hot, then pour it over the glass surface, if it needs a little help covering the surface, I use a Glawson glue spreader. If the glass is level, it'll flow out to a uniform thickness.

The panel pictured actually belongs to one, Sally Jenco. I was assisting him in the production of this sign blank...for my nominal fee of two Satomi Super Signature Sets.

..I think he thinks the fee is only one Set....but, I got the glass!

Go on then!


.

[Roderick Treece]

One issue I have with pouring the glue right up to the edge of the design is sometimes it ends up to thin after it dries. If I go past and trim it then it seems to end up the right thickness to chip right.
Yes I think trimming is a pain but watching the glue chip for 8 to 10 hours makes up for that

I leave the mask on for two reasons 1 the glue come off easyier when triming it back and 2 if I do have to re chip my design is intact ready to go.
I like 1.5 oz dry glue per sqft of glass 1 part glue by weight to 2 part h2o by volume.

Larry , is that a piece of electric glass your chipping on there ?

I've tried the roller methoud without success so I just pour it on as hot as possible.

Roderick