Rev. ... 2002-08-10, 2003-03-01, -08-15,
-09-06, 2006-04-02, -06-26, 2008-04-29,
2009-03-04, 2010-02-11, 2011-01-01
[Search on date pattern to find latest changes, more than one may be found.]
Working Glass Outdoors and keeping equipment there.
I mostly blow glass in my backyard (although I appreciate the kindness of several studios in the area that let me blow there occasionally.) My "studio" has a roof to keep rain from drowning the equipment. I work under the sky, using a sunshade when the sun is especially hot. On this page are pictures of my equipment with comments on building it, links to more detailed discussions and comments about using equipment exposed to the weather and great changes in temperature and also about working outdoors in various wind conditions and temperatures. |
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Bench | Annealer | Glory Hole | Burner | Tools | ||
Outdoor Working: | BUGS | MOSQUITOES | RAIN | TEMPERATURE | GROUND CONDITIONS | LIGHTING |
ELECTRIC | SUN | RAIN SHIELD |
Foundry | Mike Firth Glass | Tool Making |
At left is a plan, pretty much to scale, of my backyard with identifying
letters used below. H - house, driveway to top, street off left G - Garage/Shop AC - Air Conditioner compressor A - Rain shield for small forging, etc. B - Brick U BBQ unit C - Wood frame lean-to cover for annealers D - Metal frame concrete pad for furnace/glory b - bench m - marver c - wet tank on stool, bucket below a - 3rd arm f - tall fixture for area light Diagonal line at bottom is lot line (lot is parallelogram). Other side lot line is about 10 feet up from top edge (lot is 50' wide) Alley is about 30' beyond right edge. Large gate in fence gives access to narrow paved alley. |
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BENCH - I have back problems and, in fact, stand most of the day at my work. Getting up and sitting down repeatedly bothers my back much more than standing. I can and repeatedly do work glass from a regular bench when visiting shops, but when I began thinking about making a bench, the idea of standing up and a sketch of an ancient standing bench (with the marver slanted over head) encouraged me to work out the bench shown here. (Image below from Harvey Littleton's book, a Search for Form.) | |
a above | |
Among the details in the drawing are that the arms are L
shaped with the edge up, which tends to shed any glass drips or other
interruptions to rolling - flat topped arms are commonly used on sit-down
benches. A metal tab sticks up on the end of the arm to keep a pipe from
rolling off if I walk away briefly. The arms are much shorter than on a
sit-down bench as they don't have to reach past my body from the back rest
or allow for the elbow to palm distance there. The cross bar at the top,
besides being structural, is drilled for 1/4" carriage bolts that allow
hanging tools at eye level. The cross bars several inches up from the
ground fit my plan of being able to lift my equipment but are also L shaped
to take a shelf or blocks of weight. Hinging the marver (next) allows quick
removal as its pivot is just a longer end piece set inside the uprights.
2011-01-01 |
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Notice that the marver (m) is hinged at one end and tools are hung up on the rail on pegs which are just 1/4" carriage bolts (which have large round heads. (well, that doesn't show well in the picture right, a shield is hanging from the rail, top right.) The bucket of wet wood, once kept on the platform, now sits on a waist high stand after I kept getting the marver wet. To the right is a third rail (above), on a separate stand that holds the end of the punty while I am attaching it. The length of the rails is based on how far my arm will stretch when I stand and reach (I could make them longer and step forward while rolling the pipe, but I didn't.) A pipe hanger is located at the top right corner (see above.) Between the picture above and the one right, the plywood panel was replaced. On the plywood right, the white mass is frax in a Corningware bowl that is a catcher for ornaments while the loop is added to the top. The round tubes are for making marbles. |
ANNEALER - This is my annealer which is small but meets my
needs so far. (I am working on one in a refrigerator shell.) It
is a 24 x 30 inch box with 6 inch thick lid. When first built, it
had 6" of frax insulation all the way around and a 12 amp
120 volt element (Kanthal from Dudley Giberson) would take it to
fusing temperature (1550F) albeit slowly. The insulation took
exactly one roll (50 board feet 2" x 24" x 12.5') and
was designed that way. Since then I have taken out part of the
inner layer from the walls (so now 4" on the sides) and use
it just for annealing since fusing is not of great interest to me.
Recently the element was broken (by dropping molten aluminum on
it, if you must know) and I installed the new element on the lid
rather than on the walls to give me more space to lean pieces
against the wall. 5/1/2000 The stand has wheels at one end (hidden by the white bucket on the left) and the white shelf to the right also serves as a handle for moving. Resting on the shelf are the controller covered by a Plexiglas cover I made. The controller came from Love Controls and is a single ramp, self-learning controller that cost about $200 and is about 2" x 2" x 4".
