This photo is of the prototype during the
earlier phases of construction.
March 23 2012 2.0hrs - 1586.0 total. Marked
and sanded D ribs so outer profile matches spar
flanges. Trial fit elevator on stab again. I can at
least get the elevator close enough to the stab
to get the hinge pins in now, but the D ribs still
bind creating a very small range of motion for the
elevator. Went back and looked at photos of
Terry's and Steve's projects and then at photos
of original MKIs in museums. The real Spitfire's
have a very small gap between the elevator and
the stab, and the notches for the hinge points
aren't visible unless the elevator is deflected
pretty far. On the Tally-Ho the gap is huge and
the hinge openings are very visible - at least on
the Terry's. They look a little smaller on Steve's. I
think its because the Tall-Ho stab has quite a
taper as you move outward on the stab, where
the original appears to have had an almost
constant thickness. Either way, I want to keep
the gap as small as possible.
|Original MKI stab and
elevator showing very
small gaps between
surfaces and no hinge
point notches unless
surface is deflected.
gap and large
|My elevator mated to the stab without the D ribs in place. Stab
skin overhangs have been trimmed back all around, and I would
like to keep them where they are, but I can't get the D ribs in
place with them overhanging so far. Still working on this.....?
|Overhangs with another
1/4" removed all around
and gap 1/8" narrower after
removing spacing washers
from behind eye bolts.
March 24 2012 5.5hrs - 1591.5 total. Made up a sheet with all the angles, gaps, pivot points etc
and used full sized D rib templates to try to see what was going on. Also went back and looked at
photos of Steve's project again. Removed the spacing washers behind the hinge eye bolts which
reduced the gap between the stab and elevator by about 1/8 inch. This changes the pivot point a
little and changes the angles a little in the right direction. Also trimmed about another 1/2 inch off all
the trailing edge overhangs. Also went and picked up some shorter hinge bolts that will fit between
the D ribs easier and low profile castles nuts to go with them. Cut notches for D rib #4 on each side.
Getting closer to getting this figured out.
March 25 2012 3.5hrs - 1595.0 total. Marked and sanded D ribs to match edge of spar. Glued on
all D ribs except 1 and 2 on each end. Glued on inboard end-caps on elevator. Sealed leading edge of
|D ribs except 1
and 2 on each
end glued in,
March 30 2012 2.5hrs - 1597.5 total. Removed clamps, sanded
down inboard endcaps. Cleaned up shop. Put outermost hinge eyebolts
in place and mounted elevator on stab with just those hinge points to
check clearance of gap.
March 31 2012 4.5hrs - 1602.0 total. Re-measured gap and
overhang on plans again. Got out photos of Terry's and Steve's
projects and was able to verify that I really did need to trim back the
overhang a little more. Very reluctantly took off another 3/8" on all
trailing edge overhangs. Trial fit the elevator again. Removed and added
one washer behind hinge eyebolts spreading the gap almost another
1/8". Shaped D ribs 2 on both sides. Removed some material from the
inside of the corner molding under the trailing edge on the outer end
of the stab - where it binds against the elevator at full deflection.
Measured and started cutting out 1.5mm plywood that wraps around
leading edge of elevator D ribs. Have both pieces rough cut, but need
to steam them to be sure they don't crack during fitting.
April 1 2012 5.0hrs - 1607.0 total. Steamed both D rib skin sections and clamped in place to cool.
Went back after a few hours and removed the skins. Had to come up with new bench bracket to
allow stable clamping of elevator to bench while still allowing full access to area for skins. Aligned port
skin on elevator, clamped in place, installed alignment pins. Located and rough cut port hinge point
|Elevator leading edge
skins just steamed and
clamped in place to cool.
|Port skin aligned
April 2 2012 0.5hrs - 1607.5 total. Noticed that the way the plans show to shape the trailing
portion of the D rib skin is different from the original Spitfire. Started drawing out the original pattern
to see how hard it would be to do. Lightly sanded the hinge notches that were rough cut yesterday.
Removed port skin from elevator. Its much more flexible with the notches cut out. Got a nasty
splinter and spent about a 1/2hr digging it out then got a couple of phone calls so gave up for the
April 4 2012 1.5hrs - 1609.0 total. Put SB skin on, positioned, put in positioning pins, cut hinge
point notches, sanded them down a little. Marked the back side of the skin for gluing lines.
April 5 2012 3.0hrs - 1612.0 total. Removed SB skin, trimmed edge where it overhung control horn
in the center. Mounted elevator on stab...again. Sanded top sides of D ribs to provide clearance
based on estimated skin contact areas. Marked bottom edges of D ribs. Removed elevator, mounted
to bench. Sanded marked bottom edges of D ribs along with top side and overall shaping of the D
ribs. Also sanded down base of horn rib to reduce thickness of elevator at that point. Re-mounted
elevator, sanded some more, found elevator binding on fuselage because it had settled. Shimmed up
trailing edge, eliminated that binding spot. Removed elevator again, added another washer to increase
gap width. Tested clearances. Removed elevator, removed both spacer washers leaving only large
970 washer. Re-mounted elevator. Definitely works better with a smaller gap. Will need to remove
some material from the leading edge of the D ribs. Am slowly getting there with this gap issue!
April 6 2012 - 3.0hrs - 1615.0 total. Removed elevator again. Sanded down top of D ribs by about
1/8" and shaped ribs to rough D shape again. Remounted elevator. Looks pretty good. Tried
removing last washer behind eye bolts to reduce gap even more. This helped with the endcap
clearance even better. Removed and replaced elevator several more times during subsequent steps.
Marked stab encaps where they rub. Ground down a triangular indentation on the rear part of the
stab endcaps to prevent rubbing. Works very well. All D ribs are the right length and width now, but
due to the rough nature of the size reduction sanding they are not shaped very nice. Used compass
and circle templates to mark all the D ribs so they can be shaped to a nice curve for gluing on the skin.
|Looks like the secret to getting the
elevator and stab gap correct and full
range of motion for the elevator is to
make the gap as small as possible - 1
7/8" for my project - and cut these
grooves into the stab endplates.
April 7 2012 4.5hrs - 1619.5 total. Shaped all D ribs as marked yesterday to get symmetrically
curved leading edge for skin to seat onto. Glued in D ribs 1 & 2 on each end of elevator spar. Finished
sealing all D ribs and all inside surfaces forward of the elevator spar including endcaps. Used extra
thickened glue to seal gaps around elevator trim tab horns and screws on both trim tabs. Put one
coat of sealer on all outside surfaces of stab (except spar which is already done with two coats).
April 9 2012 3.0hrs - 1622.5 total. Turned elevator over on bench and sanded ALL surfaces and
glue joints in preparation for sealing. Actually finished it. Ready for sealing now. I want to put on two
coats so I'm going to need to wait till I can put on the first, and then put on the second between
about 8 to 12 hours later.
April 12 2012 2.0hrs - 1624.5 total. Made up some blocking pieces to go in the elevator spar to
add extra strength next to the elevator horn. Sanded the edges off all the surfaces that will be
covered by fabric - per the fabric manufacturers instructions.
|Blocking pieces ready to
be glued in place in spar.
April 13 2012 3.0hrs - 1627.5 total.
Glued in spruce blocks. Put first coat
of sealer on all unsealed areas of
elevator. Thats a lot of surface area!
Took 4 batches of epoxy.