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3D Printer Nozzle from Makergear M2 Scale Bar

$19.00 – $400.00

A large number of additive processes are available. The main differences between processes are in the way layers are deposited to create parts and in the materials that are used. Each method has its own advantages and drawbacks, which is why some companies offer a choice of powder and polymer for the material used to build the object.[40] Others sometimes use standard, off-the-shelf business paper as the build material to produce a durable prototype. The main considerations in choosing a machine are generally speed, costs of the 3D printer, of the printed prototype, choice and cost of the materials, and color capabilities.[41] Printers that work directly with metals are generally expensive. However less expensive printers can be used to make a mold, which is then used to make metal parts.[42]

Some methods melt or soften the material to produce the layers. In Fused filament fabrication, also known as Fused deposition modeling (FDM), the model or part is produced by extruding small beads or streams of material which harden immediately to form layers. A filament of thermoplastic, metal wire, or other material is fed into an extrusion nozzle head (3D printer extruder), which heats the material and turns the flow on and off. FDM is somewhat restricted in the variation of shapes that may be fabricated. Another technique fuses parts of the layer and then moves upward in the working area, adding another layer of granules and repeating the process until the piece has built up. This process uses the unfused media to support overhangs and thin walls in the part being produced, which reduces the need for temporary auxiliary supports for the piece.[43] Laser sintering techniques include selective laser sintering, with both metals and polymers, and direct metal laser sintering.[44] Selective laser meltingdoes not use sintering for the fusion of powder granules but will completely melt the powder using a high-energy laser to create fully dense materials in a layer-wise method that has mechanical properties similar to those of conventional manufactured metals. Electron beam melting is a similar type of additive manufacturing technology for metal parts (e.g. titanium alloys). EBM manufactures parts by melting metal powder layer by layer with an electron beam in a high vacuum.[45][46]Another method consists of an inkjet 3D printing system, which creates the model one layer at a time by spreading a layer of powder (plaster, or resins) and printing a binder in the cross-section of the part using an inkjet-like process. With laminated object manufacturing, thin layers are cut to shape and joined together.

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3D Printer Nozzle from Makergear M2 Clogged

$19.00 – $400.00

A large number of additive processes are available. The main differences between processes are in the way layers are deposited to create parts and in the materials that are used. Each method has its own advantages and drawbacks, which is why some companies offer a choice of powder and polymer for the material used to build the object.[40] Others sometimes use standard, off-the-shelf business paper as the build material to produce a durable prototype. The main considerations in choosing a machine are generally speed, costs of the 3D printer, of the printed prototype, choice and cost of the materials, and color capabilities.[41] Printers that work directly with metals are generally expensive. However less expensive printers can be used to make a mold, which is then used to make metal parts.[42]

Some methods melt or soften the material to produce the layers. In Fused filament fabrication, also known as Fused deposition modeling (FDM), the model or part is produced by extruding small beads or streams of material which harden immediately to form layers. A filament of thermoplastic, metal wire, or other material is fed into an extrusion nozzle head (3D printer extruder), which heats the material and turns the flow on and off. FDM is somewhat restricted in the variation of shapes that may be fabricated. Another technique fuses parts of the layer and then moves upward in the working area, adding another layer of granules and repeating the process until the piece has built up. This process uses the unfused media to support overhangs and thin walls in the part being produced, which reduces the need for temporary auxiliary supports for the piece.[43] Laser sintering techniques include selective laser sintering, with both metals and polymers, and direct metal laser sintering.[44] Selective laser meltingdoes not use sintering for the fusion of powder granules but will completely melt the powder using a high-energy laser to create fully dense materials in a layer-wise method that has mechanical properties similar to those of conventional manufactured metals. Electron beam melting is a similar type of additive manufacturing technology for metal parts (e.g. titanium alloys). EBM manufactures parts by melting metal powder layer by layer with an electron beam in a high vacuum.[45][46]Another method consists of an inkjet 3D printing system, which creates the model one layer at a time by spreading a layer of powder (plaster, or resins) and printing a binder in the cross-section of the part using an inkjet-like process. With laminated object manufacturing, thin layers are cut to shape and joined together.

