| Posted: Tue Feb 20th, 2007 07:59 pm
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|Streuter Technologies: No Days Glaze Report
January 30th I was invited to visit Streuter Technologies,
manufacturer of the new No Days Glaze product, in San Clemente, CA.
Bart Streuter, owner and president of the company, spent 3 hours
answering my questions, showing examples of how this new glazing
material is used, and providing me samples to try it for myself.
I am very grateful for the time Mr. Streuter took out of his busy
schedule and devoted to me. I hope this report will be helpful to
No Days Glaze (hereinafter shortened to NDG) is a revolutionary
glazing product. It could very well replace traditional putty (or
cement for you purists) and how we construct leaded stained glass.
NDG has properties that may surpass the properties of traditional
putty in the structural system of stained glass construction, in its
long-term resistance to the elements, and in its long-term re-
workability in the instances of repair. I know that for many
experienced glaziers in the stained glass trade it will be quite a
leap to abandon centuries of tradition and venture into the unknown
reaches of this technological advance, but NDG, in my humble opinion,
is worth trying.
If NDG does find acceptance in the trade, it could also revolutionize
conservation practices and replace deteriorated putty. NDG has the
potential to outlast the lead came in which it is used without a loss
of its own properties. Product life testing is not complete, but
results thus far do indeed look promising.
Streuter Technologies develops and markets specialized "gaskets" to
the electronics industry. These "gaskets" are used between power
transistors or integrated circuits and heatsinks to provide excellent
thermal conduction (to keep junction temperatures at low levels,
which means the electronics last longer) while also providing
electrical insulation (to keep you from getting electrocuted). In
the normal physical world good thermal conductors, such as gold,
silver, copper, tin, lead, etc., are also excellent electrical
conductors. But there is a special class of organic materials
(some "plastics", if you will allow a generic term) that have good
heat conduction properties, but will not conduct electrons
(electricity). While this is not of particular interest to stained
glass artisans, the point is that Streuter Technologies is a solid
company, well versed in technology, and well respected in the
electronics industry. It is from this base that they look for
applications of their technology in other markets. One of their
chief engineers is a stained glass hobbyist, and it is he who
experimented, pioneered, and pointed the way to the introduction of
No Days Glaze.
The original product development, the "parent" of NDG, was a
formulation with adhesive properties to not only provide excellent
heat conduction and electrical isolation, but also to bond the
heatsink and fan to the Intel Microprocessors used in your computer.
It turned out that the adhesive bond was so strong that removal and
reuse of the heatsink/fan component from failed processors was a
problem. The product was re-formulated and is probably in your
computer today. But it was this property, along with several others,
that caught the attention of that chief engineer. With a series of
experiments and reformulations, No Days Glaze was born.
No Days Glaze Properties
NDG is a "phase change" material. In simple terms that means that it
has a constant set of properties over a very wide temperature range,
and then at one degree above that range it takes on a different set
of properties. It basically acts like two completely different
materials, depending on temperature. The phase change temperature of
NDG is 160°F. Below that temperature it is a solid, and above, it is
a viscous liquid (like molasses in January; very sticky and will flow
if you push it).
As a solid it is flexible, even down to –60°F. The Shore (or Mhos)
Hardness (a measure of its stiffness) and Young's Modulus (yield
strength, the point of deformation beyond which it will not return to
its original shape) have yet to be determined by testing. My non-
scientific assessment it that in terms of flexibility, hardness, and
yield strength, NDG's properties are near those of lead.
With properties similar to lead, you may reasonably question how it
will help support heavy glass in a soft, flexible lead matrix, which
is one of the functions of the much stiffer putty. The answer is in
the adhesive properties of NDG. In application, NDG, lead came, and
glass is heated to the phase change temperature of 160°F. When NDG
becomes a viscous liquid it wets and adheres to the lead came and
glass. This bond is strong enough (after the phase change when
cooled to a temperature below 160°F) that you will break the glass
before you break the bond. If you are mindful of glass breakage
issues, you can pick up and flip a panel before any solder joints are
completed. NDG by itself will hold the panel together. I have
lifted a 2'x2' panel by its edge with no joints soldered, and without
any ill effects. In larger panels with the weight of glass and
flexibility of NDG, the center will tend to sag as the panel is
lifted, and you could cause a break in a narrow length of glass.
