Place the cowl in a corner of a room.
Draw a horizontal line on the wall up from the floor the same
distance from the firewall as the Schertz beam will be using
a carpenters level.
Mark off the line every 4 or 5 inches.
Use one of those construction lasers that project
a beam perpendicular to the wall. Use a magic marker
to mark the laser spots on the cowl.
Measure the distances from the wall to the magic marker spots
on the cowl and you now have the coordinates of the cowl curve.
Should only take a few minutes.
Send me the numbers and I can do a 3D of the cowl if I have the
shape of the firewall and the size of the spinner.
Paul Lamar
Paul,
I'm guessing this instruction was for me since I made the mount request
to Jerry. I've already started working on this by removing the nose gear.
I retrieved the lower cowl from its storage area and attempted to fit it to
the fuselage. I noticed a scribe line on the cowl so the 36" figure I gave
includes this and probably shouldn't since you typically have to trim scribe
lines. This brings the cowl length down to about 35". I do have a laser on
a tripod but it doesn't project a line only a spot. I was planning to mount
the cowl on the plane, level the plane and then use a straight edge across
the top to bridge from side to side on the top of the cowl. Starting at the
firewall, I could measure from the bottom of the straight edge (which is the
top of the cowl) and give you a "depth" every few inches from left to right.
Then move the straight edge forward 3 or 4 inches and repeat until I reach
the very front of the cowl. This should map the interior of the cowl
nicely.
As for measuring up from the firewall to the same distance as the beam,
I don't know how far that is. Somebody will have to let me know, if it is
important. Right now, mapping the cowl for 3D seems the way to go.
Perhaps I can do this tomorrow. We'll see. There has been a great deal
of foul weather locally today and even worse is predicted tonight. A small
town about 10 miles away was devastated by a tornado this afternoon
(official estimates indicate 50% of the town is destroyed). They may need
volunteer help and if so, this will wait.
Charlie Smith
KIS Cruiser 4021
The distance is 16 inches back from the cowl prop flange opening or 21
inches up
from the floor. Your cowl sounds a bit shorter than Bill's and mine. Mine
is at
the hanger. Bill what is the lenght of your cowl?
Paul Lamar
I will double check today when I get to the hanger, however I believe that
it is the same as Charlies.
I have NOT trimmed to the scribe line, because I am locating the oil cooler
below the beam mount, and trimming the cowling will shorten the cowl even
more. Charlie, you need to provide room for clearance between the accessory
drive pulley and the nose gear also.
Charlie, I am not understanding the measurement technique you are
describing. If you get the "depth" from the lower cowl joint line, you also
need to know how far from the centerline of the cowl the point is. How will
you determine that?
Bill Schertz
Sounds short. That nose gear strut is tight with the back of the engine. Might
be wise to add a bit of foam around the spinner and move the engine a few
inches further forward. Either that or add a strip of FG on the back edge
of the cowl.
Paul Lamar
Bill,
All I did was lay the bottom half of the cowl upsidedown on the floor (mating joggle for the top half of the cowl touching the floor), put a straight edge on the floor along the firewall mating end and another on the floor along the spinner end, move the cowl out of the way and measured between the two straight edges.
Paul, I did go ahead and place the lower cowl on the firewall and began taking measurements with reference to the aircraft centerline. Beginning with the third set I noticed the left and right edges were not symmetrical about the centerline. By the time I have moved out 20 inches from the firewall, the left side (facing the firewall) was 3/4 inch closer to the centerline than the right side. This probably indicates the cowl needs trimmed along the back to make it square. Would this be close enough for the model or should I correct it and start over?
Charlie Smith
KIS Cruiser 4021
Those are interesting measurements but I need a cross section through the area
where the Schertz beam will reside. The rubber bushing holders could interfere.
You need to fit top and bottom together and set it in the corner of a room.
with the flat surface of the top of the cowl flush with one wall.
Then come up 21 inches from the floor and draw a horizontal line on
the other wall. Mark this line every four inches. Use the perpendicular
tape measure to record the distance from the wall to the cowl surface.
Paul Lamar
The AirCraft Rotary Engine NewsLetter. Powered by Linux.
ACRE NL web site. http://home.earthlink.net/~rotaryeng/
Copyright 1998-2003 All world wide rights reserved.
