Claims
- 1. A method of forming a nail slot in a molded hardboard building panel having an outer face and a back face, comprising the steps of:
- molding a depression in said outer face during the initial consolidation of a relatively thick mat of wood fibres into a relatively thin sheet of molded hardboard material forming said panel and resulting in a mold-formed projection opposite said depression protruding outwardly on said back face;
- curing said molded hardboard material into relatively rigid form after said initial formation; and
- removing said projection from said back face to form an opening between said faces comprising said nail slot.
- 2. The method of claim 1 wherein a plurality of said nail slots are provided, aligned in a row, comprising the steps of:
- forming a plurality of said depressions and opposite projections along a row during the molding of said panel; and
- removing said projections to provide a plurality of open nail slots along said row by relative movement between said panel and a cutting means in a direction along said row.
- 3. The method of claim 2 wherein said back face of said panel is surfaced by said cutting means to form a planar strip while said projections are being removed.
- 4. The method of claim 2 wherein said panel comprises one of several panels in a common molded blank, including the steps of:
- separating said one panel from said blank while said projections are being removed.
- 5. The method of claim 4 wherein upper and lower edges of said one panel are trimmed while said one panel is being separated from said blank.
- 6. A method of making an opening extending between opposite faces of thin sheet material, comprising the steps of:
- initially mold-forming a relatively thick mat of wood fibrous material into a relatively thin, hardboard panel providing at least one depression in one of said faces having a depth greater than the nominal thickness of said sheet material between said opposite faces, said molded depression resulting in a projection being formed on said other face opposite said depression and protruding outwardly from said other face;
- solidifying said molded hardboard panel and said projection into a rigid form; and
- mechanically removing said rigid form projection from said other face to form said opening extending completely through said sheet material between said opposite faces thereof.
- 7. The method of claim 6 wherein said sheet material comprises a substantial proportion of composite wood fibrous material consolidated under heat and pressure.
- 8. The method of claim 6 wherein said projection is removed by a machining operation.
- 9. The method of claim 8 wherein said machining operation is effective to provide a planar surface on said other face around the perimeter of said opening.
- 10. The method of claim 6 wherein said depression includes opposite wall surfaces sloping toward one another and toward said other face.
- 11. The method of claim 6 wherein a plurality of said depressions are formed a spaced apart locations on said one face, and
- wherein said projections are subsequently removed by machining in single pass running between adjacent ones of said projections.
- 12. A method of making a wood fibre object having one or more slots therein comprising the steps of:
- initially mold forming by heat and pressure a first surface of said object from a mat of unconsolidated wood fibres to provide one or more depressions therein extending toward a second opposite surface being simultaneously mold formed on said object resulting in a projection on said second surface opposite each depression and extending outwardly of a surrounding portion of said second surface;
- solidifying said wood fibres into a consolidated sheet whereby said projection(s) becomes rigid in shape; and
- mechanically removing said rigid projection(s) so formed resulting in the formation of one or more slots extending completely through said object between said first and second surfaces.
- 13. The method of claim 12 wherein:
- a plurality of said depressions are formed at spaced locations in a row on said first surface; and
- said projections opposite said depressions are removed by machining in a single pass along said row on said second surface.
- 14. The method of claim 12, wherein:
- said depressions have opposite facing wall portions sloping inwardly toward one another between said first and second surfaces.
Parent Case Info
This application is a division of application Ser. No. 629,625, filed July 11, 1984, now U.S. Pat. No. 4,617,774.
US Referenced Citations (26)
Foreign Referenced Citations (2)
Number |
Date |
Country |
2016045 |
Oct 1971 |
DEX |
0000016 |
Jan 1874 |
GBX |
Divisions (1)
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Number |
Date |
Country |
Parent |
629625 |
Jul 1984 |
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