This type of handling is not recommended, but it does serve to
demonstrate the structural properties of NDG.
Please note that NDG, like traditional putty, does not relieve any of
the considerations for structural reinforcement in large panels.
They will still sag, bow, telescope, or hinge, depending on the size
and/or design. While large unsupported panels will still fail with
collapse or broken glass, the one advantage of NDG over putty in
these cases is that the glass will not fall out of the lead came
matrix. You could view it as a more graceful failure, if there is
such a thing. This of course, assumes that the window was properly
constructed with NDG, that the phase change temperature was achieved,
and that the NDG wetted and adhered to the lead and glass. Without
this wetting and adhesion, NDG will not achieve the weatherproofing
or structural properties, and will serve no useful purpose.
The flexibility of NDG may actually be advantageous over traditional
putty in door panel applications. Working with the flexible lead
came it will provide more shock absorption when the door slams, than
will the stiffer putty. This is purely my opinion and has not been
tested. But it does seem reasonable to my thinking that in some
range of mild shock, NDG would outperform putty in preventing cracked
glass since it has more "give" than the stiffer putty.
NDG provides a weather tight seal that is impervious to natural
elements, as well as several unnatural elements. It does not absorb
moisture and water PH from base to acid has no effect. UV exposure
in life tests beyond 20 years has shown no degradation in material
properties. Streuter Technologies is continuing its testing program
with a goal of taking the life tests out to 100 years. They promise
to publish the test reports on their website when testing is
Thus far in their life test sequences, NDG has retained all of its
original properties with no degradation. NDG can be reheated to 160°
F where it becomes liquid, glass removed, reinserted, cooled below
160°F, and the panel is as good as the day it was built. Just think
of future repairs on NDG-built windows; no more dental picks to
scratch out old putty, just heat and wipe. It could change the way
repairs are done in the future.
I had an over 30 year career as an electronics engineer and scientist
and have conducted hundreds of environmental life tests. I will
honestly tell you that in no industry has anyone ever carried a life
test out to 100 years. In this throwaway age such a thing is unheard
of. Most life tests are designed to assess the financial liabilities
through a limited warranty period. If even presented to the public,
they are slicked up and presented as "reliability assurance". My hat
is off to Streuter Technologies in their unprecedented efforts to
compare the viability of their technology to the centuries of
experience we have with putty formulations in stained glass. Testing
can easily run to $100,000 per test, with a comprehensive test
program reaching the million-dollar range. It is a substantial
investment and shows the level of commitment they are making to our
industry. It also shows that they have a very strong belief in their
product. From my limited exposure to NDG, I think that belief is
justified. NDG just may be the "product of the century" in its
impact on stained glass.
One method is to cut the lead, then cut strips of NDG to put into the
lead channel. A more efficient method may be to lay the 6-ft length
of came on the bench, insert lengths of NDG in the channel on both
sides, then cut the came as in normal practice. (Today, NDG is
produced in 3-ft lengths, but they are tooling up to produce it in
While NDG has no adhesive to hold it in the channel, the strips seem
to stay put just from the friction-fit in the channel – if you have
ordered the right width of material.
The width of NDG you order should be the same as the channel height
in the lead came you are using. It is easy to get confused. If you
look at the list of NDG widths offered, they correspond to the most
common FACE widths of lead came. DO NOT ORDER BY LEAD CAME FACE
WIDTH! NDG must lay flat in the bottom of the lead came channel. It
is not designed to wrap around the edge of the glass like a strip of
copper foil. When heated to its liquid state, and the glass is
gently pushed into the came channel, the strip of NDG in the bottom
of the channel will ooze out around the edge of the glass and fill
the face of the channel. When applied properly, NDG will fill the
channel around the glass the same as traditional putty.
When you look at thin strips of NDG you will naturally define it in
terms of its "width". Lead came is naturally defined in terms of its
FACE "width". In lead came manufacturer's literature the channel is
defined in terms of its "height". The most common channel "height"
is 5/32" in the US. "High Heart" lead came most commonly has a
channel height of 9/64", but there are several other different
heights commonly stocked. This contradiction in terminology between
the different products is confusing. Order the NDG "width" that is
equal to the lead came channel "height" that you are using. If you
have never seen the channel height specified on the came you
purchased, measure it.
Currently, Streuter Technologies literature instructs you to order
the NDG width that corresponds to your lead came channel "width".
