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Old 30th June 2015, 04:23 AM
hmangphilly hmangphilly is offline
Senior Member
Join Date: Nov 2013
Location: wimborne
Posts: 569

Originally Posted by Nick G View Post
I have been trying to improve on my o ring design, and along the way have noticed that if I use a very minimal crush on the o ring, ie, the piston falls under its own weight, I can use less spring for the same power, but the bounce increases by a considerable amount, so the friction must be controlling the bounce, the power starts to fluctuate also, so it must be bouncing by varying amounts shot to shot. so it seems a bit of friction may be a good thing.

I wonder if this could be the reason some are experiencing poi shift and others not, ie tight or loose seals. Just a thought
Hello NIck
sucking eggs tutorial coming up

that controlled friction idea crossed my mind briefly too with regard to pcp hammer bounce, where i think it's generally accepted now to keep friction and drag to a minimum, in order to achieve the widest spread of consistency

, the trouble with friction is that it's going to vary with temp.

so a "controlled " and consistent amount of friction to manage bounce etc is going to be difficult to achieve throughout the temp range and or a differing rate of shooting .

perhaps in a springer, it would be beneficial to use a low friction seal setup , which will give a wide range for heat expansion of the component parts, and try to control the bounce / slam /shot feel by another method......piston weight ( which will always stay the same )or perhaps the inertia weight principle that bigtoe was trialing.

i would suggest that for ft /hft ,consistency from shot to shot is the first thing to achieve and then try to adjust the shot feel afterwards

......completely ,and totally not intended to be condescending or patronising in any way .......

and failing probably
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