My colleagues have written plenty of articles over the years with how to cut columns and get the perfect press-tight connection:
Jaap – How to make a good fused silica seal using a Press Tight type connections
Jaap – Column cutting, for making the optimal coupling
Chas – How (not) to cut your capillary column
But we haven’t really focused on what are the consequences of poor cuts and poor installation.
As Chas pointed out in his article you can make a bad cut. This can be achieved by doing things like pressing too hard on the column on the column with the wafer when scoring or using the serrated edge of the wafer. The consequences are a jagged edge that would be hard to seal or even creating fissures in the column that compromise the strength of the column. These in turn can lead to poor connections or a crushed column.
Poor cut and uneven seal
We have seen poor seals like this disconnect during the heating cycle of the GC program, and thus lead to a leak, and probably a damaged analytical column.
Fractures in column because of a poor cut leading to a poor seal
Another problem we have seen is people using too much force to insert the column into the press-tight to get a seal. This has consequences too. In the following examples we that it can lead to both column and press-tight damage
Crushed end with poor seal after column strength compromised
Press-tights shattered and cracked after columns that were inserted to firmly expanded during the GC program and fractured the glass.
Shattered
Cracked
Tags: Column cutting, press tight, presstight