This adds to the confusion, since lead came is defined in terms of
face width and channel height. I brought this up in our meeting and
I hope Streuter Technologies makes the correction and further
clarifies their literature. If you look at the illustrations they
provide, terminology differences aside, it should become very clear
as to how NDG is put into the came channel and guide you to ordering
the correct width of product.
When you have the glass pieces in place on each side of the came with
NDG in the channel, gently heat along the length of came with a hot
air gun until the NDG melts and the pieces slide together into
finished position by lightly pushing on the edge of the glass.
Remove the heat and allow the joint to cool and solidify. This whole
process takes less than a minute.
Look at the joint. NDG should have oozed around the edge of the
glass and filled the channel. The glass should be stuck tight to the
lead came. If you did not achieve adhesion, or if you need to
reposition the glass, just reheat until the NDG becomes liquid. You
can reheat as many times as necessary. There is no degradation in
material properties through repeated phase change cycles. (This is
one of the technological marvels of phase change materials.)
If you are using a highly textured glass, such as ripple, or a very
thin hand blown glass, where there is a lot of channel space that
needs to be filled, just put two strips of NDG in the channel, so you
have more material to work with.
If you have excess material that oozes out onto the came or face of
the glass, just reheat and wipe with a rag. It will clean right
off. You can also cut and scrape with a hobby knife, but heating and
wiping is easier.
To get good adhesion to the glass, the glass should be cleaned prior
to assembly to remove cutting oil, finger oils, or any other dirt
that would interfere with wetting and adhesion.
For heating, a hot air gun such as a hair dryer or one of those paint
removal air guns from the hardware store works very well. I bought
one at a Harbor Freight Tools ½ price sale for $10. You could also
use a quartz heat lamp, such as a Smith-Victor TL2, available at
photo supply shops (I saw one on ebay for $35), but they are
considerably more expensive than the hot air guns.
Continue the process of fitting pieces and heating to melt them
together until the panel is assembled. Now solder all your lead came
joints. Yes, the NDG will liquefy under joint being soldered, but it
will not interfere; it will not boil up in the solder nor will it run
out on the backside. Remember that NDG is very viscous, that is, it
is a very thick liquid in its liquid phase and tends to stay put
unless you push it. Once you've soldered your joints and cleaned the
panel, you're done.
There are many of you who lack the patience to let a natural satin
black patina develop on the lead came and solder joints over a
several year period. Or there may be a personal preference for that
black sheen achieved through the vigorous scrubbing with whiting
powder and a stiff natural bristle brush in the clean-up process with
traditional putty. And I will admit that that scrubbing process also
cleans up the rub marks on lead came that results from its handling.
Well, you can still sprinkle on the whiting and scrub away. It will
not affect NDG, even if you add a little traditional putty to get the
oil and lamp black that may well be contributing factors to that
black sheen. For those of you that like to use or finish with the
Pzazz brushing wheel and Carnauba wax to achieve an even higher
gloss, you can still do that. It will not affect NDG.
If you are using brass or copper came and applying patina to blend in
the solder joints, if you are using black patina on lead-free came to
achieve a more traditional appearance, or if you are one of the few
who use black patina on lead came, have no fear. Patina will not
affect NDG. Streuter Technologies has tested NDG with most of the
chemicals we use in the stained glass industry, such as glass
cleaners, fluxes, patinas, etc., and have found that NDG in
impervious to all of them.
That is my report on No Days Glaze. I suggest that you contact them
at http://www.streuter.com/stainedglass or 888-989-3832 and request samples
of NDG for your own trials or to ask any questions that I may have
overlooked in my own exploration. You can order No Days Glaze direct
from Streuter Technologies, or purchase it from Delphi Glass, in
Lansing, MI. Delphi is the first distributor to stock NDG. The rest
of our wholesale distributor network has adopted a wait-and-see
--Joseph 2bears, Lomita, CA
| Posted: Thu Apr 3rd, 2008 09:39 pm
|Joined: ||Thu Jan 17th, 2008|
|Location: ||New York USA|
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|OK, I went to their site and watched the assembly video. Here are 2 questions...
If the product liquifies with heat, and the stained glass panel is in direct sun most of the day, as the glass in the panel heats up will this product start to liquify an run?
Also will it allow for expansion and contraction the same way putty will?
