Started Cowling

Continuing to catch up on the posts so I'll just let the pics go through everything.

As you can see the cowlings don't line up very well from the factory. The whole section is really just about getting them cut to size and having everything match up in the end. The instructions seemed to do things backwards then the way I thought you'd do them. So after thinking things through I decided to just approach cutting and fitting these like a wood working project. After I got in that mindset things went really well.

One thing I should note is that I made the cut out in the lower cowling for the front landing gear leg much wider than what the plans call for. The plans dimension is so tight I couldn't even install the cowling over the landing gear. So I increased it by (I think) about 0.75".

So I couldn't use the table saw to make a nice straight cut like I would for building furniture, so I broke out the laser level to mark a straight line from the ridges of the inner circle to the outboard edges of the cowling openings. I used the ridges as a guide to know when I had the cowling level. I then trimmed down the outboard inlets flush to the lines that were made from the laser level leaving the sides sticking up to be cut later.

With the front edge cut the two halves of the cowl could rest against each other and I was able to tape them up into place. First I taped up the bottom cowl and got it into place. I used some spacers up front against the spinner and then just duct taped the cowling to the engine to suspend it in place. The aft part of the cowling rested against fuselage skin.I then used an edge finder, just like I did with the doors, to mark the edge of the fuselage onto the cowling. I then cut the cowling along the line and re-installed it with a few clecoes into the hinge to hold it in place. I re-taped in place in front around the spinner with spacer blocks. I then repeated the process for the upper cowling and after I cut it I placed it in position. The pic below shows how well the fuselage and upper cowl lined up. I wound up increasing the clearance between the fuselage and cowlings all the way around to about 0.10" or so.

With the cowlings clecoed in place along their hinges the upper cowl side overlapped the lower cowl. I made a straight line mark using a chalk line positioned at the leading edge joint and the aft edge point. You can see how the upper cowling was not perfectly straight.

The entire time I had a chunk of scrap wood that was the right in the middle of the clearance tolerances listed in the instructions. I had a large piece spanning the upper joint and several tapped in position (as shown in the picture) around the lower opening. You can also see how the cowling sits just below spinner. I've heard you want to have this because the engine "settles" in place and will drop a bit.

I cut the upper cowling and then used a large flat sanding block to really flatten the cut out. I then clecoed the cowling back on and used the upper cowling to mark the cut line for the lower cowling. 

With the two halves cut and sanded I had zero clearance between the two halves. So I had to remove the upper half a few times and sand it down just to create some kind of gap between the two. I then installed the horizontal hinges per the plans except a bit shorter to accommodate the Aerosport Pin Covers.

Everything lines up pretty well. The only thing I need to do now is some body work around the openings.

Spinner and Temporary Prop Install

Ok. I'm so far behind in my posts I'm just gonna use the pics to run through what I did and wait until later to post times and such.

I built the spinner mount plates and then Alodined and painted them. Pretty easy step and I thought they looked really nice.

I printed off the cut templates that Hartzell made for this prop and glued them to the spinner to mark my cut lines. The only trick is that the two templates need to be 180 degrees off from each other. So I made a string the length of the perimeter and then measured the half way point on the string. Then wrapped the string around the perimeter again and the half way mark is exactly 180 degrees off the other mark. Simple.

Everything lines up really well. No gotchas in this section. The spinner kind of centers itself on the spinner plates.

After I got the spinner at least clecoed in place I wanted to start on the cowling. I knew that after the cowling fitting would be done I'd want to take the prop back off for the engine work anyway. So I figured I'd just finish the spinner then and install the prop now. 

The prop goes on pretty quickly. I did the whole thing solo. So it is possible to install by yourself. The only PITA is getting the bolts tightened up when they are trapped in their small space. So you can't screw in one bolt very far before you have to tighten all the others. So you just make baby steps all the way around until they are all tight.

To keep this post on topic I skipped writing about the cowling work and jumped to the part where I have already taken the prop back off for the engine work and finished the spinner. I'll write about the cowling soon. 

Once I had the spinner plates final drilled and all the nutplates installed I torqued and safety wired the mounting bolts. 

This is the best shot I have but I wanted to show that instead of making additional close out plates for behind the propellor I just used the pieces I cut out of the spinner in the beginning. So be careful when cutting out the propellor clearance holes in the spinner and you can reuse them for the close outs later.