7
TRADITIONAL BENDING TECHNIQUES
Helpful Hints for Trim Work
Material: Aluminum coil 4
3
/
4
inches
wide x the desired length. (For
practice, use only about 1 foot
length coil)
Finish
Side
Up
Finish
Side
Up
Finish
Side
Down
2"
1
3
2
1
1
/
2
"
1
/
2
"
3
/
4
"
2"
2
3
/
4
"
4
1
/
4
"
2"
2
3
/
4
"
4
1
/
4
"
12"
4
3
/
4
"
Mark with pencil
Then snip in from
edge 1/4"
1
2
2
3
1
2
When breaking material, bending to just 45
°
will avoid round-
ing the edge. The
Pro Cut-Off was designed to safely and
easily cut your material in seconds. See page 12.
5.
For bending, follow the suggested sequence of bends on
pages 8 and 9. For actual bending techniques see “Bending
the Roof Drip Edge” below.
6.
Don’t fit your trim parts too tight. This will complicate the joints
where parts overlap. A one inch (1") lap joint is enough to
allow for expansion and contraction.
Trim should be lapped
so that laps are facing away from traffic areas.
7.
Try to nail the trim parts on an area that will make the nails
less conspicuous. Fasten at laps. When face nailing, use just
enough nails to secure trim; DO NOT DRIVE NAILS TOO
TIGHT!!
8.
Remember, when designing shapes you are hanging a cover
over the wood parts, not laminating a skin-tight surface. This
is called “Floating Your Trim”. Allow for irregularities in the
wood because your formed trim shapes are straighter than
the wood trim moldings or boards you are covering.
9.
With practice, you’ll learn to overbend or underbend certain
sections to achieve a pressure fit of your trim parts which
will, in turn, require fewer nails and give your job a more
wood-like appearance.
10.
Hemming (making a 180
°
bend on the edge of a sheet) will
give your shape a “Factory Edge Look” and will stiffen the
entire trim piece to help eliminate “oil canning”. See page 6.
1.
Measure the total length of the particular trim area to be cov-
ered and divide by the length of your Bender to determine
the number and length of trim pieces needed.
2.
Determine the dimensions of each section of the desired trim
shape by measuring that particular profile to be covered. As
an aid, make a pattern out of a 1" strip of coil to get your
exact profile.
3.
Transfer the dimensions in Hint #2 to each end of a piece of
trim coil by making a
1
/
4
" slit in the metal with a pair of shears.
These marks now become the bending points and makes
the bending marks visible from either side. On longer lengths
fold the coil over as shown and snip both ends at once. This
saves time and ensures accuracy. The
Tapco Pro-Filer was
designed to make this time consuming part of your job easier
and more accurate. See page 13.
4.
Lock the pre-marked coil blank into the Bender with the cut
marks located directly under the outer edge of the Stainless
Bending Edge. Lock Bender. To cut off the coil with a razor
knife, score the metal against the Stainless Bending Edge.
Now bend the metal up and push back down by hand until the
exposed section breaks off. It may require 2 or 3 repetitions.
1.
Numbers show the sequence of the bends; thus,
would be the first bend, the second bend, etc.
2.
"Finish Side Up" indicates that the finished or
exposed side of the trim is to be put into the Bender
FACING UP.
3.
"Finish Side Down" indicates that the finished or
exposed side of the trim is to be put into the Bender
FACING DOWN.
4.
The symbol
*
means the bend is to be 180
°
.
Roof Drip Edge
*
1.
This shape is basic to all the other shapes contained in this
manual. Practice this shape before you proceed with the other
trim pieces illustrated on pages 8 and 9.
2.
To begin, cut off a piece of coil 4
3
/
4
inches wide by about 1
foot long (As shown at right.)
3.
Mark your coil with a pencil at 2", 2
3
/
4
" and 4
1
/
4
" on both ends.
Then snip these marks in about
1
/
4
" (so they will be visible on
both sides of the coil).
4.
Put your coil into the Bender with the Finished Side Up. Bend
is the 2
3
/
4
" mark, so lock the Bender on the mark; then,
bend 90
°
.
5.
Remove the coil from the Bender. Bend will be at the 2"
mark on the coil, so now put the coil into the Bender with the
Finished Side Down. Lock the Bender on this 2" mark. Note
that Bend shows the symbol
*
which means the bend is to
be 180
°
. Bend this as far as it will go (about 165
°
). Then pro-
ceed to hem it in the Bender as shown on Page 12 in “Basic
Hemming and Folding.”
6.
Now to Bend put your coil back into the Bender Finished
Side Up and lock on the 4
1
/
4
" mark. Bend this approximately
45
°
as shown to complete the shape.
Bending the Roof Drip Edge
(General instructions for all examples)