I do see that if a client asked for stained glass in an Insulated Unit that this may have a use with out off gassing or leaving oily finger prints and whiting dust.
Has anyone out there used it?
| Posted: Tue Apr 8th, 2008 09:20 pm
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|Hi Hallie. Yes, I have built a panel with NDG, so I have some limited experience in working with it. If you will email me at firstname.lastname@example.org I will send you a user's report on my experience. I have not posted the report since I am in the process of publishing it in Glass Craftsman magazine. I just returned from Expo in Las Vegas where I talked to Joe Porcelli and Bart Streuter about my article. Bart Streuter is currently reviewing the report for comments which will be included in a sidebar to my report. I am not sure I made the best choices in using NDG, or used the best methods. That is why I have solicited Bart's feedback to be included with my report. As an example, I tend to solder hot and fast with a heavy Hexagon iron. This caused the NDG to boil out of the joint and cause a mess which was difficult to clean. A lower temperature iron might give better results. Aside from my clumsiness, I raise a number of issues in working with NDG that you will find insightful and helpful. I will be happy to send you a pre-publication copy if you will respect it as copyrighted material until it is published.
NDG is a "phase change" material. That is, below 160 °F it is a solid and at, and above 160 °F it is a liquid. As long as the window stays below 160, NDG will be a solid and will support the window. Normal solar heating should not be a problem.
NDG is a flexible material with excellent adhesive and sealing properties. It is not hard and brittle, and will flex to some degree. It is also impervious to almost everything and does not degrade over time. It has the promise of far outlasting the lead came. But as to how it performs in a window over decades we don't know. It is just too new. Streuter has performed weather tests and other strength tests with good results, but until there is long term installation experience the jury will be out.
I also agree with your thought that the best application of NDG may be in a triple-glazed Insulated Glass unit. But there are caveats to even that application which are covered in my report.
| Posted: Thu Apr 10th, 2008 02:12 am
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|I recently used NDG on a panel just to try it out. I used a heat gun for softening the material and slightly set the glass into the channel. When I was paying total attention, you could see the NDG change from solid to liquid. However if I was not totally attuned, I found the NDG would push out and travel further onto the glass than I desired. This overflow makes the job look dirty. As I tried to clean the NDG of the glass, I found no glass cleaner able to remove the overflow. I even resorted to a razor blade to scrap the excess. Finally, I stumbled upon WD40, of all things, and it cleaned the excess off the glass and then hit it with glass cleaner to remove the WD40 residue. Unfortunalely I did notice that the bond of NDG and the glass had deteriorated. I could, in spots, actually finger peel the NDG away from some glass. I probably did allot of things wrong but this was my first experience with NDG. Overall, it saves allot of time and you really need to pay attention in its heating application and is sweet to use if you pay attention. I plan on using it again but with the WD40..!!
| Posted: Fri Jan 17th, 2014 09:22 pm
Non AGG Member
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i have been doing stained glass for only 3 or 4 years and to this point have predominantly used copper foil. i have tended to avoid lead came because of the procedure, [perhaps due to my perconception-misconception- that it is too messy and tedious a process]
i just became aware of the no days glaze process and am reviewing your 2007 review as well as comments
7 years later [now]:any additional thoughts?
i like the idea of exploring some of my designs in lead came, and am wondering if the no daze glaze might be a viable option?
since i have COPD lung issues, this process would seem to reduce the amount of soldering required and putty dust generated.
thanks for your insights into stained glass
| Posted: Mon Jan 20th, 2014 07:17 pm
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|Don, sorry for the delay in getting back to you. I am posting the No Day's Glaze user report that I wrote from my experience with this product, and hoped to get published in the now defunct Glass Craftsman magazine with a sidebar comment from Streuter Technologies. I talked to both Bart Streuter and Joe Porcelli about this and provided copies of my report to both, but it died there. The following is entirely the experience and opinion of Joseph 2bears, The American Glass Guild bears no responsibility, nor does it endorse or necessarily agree with the report. I do hope you and others find it helpful.
No Days Glaze: One User’s Report
A recently completed a 5’x3’ Art Nouveau transom was my first use of No Days Glaze. For the most part the claims made for this product were accurate. It seems to be well suited for small panels that hang behind an existing window, but if you are a small or mid-size studio constructing larger windows to be installed in existing framing, you may want to consider my experience.
