RotorWay International
Exec 162F Construction Manual
Section 1
Page 4
Rev. 1 8/00
4. WORKING WITH 4130 STEEL
A. Bracketry
1. Cut brackets to size using the templates supplied. If there is a grain direction specified on the template, paste the
label on the material in that orientation.
2. Use a 24 teeth per inch hack saw blade or a low speed band saw to cut out bracketry. Radius all internal corners
smoothly with a rat-tail file. This will help prevent cracking during the bending operation.
3. If a bracket is to be bent, hold it in a vise with aluminum jaws; or bend a piece of scrap, then bend the bracket over
the scrap material. As you hammer the bracket around the scrap, it will follow the radius of the scrap piece. Check
for cracking after you have formed the bend. Heat may be applied during the process for brackets over 1/16"
(.062") in thickness.
4. It is good practice to remove all sharp edges when working with sheetmetal. Various types of deburring tools are
available, or use a file or sandpaper.
5. WORKING WITH ALUMINUM
A. .025" aluminum may be cut with left and right hand metal cutting shears. .050" may be cut with a band saw or hack
saw. Remove all sharp edges after cutting.
B. The same rules apply for bending aluminum as for 4130 steel. If the radius is too sharp, the material may crack. .025"
aluminum may be clamped in a vise against a board and bent around the end of the board. Sufficient sheet metal has
been supplied in the kit; take care to position the templates in such a manner that you use up the material effectively.
6. WORKING WITH PLEXIGLASS
A. Use caution when handling the plexiglass windscreen. The edges of the windscreen should be immediately sanded
smooth to prevent possible cracking during the handling process. A file or air sander may be used for rough grinding,
then finish by hand using 80 to 100 grit wet/dry sandpaper. During any sanding process, be careful to support the
material adequately in the area in which it is being worked. Be especially careful if you are using an air sander (2" to
3" diameter recommended).
B. Do not remove the protective film coating from the windscreen, doors and other plexiglass components until all work
on them has been completed.
C. When drilling cleco holes in plexiglass, try using a Uni-Bit or step drill. This type of drill is less likely to cause the
material to crack.
D. Before the windscreen is final installed, the screw holes must be drilled oversize (using a 5/32" drill) so that the
windscreen is able to move slightly. There should not be any stress on the windscreen. The fasteners that hold the
windscreen should be snug, not over tightened. They should be secure and just able to be turned with a screwdriver.
E. Clarity may be maintained in the windscreen by frequent polishing with mirror glaze.
F. If a crack begins to form in plexiglass, immediately drill the end of the crack with a small drill (about 1/16" diameter) or
the crack will propagate like a zipper.
7. WORKING WITH FIBERGLASS
WARNING: WHEN WORKING WITH FIBERGLASS, MAKE SURE THE AREA HAS ADEQUATE VENTILATION.
A. Locate additional supplies, including: acetone, rubber squeegee, 1" to 2" wide brushes, and plenty of rags. Rubber
gloves and eye protection should also be used.
B. Prior to fiberglass application, prepare all surfaces by sanding and cleaning with acetone.
C. MIX 20 drops of catalyst with 4 oz. of resin. The hotter the outside temperature, the less catalyst is used. The resin should
not take more than 35 minutes to “kick”. Test a small sample to get a feel for what works best (20 drops = 1/2cc).
D. All components which are fiberglassed to one another will use a layer of mat or cloth to bond the two surfaces
together. Materials provided include 2 oz. mat and cloth. These may be used in two or four ply thickness as appropriate
(one mat or one cloth equals one ply). Do not start any fiberglass process unless you have some acetone and rags on
hand for clean up.
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