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Archive for the ‘Fiberglass Tips’ Category

Tail Light Adapter Part 1 – 1 Hr

July 29, 2010 Leave a comment

July 29, 2010

My tail light adapter and tank dimple dies arrived from Cleveland Aircraft Tools today. I’ll need the dimple dies when I get to the fuel tanks but for now I can install the tail light adapter on the rudder bottom fairing. Here is the little $17 aluminum part.

I aligned it to the fairing contour by eye (a little awkward) and match drilled the holes in the fairing. The alignment turned out OK in spite of the fact that the fairing is not perfectly symmetrical.

Then I marked the center hole on the fairing and drilled it out using a 1 inch spade bit from my woodworking supplies. That worked surprising well. Then I smoothed out the edges of the fiberglass with my rotary tool and a sanding drum.

Ready to prime the adapter and install it with CS4-4 rivets.

Categories: Fiberglass Tips, Rudder

Installed Horizontal Stabilizer Tips – 1.5 hrs

July 18, 2010 Leave a comment

Sunday July 18, 2010

Today I permanently installed the horizontal stabilizer tips. I match drilled all of the holes to #30, then removed the tips and cleaned out all of the chips. Then I dimpled the holes in the skin using my pneumatic squeezer. Next I countersunk the holes in the fiberglass using a countersink head on a manual drive handle. Then I installed the tips using CS4-4 pop rivets.

The fits between the tips and the skins are quite good. The seams are tight and the leading edges line up nicely. So I am thinking about leaving these alone and not filling the seams with dry micro.  I think I’ll move on to the rubber bottom fairing and that will give me some time to think about it.

Finished Elevator and Rudder Tips – 4 hrs

July 17, 2010 Leave a comment

Saturday July 17, 2010

Big day today. I officially finished the elevator tips, rudder top tip, and vertical stabilizer top tip. The morning started with sanding out the dry micro that I applied last night on the VS tip seam. After shaping and blending it into the skin and the fiberglass there were several low areas where more filler was needed so I mixed another batch and applied that.

It was hot again today so it only took a few hours for it to kick over. Then I sanded it again to get the final clean shape I wanted. Seam gone!

Next I broke out the spray gun and sprayed on a few light coats of UV Smooth Prime, which I had learned about on the forums. It fills pin holes and small defects and sands out really smooth. It also provides UV protection to the fiberglass. I guess that’s important. It drys pretty fast too in light coats so it was only about a half hour before it was ready to sand.

Here is the finished VS tip.

Then I sprayed UV Smooth Prime onto the two elevator tips and the rudder top tip. I’m new to working with fiberglass so I am happy with how well these came out.

Here are the two elevator tips.

Here is the rudder top tip.

And here is how the rudder and VS tips fit together.

Here is a closeup of the gap.

I retrospect I am glad that I have time before my wing kit arrives (week of August 8 according to Vans) to finish the fiberglass on the empennage. Most builders postpone it until after the wings and fuselage are done. But I would rather get this dusty stuff done and out of the way. If the wing kit was already here I am sure I could not resist the temptation to focus on that because there is so much satisfaction in seeing the big pieces come together. But now I know how time consuming the fiberglass work can be if you have a perfectionist approach, which I sorta do. It has take a lot more hours than I ever expected and I learned a lot. Hopefully something I posted here may help someone in addition to documenting my process for the FAA.

Ah, but I get ahead of myself. Next: Filling the seams on the horizontal stabilizer tips and installing the rudder bottom tip.

Rivet On the VS Tip – 2 hrs

July 16, 2010 Leave a comment

Friday July 16, 2010

Today after work I decided it was time to permanently attach the vertical stabilizer fiberglass tip. I had already match drilled and dimpled the skin so it was just a matter of riveting it on with CS4-4 pop rivets. I want to make it as clean as possible so I mixed up a small batch of epoxy and applied a strip of deck cloth over the seam. I used a layer of peel ply over that to minimize the sanding later.