I did not realize three of the advertised benefits: “Superior Sealing”, “No Turning Over”, and “No Mess”. The implied time savings from the fast cure (the “Cures in Seconds” claim is accurate) was another benefit I did not realize. I spent time equivalent to the curing time of traditional putty cleaning excess NDG off the panel.
I will simply tell you what I did, and let you judge my methods and results.
Design and Application Decisions
My design used English Muffle glass and flat H-came in 9/32” and 3/8” face widths. I knew from researching the product that NDG was produced in 0.030” thick ribbons and all my came channel heights were 5/32”. I recognized that a 0.030”x5/32” ribbon represented a fixed volume of material, and I wondered how that would fill in under the leaf of the came, particularly when I was using two different face widths.
I called Bart Streuter and he informed me that their decision on the dimensions of the NDG ribbon was based on a 3/16” face came with a 3/16” channel height and 1/8” thick glass. When the NDG was heated to its melting point, and the glass pushed in to the came channel, the volume of NDG material would completely fill under the leaf of the came.
I also discussed the three suggested methods of assembly, “Hobby Cure”, “Quick Cure”, and “Professional Cure”, with Bart Streuter. The Hobby Cure method, where each piece of glass is heated and seated into the came individually, is the only method which will get the NDG to flow out under the leaf of the came and potentially result in a complete fill like traditional putty. The other two methods, in which the glass is cut 1/32” undersized to allow for the NDG ribbon thickness, results in a seal from the edge of the glass to the heart of the came. The area under the came leaf is left unfilled and open.
Leaving the area under the came leaf open and unfilled creates a trap for dirt and water, and sets up the conditions for rapid corrosion of the lead came, particularly in a window exposed to the elements. Even in interior installations there is a trap for dirt and window cleaning solutions, which set up the same corrosion conditions, albeit at a less accelerated pace than windows exposed to the outside environment. For these reasons I question the use of either the Quick Cure or Professional Cure methods of assembly for exposed windows, indoors or outdoors.
I chose to use the Hobby Cure method of assembly and try to get a complete fill under the leaf of the came. I chose to use a single ribbon of NDG in the 9/32” came. The Wissmach English Muffle glass is quite uniform in thickness and the fill volume appeared to be equivalent to Streuter’s volume analysis to determine product dimensions.
Two ribbons of NDG would be needed to completely fill under the 3/8” came leaf. But the volume of two ribbons would overfill and I would have some ooze out onto the glass to clean up.
I discussed clean up methods with Bart Streuter, since I knew that NDG was impervious to all commonly used glass cleaners and solvents. NDG can be trimmed and scraped with a hobby knife (a very tedious prospect), or as Bart suggested, the NDG can be heated to its melting point with the hot air gun and wiped away with a rag. The unfortunate thing is that either cleaning method still leaves a film, or haze, of NDG on the glass. No final solution for cleaning the film haze was suggested.
Now all of this volume analysis and under-leaf-fill is fine in theory, but in practice there are irregularities in glass cutting, the variability in hand-made glass thickness, glass texture, and variability in shaping lead came to surround the glass. The gaps to be filled are not a constant volume, but NDG is a constant-volume product. The only way to ensure a complete fill is to overfill and suffer the cleanup consequences. This is where I find fault with the “Superior Sealing” claim. In my opinion sealing involves not only edge-of-glass to came heart, but also face-of-glass to came leaf, leaving no voids for dirt or moisture entrapment in panels exposed to the environment. In this regard I think traditional putty is still the superior choice. It will completely fill and seal the variable volumes encountered in stained glass work.
For non-exposed panels, such as those being triple-glazed into an Insulated Glass Unit where traditional putty is not recommended, NDG may be a superior alternative. In that case, the under leaf fill is not a critical concern.
The cost of NDG used in this project was roughly $0.85 per foot, or $1.70 per foot for both sides of the came heart. I did not find any on-line or quantity discounts. Prices from several distributors were all within a few cents per foot.
By comparison, the cost for traditional pre-mix putty and whiting powder is less than $0.05 per foot for both sides of the came. There are volume purchase discounts on these materials, which can bring the price down to less than $0.02 per foot of came. And if you buy the raw materials and mix your own putty the cost can be reduced to less than $0.01 per foot.
