[DeTomaso] A-arm bushings...should they require machining?

[Julian Kift]

Chuck,


I think the difference here is oem rubber style bushings designed to be a press fit vs. aftermarket poly bushings. We recently had a long discussion on the merits of each, so won't rehash that, but I'm aligned with Joseph's thinking that 0.003" would be the expected interference fit for a bushing of this size. At 0.008" over, I'd probably turn them down or failing access to a lathe at least spin them up on a sander to lose some of that oversize.


If I recall correctly there is a very slight splay on the A-arms to effect starting the press fit.


Julian

________________________________
From: DeTomaso <detomaso-bounces at server.detomasolist.com> on behalf of Charles Engles <cengles at cox.net>
Sent: Thursday, September 21, 2017 6:11 PM
To: 'Joseph F. Byrd, Jr.'; detomaso at server.detomasolist.com
Subject: Re: [DeTomaso] A-arm bushings...should they require machining?

Dear Joe,


                    I  don't know.

                    I do know that twenty odd years ago when I converted
both Panteras to polyurethane bushings from Pantera Performance Center, they
went in with just finger/hand pressure.  No press needed.   Obviously, they
must have been smaller than yours and I don't understand why there is such a
great difference.

                                      Puzzled,  Chuck Engles



-----Original Message-----
From: DeTomaso [mailto:detomaso-bounces at server.detomasolist.com] On Behalf
Of Joseph F. Byrd, Jr.
Sent: Thursday, September 21, 2017 5:32 PM
To: detomaso at server.detomasolist.com
Subject: [DeTomaso] A-arm bushings...should they require machining?

I have removed the bushings from the front A-Arms and have found their ODs
to be a consistent 1.184".   the A-arm bore IDs varied slightly around
1.181".   this makes sense as the IDs would be 30mm with the bushings
oversized for MY expected press fit of ~ 0.003".



NOW, the new bushing ODs vary around 1.189".   to ME, that is way too much
press and could plastic yield the A-arm bores.



Is it expected to machine the new bushing ODs?  (Pretty common practice for
new parts to be oversized for field fitting  in the machines I use to work
to allow for possible damage/wear.)

OR

Throw away the micrometers and get a bigger press?





Joe/5177


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-------------- next part --------------
   Chuck,

   I think the difference here is oem rubber style bushings designed to be
   a press fit vs. aftermarket poly bushings. We recently had a long
   discussion on the merits of each, so won't rehash that, but I'm aligned
   with Joseph's thinking that 0.003" would be the expected interference
   fit for a bushing of this size. At 0.008" over, I'd probably turn them
   down or failing access to a lathe at least spin them up on a sander to
   lose some of that oversize.

   If I recall correctly there is a very slight splay on the A-arms to
   effect starting the press fit.

   Julian
     __________________________________________________________________

   From: DeTomaso <detomaso-bounces at server.detomasolist.com> on behalf of
   Charles Engles <cengles at cox.net>
   Sent: Thursday, September 21, 2017 6:11 PM
   To: 'Joseph F. Byrd, Jr.'; detomaso at server.detomasolist.com
   Subject: Re: [DeTomaso] A-arm bushings...should they require machining?

   Dear Joe,
                       I  don't know.
                       I do know that twenty odd years ago when I
   converted
   both Panteras to polyurethane bushings from Pantera Performance Center,
   they
   went in with just finger/hand pressure.  No press needed.   Obviously,
   they
   must have been smaller than yours and I don't understand why there is
   such a
   great difference.
                                         Puzzled,  Chuck Engles
   -----Original Message-----
   From: DeTomaso [[1]mailto:detomaso-bounces at server.detomasolist.com] On
   Behalf
   Of Joseph F. Byrd, Jr.
   Sent: Thursday, September 21, 2017 5:32 PM
   To: detomaso at server.detomasolist.com
   Subject: [DeTomaso] A-arm bushings...should they require machining?
   I have removed the bushings from the front A-Arms and have found their
   ODs
   to be a consistent 1.184".   the A-arm bore IDs varied slightly around
   1.181".   this makes sense as the IDs would be 30mm with the bushings
   oversized for MY expected press fit of ~ 0.003".

   NOW, the new bushing ODs vary around 1.189".   to ME, that is way too
   much
   press and could plastic yield the A-arm bores.

   Is it expected to machine the new bushing ODs?  (Pretty common practice
   for
   new parts to be oversized for field fitting  in the machines I use to
   work
   to allow for possible damage/wear.)
   OR
   Throw away the micrometers and get a bigger press?


   Joe/5177
   _______________________________________________
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   list. They also grant the list owner permission to maintain an archive
   or approve the archiving of list messages.

References

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