TWDB Thermofit Cut Lengths

Cut Lengths for TWDB Thermofit Wraparound Duct Bands

     Ok, everything I will share here is printed on the actual TWDB boxes themselves (whether 3" wide or 4" wide).  No need to take notes.  When your TWDB arrives you will have all of this data and info right at your fingertips (literally).

TWDB Installation Instructions:
Materials and Equipment required:
- TWDB
- High temperature closure tape (included in the TWDB package)
- JS2601 torch or equal
- Propane tank
- Heat resistant work gloves

1: Join duct sections using internal couplers or crimped end male female type connection.  Apply sheet metal screws.  2 screws 180 degrees apart are usually sufficient.
2: Wipe joint area to remove foreign materials.  Preheat joint to remove moisture and burn off surface oil that may be present.
3: Cut TWDB to appropriate length (see sizing chart).  Center TWDB and wrap around duct joint.  Using the supplied closure tape, secure the loose TWDB end by taping in place across the width of the overlap.
4: Adjust torch to provide soft billowy flame.  Heat TWDB uniformly.  As heat is applied, the TWDB will chrink and bond to the duct to form a pressure tight seal.
5: With gloved hand pat down overlap area to ensure proper adhesion.
6: Recovering is complete when the TWDB is in 360 degree contact with duct and the molten adhesive is visible at both ends. 

The following chart is organized:  Duct Size / TWDB Cut Length
2" / 9"
3"/ 12"
4"/ 15"
5"/ 18"
6"/ 21"
7"/ 24"
8"/ 28"
9"/ 31"
10"/ 34"
11"/ 37"
12"/ 40"
14"/ 46"
16"/ 53"
18"/ 59"
20"/ 65"
22"/ 72"
24"/ 78"
26"/ 84"
28"/ 90"
30"/ 97"
32"/ 103"
34"/ 109"
36"/ 115"
38"/ 122"
40"/ 128"
42"/ 134"
44"/ 141"
46"/ 147"
48"/ 153"
50"/ 160"
52"/ 166"
54"/ 172"
56"/ 178"
58"/ 185"
60"/ 191"
62"/ 197"
64"/ 204"