TIPS / WHAT I DID...
- I used the CAD drawings available on Marc's website - CLICK HERE
. Cut the blueprint copies along the lines, then used a
fine point Sharpie to trace the outline of the cut copies.
- I cut all the foams with a utility knife and metal
straightedge. Only needed a few passes on the Seatback and
Landing Gear Bulkheads. For the Last-A-Foam (F22, F22Doubler,
F28, and IP) made multiple passes along the "outside" of the
Sharpie line, then tapped a razor blade with a hammer along the cut
line to finish the cut. Then a few light passes with a Perma-Grit
block quickly shaped to the line. Perma-Grit blocks/tools also
worked great to fine tune Firewall cuts.
- Don't get hung up on making the edges of the bulkheads
"perfect"; you will get them right during the trial fit in
Chapter 6. I would mark the edges per the drawings, then leave a
little extra (1/16" or 1/8") to work with where the part
will meet the Longerons
- Used the "Hinge Method" to 5 minute epoxy bulkhead pieces.
See
Chapter 3 Research Summary for more details
- Used Wayne Hick's method for sliding plies onto work, and recommend
that new builders use it as well. CLICK
HERE to read more about it.
- When working with UNI: use 1/2" masking tape to mark cut
lines. Then cut down center of tape to keep edges from becoming
frayed. Leave taped edges in place, cutting only where needed
when laying plies down. Also, measure carefully to maximize
cloth use. Also ended up doing this with the BID - It seemed to
keep the cloth from deforming while handling.
- If you're new to working with glass, identifying small air bubbles
can be little difficult - especially when everything is
"wetted-out". To me, the small air bubbles below a ply
of glass look like poison ivy blisters. When I find them, I like
to make multiple light passes using the squeegee, working the bubbles
toward the edges with the "grain" of the glass.
- Peel-ply - I seemed to achieve the best results, by laying glass
(per plans orientation), then Dacron peel-ply, then a heavy (~4 mil)
plastic "peel-ply" a la John
Slade technique (see reference towards bottom of page). This
gave me the uniform finish that John mentioned, yet still allowed me
to avoid extra sanding prior to future lay-ups.
- Put some Dacron peel-ply down on F22 over the 3/8" space on
each side of the doubler before glassing on top of the doubler.
- Added .25" to bottom of IP
- Consider waiting on getting an epoxy pump. You may be able to
save yourself some money and aggravation. See
Chapter 3 - Tools
- Fein tool does a nice job of trimming glassed parts if you miss the
knife trim window.
- Used .25"x2'x4' MDF as temporary firewall; marked with W.L. 23,
W.L. 0, and Centerline.
- For the firewall : Made 1.5" square inserts, beveled 45 degrees
on two parallel sides, vs. 1" inserts called for in
plan. If you plan on doing the same thing, then adjust your
order accordingly from the supplier. (I received a 2"x 3"
section of 2024 Alum. from Wicks). Also, for the blind screw
installation, I ground down both sides of the heads and custom cut
each channels to avoid the dreaded "spin" (see below).
- Following tips from others, used highlighter in plans to mark
completed steps.
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NEW TOOLS USED:
Perma-Grit Blocks/Tools, Utility Knife, Jig Saw, 6' Metal Straight Edge,
12" Metal Straight Edge, Hammer, Scissors, Masking Tape, Permanent Marker, Highlighter,
Decimal Tape Measure, Fein Tool, Roto-Zip, Sticky-Stuff
Dispenser*, Detail roller, Hack Saw, Metal Files
* Still debating value
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SEATBACK - Done...maybe
Used a jigsaw (20 tpi blade) to cut 45 degree angle. Varied
from plans by not bringing fiberglass over sides and floxing to front
sides. I did, however bring the top and bottom edges together.
During fuselage assembly, I plan on channeling the sides out before
floxing. As a side note - I also had three "exotherms"
(one pure epoxy, one slurry, one flox) - I'm assuming because I mixed too
much epoxy at a time. Weight - 5.7 lbs (Map pocket not cut). I
am considering rebuilding or modifying the seatback to add a
"pass-through" panel on the passenger side.
NOTES: During trial fit in Chapter 6, this part required the most
adjustment. Leave yourself a little extra where this part, and the
other bulkheads, will intersect with the longerons. Also, keep in
mind (for all parts) that the longerons will not have a 90 degree edge,
but will be rounded slightly. Therefore, the bulkheads should not
have "crisp" corners. I would also just draw the
center map pocket and heat duct cut-outs, and wait to cut them until
Chapter 6.
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F22, F22 DOUBLER, & F28 - Done
The razor tap method worked fine. However, I learned quickly that
you only need to rough cut the high density foam. The Perma-Grit
block takes the edges down quickly, accurately and with no
effort. Varied from plans by glassing the forward side before
doing the aft side. Figured it would be easier to weight down with
the thicker build-ups on each side vs. having the doubler on the top
only. Hopefully that won't come back to haunt me. A little
tip: Put some Dacron peel-ply down over the 3/8" space on each side
of the doubler before glassing on top of the doubler. This will prep
the 3/8" area, and keep the "run-off" epoxy from building
up there.