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3D Printer Nozzle from Makergear M2

$19.00 – $400.00

A large number of additive processes are available. The main differences between processes are in the way layers are deposited to create parts and in the materials that are used. Each method has its own advantages and drawbacks, which is why some companies offer a choice of powder and polymer for the material used to build the object.[40] Others sometimes use standard, off-the-shelf business paper as the build material to produce a durable prototype. The main considerations in choosing a machine are generally speed, costs of the 3D printer, of the printed prototype, choice and cost of the materials, and color capabilities.[41] Printers that work directly with metals are generally expensive. However less expensive printers can be used to make a mold, which is then used to make metal parts.[42]

Some methods melt or soften the material to produce the layers. In Fused filament fabrication, also known as Fused deposition modeling (FDM), the model or part is produced by extruding small beads or streams of material which harden immediately to form layers. A filament of thermoplastic, metal wire, or other material is fed into an extrusion nozzle head (3D printer extruder), which heats the material and turns the flow on and off. FDM is somewhat restricted in the variation of shapes that may be fabricated. Another technique fuses parts of the layer and then moves upward in the working area, adding another layer of granules and repeating the process until the piece has built up. This process uses the unfused media to support overhangs and thin walls in the part being produced, which reduces the need for temporary auxiliary supports for the piece.[43] Laser sintering techniques include selective laser sintering, with both metals and polymers, and direct metal laser sintering.[44] Selective laser meltingdoes not use sintering for the fusion of powder granules but will completely melt the powder using a high-energy laser to create fully dense materials in a layer-wise method that has mechanical properties similar to those of conventional manufactured metals. Electron beam melting is a similar type of additive manufacturing technology for metal parts (e.g. titanium alloys). EBM manufactures parts by melting metal powder layer by layer with an electron beam in a high vacuum.[45][46]Another method consists of an inkjet 3D printing system, which creates the model one layer at a time by spreading a layer of powder (plaster, or resins) and printing a binder in the cross-section of the part using an inkjet-like process. With laminated object manufacturing, thin layers are cut to shape and joined together.

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Spider Fossil in Amber

$19.00 – $400.00

Amber is fossilized tree resin, which has been appreciated for its color and natural beauty since Neolithictimes.[2] Much valued from antiquity to the present as a gemstone, amber is made into a variety of decorative objects.[3] Amber is used in jewelry. It has also been used as a healing agent in folk medicine.

There are five classes of amber, defined on the basis of their chemical constituents. Because it originates as a soft, sticky tree resin, amber sometimes contains animal and plant material as inclusions.[4] Amber occurring in coal seams is also called resinite, and the term ambrite is applied to that found specifically within New Zealand coal seams.[5]

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Hawaiian Bobtail Squid Theme (Late Stage Development Eggs): Research by Dr. Spencer Nyholm

$19.00 – $400.00

The Nyholm lab studies beneficial host-microbe interactions between the Hawaiian bobtail squid, Euprymna scolopes, and the bioluminescent bacterium, Vibrio fischeri. Hawaiian bobtail squid are nocturnal predators, remaining buried under the sand during the day and coming out to hunt for shrimp at night neat coral reefs. The squid have a light organ on their underside that houses a colony of glowing bacteria (V. fischeri). The squid uses this bacterial bioluminescence in a form of camouflage called counter-illumination, masking it’s silhouette by matching moonlight and starlight; thus hiding from predators swimming below. The light organ is attached to the ink sac and it can use this ink like a type of shutter to control the amount of light. This likely helps the squid adjust to variable light conditions, for example cloudy nights or a full vs. new moon. In this image of a juvenile squid, you can clearly see the bi-lobed light organ and ink sac in the center of the squid’s mantle cavity. 

