This page contains pictures and information regarding the various tip designs we have implemented over the past years.

Material: 308L Stainless
Slot Cut: .010" slotting saw
Price: $200-$400
Spot size: 100um - 250um

Hand tooled by Bill Sabala at the Stanford MechE department. This variety of tip was the mainstay of our printing operation for the last two years. All of our published arrays 1996-1997, including the yeast genome, were printed with this type of tip.
Material: 308L Stainless
Slot Cut: .010" slotting saw
Price: really expensive
Spot size: 100um - 250um

Another Sabala Special. This tip is adjustable via two opposing set screws. (Visibile on the top side). This allowed the tip to be opened and closed down at will. Beautiful work, but too labor intensive to produce in quantity.
Material: Titanium
Slot Cut: 0.008" EDM wire
Price: Unknown, provided by N.Mace.
Spot size: big

When working with this sort of metal, it is difficult to obtain the correct slot geometry. (Narrow at the point)
Material: 308L stainless
Slot Cut: 0.010" by grinding wheel
Price: $50
Spot size: Unpredictable

The steep angle used in this tip made for a very delicate point, prone to damage. The slot size, being large, yielded variable results.
Material: 308L stainless
Slot Cut: EDM wire
Price: unknown
Spot size: Unpredictable

The large cut out of this tip results in totally unpredictable spotting behavior. This tip had no chance of working.
Material: 308L stainless
Slot Cut: 0.008" by laser
Price: unknown
Spot size: Unpredictable

The slot size, being large, yielded variable results.
Material: 308L stainless
Slot Cut: 0.0015" by EDM wire
Price: $80
Spot size: 50um - 120um

Extremely small, consistent spots. Somewhat prone to clogging. This tip was Revision A, made by Majer Precision. Slight overburn near the point.
Material: 308L stainless
Slot Cut: 0.0015" by EDM wire
Price: $80
Spot size: 50um - 120um

Extremely small, consistent spots. This tip was Revision C, made by Majer Precision, and features a no-spin design. (requires a special holder)
Material: Tungsten Carbide
Slot Cut: 0.001" by EDM wire
Price: $100
Spot size: really small

Extremely small spots, but the tungsten carbide is suseptible to shattering, especially at the tip. In addition, the overburn near the tip causes most of the liquid to stay at the top of the slot, instead of near the point.
Material: 420 Stainless Steel
Slot Cut: 0.006" by EDM wire
Price: $30
Spot size: 150um - 200um

A nice tip, but very suseptible to rust. Not a good thing for printing DNA resuspended in high salt solution.

Material: 308 Stainless Steel
Slot Cut: 0.015" grinding wheel
Price: $30
Spot size: 150um - 200um

Difficult to reproduce copies with perfectly centered slots. The tip ends are bent together after cutting. This process is prone to variablity.
Material: 308 Stainless Steel
Slot Cut: 0.010" grinding wheel
Price: $30
Spot size: 150um - 200um

Shallow angle of this tip resulted in messy spotting characteristics.
Material: 308 Stainless Steel
Slot Cut: 0.015" grinding wheel
Price: $30
Spot size: 200um - 250um

Difficult to make centered slots. Steep angle, and variable bending cause unpredictable behavior.
Material: 308 Stainless Steel
Slot Cut: 0.001" EDM wire
Price: $90
Spot size: 75um - 150um

Beautiful tip. Made by Die-Tech semiconductor tooling. Excellent spot size and consistency. Difficult to clean, but worth the effort.