Forwarded from bounce bin. Message is from
"Peter M. Davis" <pdavis10@compuserve.com>
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I have the black suspension block, so things may be a bit different to the
red block but...........and IMVHO.....and I'm sure everyone will put me
straight where I've got it wrong, but.................
I don't know about any 'squashy memory' that the blocks may have - I'll be
looking at this when operational again - but I too noticed that when the
plane is on the ground the bolts connecting the upper and lower plates are
slack. I asked Andy about this and he said that this was normal, so I was
happy :-).
However, on thinking about the landing gear geometry I concluded that with
the wheel unloaded, the distance between the reaction plates affects the
amount of 'overcentre' experienced by the LG08 forks against the landing
frame stops. Don't quote me, but I seem to remember that the more the bolts
are tightened, the more overcentre is applied. Conversly, less tightening
gives less overcentre, which could be embarrassing when landing as there
could be more likelyhood of the whole caboodle jumping out at the wrong
time.
At the time of building I was quite keen not to overtighten the bolts as I
thought it would increase the load on the stops - and thereby the frame -
as the u/c geometry angle would allow more load to be transmitted to the
stops rather than straight down the LG08s.
Since realising that at rest on the ground the bolts are slack, and will be
more so under landing load, slightly tighter bolts would not make any
difference to the load imposed on the landing frame and only affect the
amount of overcentre (and hence the position of the retracting lever LG12)
when lowered in the air. Do correct me, Andy.
At this point I put my brain back on the shelf and applied myself to the
manual in the knowledge that there are much better people out there
thinking very hard about all these difficult things.
Happy New Year to one and all!
Peter Davis (#154) - struggling with mod 58 :-(
PS - Whilst on the matter of suspension, I too have just replaced all the
bushes in all the links as they were allowing a lot of play in the system.
Maybe the factory could comment on Graham's suggestion of using harder
metal.
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