The Hawaiian bobtail squid lay their eggs in clutches on the sea floor, where they take approximately three weeks to develop. This series of macropod images allows us to see the developing squid and monitor embryogenesis. Once the squid hatch, V. fischeri from seawater colonize the light organ within hours. This macropod image allows us to see a close-up view of the ciliated appendage-like structure found on the surface of the juvenile squid’s light organ. Once the squid hatches, the cilia assist in bringing V. fischeri in the seawater to pores at the base of the light organ. These pores lead to inner crypts, where only V. fischeri can enter and colonize. V. fischeri is a relatively rare member of the seawater bacterial community, making up less than 0.1%. The Nyholm lab is trying to understand how the squid’s immune system can differentiate between the symbiont and all the other different kinds of bacteria in seawater.

While the light organ of the squid exemplifies a highly specific beneficial relationship between bacteria and host to provide camouflage at night, this organ is only found in some squid species. All squid, however, are capable of another type of camouflage, cryptic coloration. Squid skin contains special pigmented cells called chromatophores that can change the overall color of the squid in seconds. Each chromatophore contains pigment granules surrounded by nerve and muscle fibers. When these muscles are contracted, the pigment sac expands, creating a larger surface area of color. When the muscles relax, the pigment sac can shrink to a small dot, 15 times smaller than their expanded size, hiding the color. In these macropod images you can see relaxed chromatophores on the mantle and contracted chromatophores around the eyes. The macropod images allow us to see these pigment cells in great detail.

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Hawaiian Bobtail Squid Theme (Juvenile): Research by Dr. Spencer Nyholm

$19.00 – $400.00

The Nyholm lab studies beneficial host-microbe interactions between the Hawaiian bobtail squid, Euprymna scolopes, and the bioluminescent bacterium, Vibrio fischeri. Hawaiian bobtail squid are nocturnal predators, remaining buried under the sand during the day and coming out to hunt for shrimp at night neat coral reefs. The squid have a light organ on their underside that houses a colony of glowing bacteria (V. fischeri). The squid uses this bacterial bioluminescence in a form of camouflage called counter-illumination, masking it’s silhouette by matching moonlight and starlight; thus hiding from predators swimming below. The light organ is attached to the ink sac and it can use this ink like a type of shutter to control the amount of light. This likely helps the squid adjust to variable light conditions, for example cloudy nights or a full vs. new moon. In this image of a juvenile squid, you can clearly see the bi-lobed light organ and ink sac in the center of the squid’s mantle cavity. 

The Hawaiian bobtail squid lay their eggs in clutches on the sea floor, where they take approximately three weeks to develop. This series of macropod images allows us to see the developing squid and monitor embryogenesis. Once the squid hatch, V. fischeri from seawater colonize the light organ within hours. This macropod image allows us to see a close-up view of the ciliated appendage-like structure found on the surface of the juvenile squid’s light organ. Once the squid hatches, the cilia assist in bringing V. fischeri in the seawater to pores at the base of the light organ. These pores lead to inner crypts, where only V. fischeri can enter and colonize. V. fischeri is a relatively rare member of the seawater bacterial community, making up less than 0.1%. The Nyholm lab is trying to understand how the squid’s immune system can differentiate between the symbiont and all the other different kinds of bacteria in seawater.

While the light organ of the squid exemplifies a highly specific beneficial relationship between bacteria and host to provide camouflage at night, this organ is only found in some squid species. All squid, however, are capable of another type of camouflage, cryptic coloration. Squid skin contains special pigmented cells called chromatophores that can change the overall color of the squid in seconds. Each chromatophore contains pigment granules surrounded by nerve and muscle fibers. When these muscles are contracted, the pigment sac expands, creating a larger surface area of color. When the muscles relax, the pigment sac can shrink to a small dot, 15 times smaller than their expanded size, hiding the color. In these macropod images you can see relaxed chromatophores on the mantle and contracted chromatophores around the eyes. The macropod images allow us to see these pigment cells in great detail.

