"ignator" wrote in message
...
On Mar 21, 5:54 pm, Dan@ (Pirateer guy) wrote:
I need to make a part out of rubber. The part is obsolete and cannot
be purchased. I have one, but it has shrunk over the years and is now
loose and it leaks water.
The part is an isolation ring for a boat engine mount. It sits between
two pieces of aluminum and is compressed by the two pieces.
This allows some movement between the engine and the engine mount and
it also seals out the water.

I am thinking that I can use the existing part to make a mold to build
a new part out of urethane. I can add bulk to the existing part to
make up for the shrinkage.
Problem is, all I can find on the web is urethane for making the mold
not the part. Does anyone have any insight into how I can do this?
Fairly complex part, but I have one to make the mold from.
The link is to a parts manual that shows this part. It is on page 14,
of 20 and it is Item Number 8. It is OMC part number 322214or OMC
393162. same part.
Thanks everyone
Dan

This is not a replay to the OP, but a request for WHAT IS THE
DUROMETER for rubber grommets. I need to make one for a antique
Lauson engine. So it needs to be flexible enough to push into a .25
hole, .1 thick groove, and .5 od. All square edges. I tried off the
shelf, but nothing I found fit this. I would not suspect anyone would
figure out a radius-ed version, but if I have to make one, I'll try
exact replacement copy. This is for a ignition wire feed through from
the magneto coil.
And next would this be a castable material (flexible enough to insert
into hole) that is procurable.

ignator

Take a look at How to Cast Small Metal and Rubber Parts on Amazon. The book
lists the durometers of various car parts, so you may be able to figure out
what's equivalent.

--
Ed Huntress