I have traditionally used hook spring compressors (two hooks on a spiked threaded rod) - they work well but not very close - I have used them to install luggage racks on my Subaru - worked great! I followed the advice here and gave the internal threaded rod a good lube, put it back together and raced. I suspect people who have had trouble with this either use percussion tools (no-no for spring compressors) or have them at a high angle to the coils so they stick or something. I had absolutely no problems and this was the easiest set I have ever used. The design also gives you something to hold on to while you tighten them, which is nice. The only thing that I think will help people is the instruction manual or manual - nothing is really included. So if this is your first time installing racks I would watch some videos or ask someone to help you (there is a lot of energy stored in a compressed spring so you have to be careful)