Here is a reference for pulling quartz glass pipettes using a custom oxy hydrogen burner. Here is a video of a commercial burner based pipette puller. Not sure what the specs are. I guess if you can melt your glass using a filament it could be easier than using a torch (a lightbulb circuit is easier to control than flame). People move to flame when dealing with high melting point quartz.
You can get a micropipette puller from Sutter for $1500 off of Ebay. I'm not completely sure how they work mechanically, but I have used many models. Someday I'd like to look inside them (the true mechanism is underneath, inside the box). They use a metal "boxcar shaped" filament that fits around the cappilary, and this heats up when a current is passed through. Two pulleys pull at the pipette, attached to something below doing the actual pulling.
I think there might be a spring-loaded mechanism for achieving the pull, rather than a motorized linear stage moving so fast. Maybe a stage or other actuator below pre-stretches a spring so that it is pulled to different degrees during melt cycle?
No comments:
Post a Comment