Baffled

Things are moving quickly from one task to another now and it's getting really difficult to keep track of what I'm working on, when, and for how long. The baffles are the last big item to build. So it deserves its own post. 

I had a a soon to be RV builder stop by the shop a few Saturdays ago. He asked to hang around for a while and rivet on some practice pieces while I supervised and advised. He said he learned a lot, so I guess it went well.

The baffles aren't bad. It brings you back to the "good-ol-days" of just smashing rivets and bending tin. 

The times listed below are a mix of many different things including: baffles, oil cooler install, air intake in cowling work, etc.

Time and Dates
Sat 6   -2.5 hrs 
Sun 7  -5.25 hrs-
Mon 8  -1.25 hrs
Tues 9  -1.25 hrs
Fri 12  -7.0 hrs
Sat 13  -5.5 hrs
Sun 14  -5.0 hrs

Cool shot from the loft of the shop.

After the aft baffle parts are riveted together I installed the untrimmed parts for a test fit.

Getting the aft baffles on is a PITA I wound up scratching up the valve covers. I taped them up to protect them from any more scratches.

On the LH air ramp I didn't follow the directions for trimming the part. I instead trimmed it as the marked in the picture. If you follow the directions you could have some edge distance issues with rivets in the next couple steps of the instructions.

RH air ramp bent up and clecoed in place.

LH air ramp bent up and clecoed in place.

This shows how much extra material you're dealing with on the air ramps. Things will get trimmed, A LOT, later.

I moved the scat tube intake farther back than the plans call for to prevent the lip of the cowling interfering.

This is the LH air ramp. You can see how my trim worked out. Nice edge distance on the fasteners.

I had to open the hole to clear the prop governor.

Here are all the components installed with the lower cowling in place. (Note the dancing in the background....I'm pretty sure she was entertaining Ayla :)

Next step was making the conical ramp corner gussets. I made a few templates from paper to get the idea of what kind of shape I would need. Then to the bend I gently rolled the aluminum with my hands on a piece of scrap tubing. It worked pretty well.

RH corner gusset cut and clecoed in place.

LH gusset cut and clecoed in place. I later had to remake this part. The bend I made on outboard baffle wound up pushing the ramp up 3/8 of an inch higher than the cowling lip. So I had to drill out this gusset shown and remake another to allow the ramp to sit lower.

RH gusset riveted in place. I'm really happy with the way this turned out.

I then evenly space the cowling up 3.5" to make marks for my initial cut.

I made a mark 3.75" all the way around the baffling - 0.25" lower than the cowling top - for my initial cut. I cut to that line then placed paperclips around the perimeter of the baffle. Placing the cowling back on pushed the paperclips down. Then I could go back and measure 0.5" from the top of each paperclip and this would give the points I need to have 0.5" clearance all the way around the perimeter of the baffle.

Made the cut and then removed the baffles and prepped for paint. A pile of twisted angled parts.

Selling Some Stuff

I am selling all of my Dynon equipment. See post on VAF Classifieds if you're interested.

Filtered Air Box Alt Air Door Redo

A few posts ago I had a picture of my FAB with fiberglass layed out to make an alternate air door. Well, I had a real hard time getting the piece of aluminum I was using as a spacer back out of the glass I layed up. While I was pulling and cussing and pulling more I realized that the glass wasn't really adhered to the box very well. And eventually it all just popped right off. SO...back to the drawing board for the alternate air door. I should have trusted my instincts and made if from aluminum in the first place.

Mon (Labor Day) Sept 2 -2.75hrs- Worked on Filter Air Box and final install of throttle body

Here are the pieces that make up the alternate air door. Bottom plate, two middle spacer strips that are bit thicker than the sliding plate, two upper retaining strips, and one strip across the back to act as a stop.

The four center holes fall inside of the filter so those will be riveted in place with button heads to the FAB. The outer rivets are countersunk since they fall under the filter.

Here is a pic of the door installed. The four center holes on each side of the strips attach to the FAB and the outer ones along the forward and aft edge are just countersunk as you saw in the above picture. Also you can see that instead of fiberglassing a tube into the box bottom for a drain tube, I went a different route. I used one of Vans unused static port compression fittings and cut the threaded part down to the thickness of the FAB. Then installed it into the box and globbed up some flox epoxy and glued it in place. With the compression fitting installed I can swap out the tube if I need to. It also seemed like an improvement over the original idea and was easier to install.

I made a little hat channel to attach the cable hardware to.

This is a picture looking up at the the throttle body. The throttle body was installed per Lycoming Service Instruction No. 1484C. Then the upper FAB plate is bolted on and safety wired.

The FAB clecoed in place.

I currently have the baffle material on the inside of the FAB neck, but after thinking about it I would prefer to have it on the outside. My thoughts were that this would be better for airflow, but if a piece of that tore loose it would really block air intake. So, I'm gonna drill it out and move the material to the outside. Then I can finally finish the cowling transition piece that slides into the FAB opening.

Exhaust is Installed

My In-laws were in town over the weekend and what better way to enjoy Labor Day weekend than installing exhaust on an IO-540 engine. OK...I can think of a lot of things that would have been more fun but it was still a good time hanging out in the shop and tinkering around on the plane. With help from my Father In-law we casually worked on the exhaust from start to finish in just a couple days. The job was pretty easy and it felt great starting and finishing a section in such a short amount of time.

Sat and Sun 30-31 -4.0hrs- Started and finished the exhaust.

Pretty easy section. Followed the plans with no surprises or issues.    ....doesn't the engine looks much cooler with the exhaust on?!

The heat muff is suspended from brackets and rubber linkages. It's easy to figure out once everything starts coming together. It was a lot of help having an extra set of hands for all the Adel clamps and such.

You just follow the numbers for each cylinder and everything starts lining up.

I was concerned about the clearance between the fuselage and the cowling. There are plenty of ways to tweak the position of the exhaust and I'm happy with the clearance I got on both sides. Once everything is installed I was surprised how solid everything is. You can shake the plane by pulling on the heat muff.

Here is the shop lead technician hard at work! (note the tools hanging from her pockets).

She had to inspect my work. It was approved!...whew.