Johnson-level-tool-mfg RAS-1 Manuel d'utilisateur télécharger pdf (Page 41)

Thepitchedraftertopcutlayout(atpointCinFigure21)is

thesameasthesupportrafterbottomcutlayout(atpoint

A).Forthepitchedrafterbottomcutlayout(atpointD)

the following equation is used:

BOTTOM ANGLE =

SUPPORT ANGLE + ( 2 x ROOF ANGLE ) – 90°

In our example:

= 57 3/4° + (2 x 33 3/4°) – 90°

= 35 1/4°

Use this equation when the pitched rafter length equals the

support rafter length. We then hold the square tight against

the top edge of the rafter as we did for the top cut and make

amarkatthebottomcutangle(e.g.,at351/4°).Alinefrom

this mark to the pivot point gives us the necessary bottom

cut pattern.

STEP 3. RAFTER PATTERN CUTS:IfFigures20and21are

carefully studied, the rafter pattern cuts can be easily made

followingthepatternsthatwerelaidout.Setyoursawat90°

for all the cuts.

TABLE C

Latitudes for Selected Cities

City, State Latitude N°

Atlanta,GA 34

Bismarck,ND 47

Boston,MA 42

Brownsville,TX 26

Caribou,ME 47

Columbus,OH 40

Fresno, CA 37

Indianapolis,IN 40

Las Vegas, NV 36

City, State Latitude N°

Lincoln,NE 41

Medford, OR 42

Milwaukee, WI 43

Nashville, TN 36

OklahomaCity,OK 35

Raleigh, NC 36

Salt Lake City, UT 41

Tallahassee,FL 30

Toronto, Canada 44

1 2 ... 36 37 38 39 40 41 42 43 44 45 46 ... 66 67

Pas de commentaire

Johnson-level-tool-mfg RAS-1 Manuel d'utilisateur Page 41