Ferg,
That made me tired just reading it. Whew! But, congratulations on the
milestone. Now your canoe has become a submarine... :)
When we bonded the top on A055, last week, we used 6 people. But before
doing the deed, we made a dry run, placing unpulled rivets at strategic
points to make sure the top was aligned properly. The starboard side of
the fin had to be a bit higher, on the flange, than the port, to align
the fin. Once that was done, one person mixed the 420 and flox and
divided the mix into two cups. Two people, starting at the rear of the
fuselage, spread the mix along the flange until they met at the front.
When ready to set the top on, four people, two on each side, lifted the
top on and pulled out on the sides, to avoid letting it touch the
lower. I set three rivets on the firewall flange, then started down one
side for a few feet, then switched to the other side, until I reached
the rear, using only the predrilled holes. Once that was done, I
started setting drill point screws about every 8". Once the screws were
in, we started scraping off the excess, which I applied to the fuel
filler molding, to attach it to the cap. What little was left over was
used to make sure all the seams were filled level. The whole process
took about two hours, including the dry run. I did not use the "splash"
technique on the rear bulkhead or mass balance bulkhead, but laying them
up, the next day, was no problem. Since then, the fin ribs and
sternpost are in, and the rudder and sternpost flanges are trimmed and
ready to attach, permantly. That will have to wait until the fin tip is
bonded. Waiting on the tail strobe to arrive, to insure the wiring is
correct, before doing that.
Again, congratulations on this milestone. It feels good, doesn't it?
Fergus Kyle wrote:
>
>Hello -
>I may be five years late in discussing my experience in the above topic, but
>the sense of progress in what must be the slowest Europa ever to be born is
>driving me to share with any who may be farther behind than I.
>First of all, all the details I set to achieve prior to gluing the top on
>were not met. It became a struggle to do some without leaving out the vital
>actions. As a result I have smooth 1/2" ducting to replace wiring which
>should have gone in, and hope to squeeze other mods and installations by
>wriggling into the abyss.
>Secondly, without the push of a nearby (2 hr) fellow builder, one David
>Miller who is now well ahead of me in completion, I might never have done
>it. That's a given.
>Third, having that morning sanded all potential surfaces, I built two
>containers of 420 at 210gm total each (150 plus 60) and very lightly brushed
>the merest layer of same on the canoe surfaces marked as applicable - and
>noted the time.
>Four, the amount of flox stirred in cannot be easily measured, but I think
>one may safely add more flox than just to avoid slopping from too little.
>This is what David prescribed. I added more to provide more bulk, as some
>layers seemed not to provide the bulk the clearances appeared to need.
>Five, the task needed about 2 hours for the job, although the slopping of
>420 on all surfaces was achieved in under 20 minutes using plastic tubs,
>well stirred with tongue depressors. I had applied the "splash" technique
>(pioneered by paul Stewart I believe and and engendered by GraSing) to the
>original bulkhead arch (which I cut down to a three-inch arc for strength),
>the revised second bulkhead 14inches behind the first which goes the whole
>route from keel to fuse top, the top of the mass-balance tower and the rear
>bulkhead, plus the later model rudder post.
>We then walked the top indoors, held it overhead and lowered it into
>position - badly. The result was some of the 420 was scraped off the canoe,
>both at the widest part (near bulkhead one), at the upper corner of the aft
>joggle (where the top refused initially squeeze wide enough to conform) and
>the 'wings' of the top where they overlie the rudderpost.
>Shocked at the little 'greening' of the canoe overlap (showing where 420 had
>squidged onto both surfaces) - much like you found with the cockpit
>insertion - I assembled a league of drill-screws (those which have a small
>drill, followed by threads incorporated) of the 1/4inch hexagonal drive
>head - #8x1/2inch long. Where green was sparse, I drilled in and cinched a
>drillscrew and was chuffed to see green expand. Unfortunately, this turned
>into a selfserving act of desperation which culiminated in a torrent of
>these devices to whit -121 in all, Some were at 20 inch spacings and some
>2-3 inches apart.
>Six, aftermath.......... In spite of all urging, praying and foul language,
>not all spaces turned green - I would say about 5% or less remains
>improperly gooped. It will be 0% when I add injected 420 pure syrup via
>1/16inch drill holes later today, as the bright backlight inside reveals all
>outside.
>I also kept the tubs and weighed them for residue and unused goop. 31.8gm -
>not bad as potentially wasted material I thought. So the amount used was
>420gm - 31.8 = 388gm.
>
>Conclusions -
>[a] Everything behind the massbalance tower should be in place. I am
>convinced that no human contact with the nether world behind that is wanted.
>[2] Prepare the surfaces for adherence as close to H-hour as you can. I
>used a small electric sander which did the job in about 15 minutes.
>[3] For two people (three if a qualified goop mixer is contracted for)
>two pots of about 200gms or so plus the makings of an additonal 20gms of
>yellow paste should do the job. You may want to make one at a time, or make
>two smaller lots, but the advantage of two daubers at once is a
>time-sensitive thing, and really worth it.
>[4] Give each surface the amount of goop it deserves. If excess squeezes
>out in the event, you should have time to scrape it away and apply it
>elsewhere if you've been timely in application. We found the compound to be
>thickening within the hour, and useful for about another thrirty minutes
>after that - perhaps a bit longer.
>[5] Jam sticks in place insidse to wedge the top 'open' at the flanges,
>tied to pieces of cord which you can yank on to remove when in position.
>Manoeuvre the top cautiously down from above and when both sides are happy,
>plunk into place, giving early priority to the firewall surface. We found
>the upward joggle near the tail to be deficient by about 1/4inch, which may
>not now be the case (kit purchased in 1997).
>[6] Have several smaller projects requiring 420 on standby for excess.
>The sooner the daubing is done, the sooner excess can be redirected and the
>less the waste.
>[7] Do NOT daub the top's flanges. The advantage is the confirmation of
>wetting of both sides of the joggle flange when 420 wets the top and shows
>through visibly. I believe this outranks the pre-wetting of surfaces on the
>canoe.
>[8] Remove the drillscrews after about 7-8 hours. I found few of them
>tainted sufficiently to refuse to undo. The use of 1/4inch hexheads was an
>enormous advantage as the lowly elec. drill made the job a pushover. I
>counted them while watching The Right Stuff on TV.
> It is so visible a step, the triumph of this stage may save my
>marriage - . And we get back half of the guest bedroom for original
>purposes. Review sentence one again.
>Hope this was not too wordy, but that it serves some other poor fish.
>Cheers, Ferg
>
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