[NSRCA-discussion] Soft Mounts (Beam)

[JShulman]

Just throwing this out there, but at one time I was told that if you freeze
DB wheels, you could reshape them. What would happen if you froze the pieces
of rubber before cutting and drilling them?

Regards,
Jason
www.jasonshulman.com
www.shulmanaviation.com
www.composite-arf.com

  -----Original Message-----
  From: nsrca-discussion-bounces at lists.nsrca.org
[mailto:nsrca-discussion-bounces at lists.nsrca.org]On Behalf Of Paul LaChance
  Sent: Friday, December 14, 2007 7:38 PM
  To: NSRCA Mailing List
  Subject: Re: [NSRCA-discussion] Soft Mounts (Beam)


  Lance and others interested,

  Find a bet that is bigger than the isolator in all direction.  Mine was
for the blade drive on a riding mower.  I cut the pieces to the original
dimentions using a scroll saw.  The I drilled the holes in the rubber with a
small drill bit and worked my way up to the right size.  It takes SEVERAL
times drilling with the correct size drill bit to actually open the hole
properly.  The rubber will keep trying to strech instead of letting the bit
drill cleanly.  Then, mount as usual.  I have used these home made isolator
for about 20 flights with no sign of wear.  Until that time they were
cracking or turning into gummy bears about 1 a day, so every 4 days of
flying required all 4 isolators to be replaced.

  Strangly I never had this problem about 10 years ago.  I do not know if
they changed the rubber they were made from, but the new rubber does not
last like the old rubber did.  Also the ones for World Engines brand mounts
work but are VERY hard and stiff.  They shook the plane terribly and had to
be removed after 2 flights.

  Paul
    ----- Original Message -----
    From: Lance Van Nostrand
    To: NSRCA Mailing List
    Sent: Friday, December 14, 2007 7:28 PM
    Subject: Re: [NSRCA-discussion] Soft Mounts (Beam)


    Paul, intersted in more details of how you fabricated an isolator from a
belt.

    Still, anyone melting vulcanized rubber has some serious cooling
problems.

    --Lance

      ----- Original Message -----
      From: Paul LaChance
      To: NSRCA Mailing List
      Sent: Friday, December 14, 2007 6:10 PM
      Subject: Re: [NSRCA-discussion] Soft Mounts (Beam)


      I had the same thing happen.  Even a new set just purchased did the
same thing.  I ended up making my own out of a belt for a riding mower.  The
belt was $10 and you could probably make about 100 isolators out of it.  The
good thing is it is designed to take the heat and be break resistant.  The
cloth molded into it makes it almost impossible to tear.  Just make sure you
cut the piece to shape and drill the holes accurately.  I used the home made
isolators at the Triple Tree contest this year.  Give it a try.  It seemed
to have the damping as the priginal isolators.

      Paul
        ----- Original Message -----
        From: Bill Thompson
        To: nsrca-discussion at lists.nsrca.org
        Sent: Friday, December 14, 2007 6:47 PM
        Subject: [NSRCA-discussion] Soft Mounts (Beam)


        Has anyone had the rubber for these mounts soften and melt. This is
the second time in the last year it happened.The mounts are MK using Dave
Brown VibaDamp 4/C Isolators.
        BillT


------------------------------------------------------------------------


        _______________________________________________
        NSRCA-discussion mailing list
        NSRCA-discussion at lists.nsrca.org
        http://lists.nsrca.org/mailman/listinfo/nsrca-discussion


--------------------------------------------------------------------------


      _______________________________________________
      NSRCA-discussion mailing list
      NSRCA-discussion at lists.nsrca.org
      http://lists.nsrca.org/mailman/listinfo/nsrca-discussion


----------------------------------------------------------------------------


    _______________________________________________
    NSRCA-discussion mailing list
    NSRCA-discussion at lists.nsrca.org
    http://lists.nsrca.org/mailman/listinfo/nsrca-discussion
No virus found in this outgoing message.
Checked by AVG Free Edition.
Version: 7.5.503 / Virus Database: 269.17.2/1184 - Release Date: 12/14/2007
11:29 AM
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.nsrca.org/pipermail/nsrca-discussion/attachments/20071215/aeb2cf85/attachment.html