G'day mate,
Thanks for posting your build, my next builds are going to contain alot of hyd functions so im reading all these threads closely to see what I can learn(which thanks to kind people like yourself is quite abit).
As for your method of compressing the collar, could you make an attachment similar to these pliers (or modify them for this purpose )
http://www.banggood.com/Ball-Link-Pl...FY2CvQod0UAABg
That way your pressing from behind the fitting and thus not flaring the fitting.
Working in HCAV recently we had a suby do around 30 shody flare connections some were at 30degree some were correct at 45 but had the most tiny of scratches on the flare needless to say (and due to poor management) the system leaked, $15k + labour to fix, but honestly those scratches were so small it was unbelievable the connections failed, fyi those systems run around 300psi so its made me reevaluate our connections much more thoroughly - im still looking for an answer; and reinventing a square wheel im sure.
Also the kinked pipe you may want to swap out, while im unsure in hydraulics cavitation has caused huge issues for us in other systems and considering the pressures we're dealing with here i could envisage a frothy result.