The cradle has been the subject of a recent thread about bolt hole
elongation started by me.
If you take a look in the archive, you will find that everyone who has their
own website has experienced some form of bolt hole elongation. Tony K had
his rear bolts rip out. I've also talked with Bob Berube, who came up with
the design along with Jim Thursby. The following should be mentioned RE:
this design -
0. The cradle does not inherently straighten things out. You have to level
the fuselage first. It will hold level, but
you will need to set the position of the bondo pads with the top in
place to get the right widths at the rear
mounts. It doesn't do anything to restrain the tail cone from twisting.
1. The fuselage tub must hang to allow the cockpit module to achieve best
fit. This is what the factory cradle does.
Chuck's design is very neat and clever, but may not allow the proper
shape when fitting that module.
2. The fuselage tub does not have to hang EXCEPT when fitting the cockpit
module. Some form of foam support
underneath the tub at firewall, seat back, and rear mount points is OK,
and desirable, because -
3. The bolt holes WILL elongate if you use 1/4" bolts, which most people
seem to have that have had problems.
Bob and Jim recommend 3/8", with pads to spread the load made out of
bondo. IMHO, the bolt holes will
elongate anyway over the course of a typical build - 2 years. Bob and
Jim haven't had problems with elongation,
but I wonder if they've ever had a fuselage in a cradle for more than 6
months.
4. The rear mount points should carry more load than the front. They'll rip
out first. It may not be necessary to fit a
support at the tail cone, but given the recent comments on tub twist,
perhaps it is a good idea. Makes for a real
pain in moving about the build space, though...
5. The front horizontals don't serve a structural purpose other than to
stiffen the uprights - remember, the fuselage
HANGS - so I just used 45degree braces.
6. Wood is cheap. I just used an 8' long frame and vertical supports
instead of angling them. If you place the front
supports outboard of, and the rear supports inboard of, the 2x4 frame
piece, you'll be within a 1x6 of perfect fit.
7. Drill the holes through the doubled sections of BID. Stronger that way.
All my opinions except where noted - I'm supporting the fuselage with
removable pieces that attach to the uprights and allow the tub to hang when
the time is right. I'd feel better if Andy Draper would weigh in on the
twist issue and the "misplaced" torque tube crosshairs issue, though...
Shaun
A207
----- Original Message -----
From: "Rob Waters" <robw@iprolink.co.nz>
Subject: Re: Fuselage Cradle
> Cleve,
>
> Have a look at the cradle on Chuck Popenoe's page (see link below). This
> is the one that I am using, and I believe that it's much better than the
> design suggested in the manual. With this cradle, one person can easily
> roll the entire fuselage to 60 or 90 degrees for better access to the
> underside, plus the general support provided is very good, with no need
> to drill holes in the fuselage.
>
> http://members.bellatlantic.net/~cpops/cradle.htm
>
> Rob Waters
>
> kit 437
>
> clevelee@cswebmail.com wrote:
> >
> > Europa's pre-delivery information came with a sketch of a fusulage
cradle that is constructed from 2x4's and suspends the fuselage from 4
bolts. Does anyone have any experience with this design - and will it pull
the fuselage into shape?
> > Any mods to it that should be considered?
> >
> > Thanks,
> > Cleve Lee
> >
>
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