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Chert Madison type arrow point, mid-17th century, eastern New York, Cook Collection , UConn

$19.00 – $400.00

The bow and arrow represents one of the great technological advancements in weaponry in the ancient world. In fact, the bow is the first mechanical device that could store energy, as the arrow was held in the string before its release. Recent distance records in flight archery for pulled bows are around one third mile, the longest crossbow shot is 1.16 miles! Bows and arrows were used just about everywhere in the world except Australia where spear throwers were the preferred weapon. Triangular shaped arrow points were one of the most common types of arrow points used on the tips of arrows.

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Chert Madison type arrow point, mid-17th century, eastern New York, Cook Collection , UConn

$19.00 – $400.00

The bow and arrow represents one of the great technological advancements in weaponry in the ancient world. In fact, the bow is the first mechanical device that could store energy, as the arrow was held in the string before its release. Recent distance records in flight archery for pulled bows are around one third mile, the longest crossbow shot is 1.16 miles! Bows and arrows were used just about everywhere in the world except Australia where spear throwers were the preferred weapon. Triangular shaped arrow points were one of the most common types of arrow points used on the tips of arrows.

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Chert Madison type arrow point, mid-17th century, eastern New York, Cook Collection , UConn

$19.00 – $400.00

The bow and arrow represents one of the great technological advancements in weaponry in the ancient world. In fact, the bow is the first mechanical device that could store energy, as the arrow was held in the string before its release. Recent distance records in flight archery for pulled bows are around one third mile, the longest crossbow shot is 1.16 miles! Bows and arrows were used just about everywhere in the world except Australia where spear throwers were the preferred weapon. Triangular shaped arrow points were one of the most common types of arrow points used on the tips of arrows.

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Silver 1662 Oak Tree twopence, Hull Mint, Boston, from Windsor, CT

$19.00 – $400.00

The Willow Tree series was replaced because of a new technology. Rather than simply using the older hammer striking method Richard Doty has suggested Hull changed to a rocker arm press. The dies needed for a rocker arm press were quite different from dies used in the hammer strike method. A rocker press used large-sized rectangular shaped dies with a curved face so that the die could rock back and forth. The image for the coin was then engraved on the curved face of the rocker, one rocker for the obverse and another for the reverse (click here for picture of rocker dies). The two rocker dies would then be mounted face to face in the press. By pulling a lever the upper and lower rockers would press against each other with a rolling motion (click here for picture of a rocker press). As long as the two dies were properly aligned a blank planchet placed between them would be impressed with the design of the dies.

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Silver 1662 Oak Tree twopence, Hull Mint, Boston, from Windsor, CT

$19.00 – $400.00

The Willow Tree series was replaced because of a new technology. Rather than simply using the older hammer striking method Richard Doty has suggested Hull changed to a rocker arm press. The dies needed for a rocker arm press were quite different from dies used in the hammer strike method. A rocker press used large-sized rectangular shaped dies with a curved face so that the die could rock back and forth. The image for the coin was then engraved on the curved face of the rocker, one rocker for the obverse and another for the reverse (click here for picture of rocker dies). The two rocker dies would then be mounted face to face in the press. By pulling a lever the upper and lower rockers would press against each other with a rolling motion (click here for picture of a rocker press). As long as the two dies were properly aligned a blank planchet placed between them would be impressed with the design of the dies.

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Blue Iris

$19.00 – $400.00

Eyes are the organs of vision. They detect light and convert it into electro-chemical impulses in neurons. In higher organisms, the eye is a complex optical system which collects light from the surrounding environment, regulates its intensity through a diaphragm, focuses it through an adjustable assembly of lenses to form an image, converts this image into a set of electrical signals, and transmits these signals to the brain through complex neural pathways that connect the eye via the optic nerve to the visual cortex and other areas of the brain. Eyes with resolving power have come in ten fundamentally different forms, and 96% of animal species possess a complex optical system.  Image-resolving eyes are present in molluscs, chordates and arthropods.