Baffle Seals, Oshkosh, Cowl and Spinner

Hours 59
Total Hours 1144

My two weeks off this time consisted of two days work on plane, then 5 days Oskosh Air Venture trip, two days work on plane, 4 days family lake trip, then two days work on plane. I have been getting up to work on the plane at 3:00 am then quitting at noon because August in Texas makes working in the hanger without an air conditioner very uncomfortable in the afternoon.  Before we left for Oshkosh, I worked on my oil cooler mounting and got everything finished except for mounting because I need to order the right length bolts. I will also build a brace from stainless  tubing as the baffles are bad about cracking without additional support.

The baffles are mostly complete now.

Next I started cutting paper patterns for the baffle seals. The baffle seal material Vans give you in the kit is just enough to do the job so I used the patterns. The plans call for 2" of material above the baffle and 1" below the baffle. This is a selfie  pic as I am not in many of my pictures.

More patterns.

I'm not sure how the baffles seal in the front and around the crankshaft so I left plenty of materiel in these areas. I plan to solve this mystery looking at planes at Oshkosh.

This shows the gap between the cowl and the edge of the air intake area of the baffles. A gap is necessary because the engine will be shaking while the cowl will be stationary. 

The plans show a conical aluminum piece rounding out this corner but if I put one in, it will black part of my air filter. I'll contemplate this for a while along with sealing all this area off.

Trip to Oshkosh and Airventure 2014

 I had planned the trip to Oshkosh in February and had it all set up and was excited as hell about it. I was finally going to see multiple RV7's and get to talk to some other builders. We got up at 4 am and made it to the airport for a 7 am departure and just before the plane pulled out of the gate the pilot announced that they had found a hydraulic leak on the plane. We de-boarded and after waiting till 3:00 PM, SWA cancelled the flight altogether! It was a dagger thru my heart! Our only choice was to book the same flight the next day. 
I was really upset because three days at Airventure is not enough, now we were cut down to two. Nancy and I finally arrived at Airventure 2014 on a Friday evening. The time it took us to travel to Oshkosh by commercial airlines wound up being about 34 hrs! I believe I can beat this by at least 24 hrs flying my RV7 next year!........Well all that aside, we had a wonderful time! I still got to see many RV6's and 7's and visited with several pilot/builders and made lots of new friends. The folks we rented the room from gave us a great taste of hospitality Wisconsin style and they were wonderful! We looked at a lot of paint jobs and I stuck my nose in several horizontal induction RV's to look at the baffle seals. I also took a lot of pictures of these. The one thing that really made an impression on me was, none of the planes were perfect! Most had very small flaws like cracked paint over rivets or a scratch here or there but it made me relax a little about some of my little cosmetic flaws. The EAA people that put this show on were really friendly. They did everything possible to help us get all we could out of our short time. My phone app said we walked over 8 miles on Saturday! It was everything I expected X 2. My first trip to Airventure was a huge success. My advice to anyone that has not been is go before you start building, do not wait till you are almost finished as I did. Well, I do have a good "lay of the land" now, and I feel comfortable flying in next year!

My bride of 33 years standing beside another beautiful creation at Airventure! I am so lucky to have a girl that supports me and my crazy adventures. She can buck rivets too! I think I have her talked into camping on the ground in a tent for several days next year after flying 1,100 miles in our home made airplane!

Great trip but I couldn't wait to get back at home and dive in to the baffle seals! I had previously decided to paint the baffles but after looking at all the planes at Airventure, not one of them had the cowl off so I may just paint the intake ramps as that is all that will show.Vans demo RV7 had unpainted scratched up intake ramps so I'm not going to spend the time.

I needed to seal the ends on the fiberglass dams on the cowl so the seals would seal well against them. I didnt take a picture but I glassed over this foam block that I carved and shaped from some stereo-foam I had laying around.

