2015 - Back to the Firewall

It's only been 7 years.  OK, I've been working a Cessna 140 project and a 1926 WACO NINE project while the Fly Baby sat collecting dust and filling up the attic.  I've realized the plane will be 50 years old in July 2016.  I need to get this back in the sky, and I need the attic space to assemble the wings for the WACO.  The Cessna long ago moved to a tent in the driveway but there is only so much room in the attic.

 I realized I needed to be able to easily move the engine out of my way and back as I work on the firewall.  I don't really have room for an engine hoist.  I have this old come-along to lift it with.  I screwed 4 eye bolts into the rafters to hold pipes for the come-along to hang from.  With caps on the end of the pipes they won't slide out of the bolts when moving the engine.  The hardware store had some nylon tube fittings which work great for bearings.  You have to lighten the load a bit for them to slide on the rough galvanized pipes, but it works to quickly move the engine to the firewall or out of the way.

 I did find it worked better if I balanced the engine with small ratchet straps at each end.  It was easier to align the engine mount with the bolts.

You can see the old holes in the wood former.  I wanted to use as many of them as possible rather than make more holes just to locate things a little better.

 Originally we stuffed several items through one hole and used putty to seal it.  I wanted a grommet on each item so I located more holes to make it all work.  I also wanted cabin heat so I needed holes for it.  I know it's open cockpit but a few degrees warmer can make a much nicer or longer winter flight.

 All the hole where a grommet was used were drawn to show the hole and the outside of the grommet.  It helped me keep it clear what I was doing at each hole.  I also made notes of what was going through the hole because each grommet needed to be sized to fit tight to that item.

Holes were drilled as large as could easily be done and the filed to size with progressively larger files.  The holes were then deburred to protect the grommets.

 With all the holes done, the firewall goes back on the fuselage to mark the new holes needed.  The curved line is the bottom of the tank.  The rudder pedals were also marked to prevent locating things in bad locations.

 The new holes were cut in the wood and sanded.  All the bare wood was varnished.

The large washers on the engine mount bolts are to help keep the mount from compressing the plywood.

The firewall with grommets.  I plan to make metal covers to seal the grommets against fire, and do fire protection for the hoses.