Paper-Cutting Machines Part 6

The depreciation that comes from natural evolution due to the constant effort by machine makers to render their product more efficient, and the impossibility of attaching to the older machines new and improved devices, is more serious for two reasons: _first_, that it is apt to be overlooked by the owner; _second_, because of the greater cost of operating the machine, as compared to one of a later and improved design with attachments especially adapted to the particular work in each case, which in some cases permit three, four, five, and six times as much work being produced as can be obtained on a machine not so equipped.

A well designed and built paper-cutting machine will last with care nearly half a century. The prudent manager, however, will find he is obliged to discard most of the machines of various kinds in his plant in much less than twenty years in order to keep pace with the newer shops starting with the advantage of later-designed machines.

SUGGESTIONS TO STUDENTS AND INSTRUCTORS

The following questions, based on the contents of this pamphlet, are intended to serve (1) as a guide to the study of the text, (2) as an aid to the student in putting the information contained into definite statements without actually memorizing the text, (3) as a means of securing from the student a reproduction of the information in his own words.

A careful following of the questions by the reader will insure full acquaintance with every part of the text, avoiding the accidental omission of what might be of value. These primers are so condensed that nothing should be omitted.

In teaching from these books it is very important that these questions and such others as may occur to the teacher should be made the basis of frequent written work, and of final examinations.

The importance of written work cannot be overstated. It not only a.s.sures knowledge of material but the power to express that knowledge correctly and in good form.

If this written work can be submitted to the teacher in printed form it will be doubly useful.

REVIEW QUESTIONS

1. For what is a paper cutting machine used?

2. How does it increase printing output?

3. What is its great importance?

4. What were the first methods of cutting paper, or its earlier subst.i.tutes?

5. How were piles of paper first cut?

6. How was the process improved?

7. Describe the development of cutting machines down to Samuel R.

Brown's invention.

8. Describe that invention.

9. Give the lines of evolution of the cutting machine.

10. What are the characteristics of the best paper-cutting machines?

11. Describe a plough and press cutter.

12. Describe a card cutter.

13. Describe a hand lever cutter.

14. What are the differences between hand and power cutters, and what are the advantages of the latter?

15. Describe two forms of hand-clamp power cutters.

16. What do automatic clamp machines do?

17. How is an automatic power cutter operated?

18. How is continuous running effected?

19. For what are vertical stroke machines used?

20. What results from the great power needed to operate cutting machines?

21. Give some idea of the amount of power needed for these machines.

22. What is the most important part of the machine and why?

23. How do these parts vary?

24. How can you judge the temper of a knife?

25. How can you tell whether a knife has a correct face?

26. How should you hone a knife?

27. What is the rule for the length of the bevel on knives?

28. How is this rule modified by stock?

29. What can you say of the face of the knife?

30. What is desirable in the thickness of the knife?

31. What precaution should be taken as to the setting of the knife?

32. What should you look at if the work is not cut true?

33. Tell all you can about grinding knives.

34. Tell all you can about the use of the hone.

35. What causes are liable to prevent the proper seating of the knife, and what is the result of improper seating?

36. How can the best knives be obtained, and why?