#1
I bought a scale to measure how strong the hydraulic springs
need to be.
(8/23/03)
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#2
Here's an early spring configuration. The two springs wouldnt hold
the door open all the way, even with 240 lbs of force. Moving mounting
points just a few inches in the right direction makes a big difference.
(8/23/03)
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#3
The Fiero door is so heavy that big springs are needed to keep it open,
then it's hard to close the door. Cutting off "unneeded" crash protection
weight helps solve the problem. The main beam across the middle weighs
10 lbs! (I hope to be able to put some crash protection back when i have the springs
configured correctly.)
(8/23/03)
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#4
I even tried an Autoloc Linear
Actuator. It's first problem was the 8" stroke takes 15 seconds to open
or close. Mounting near the hinge (with a spring helping) cut that in half,
but the door bounced around a lot on the way down when the weight shifted from
the spring to the actuator. It looked very bad, and took too long.
(12/30/03)
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#5
I tried all mounting positions suggested by street dreams, but always found that
if the spring was strong enough to hold the door open, it was too hard
to close the door. The reason for this is that the springs, according
to
Suspa, gain up to 80% more force when
compressed.
(12/30/03)
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#6
Finally, the
Evoluzione II revealed the secret on how to use these springs
to balance the door. The spring must loose it's leverage as it gains
force. So, as you close the door and the spring is going up in
strength, it must also be pointing more at the hinge, and thus lifting
the door less. As you can see from the above drawings, that principle
is not being applied.
(12/26/03)
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#7
Kitty litter and assorted weights model the glass (10 lbs) and
fiberglass (15 lbs!) so that the scale can attach whereever it needs
to.
(12/31/03)
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#8
mounting points farther away from the hinge line (in red) will
give better leverage. when the door is closed, the spring should
have almost no push (it should be almost pointing at the hinge);
just enough to lift the door a few inches when
it's popped open.
(12/31/03)
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