Claims
- 1. A process for shaping a workpiece and for producing a workpiece surface contour complementary to the surface contour of a model desired to be reproduced, the process comprising the steps of:
- (a) providing a non-planar template which is a negative image of the workpiece surface contour to be reproduced;
- (b) applying a coating of an etchant resistant masking material to at least a portion of the surface of said workpiece, said masking material being adapted to protect said workpiece surface from the effects of etchant;
- (c) pressing said template against said workpiece surface;
- (d) withdrawing said template from said workpiece surface to selectively adhere the masking material to the template and correspondingly selectively remove masking material from those portions of said workpiece surface contacted by said non-planar template surface;
- (e) applying etchant to said workpiece surface to etch portions of said workpiece surface not covered by said masking material; and
- (f) repeating steps (b) through (e) until the surface contour of the workpiece conforms to the nonplanar surface contour of the model.
- 2. A process as set forth in claim 1 wherein following the step of withdrawing said template, the process further includes the steps of cleaning said template of said masking material, and repeating said steps of pressing said template against said workpiece surface, withdrawing said template and cleaning said template of masking material until said template ceases to remove appreciable quantities of said masking material from said workpiece surface.
- 3. A process as set forth in claim 2 wherein following said steps of applying etchant, said process further includes the steps of cleaning said workpiece surface to thereby remove said masking material and recoating said workpiece surface with said masking material.
- 4. A process as set forth in claim 1 wherein said template is comprised of cast room temperature curing uethane.
- 5. A process as set forth in claim 1 wherein said step of applying a masking material to said metal workpiece includes the application of a coating of re-etching ink to said workpiece surface.
- 6. A process as set forth in claim 1 wherein said step of applying a masking material to said workpiece surface includes the application of asphaltum varnish to said workpiece surface.
- 7. A process as set forth in claim 1 wherein said workpiece includes a preformed cavity therein, said cavity having an internal surface, and wherein said coating material is applied to said preformed cavity surface.
- 8. A process as set forth in claim 1 and further including the step of covering portions of said workpiece to be protected from attack by acid with a protective covering of shellac.
- 9. A process as set forth in claim 1 wherein said step of applying etchant to said workpiece surface includes dipping said workpiece in an aqueous acid solution.
- 10. A process as set forth in claim 1 wherein after withdrawing of said template from said workpiece surface and before said step of applying acid to said workpiece surface, the process further includes th step of cleaning said template to remove coating material therefrom and placing said template against said workpiece surface to remove additional amounts of said coating material from said workpiece surface.
- 11. A process as set forth in claim 1 wherein, following said steps of applying etchant, said process further includes the steps of cleaning said workpiece surface to thereby remove masking material and recoating said surface with masking material.
- 12. A process as set forth in claim 1 wherein said model has a surface contour which is a positive image of the surface contour to be produced in said workpiece and further including the step of casting a hardenable material against the surface of said model to form said template.
- 13. A process as set forth in claim 1 wherein following the step of withdrawing said template, the process further includes the steps of cleaning said template of said masking material, and repeating said steps of pressing said template against said workpiece surface, withdrawing said template and cleaning said template of masking material until said template ceases to remove appreciable quantities of said masking material from said workpiece surface.
- 14. A process as set forth in claim 13 wherein, following said steps of applying etchant, said process further includes the steps of cleaning said surface to thereby remove said masking material and recoating said surface with said masking material.
- 15. A process as set forth in claim 12 wherein said template is comprised of cast room temperature curing urethane.
- 16. A process as set forth in claim 12 wherein said step of applying a masking material to said workpiece includes the application of a coating of re-etching ink to said workpiece surface.
- 17. A process as set forth in claim 12 wherein said step of applying a masking material to said workpiece surface includes the application of asphaltum varnish to said workpiece surface.
- 18. A process as set forth in claim 12 wherein said workpiece includes a preformed cavity therein, said cavity having an internal surface, and wherein said coating material is applied to said preformed cavity surface.
- 19. A process as set forth in claim 12 and further including the step of covering portions of said workpiece to be protected from attack by acid with a protective covering of shellac.
- 20. A process as set forth in claim 12 wherein said step of applying etchant to said workpiece surface includes dipping said workpiece in an aqueous acid solution.
- 21. A process as set forth in claim 12 wherein, following said steps of applying etchant, said process further includes the steps of cleaning said workpiece surface to thereby remove masking material and recoating said workpiece surface with masking material.
- 22. A process as set forth in claim 1 wherein said model has a surface contour which is a negative image of the surface contour to be produced in said workpiece and further including the steps of casting a hardenable material against the surface contour of said model to form a mold, casting a hardenable material in said mold to form said template, and separating said template from said mold.
- 23. A process as set forth in claim 22 wherein following the step of withdrawing said template, the process further includes the steps of cleaning said template of said masking material, and repeating said steps of pressing said template against said workpiece surface, withdrawing said template and cleaning said template of masking material until said template ceases to remove appreciable quantities of said masking material from said workpiece surface.
- 24. A process as set forth in claim 22 wherein, the following said steps of applying etchant, said process further includes the steps of cleaning said workpiece surface to thereby remove said masking material and recoating said workpiece surface with said masking material.
- 25. A process as set forth in claim 22 wherein said templates is comprised of cast room temperature curing urethane.
- 26. A process as set forth in claim 22 wherein said step of applying a masking material to said metal workpiece includes the application of a coating of re-etching ink to said workpiece surface.
- 27. A process as set forth in claim 22 wherein said step of applying a masking material to said workpiece surface includes the application of asphaltum varnish to said workpiece surface.
- 28. A process as set forth in claim 22 wherein said workpiece includes a preformed cavity therein, said cavity having an internal surface, and wherein said coating material is applied to said preformed cavity surface.
- 29. A process as set forth in claim 22 and further including the step of covering portions of said workpiece to be protected from attack by acid with a protective covering of shellac.
- 30. A process as set forth in claim 22 wherein said step of applying etchant to said workpiece surface includes dipping said workpiece in an aqueous acid solution.
- 31. A process as set forth in claim 22 wherein, following said steps of applying etchant, said process further includes the steps of cleaning said workpiece surface to thereby remove masking material and recoating said workpiece surface with masking material.
- 32. A process as set forth in claim 1 further including the step of maintaining the template in alignment with the workpiece.
- 33. A process as set forth in claim 32 wherein said step of maintaining alignment includes orienting the template to the workpiece to thereby linearly and repeatedly contact the same portions of the template and the workpiece surface during the pressing and withdrawing steps.
- 34. A process as set forth in claim 32 wherein said pressing and withdrawing steps include rolling the template across the workpiece surface.
Parent Case Info
This application is a continuation in part from a copending application Ser. No. 30,802, filed on Apr. 17, 1979, abandoned.
US Referenced Citations (10)
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
30802 |
Apr 1979 |
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