Prepare the construction design drawing begins with drawing up a preliminary calculation, whose goal is the definition of parameters most accurately reflects a given shape, purpose product and material properties. A preliminary calculation allows to the drawing set: the width of the main sections (backrest,shelves, openings), width of the sleeve under the armhole, the shoulder girth with wide sleeves and armholes, the posture of the figure.
After measurement of the shape and selection of decorative and constructive allowances need to clarify the width of openings to determine the width of the sleeve at the level of the depth of the armhole. The estimated width of the sleeve in finished form is determined by the formula 
, SROC = (Op.p)/2.
Arm circumference may be equal, smaller or larger model. If the girth shoulder less of the model, the width of the sleeve is calculated according to a standard girth shoulder, if it is more on the actual circumference. Sleeve width, calculated according to standard shoulder girth, does not require modification of the width the arm openings. Increase the width of the sleeve at the level of the depth of the armhole from the calculated 1 cm requires increased openings of 0.7, see Change the width of the openingsproduced by modifying the width of the back or shelves, or both together, maintaining the specified common stock to the chest. By decisioncutter in some cases, the General allowance on the chest can beincreased.

Normal and the minimum width of the openings of the jacket on the model shape 
Size 44 46 48 50 52 54 56 58 
Normal width of the armhole, cm 13,2 13,8 14,4 15 15,6 16,2 16,8 17,4 
Minimum width of the armhole, cm 12,7 13,3 13,9 14,5 15,1 15,7 - -

In the design of the coat, dispensing common stock on the chest, should begin with determination of the allowance for the width of the openings. It needs to be such that the width of the openings correspond to specified normal or minimum width. Allowance to the width of the back at the level of the chest lineregardless of the fashion needs to provide freedom of arm movement and not be less than 1.2 cm, you Should remember that excessive allowance to the width of the chest interfere with the movement of the hands. 
The posture of the figure, i.e., the slouch or pereghibati, is defined by the formula 
OS = Dt.p - DD.with.
For pereghibati figure OS - a positive value, for the figure stooped negative. Oh,and+0,5 is not taken into account. 
Given all of the above, before proceeding to the construction drawings design, you need to do some preliminary work 
to measure the figure for building construction drawings; 
to choose the allowances for free customized fit; 
to distribute a bushel of poluobhvat chest at three sites: back, underarm and a shelf;
to set the desired width of the sleeve under the armhole, compared 
with a calculation and make changes in the width of the openings;
to allocate the total stock of GHGs in the plots; 
calculate the posture of the figure; 
set the rate of planting of N lifts the shoulders. 

LABORATORY AND PRACTICAL WORK 2 

IN a R I a n t 1. To make a preliminary calculation of the prescribed a sequence of three sizes using the drop-down list with specific figures on laboratory practical work 1. 
View product - men's suit of worsted fabric semi-fitted silhouette. 

V a R I a n t 2. To make a preliminary calculation of three sizes of a specific shape. 
Of the product - the coat winter of a woollen fabric pultovoi straight line.

V a R I a n t 3. To make a preliminary calculation of three sizes of a specific shape. 
Of the product - the winter coat of pure wool overcoat fabric. Coat fits over jacket semi-fitted silhouette. The thickness of the insulation strip 0,8 cm 

SELF-assessment 

1. What is the allowance for free customized fit? 
2. What is the total allowance on the chest? 
3. What are the technical allowances and their purpose? 
4. How is the technical allowance? 
5. What is the decorative and constructive allowance? 
6. As indicated by the allowances? 
7. How to use the tables of allowances?
8. The essence of pre-calculation? 
9. What is preliminary design? 
10. Give an example of a preliminary calculation of the design of the jacket. 
11. How is the posture of the figure? 
12. How is the width of the sleeve under the armhole? 
13. What changes are made to the width of the openings, if the shoulder girth of the customer more typical?