Discussion and questions related to the course Practical Harness Construction - Club Level
Does the length of a piece of DR-25 change by heating? Or does the shrinkage affect its diameter only?
It can change length, yes. Depends on duration and how evenly you apply heat.
Is there a rule of thumb for how much a given length will shrink assuming it's recovered with appropriate temperature and time? Does the expected percent of length shrinkage vary with the off-the-shelf tube diameter? Thank you.
Length shrinkage is very low, hard to say in % really. I feel it changes with diameter as well. On 1000 mm it should maybe be not more than 10 mm, so less than 1%. At least this would somewhat be my hands-on observation.
I have had batches that seemed to length shrink more than others. Hard to say for sure, though. Check the data sheet and see if it specifies this somehow.
I only use the nice white print DR25, not the yellow print one.
Thanks very much. Worst case, I can always do some simple experiments by measuring the length of a sample before and after heating for the diameters I'm interested in.