User Manual

SER

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UIDE

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(Cont’d)

KEYSTROKE DISPLAY

3. Find Jack rafter lengths and cut angles:

j JKOC 16 INCH*

j JK1 8 FEET 2-3/8 INCH

j JK2 6 FEET 7-7/8 INCH

j JK3 5 FEET 1-3/8 INCH

j JK4 3 FEET 6-13/16 INCH

j JK5 2 FEET 0-5/16 INCH

j JK6 0 FEET 5-13/16 INCH

j JK7 0 FEET 0 INCH

j PLMB 30.26°

j LEVL 59.74°

j CHK1 45.00°

*Note: If display does not read JKOC 16 INCH (the default), then reset on-center

spacing by pressing

1 6 i ß 5

Jack Rafters —

Using Other Than 16 Inch On-Center Spacing

A roof has a 9/12 pitch and a run of 6 feet 9 inches. Find the jack

rafter lengths and cut angles at 18-inch (versus 16-inch) on-center

spacing. The on-center spacing is used for both regular and irregular

jack calculations.

KEYSTROKE DISPLAY

1. Enter pitch, run and spacing:

o o 0.

9 i p PTCH 9 INCH

6 f 9 i R RUN 6 FEET 9 INCH

1 8 i ß 5 OC STORED 18 INCH

2. Find Jack rafter lengths and cut angles:

j JKOC 18 INCH

j JK1 6 FEET 6-3/4 INCH

j JK2 4 FEET 8-1/4 INCH

j JK3 2 FEET 9-3/4 INCH

j JK4 0 FEET 11-1/4 INCH

j JK5 0 FEET 0 INCH

j PLMB 36.87°

j LEVL 53.13°

j CHK1 45.00°

3. Reset on-center spacing to default 16-inch:

1 6 i ß 5 OC STORED 16 INCH

4065UG-E-B 6/9/04 1:50 PM Page 67