Archive for April, 2011

Started F-704 Bulkhead – 2.5 hrs

April 29, 2011 Leave a comment

Friday Apr 29, 2011

Tonight I started the Center Section. I confess I spent the first half hour just studying the drawing to try to understand where and how many snap bushings to install. The first step was to measure and drill two holes on each F-704 bulkhead near the centerline for two SB625-7 snap bushings.

Center snap bushings

Then I located two more at pre-drilled “starter” holes near the outboard edge of each end. One of those is right up against the flange of the adjacent part and you have to grind off most of the flange of the snap bushing to make it fit. Seems weird but OK.

Outboard snap bushings

Then I started on the Control Column Mounts which are partially pre-made. The builder has to cut part of the flange off to reduce weight and drill the mounting holes. Here I have marked the parts for the material to remove and drill holes at the inside corners to make it easier to cut it out on the band saw.

F-633 Control Column Mounts

After a little cutting, grinding, buffing and polishing I ended up with this.

F-633 modified

Categories: Bulkheads, Fuselage

Dimpling the Firewall Parts – 2 hrs

April 26, 2011 Leave a comment

Tuesday Apr 26, 2011

I dimpled and machine countersunk the fuselage parts tonight. The dimpling of the stainless steel bulkhead was easier than expected. The DRDT-2 works as well on this material as aluminum. I took my time to remove each stiffener and reinforcement plate and machine countersink the right holes to the right size and avoid mistakes here.

Firewall dimples and countersinks

Then I cleco’d it all back together. This is ready to clean and prep for assembly. After some research and deliberation I am planning to alodine the aluminum parts before final assembly. I don’t want to prime or paint these parts because of the risk of toxic fumes in the event of an engine compartment fire but I don’t want to leave the parts bare. Aluminum indirect contact with stainless steel produces a pretty high galvanic couple which could lead to corrosion, especially under humid conditions. Alodine provides a protective barrier and makes the aluminum surface much more corrosion resistance than the bare surface. It also provides a surface that I could easily prime and paint later if I change my mind.

Firewall dimpling and countersinking completed

Categories: Firewall, Fuselage

Firewall Parts Deburring and Deglossing – 2 hrs

April 25, 2011 Leave a comment

Monday Apr 25, 2011

No photos today. Time spent deburring and deglossing firewall parts. Boring stuff.

Categories: Firewall, Fuselage

Match Drilled Firewall – 2 hrs

April 24, 2011 Leave a comment

Easter Sunday Apr 24, 2011

The first task today was to make the F-601P spacers and that meant determining what stock to use for these parts. The drawing just says make from .062 thick 2024 Alclad. After looking high and low I found several pieces of .062 thick sheet but eventually I was able to correlate those with other parts based on notes in the bill of materials. Finally I found the material in one of the many bags of small parts (1982-1) already cut to near net size. After a little trimming, smoothing and rounding they were ready to match drill to the firewall.

Match drilling the firewall parts is a bit slower than normal because the bulkhead is stainless steel and you need to lube the drill bit and feed it a bit slower than all aluminum parts. I use Boelube which seems to work pretty well. Here is one of the spacers which extends out from under the steel corner weldment.

F-601 P spacer installed and match drilled

The F-601 E stiffener is made from a 5 foot long piece of angle stock (as best I can determine). It is 8 inches long and chamfered on each end. Here it is match drilled to the firewall.

F-601 E stiffener made and match drilled

Next was to match drill the F-601 J angles. This material is .187 thick and is aligned parallel to one stiffener and 3/32 inch from the lower stiffener. I clamped it in position and match drilled from the far side using the firewall holes as the guide.

F-601 J angles match drilled

Then I match drilled the rest of the holes in the firewall parts. This thing is ready to disassemble, deburr, and start countersinking/dimpling for assembly.

Firewall parts match drilled

Categories: Firewall, Fuselage

Started the Firewall – 2.5 hrs

April 23, 2011 Leave a comment

Saturday Apr 23, 2011

This marks the official start of the fuselage build. I spent at least a half hour locating parts and raw materials for parts called out on drawing 19. I’m still not sure about the right raw stock to use for a couple of parts. I may post a question on the Vans Air Force forum or call Vans on Monday. The first construction step is to make the left and right F-601J angles from 2 x 2.5 x .187 extruded aluminum angle. This is pretty straightforward, cutting to length, cutting chamfers, and smoothing all edges. Here are the finished angles.

F-601J Angles

Then I started laying out parts on the firewall bulkhead per drawing 19. This is not everything, but most of the firewall parts. I’m starting to think a lot about if and how I will paint the interior of the cockpit. This side of the firewall in inboard so if I want to change primer system for the interior this is the time to do it. More research to come.

Firewall parts cleco'd

Categories: Firewall, Fuselage

Left Wing Pitot Line Routing- 4.5 hrs

April 23, 2011 Leave a comment

Saturday Apr 23, 2011

Instead of starting on the fuselage this morning I decided to work on the pitot tube plumbing routing in the left wing. The details of this work are left up to the builder because I am using a non-standard pitot tube. First step was to install the fittings onto the pitot and AOA tubes from the SafeAir1 kit. For this I used my Parker Rolo-Flair tool to good effect.

Tube fittings installed

Then I installed platenuts onto a bracket I made to support the fittings from the nearest wing rib. But before that I primed the bracket with rattle can NAPA 7220 primer.

Pitot tube plumbing bracket

I also made another bracket to organize the pitot and AOA tube and pas them underneath the aileron bellcrank. You’ll see how that works in a minute.

Pitot tube line bracket

Then I located a place to mount the heated pitot tube electronics module on a rib and match drilled holes. Then I installed nutplates on the back side of the rib as seen here.

Nutplates for heater module mounting

Then I riveted the plumbing bracket to the rib with pop rivets and installed the fittings for the plastic pitot lines. I’m using Adel clamps to hold the fittings securely to the bracket.

Rigid line routing to fittings

Here is how it looks with the pitot lines running through the organizer underneath the bellcrank. The clearance looks good and you can see that I primed the bracket before installing it under two of the bell crank bolts.

Plastic lines neatly routed under the bell crank

Here is the electronics module mounted where I can get to it through the access cover. There are two bundles of wires exiting from this module. One goes to the pitot tube an the other will be routed through the plastic conduit to the wing root. The wires from the pitot tube are a little shorter than I would prefer. They just reach to the rib where there are three spade connectors and a two pin mini molex connector.

Heater module mounted

I wanted a way to tie down the wires and connectors so they won’t flop around so I made another little bracket to wrap a zip tie around as you can see here. Although not ideal, I should be able to wrap a zip tie around this from the access port in the wing. Now the only part of this job left is the routing of the wires from the electronics module to the wing root.

Electrical wiring bracket

Categories: Pitot Tube Mounting, Wings

Back from Vacation

April 22, 2011 Leave a comment

Friday Apr 22, 2011

Well I’m back from vacation – at least physically. I can’t say my body has caught up with the Pacific Daylight time zone yet though. Denise and I spent about 11 days in Israel seeing the country and visiting my daughter who is studying abroad there. She is coming back in two weeks but she had time to be our tour guide.

Here we are at the Mount of Olives looking back over the Old City of Jerusalem and the Temple Mount.

Far from the RV7A Factory

We arrived back home around noon today and I was so jet lagged that I couldn’t really build anything I would want to fly in so I just finished the inventory of the fuselage parts. Everything was there except one J-channel. My kit has five instead of the six listed on the bill of materials. I’ll call Vans about that on Monday.

Categories: General