METHOD FOR SECURING CORE TO TOOL DURING MACHINING
A method for preparing a part using a rigid tool surface having a shape. The method includes applying a breather sheet comprising gas-permeable material over the rigid tool surface. A vacuum bag is applied over the breather sheet, and a vacuum pressure is applied underneath the vacuum bag to conform the breather sheet and the vacuum bag to the shape of the rigid tool surface. A resin pre-impregnated ply is applied over the vacuum bag, and the part is positioned over the ply.
1 . A system for preparing a part using a rigid tool surface having a shape, the system comprising:
a vacuum bag positioned over the rigid tool surface and being under vacuum pressure conforming the vacuum bag to the shape of the rigid tool surface; and
a resin pre-impregnated ply positioned adjacent the vacuum bag opposite the rigid tool surface,
wherein the part is positioned adjacent the ply opposite the vacuum bag.
2 . The system of claim 1 , further comprising -
a second vacuum bag positioned adjacent the part opposite the ply and being under a second vacuum pressure pressing the part against the ply.
3 . The system of claim 1 , wherein the part comprises a honeycomb core.
4 . The system of claim 3 , wherein the honeycomb core comprises at least one of fiberglass and aluminum.
5 . The system of claim 1 , further comprising -
a breather sheet applied between the rigid tool surface and the first vacuum bag.
6 . The system of claim 1 , wherein the rigid tool comprises one or more of aluminum, steel and fiberglass.
7 . The system of claim 1 , wherein the part comprises two pieces each having an interface surface.
8 . The system of claim 7 , further comprising adhesive adhering the interface surfaces of the two pieces to one another.
9 . The system of claim 1 , wherein the part has at least two (2) thicknesses including a reduced thickness.
10 . The system of claim 1 , wherein the pre-impregnated ply comprises a sheet of polyester peel ply support carrier pre-impregnated with resin.
11 . The system of claim 1 , wherein -
the vacuum bag comprises a first perimeter portion and a substantially opposite second perimeter portion,
the rigid tool comprises a first perimeter portion and a substantially opposite second perimeter portion,
the first perimeter portion of the vacuum bag is sealed against the first perimeter portion of the rigid tool and the second perimeter portion of the vacuum bag is sealed against the second perimeter portion of the rigid tool.
12 . The system of claim 11 , wherein the respective perimeter portions of the vacuum bag are releasably sealed to the corresponding perimeter portions of the rigid tool.
13 . The system of claim 1 , further comprising -
a second vacuum bag positioned over the part and being under vacuum pressure from a second vacuum source conforming the second vacuum bag to the shape of the part.
14 . The system of claim 13 , further comprising -
a breather sheet placed between the part and the second vacuum bag, the breather sheet comprising gas-permeable material.
15 . The system of claim 13 , wherein the first and second vacuum sources are configured for independent application of pressure and corresponding independent release respectively of the first and second vacuum bags.
16 . The system of claim 13 , wherein -
each of the first and second vacuum bags comprises a perimeter portion,
the rigid tool comprises a perimeter portion,
the perimeter portions of the first and second vacuum bags are sealed against the perimeter portion of the rigid tool.
17 . The system of claim 16 , wherein -
the perimeter portion of the rigid tool comprises an edge flange having an inner portion nearer the part and an outer portion further from the part,
the perimeter portion of the vacuum bag is sealed against the inner portion of the edge flange,
the perimeter portion of the second vacuum bag is sealed against the outer portion of the edge flange,
the vacuum pressure supplied by the first vacuum source is along the inner portion of the edge flange,
the vacuum pressure supplied by the second vacuum source is along the outer portion of the edge flange.
18 . The system of claim 13 , wherein each of the first and second vacuum sources comprises a vacuum port configured to deliver vacuum pressure across a substantially rigid and gas-permeable mesh screen.
19 . The system of claim 1 , wherein the resin pre-impregnated ply is cured and is attached to the vacuum bag, the attached ply and vacuum bag being configured to be peeled away from the part.
20 . The system of claim 19 , wherein the resin pre-impregnated ply comprises a wet peel ply.