When an error is discovered on a drawing while in use in the shop, quite often the error will be marked with a red or yellow pencil. Any such error is usually reported to the supervisor so that corrections can be made on future drawings or on the master drawing of the print being used.

When revisions are required due to changes in design, they are often made on the original copy from which the blueprint was made. In some cases, the original size dimension will be removed and the new one substi­tuted. When such a procedure is followed, a listing of the original sizes will usually be made on the drawing, as shown in Figure 7.16.

FIGURE 7.16 ■ Making corrections.

UNIT 7: REVIEW A

Graph paper is provided at the end of this review for your use.

1. Give three reasons for showing a conventional break on a print.

7. Sketch two other arrangements of the views represented by the following orthographic sketch.

2. Illustrate by a simple sketch one method that can be used to show a revolved section of a length of channel. Use graph paper provided. 3. a. What do the symbols illustrated indicate?

8. Give two reasons for showing an enlarged detail on a print.

3= 'szzzma

b. What material is represented?

9. What linear distances would be shown on a drawing if the following dimensions are drawn to the scale sizes indicated?

4. a. When is an auxiliary view used to show a part?

	Dimension	Scale Size	Distance
a.	2"	2" = 1"
b.	4"	3/4" = 1"
c.	3/4"	2" = 1"
d.	15r	3" = 1"
e.		3" = 1"
f.	%"	2" = 1"

b. Is an auxiliary view dimensioned?

5. Develop an auxiliary view from the sketch shown. Assume that the part is wide.

10. Prepare a simple one-view sketch to show the use of a long break line.

6. a. When two side views are used, describe where they may be located with respect to the front and top views.

b. Show this as a simple illustration on the graph paper provided.

NOTES

ORNAMENTAL SUPPORT POST
QTY 1	ORDER NO. 789	MATL. CRS
SCALE 3/8" = 1”	SPEC
DRAWN BY: L. GRADY	DATE:
DRAWING NO. 7082	TOLERANCE

COMPANY NAME

Refer to the drawing, Ornamental Support Post, page 92.

1. What is the difference between the right and 9. Do any of the tolerances given apply to the

left side views? tapped hole? Give a reason for your answer.

2. Interpret the significance of V2 - 12 UNC.

12 ___________________________________

12 ___________________________________

UNC

3. What structural shape is indicated by the conventional break symbol?

10. Using the scale size given on the print, determine the lengths of the following dimensions:

5"____________________ W_________________

23/4"_______________ V2" ___________________

11. On what parts are conventional break symbols used?

4. What is the significance of the following symbol: ?

12. Why is a conventional break symbol used on the drawing of the ornamental support post?

<C- (5

5. What are the dimensions for distances Q) through ® ?

®______________________

©______________________

®______________________

®______________________

6. What are the largest and smallest sizes permissible for the 0 .500 hole?

Maximum___________________________

Minimum____________________________

(A

13. Identify which dimension on the drawing is a reference dimension.

14. a. What nominal size pipe is used?

b. What is the inside diameter 0 of the pipe? (Refer to Appendix 3.)

c. What material is the pipe?

d. On the print, indicate locations where welds could be applied.

7. What size drill should be used for the tapped hole?

8. What is the maximum permissible overall length of the assembly?

Refer to the drawing, Support Arm, page 94. 1. Name the views that are used to show the part. 11. How many holes are there in the object?

12. What is the largest size that these holes can be made?

2. Which two views are shown as partial or incomplete views?

13. What is the smallest size that these holes can be made?

3. Why are two of the views shown as partial views? 14. At what angle are the holes spaced from one another?

What is the purpose of using a conventional 15. What is the lateral center-to-center distance of break line on the drawing? the holes?

What is the minimum size that the following dimensions can be made: %", 27 ^/2", 23/8"?

16. a.

5. What type of view is shown between the break lines?

. 2712"

. 23/8"

b. What is the decimal equivalent for these dimensions?

. 2712"

. 23/8"

What structural shapes are used for the parts shown in the view between the break lines?

17. a.

6. At what angle are the corners of part to be chamfered?

b. Refer to the section lines and identify the 7. What is the largest angle at which the corners kind of material that is to be used. of part ® can be chamfered?

18. Make a complete bill of materials required for completion of the part. Allow [2]4' for finishing. Assume that the same kind of material is used throughout. Bill of Materials

8. What are the overall dimensions for the pieces that make up part © ?

No.	Material	Size

19. What part is shown as a revolved section?

9. What corners represent line? What are the dimensions for distances (G) through (M? G Cl) (H (g)

Q

UNIT 7: REVIEW D

1. Sketch the development drawing required for making the pats as illustrated by the two views that follow. Use the graph paper provided to sketch your answer.

NOTE: TOLERANCE ON ANGULAR DIMENSIONS ± 2°

2. a. What is the maximum size permitted for the drilled holes?

b. What is the minimum size permitted for the drilled holes?

3. What is the maximum angle of bend for the 45° dimension?

4. What is the thickness and kind of material required?

5. What is the overall length of the material required?

UNIT 7: REVIEW E

4. a. Give a formula that can be applied for

determining the bend allowance for a soft material.

2. Why, in some cases, is it necessary to show a

b. For a hard material.

part of the drawing as an untrue projection?

3. Is it considered a violation of true projection when a revolved projection is used?