ramé-hart fabricates a variety of custom coaxial and triaxial needles for a wide spectrum of special applications. Some customers use ramé-hart coaxial needles for specialized surface science measurements (such as measuring surface dilatational elasticity and viscosity, surface tension on drops and bubbles, and mixing liquids at the point of measurement). Coaxial and triaxial needles are also used in the production of nanofibers made by electrospinning and electrospraying applications. The needles have excellent electrical conductivity. Note that the coaxial needle is often referred to as a coaxial cone when used in electrospinning and electrospraying applications due to the cone observed at the tip where fiber is drawn out from what is referred to as the "Taylor cone".
Shafting is precision Type 304 Stainless Steel while the Luer connector is nickel and chrome-plated brass. These needles are autoclavable; they can be cleaned, washed, boiled, sterilized, and reused many times. Many options and tubing sizes are available to fit any application.
Most of the coaxial and triaxial needles that we fabricate are custom made. However, we also carry (4) different prebuilt coaxial needles (see http://www.ramehart.us/prebuilt-coaxial-needle/) and one prebult triaxial needle (see http://www.ramehart.us/prebuilt-triaxial-needle/)
Each custom needle is made to your specifications. To design and order your own coaxial/triaxial needle design follow these three simple steps:
1. Download the needle chart here: http://www.ramehart.com/pdf/needles.pdf to help you determine which gauge needles you require. This chart shows the ID (inside) and OD (outside diameters) for all standard needle gauges. Be sure that the OD of the inside needle you choose is smaller than the ID of the outside needle. Note that currently we are not fabricating any coaxial or triaxial needles with an inside needle greater that 28 gauge.
2. Download our coaxial needle design worksheet here:http://www.ramehart.com/pdf/coaxial_worksheet.pdf Figure out your inside and outside gauges along with connector type for the side fitting (Style A or B or C). Figure out the other dimensions and options per your requirements as detailed on the worksheet. Please note that innermost needle must be 28g or lower.
To see more examples of custom made coaxial needles, please visit our flickr page.
Note that standard delivery time for this item, since it is custom made, is one week.