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After coiling the microbore tubing tightly around its spool, the puller can be used to grip the microbore tubing and stretch it, as shown below.
Stretching can also be accomplished by wrapping the tubing around the handle of a screwdriver, for example, in the absence of the puller.
Once the tubing is sufficiently stretched, locate the section of tubing where the cross section is narrowest. It is here that the tubing should be cut so that it can be pulled through the narrow opening. When cutting, try to make the cut at an acute angle, as shown below, so that the tubing will fit even more easily into narrow the opening of the barbed fitting.
If the tube has been stretched enough and the cut has been made neatly, it should be fairly easy to pull the tubing through the narrow opening of the barbed fitting. Once the tubing comes out the other side of the fitting, pull it through until it fits snugly in the opening of the fitting, as shown below.
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The same process of stretching the microbore tubing to fit it snugly in smaller openings into the barbed fitting can be applied in used for other placesapplications. One common application is to bore a 1/16" hole in a 1/4" push-to-connect plug so that the plug can then be inserted into a push-to-connect through-wall or tee fitting. This is the most common way to make the connection between microbore tubing and an experimental apparatus.
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