Small Engine Mounting; Bypass Duct - Carf-Models Ultra Flash Instruction Manual

12mm wide plywood strip included in the kit, sand to required thickness, and glue to the
mounting rails with CA (photo above).
Normally the turbine will need to be mounted right at the front of the engine mounting rails,
against F5, so that the back edge of the outer casing (the 'chromed' part on Jetcats') is about
15 - 18mm in front of the front edge of the carbon bellmouth and F6 bulkhead.
Make sure that the turbine is aligned exactly central with the thrust tube and then drill the
Ø4mm mounting holes, using the mounting bracket as the template. Remove the mounting
bracket and open the holes up to Ø 5.5mm for the T-nuts. Using one M4 bolt and a large
washer, pull each T-nut into the mounting rails just a little, with a drop of 30 minute epoxy on
each. Then re-install the engine and mounting bracket and tighten all four M4 x 16 bolts tightly,
which will make sure that the T-nuts are perfectly aligned when the glue has cured.
Final vertical alignment of the turbine can be adjusted by using 1 or 2 of the extra M4 washers
supplied, glued to the plywood with a drop of thick CA.

Small engine mounting:

If you chose a turbine at the smaller end of the recom-
mended range you will find that the plywood mounting rails
are too far apart for the turbine mounting bracket, and we
include adapter plates to solve this.
In the milled wood pack you will find 4 plywood rectangles
80mm long x 30mm wide (2 @ 3mm thick, and 2 @
1.5mm thick). Glue one of each thickness together with 30
minute epoxy to make 2 adapter plates at 4.5mm thick.
Use the supplied M4 x 16 bolts and T-nuts (as described
above) to fix these new plates to the original plywood
engine mounting rails to reduce the width between the
mounting rails, and also raise them 4.5mm to centralise
'Jetcat type' mounting brackets in the bypass duct. In the
hardware are 4 extra M4 bolts and M4 locknuts you can
use to secure the aluminium engine mounting bracket to
the small engine mounting plates.

Bypass duct:

The carbon bypass duct needs final trimming to suit your
engine mounting bracket and installation, and the photos
here show it trimmed for a P120. The fine lines moulded
into the parts to guide your trimming and sanding are for
this engine size. If fitting a smaller engine you will need to
adjust these to suit.
Note: The 'upper' bypass half is the one that will be at the
top when the fuselage is the correct way up, but all the
next section is done with the plane upside down - working
thru' the hatch in the bottom of the fuselage. In this case
the 'cover' is the lower part of the bypass. Please don't get
confused !
Take the 4 small pieces of milled 3mm ply and glue togeth-
(below) Small engine mounting
adapters are made by gluing the
milled ply 3mm and 1.5mm rectan-
gles together with 30 min epoxy.
(above & below) Upper bypass
ducting is secured to these 2
blocks with M3 bolts & T-nuts.
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