Material cost for NDG can be a significant factor, particularly in larger panels. It can easily add over $100 to the cost of materials for a project several square feet in size. Since the client does not care about glazing materials, this additional cost comes out of the profit margin, and may eliminate any profit margin in competition with another studio using traditional putty.
I decided to go ahead and use NDG because I wanted to gain the experience in actually building a window with it, and because I think it is of potential benefit when having to triple-glaze a leaded panel into an Insulated Glass Unit. I made no profit on this job.
I assembled the panel using the Hobby Cure method as demonstrated in the video on Streuter’s website (http://www.streuter.com). There were a few things I noted that were more difficult than in traditional methods of work. First, deep curves, or “C” shapes do not fit together with the NDG ribbon in the channel. The NDG has to be melted before these shapes will slide into place. But in heating, the NDG tends to shrink into a string of blobs with blank spaces in between the blobs, before the center of the deep curve could be slipped into the came.
The second difficulty was in controlling the application of heat. If the NDG gets too hot, it tends to run out of the channel onto the lay-up board beneath the panel. And if the fixed volume of NDG is running out onto the lay-up board, there won’t be enough volume of material left to form the required seal. This was especially problematic for the deep curves or “C” shapes. Those blobs that formed quickly, tended to run out of the channel before I could get the glass in place to “smush” them out along the heart of the came and under the leaf.
Perhaps these problems are due to a lack of skill in working with NDG. With sufficient practice they may be overcome. One must become a “maestro” with the hot air gun and carefully develop a heating strategy for curved pieces so the interfering ends are brought to melt temperature before the open middle sections reach that point.
The third difficulty was when I discovered that I should have put a particular piece in before other pieces were placed. In traditional work I just pull a few pins, partially disassemble that section, put the piece that should have been placed first in position, and slide the came and other glass pieces back into place. It only takes a few seconds and is very easy to do. In the case of using NDG with the Hobby Cure method, it is not nearly as easy. The whole section has to be heated to the melt point to take it apart. The NDG tends to smear on the glass and in the came channel as it is removed. If the glass is set down on the lay-up board, then some of the NDG is smeared on the board. If the NDG solidifies before the glass is repositioned, then the glass becomes one with the board and has to be re-melted to free it. If the NDG solidifies in the channel while the glass is out, the glass will not fit back into the channel until the NDG is re-melted. And in all of this, it is quite easy to overheat and get some of the NDG to run out of the channel. In short, it is a messy process and sealing integrity is compromised because of the volume of NDG lost in the process.
My limited experience in rework suggests that the proper procedure should be to clean the NDG off the glass pieces, discard the lead came with NDG melted in the channel, cut new lead and start over. That would ensure that pieces would fit together as well as they did originally, and there would be a sufficient volume of new NDG to form a proper seal.
Of course, avoiding the need for rework is the best and most obvious solution. But this necessitates a higher level of assembly planning. I normally build a rectangular panel from one corner out to the opposite corner with two right angle guides for the perimeter to ensure the panel is square. This particular design would have necessitated building the panel from the center out to the perimeter to avoid repositioning in the assembly process.
The fourth difficulty I encountered is that it is not practical to tuck leads with the Hobby Cure method of assembly. Tucking lead is a practice in flat-face lead assembly where the leaf of the came is lifted and an intersecting came is “tucked” under the leaf of the running came. The lifted leaf is hammered down on the tucked came to form a tight joint. After the joint is soldered, it has no difference in appearance to the simple butt joint used in round head came construction. Those few who teach this method of construction believe that it results in a stronger joint. If this is how you were taught and is your preferred method of construction, then you are going to have difficulty with NDG.
Once the came leaf is glued to the piece of glass where you need to tuck a lead, that leaf is not going to lift without heating and melting the NDG. It is not impossible, but I think it is impractical. If the lead to be tucked is not heated, the NDG will solidify before tucking is achieved. Heating the came with NDG in the channel may cause it to blob and run out. And hot NDG on the end of your fingers is not pleasant. In the Quick Cure and Professional Cure methods of assembly, tucking of leads would not be a problem, since the NDG is not melted to form a seal until the entire panel is assembled.
The fifth difficulty I encountered was in soldering the joints. When I soldered the topside of the panel, the soldering temperature caused the NDG to liquefy and run out on the lay-up board under the joint. When I flipped the panel to solder the backside, the pattern came with it, glued to the panel at nearly every joint. It was necessary to clean these joints before I could solder.
