Jerry Hey wrote:

Hi Paul,  I just got off the phone with the Barry Mount factory
rep.  in
Mass.   When I told him I wanted the 140lb isolator  he said there
was
no such thing.  According to a chart which I downloaded the 20002-11
mounts are rated at 130 lbs.  I told him that the engine weighed 300
lbs
and he recommended the 20002-12 isolators which are rated at 175 lbs.
He cautioned me against overloaded the isolators as they would break
down.  He said that two 175 lbs isolators would dampen the movement
of a
three hundred pound engine effectively.     That is what I ordered.

Another complication is that the mounting bracket needs to be .563
thickness so it will have to be machined out of heavier material.
---Jerry

 175 pounds sounds fine with me. The 140 number was from memory which
at my
age
 is getting unreliable. Just make a 2.5 inch dia. .065 thick aluminum

washer

 and bond it to the 1/2 inch plate. Unless of course you REALLY WANT
to
machine the
 rubber mount holder out of 5/8  or 3/4 aluminum plate on the NC
mill :-)>

 I don't think it is all that important and I will try the 1/2 inch
plate
first.
 It is something that can be easily changed later.

 I think the Barry rep is being overly conservative and covering his
ass.

 Paul Lamar

Paul,
the thick center mount 22002-12 has axial load bearing of  175# and
Radial of
65#, which with two mounts gives you 130# of thrust capability.

The thin center -13 (optional) uses 0.5 plate, and has an axial of
160# each,
and a radial of of 125# which allows for 250# thrust with two.

Wouldn't that be better?

Bill Schertz
KIS Cruiser #4045

Looks like it. Hard to believe the thinner plate has a higher radial.
Never noticed that. I really don't think any of it is critical.
It's rubber after all. These are so cheap I bought a bunch of different
dash numbers and it is hard to tell the difference.

Jerry, before you buy that 5/8 bar stock check with the Barry rep on
this.
Looks like Bill is on to something. Don't cut anything until you get
the bushings. Some of the dimensions might be different.

Paul Lamar

I was looking at the Barry site trying to find their phone number again
when I ran across a graph comparing the thick and thin center options.
It clearly shows that the thin center option is far less resistant to
radial load.  For 400 lbs load the thin center option will deflect
somewhat greater than 0.05" while the thick center option does not reach
0.05" until the load is more than 500 lbs.   The chart is wrong.   How
many times when we are searching for FACTS  are we fed error or
downright bullshit?    I just bought a new lathe and the engraved plate
showing spindle speed at different gear combinations  is wrong!!!
Hard to find a firm rock to stand on.   What I really appreciate about
this newsletter is the relentless attack on bad information.   Thanks
Paul,    Jerry

 
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