Carbon Dioxide Snow Cleaning
by Applied Surface Technologies
Telescope Cleaning
Introduction
Carbon Dioxide Snow Cleaning offers a quick, effective, and inexpensive way to clean large telescope mirrors. Astronomers have cleaned mirrors ranging in size from several inches up to 25 feet (8 meters). This application is based upon the low velocity CO2 snow cleaning mode. Here, we use a larger expansion zone that changes the initial CO2 snow exiting the orifice from a high velocity, small dry ice, to a large snowflake with a low velocity. This mode is aimed at removing particles from microns on up and is quite effective. Organic removal is not likely in this mode. Furthermore, the working distance is much greater than with the high velocity mode. Users can operate several feet (meter) from the mirror making sure there is no risk of contacting the mirror.
The equipment is similar to the high velocity mode but with a different orifices and nozzle assembly. We use the same hose and on/off gun as shown on the equipment page but the orifice has a larger internal diameter. Upon exiting the orifice, the stream enters a polymer expansion tube, usually an inch (25 mm) in diameter and 18 or 30 inches long (460 or 760 mm). This low velcoity stream strikes the mirror with diameters larger than 1 inch (25 mm. Note, for large mirrors, we suggest a two inch nozzle below.
Below, we show the equipment, provide two videos, and a price list. Observatories can qualify for discounts.
Equipment and Prices
The basic low velocity CO2 snow cleaning system is based upon the equipment for the standard K1-10 shown on the equipment page. We remove the asymmetric Venturi nozzle and add a simpler nozzle and expansion zone tube. Overall, the image below, shows the various items for the low velocity and high velocity CO2 snow cleaning modes. Demonstration videos are below
Large Area Snow Unit Model K1-10LASU-C
Slot Nozzle
Large Area Snow Unit Model K1-10LASU-A
CO2 Telescope Units
1 – K1-10LASU-A - Basic model with CO2 cylinder fitting, hose (10 feet), on/off gun, and one nozzle and tube for telescope cleaning -- $1095.00 Add $75.00 if a DIN, JIS, or BS CO2 fitting is ordered. Select expansion zone length
2 – K1-10LASU-C – Basic Telescope and Precision cleaning unit – This unit is a K1-10 for precision cleaning, with the telescope cleaning parts and extra nozzles. Price- $2,395.00. Includes the Venturi, high and low flow nozzles for the precision cleaning mode. Expansion tube lengths 18” or 30”. No charge for extra tube nozzles. Particle, hydrocarbon, and organic removal. Select expansion zone length. Add $75.00 if a DIN, JIS, or BS CO2 fitting is ordered.
3 - K1-05-LV – Basic model with CO2 cylinder fitting, hose (5 feet), on/off gun, and one low velocity nozzle. This unit is good for smaller telescope mirrors and optics. $975.00 Particle removal only. Add $75.00 if a DIN, JIS, or BS CO2 fitting is ordered.
Options
Pressure gauge (PG) – 0 – 2000 psi (0- 75 bars) on a TEE by the CO2 cylinder fitting -- $200.00
Filter F1 - Stainless Steel filter rated at 0.5 placed before the handgun -- $125.00
Solenoids, pneumatics, and actuators are available. Please email for information.
SLT-2 --Slot Telescope Nozzle – 5 cm (2”) CO2 snow stream - Add on to any of the above units -- $1350.00. The stream expands to about 6 – 7 cm (3 - 4 inches) at normal working distance.
SLT-4 --Slot Telescope Nozzle – 10 cm (4”) CO2 snow stream - Add on to any of the above units -- $1850.00. The stream expands to about 15 – 17 cm (about 6-7 inches) at normal working distance.
Videos
One Inch Expansion Tube
Two Inch Slot Nozzle
Cleaning a mirror with
K1-10-LASU-A
