"Kendall, Thomas" wrote:

Paul,

I'm at work and don't have the list e-mail address.  But here's some photos of the intake manifold pattern I just took.  Hope the are helpful in getting an estimate from a western foundry.

The first one is an overall view of the whole she-bang, complete with 4 plaster casts of the cores from the core boxes (I've since reworked the core boxes slightly to adjust the fit to the prints on the pattern).  The top is the main pattern, together with a loose piece that is used when ramming up the cope.  This mold is made "upside down":

1)  The pattern and loose piece are placed on a board along with the sprue pin and any risers.  Then the *cope* is rammed up.

2)  The cope is rolled over (now upside down) and the loose piece removed.  The 4 conical loose prints inserted on the bottom of the pattern.

3)  The (upside down) drag is placed on the upside down cope, and the drag rammed up.

4)  The drag is removed and rolled, the loose prints drawn from it, and the cores set in the drag.

5)  The pattern & sprue pin, risers, etc. are drawn from the cope, and the cope then placed on the drag ready for pouring.

The second photo shows the pattern rolled over with the loose prints installed and the loose piece removed (end of step 2).  The ruler is provided for scale.

The third photo is another view of the rolled pattern with loose prints installed and the loose piece still in place.  Sort of in the middle of step 2.

Fourth photo is a top view of pattern with loose piece in place.  Provides scale and overall plan view.

Fifth photo is an oblique view of the backside.  More for perspective than anything else.

I checked the finished pattern against the stock manifold and if compares very favorably (Surprise!).  The finished part will be slightly shorter than the pattern appears because, besides shrinkage allowance, the pattern has a 1/8" machining allowance built into the pattern mounting base.

Tom

Fifth photo

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