I warmed each joint with the hot air gun and wiped the paper and NDG away with cotton rags. Old T-shirts torn into 3” squares are very good for this. Once wiped clean I was able to flux and solder the joints on the backside without difficulty.
Overall, assembly with NDG using the Hobby Cure method took twice as long as it would normally take with traditional methods to reach this point in construction.
Once the panel was soldered it was washed with dish detergent to remove the flux residue. This, of course, had no effect on the NDG smears, ooze outs, and run outs in the joint corners.
I tried trimming with a hobby knife and scraping it off the surface of the glass, but this was quite tedious and time consuming. I quickly abandoned this method of cleaning in favor of the suggested heat gun method. Heating and wiping with scraps of cotton rags went fairly well, but it took two days to do both sides of the panel. This was work that I would not have to do with traditional putty. And when it was done, I still had a thin film, or haze, of NDG on the glass on both sides of the panel.
Since NDG is impervious to solvents, the only way to remove the thin film haze is with abrasive methods. I discovered that whiting powder and a brush – yes, the same ones used with traditional putty – are very effective in removing the film. However, it does take about twice the scrubbing effort that traditional putty cleanup requires, but it does work. I spent another day scrubbing with whiting.
I finally ended up scraping out all of the joint corners with a hobby knife to get them clean and sharp. That took another day of effort.
All in all, I added 5 days to the normal construction time that I would have spent if I had used traditional putty. Four of those days were just to clean up the mess.
And I am exceedingly grateful that I did not have any highly textured glass in my first trial. I am not sure what I would have done if I had a ripple, reed, or fibroid glass to clean. This is certainly something to think about in a decision to use NDG the way I used it.
After washing the flux and hot wiping the excess NDG, the lead came was shiny with little scratches that develop from working it on the bench. In my opinion it looked unfinished. That would disappear in a few years as the lead oxidizes and forms its satin black patina, but I am used to the dark gray satin patina that forms when scrubbing traditional putty with whiting powder. That process takes a fair degree of scrubbing, but it removes the shine and surface scratches and gives the lead a head start on developing the satin black patina we prize so highly in stained glass work.
I tried brushing the lead with #0000 steel wool and a brass brush. Both removed the surface scratches and replaced them with a fresh lead satin sheen, but not the dark gray traditional methods produce. Scrubbing with copper or brass wool or a Pzazz brush also may be good alternative methods.
Finally, I tried scrubbing with my old whiting brush. I was very satisfied with the traditional patina it produced, and this is when I discovered that this very mild abrasive was enough to remove the NDG film, although it did take more scrubbing than traditional putty clean up.
If you are building a panel with NDG that will be triple-glazed into an Insulated Glass Unit and using one of the above methods to put a nice patina on the lead came, be aware that all of these methods produce dust that is anathema to sealed units. This dust will collect in any void under the leaf of the came, will fall out after the window is installed, will collect and be unsightly inside the sealed unit, and will ultimately result in replacement to placate a dissatisfied client. A very careful and thorough vacuuming to remove all dust from the panel is required. It may also be judicious to make a final pass with the hot air gun to re-melt the NDG to trap any remaining dust particles. Carefully wiping the lead with Stove Black may be an alternative method to scrubbing.
Summary and Conclusions
The material cost of NDG is considerably higher than traditional putty. It is difficult to achieve an under leaf seal with a constant volume product in a variable volume process. The labor content of the Hobby Cure method is greater than traditional methods, and the final lead appearance is an issue without a good resolution.
The obvious question to ask is, “Would you use No Days Glaze in another project?” My answer may surprise you. Yes, I would use it again! But I will qualify that answer by saying that I will be very careful in selecting the applications where it may be a suitable alternative to traditional methods.
Joseph 2bears Art Glass Studio
25029 Feijoa Ave
Lomita, CA 90717-2108
| Posted: Wed Jan 22nd, 2014 03:46 pm
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|Joseph: Anyone interested in furthering their knowledge about the craft owes you a huge "Thank You!" Your test run and diligent note-taking are the sort of testing many products should be subjected to but which many of us (me, for example) would rather not take the time and expense to perform.
It's also a testament to your use of the scientific method and quest for personal knowledge that you note the good & the dubious and sum up with a fair evaluation in the end.
Thanks for sharing - Tod