Baffle work and more cowling

I had some family help working on the various baffle parts. Dad is working on some edge finishing!

My brother Paul was in town for a visit and fired up to work on the RV-7.

Flange drilled to the baffle and hole cutout for the oil cooler air supply:

After a good bit of sanding on the ex-bulge spot I applied another thin layer of filler and also worked on filling pinholes on the lower cowl.

Making progress on the aft portion of the baffles:

  

This is after sanding the first layer of microlight filler. It came out a little low so I added another layer.

I used the West low density filler to build up the area around the spinner. It's definitely stronger but harder to sand. 

A little windscreen work and battle of the bulge

I removed all the clips and spacers from the windscreen. I'm very happy with the results.

The next step will be doing some sanding on the outside Sikaflex and then applying another layer to fill gaps left by the spacers and clips. I will also try to get a nice cosmetic fillet on the inside of the roll bar.

I was happy to remove the ill conceived bulge from the lower cowl!

I used some very thin aluminum as a form for the new fiberglass:

Here is the form ready for fiberglass:

I went with 4 layers of cloth to give more allowance for sanding:

The initial repair went well. Although a fair amount of filling and sanding is still to come.

Initial Sikaflex windscreen install

I was able to get the first phase of the windscreen install done today. I'm happy with the results so far. I think all of the prep work will pay off.

I went ahead and installed the defog fans. (I'm really looking forward to "permanently" installing the instrument panel and all the avionics!)

 

Windscreen taping in progress:

 Fuselage taping done:

Windscreen primed with Sika 209D (used the "Aktivator 205" first):

Fuselage primed:

First application of Sikaflex 295UV after some smoothing. I taped some weights to the windscreen to help close a small gap in the front.

I'm going to let the Sikaflex cure for a few days then I will remove the clips and spacers. I will clean everything up and apply a more Sikaflex and try to get a nice finish on the inside of the canopy. I will also be adding some weatherstrip to the inside and the outside will be covered by a fiberglass layup.

Inverted oil system hose and windscreen

I was not happy the appearance of the bulge I installed in the cowling to allow room for the routing of my oil return hose from the half Raven inverted oil system. I was either looking at major rework on the bulge or hose reroute. I found that a 180 degree fitting would allow a different hose route and not require any cowling change. I watched the EAA video on making your own hoses and ordered parts from Summit Racing.

Here is the key 180 fitting and the 10AN braided hose with the new route:

The hose is just for draining oil back to the sump. The Raven sump fitting is also protected by a standpipe in case of hose failure. 

These tools made the process easy: no mar aluminum adjustable AN wrench and vice jaws, also the ice pick and modified pliers make adel clamps very easy to install.

Glareshield paint turned out nice:

After priming glareshield:

Windscreen ready for install. 

I will use some weight on the center of the windscreen and the temporary clips on the sides for the initial Sikaflex application.

Getting closer:

A lot of on and off and iterative sanding with my small belt sander.

Initial fitting:

I also did some reinforcements on the wheel pants:

Intersection fairings (wheel pant to gear leg) and engine heat power plug:

Power plug with backing plate for Reiff engine sump heaters. Plug is standard computer power supply plug and can be easily replaced. Backing plate will get attached with g-flex epoxy.

Plug location under cowl is easy to access and low profile:

Left wheel pant / intersection fairing combo after being cut off / removed from the landing gear:

Right wheel pant after fiberglass layup. (I'm happy with the expanding foam but it was definitely a learning experience. The foam is extremely easy to shape but I think the main trick is to get consistent coverage when the foam is expanding.)

Some of the foam turned out a little lumpy but it still seems to beat the other methods. Next time I would consider using a more dense foam such as 4lb.

I used a 3 layers of fiberglass for the top of the intersection fairing. These were wetted out in a stack. I used tape for the underside but I did cut off all the seams.

Right fairing after shaping:

Next time I would spend a little more time building a more accurate "dam" for the foam. I would also plan on pouring the foam in two mixes to cover the top of the gear leg better. This was about 320 grams of foam.

Checking the fiberglass dry on the left side. My fiberglass skills still need work. The glass looked good on the top but when applied it did not want to turn the corner and stick to the underside. 

The foam carves down very fast with a hacksaw blade.

The endless cowling

The initial bumpout to clear the inverted oil system hose:

Inside view of the bumpout before finishing:

Peel ply over fiberglass lay up:

Initial fiberglass layup:

Ready for fiberglass:

Did a little more sanding on the cowl flap opening and checked the fit:

Top cowling with a rough layer of filler ... almost all will get sanded off! #carpaltunnel