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The lid is counter balanced with a concrete block hanging from an eye-bolt on an extension of the lid handle. I do not like springs which have to be carefully placed to balance the lid in most positions. By using an eyebolt down from the handle, the block swings under the lid, close to the annealer, being almost neutral at the lowest position. The lid actually has no hinges, resting when open on the shelf shown at the back. The weight can be unhooked and the lid lifted off at any time. Actually a light chain prevents the lid from flipping too far open from its own momentum. The 1x2" wood handle is fixed to the lid with 2"x1/4" bolts that were installed from the inside, through fender washers, when the lid was made. 5/6/2000 | |
In this shot (click to
enlarge) the parts of the annealer are well shown. The bar with
the block handing from the eyebolt. Notice that the L shaped
catch rail shown in the drawing is not in the photo. It was taken
off when the new steel frame was made and I have not installed
anything new. I don't trust the lid to just gravity (there are
not hinges, so I can lift the lid off fairly quickly when I need
to.) Visible as a dark diagonal line at the back is the chain that keep the lid from flopping over. The loop just at the pivot is a ground wire tying the lid to the body. The tan running through it is the power to the element in the lid. The black blob against the white insulation is the socket for a small (7-15 watt) light bulb that goes on with the element. The white panels on the end are explained below. |
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This is a shot
of the annealer open showing the connections for the first
element on the end, and the second element pinned to the lid. At
the present time the first element is broken and has the broken
ends hooked together, having a higher resistance and thus not
getting the box up to 900F. The wire of the first element is held
away from the metal box by the pieces of cement board/asbestos
shingle that show white and connections are made to brass bolts
mounted on the shingle. Normally, the connections are covered
with a heavy wire screen to keep fingers off of them. The upper
element has its leads passed through a chunk of insulating
castable, not a best choice because it has never been fired and
picks up moisture from the air; a chuck of insulating fire brick
or broken fired castable would have been a better choice. The frame below is the new welded one, from 1/2" square tubing, not yet painted and without wheels. It replaces one shown in some other pictures made of wood that lasted for about 9 years. 2001-06-07
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GLORY HOLE - The glory hole I use is
the second construction (see Hot Glass
Bits for discussions of early efforts) and it is perfectly
standard: a 30 gallon drum, lined with insulating board glued to
the walls then lined with insulating castable. The only unusual
construction choice is that rather than cutting the barrel
shorter and rewelding a rim, the depth of the hole was set by
pouring a mix of vermiculite and water glass in the bottom to
about 6" and then pouring a layer of castable on the
stiffened mix. Thus the bottom/back was well insulated and the
depth of the hole is not so great as to waste heat. The other oddity is the flat pot you can see through the door, called a boat by some, which is made from a formula gotten from Independent Glassblower #11 and reprinted and explored in my notes on making crucibles. |
FURNACE - Notes and furnace under construction furnaces.htm |
DOORS - The doors above and below show my
preference in doors - cheap, light and well balanced with long
handles well guarded from the heat. The wheels are at the bottom,
made from cast pulleys with a bronze bushing inserted. A guide/guard
rail keeps the door from flopping back or running off the ends.
The track is adjusted in and out to place the door so it will
lean against the opening lightly. When the handle is grasped, and
it is in the "shadow" of the door so it does not heat
up and can be grasped bare handed, the door naturally comes back
from the opening and is balanced on the wheels, being very easy
to move. The door below, cast in a pie pan, is not a good choice, because the castable cracks across the bolt lines. It should have been cast in a band of steel with a bolt adjustment for tightening, [Which was done with its replacement, here] (The unit on top of the furnace is a 1000 watt heating element set in a groove in a block of castable that is used for drying out and preheating the glory hole and furnace when they have not been used for some time in wet weather.) See doors.htm |
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BURNER - This is a perfectly standard burner arrangement that might have been built from the drawing in any of several books. The blower is the one Dudley Giberson suggests from Grainger Industrial Supply. One odd point is the air valve, which is built from wood with a sliding section. The grey 2"PVC pipe is glued to the wood but not to the white PVC reducer. (I use the blowers on other devices, include metal melting.) The pipe is 1 1/2" black iron with the flare piece at the end being 1.5" to 2" (about 2.75" OD) for swirl and flame retention. (The galvanized coating shown burned off the first time it was used, the piece in the picture being a repair.) The gas feed is high pressure (pounds, not ounces) and is fed to a brass tube with a treaded cap center drilled with a small hole. The tube is fitted through a drilled out brass reducer bushing so it can be adjusted to work fairly well - sucking enough air - if the blower is not on, giving a sort of fail safe operation. Burner Building Glory Hole |
TOOLS - While it may be useful and pleasant to have several hundred dollars in tools at hand when working glass, it is not necessary and most glass workers have one or more tools that is really cheap but handy and useful. Ironically, now that I see this picture on the screen, the most heavily used tool and most homemade is not in the picture - I made my own jacks.
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OUTDOOR GLASS WORKING - My equipment is
outdoors, which leads to certain problems. Some of these problems
apply to any studio that is somewhat exposed to the outdoors,
such as Art Allison's enclosed, but unheated (except by the
furnace!) place.
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