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Reply To: | TechNet E-Mail Forum. |
Date: | Thu, 10 Aug 2000 20:13:33 EDT |
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In a message dated 8/10/00 6:05:01 PM EST, [log in to unmask] writes:
<< the second puzzle of physics of heating interrupted HIGH = LONG barrels is
simple .
Almost regardless how slow you drive it (agree with Phil),
the designer actually f...ed up :
You DO need full contact (not a relief) to heat the >long< barrel and keep
it hot with significant inside dissipations, learned that one on PS's.
The high speed standard assembly and thick specials have non transferable
sets of physics, ie horses for courses, = tractor is faster than ferrari in
places.
One of the reasons why i hate standards = makes folks to asses with carrots
to follow
Enjoy yourself mate, no way out
paul >>
Hey Mate!!
So you're saying that on thick boards, one should not themally relieve plane
connections? Interesting...kinda' makes sense now that I think about it, you
need a lot of preheat for sure on thick boards, but having thermals in large
planes will not allow the heat to not be retained in a long barrel unless
it's connected to the heat...hmmmm...
Phil brought up a facet about increasing solder temperature...I've done
everything else (slowing belt speed, increasing pre-heat temps) but that,
only resulting in exhausting the flux before hitting the wave..which is not a
good thing...spikes, bridges, etc....so how much higher than 500-F should I
go? I'm also setting the wave depth that the board experiences when entering
the wave at the level where you could crack a walnut in between my
butt-cheeks when I'm watching a board go into the wave...in other words, it's
d-e-e-e-p bro'!
I get the feeling that I'm grasping at straws...as you said; "No way out..."
-Steve Gregory-
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