SPORT ROCKETRY MAY/JUNE 2022 25
Clamp the marked ring in a vise and
cut in the semicircles with a 11/32 (.3438)
sanding bit using a rotary tool or drill (Fig-
ure 9). e semicircles can be widened and
trimmed with an extra-fine sanding bit to
remove any burs or splinters. A finished
sprocket ring is shown in Figure 10. Glue
the sprocket ring on the flute tube just be-
low the engine block. is will leave room
to tether a harness by threading it through
holes made using a pin vise as shown in
Figure 11. Lastly, brush the entire baffle
with glue for added strength and heat re-
sistance before gluing it into the body tube.
If you make other sized baffles, see
my discussion of vent sizing Peak of Flight
Newsletter #463. If you make templates at
PayloadBay.com but have no way to print
the template, you just lay the ring on top
of your computer screen and mark it as
shown in Figure 12. If you have a circle
template guide, you can lay out the pattern
manually, as shown in Figure 13.
Hopefully you'll find this flute-and-
sprocket baffle as effective and reliable as
I have. But for those of you that still have
some doubt, you can always sprinkle in a
little dog barf. Aer those two catos, I do
it every time.
Figure 7. Parts of a flute-and-sprocket
baffle. e end on the right in this
photo faces the motor.
Figure 10.
Completed sprocket ring.
BT-55
18mm
BT-60
18mm
BT-60
24mm
Figure 8c. Template for BT-60/24mm
baffle sprocket ring.
Created at PayloadBay.com
Figure 8b. Template for BT-60/18mm
baffle sprocket ring.
Created at PayloadBay.com
Figure 8a. Template for BT-55/18mm
baffle sprocket ring.
Created at PayloadBay.com