  One thing I noticed at Airventure was that all the horizontal induction RV's did not have the traditional Vans "Snout". I bought this project and never gave it much thought that it came with a vertical intake cowl with the snout. Vans sells a horizontal intake cowl that is smooth. The snout on a horizontal cowl really has no purpose and even though I had grown to like the looks of the snout, it bothered me that it would always be there, possibly causing additional drag (never been proved). I would also need to plug it as it being open would prevent the lower half of the cowl from being lower pressure than the upper half of the cowl. This would hamper the engine cooling ability. When I started this project, I decided what I wanted was a very clean look. Thats why I installed hinges to mount the cowl. I also plan to install hinges to mount the wing tips. I fought with myself for several days but finally decided to do some surgery on the cowl and amputate the snout! This is what everyone warns everyone about with building an airplane! Modification cost time. This will cost me a lot of time for sure............

I studied the snout and decided to cut it here. Notice the strip in the middle that the previous builder had cut for a nose gear?

I cut the snout out.

Then I cut the upper part of of the snout off the bottom piece and studied on how I could use the old piece to keep me from using up all my fiberglass cloth and building a mold.

Here is what I need to clear with the bump.

I would up forming a makeshift mold out of the old piece and packaging tape.  

I then glassed the inside with two layers of heavy 2" fiberglass cloth tape.

When that set up, I mixed micro balloons with  just a dab of flox and built up around the bottom to smooth it out.

Unfortunately, the heat muffler still needed more clearance. I cut out the hole to add a "blister" 

I glassed in the blister. Now the job at hand is smoothing everything out and making both sides match. I am doing this with batches of micro with just enough flox mixed in it to hold it in place. Add a little here, let it set up, and sand it while its green, then do it all over again. If I had to do this over, I would have made a mold out of something the first time so that the muffler would clear. This modification is costing time and materials but the last thing I need is the cowl to get burned spots ruining my paint job later down the line!

While working on the cowl reconstruction, I started another time consuming project! I want a screwless spinner to contribute to my "clean look"! Here is a look at a picture of one. I found it on the internet. It is so clean and slick without any screws showing! I have been studying this mod for a long time and I want it! All it will cost is TIME! I will keep a close watch on it to make sure it is secure after each flight but several builders have been mounting this way successfully.
 


First I needed to sand the proper prop openings in the spinner and the fillets that go on the back of the prop. To do that, I needed to see how much the constant speed prop adjusted when oil pressure hit it. I had read about hooking up an airline to the prop hub. I took a 1 1/2" pvc fitting and it fit perfect inside the prop hub. Hooked up to a regulator set at 35 psi, I could hold the greased fitting in the hub and watch the blades adjust all the way out. I trimmed the filet to give the prop plenty of opening. This is my PVC fitting.

I wrapped the rear spinner bulkhead with packaging tape and the waxed it several times. I cleckoed the spinner to the bulkhead and laid up a flox/epoxy filet in the corner. You can see the fillet just inside the spinner. This will help the fiberglass make the curve and give the flange more strength.  

 After the fillet set up I laid up 6 layers of 8" bid cloth then topped it of with a layer of the heavy 2" fiberglass cloth tape and let it cure.

I was a little worried about getting the flange to pop loose of the bulkhead but after a little prying with a screwdriver, it came apart.

Then I trimmed up the flange and installed #8 nut plates. 

This made a very strong flange. Now the screws will attach the bulkhead from the rear of the bulkhead and not be visible.  I will proseal the front flange to the spinner with mold release on the spinner to create a tight fit on the front and prevent any wobble. This turned out nice and I'm pleased with the new skills I have acquired working with fiberglass!

 Thats all I accomplished in this go around and its back to work tomorrow for a 3 week hitch. I have a lot more shaping to do on the cowl and still some baffle seal work to do. It seams I have 20 different projects going at once with the plane and I cant seem to finish any of them! Hopefully I can make some real progress in September. I would like to be painting before the first of next year, but whatever it takes, it takes.