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INSTRUMENT PANEL - Done
Added .25" to bottom of IP. Note at the time of the photo,
only the center "connectors" had been sanded with the Perma-Grit
block. Glassed on both sides, working on adding stiffeners.
Following the advice of others, I used sealed blocks wood as forms for the
channels. I had some uncertainty about adding the electric channels
on the vertical stiffeners since it appeared that some others had
not. In the end, I went ahead and put them on - figuring I can always
trim them off if the weren't needed.
Added picture: When I have excess epoxy at the end of a lay-up I try to
have small items ready to be glassed/floxed. One of those items are
the leg holes in the IP. I channeled out the foam and filled the
void with flox. After cure, I filed and sanded the edge flush.
NOTES: I used the CAD drawings and added the .25".
When it came time to install in Ch.6, I had to trim most of the excess
back off. But, this was certainly easier than having to add
more. If I had to do it again, I would just glue the basic parts
together, glass both sides, then trace the drawing onto the part and cut
to shape with the Fein tool.
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LANDING GEAR BULKHEADS - Done
I rough cut the foam around the areas adjacent to where the hardpoints
will be be inserted. That way I can adjust for any slight
differences that may occur when I cut out the hardpoints. (Note the
blueprint template to the side) -- One point of interest: the forward
landing gear (designed to be installed at angle) was the one part that the
CAD drawings appeared somewhat different than the M drawings. I
decided to stick with the CAD drawing shape since the dimensions appeared
true and the M drawing contained an interruption. Used 24 plies to
make hardpoints, then used LG Bulkhead foam scraps as supports to control
the thickness while the part was weighted for cure. The finished
part came out a perfect thickness. Note that the picture at left
makes it appear that there are more "dry" spots than there
really are. After cure, used a jig saw with metal cutting blades to
rough cut hard-point shapes. Then I held pieces together in a vise
and used the Perma-Grit tools to finish shaping. Taped the edges of
the finished pieces (like the hinge method) when inserting in the
bulkheads with 5-minute epoxy. Then peeled quickly for a clean
installation.
Side note - Tried masking off the sides of F28 and the LG
Bulkheads to prevent the epoxy and micro run-off from seeping around to
the underside of the part that I was glassing. This didn't work, and
certainly wasn't worth the time.
NOTES - If you are planning to use Wayne Hick's alternate
Landing Gear Cover (as I am), then you may want to add an 1/8th inch along
the bottoms, including the NACA cutout section, of each of the landing
gear bulkheads now. {Do not change the top half of the forward LG
Bulkhead, as it does not come in contact with the fuselage bottom.}
In Chapter 7, you'll find that these bulkheads are designed to be below
the fuselage bottom to create "joggles". Wayne's method
does not require joggles, so the 1/8th will need to be added then if you
don't do it now. Also, if you add the 1/8th inch now, then in
Chapter 6 (Fig. 32) you will need to relocate your block to 3/8th inch
below the scoop cut out to insure that the fuselage bottom mounts flush to
the cutout.
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FIREWALL (S) - Done
Longeron markings on .25"x2'x4' for Temporary Firewall.
After rough cutting Permanent FW with 20tpi jig saw, finish shaped with
Perma-Grit blocks (I LOVE THESE BLOCKS/TOOLS!!). Used clamps to hold
the two "connector" pieces together, and the PG Block onto the
table. This allowed me to get two identical parts. I plan on
using 1.75" round aluminum hardpoints (a la Bernard Siu). After
more thought on the matter, I decided to insert square hardpoints.
However, instead of the 1" x 1" size called for in the plans, I
went with 1.5" x 1.5" squares. This decision was based on
some references that the 1" x 1" inserts had a minimal margin of
error. Additionally, I filed 45 degree bevels on two parallel
sides of each insert. Then I inserted the hardpoints with the bevels
facing aft, resulting in an exposed 1.25" x 1.5" rectangle on
the aft side (see picture at left). Though the plans didn't specify,
I used standard epoxy and flox vs. 5 minute epoxy to install the
hardpoints.
After reading all the comments about the dreaded "spinning"
of the blind screws, I decided to grind the tops of the screws to create a
"T" shaped bolt. I then carved each channel so the now
rectangular shaped tops (see picture at left) had no room to spin.
Hopefully the increased resistance added by the channels, coupled with the
flox, will prevent the "spins".
Note - The CAD drawings show the blind screws (on the two small pieces
that connect the bottom and top firewall) sitting higher than the plans
dimensions. I put them in at this higher location and now I hope
this doesn't come back to haunt me. I looked at Marc Zeitlin's
plane, and it appeared that his were at the higher location. I
didn't see any comments where this caused him problems.
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