I was hot today ( in the 90s) so the epoxy kicked over really fast. It was hard and sandable in two and a half hours. So I sanded the small amount of glossy epoxy that wasn’t under peel ply and then slathered on a layer of dry micro across the seam and over the end row of rivets on the skin.

Tomorrow I’ll sand this out and see if I can get a smooth transition from the aluminum skin to the fiberglass.

Apply Primer to Rudder Tips – 1.0 hr

July 11, 2010 Leave a comment

Sunday, July 11, 2010

I pulled out the spray gun yesterday and applied a coat of West Systems primer to the rudder and vertical stabilizer tips today so I could see any remaining imperfections in the finish and shape. Today after it was well dried I took these two photos.

The finish and shape are just about the best I could hope for. There are just a couple of very minor surface defects that can be fixed easily and a few pin holes. I’ll do a little bit of filling and then apply a coat if UV Smooth Prime to kill the pin holes. Then I’ll rivet on the VS tip and fill the seam between the fiberglass and the skin.Then these babies will be done until the ultimate paint job is applied.

Categories: Fiberglass Tips

Finish Tuning Rudder Tips – 2.0 hrs

July 8, 2010 Leave a comment

Thursday July 8, 2010

Last time I added filler to the rudder and VS tips to fine tune the shape at the top edge. Tonight I sanded out the filler on both parts to get to the final shape. I am pretty satisfied with the results. There is one tiny dimple that I will fill next time I mix dry micro. The edges are now almost flush with the VS tip very slightly taller than the rudder tip at the intersection. That makes sense to me because the VS tip leads in the air stream.

Here is the shape looking straight down from the top along the hinge axis. That gap is about 0.100 inch.

Here is the rudder tip leading edge with the rudder rotated for a left yaw.

This weekend I plan to spray on a coat of West Systems primer to check for any minor flaws that are hard to see right now. If all is good then I will permanently rivet the VS tip to the VS and begin the process of filling and sanding the gap between the two pieces.

Categories: Fiberglass Tips

Fine Tuning Rudder Tips Part 2 – 1.0 hr

July 6, 2010 Leave a comment

Tuesday July 6, 2010

Part 2 of this task starts with sanding the tip of the vertical stabilizer to shape the dry micro closer to the desired match with the rudder. Using 80 grit to rough sand it first then 220 grit to smooth it out this process took about 15 minutes. Here is the result. Not perfect but closer to the desired profile.

Next I decided to decrease the radius on the top trailing edge of the VS tip. I have found that making a tape dam to contain the dry micro is helpful so that is what I did.

The radius on the leading edge of the rudder tip seemed kinda large also so I made a dam there and added some filler to allow me to reduce the edge radius when I sand it out. So now these need to cure up and I will sand them tomorrow.

Categories: Fiberglass Tips

Fine Tuning the VS Tip Profile – 1.5 hrs

July 5, 2010 Leave a comment

Monday July 5, 2010

Back to work on the kit today. I wanted to fine tune the shape of the transition from the vertical stabilizer tip to the rudder tip. Here you can see that the rudder tip is a little bit taller than the vertical stabilizer tip. It may not make any difference at all to the performance of the airplane but I would prefer a more optimum transition. Since I am waiting on my wing kit to arrive I figure why not. To make this more aerodynamic I plan to build up the VS tip a little bit with dry micro to match the rudder tip. This may take several iterations to get it right.

So the first step was to sand the gel coat off of the tip and mix some dry micro for build up. I really only need about .090 inch so I laid on a smooth coat of thick filler along the edge and around the trailing edge as you see here. This has to dry before I can start shaping it into a smooth blended airfoil that will match the rudder tip profile. We will see how it looks after I sand it.

Categories: Fiberglass Tips

Left HS and Elevator Tips – 1.5 hrs

June 17, 2010 Leave a comment

Thursday June 17, 2010

After further sanding of the left elevator tip on Wednesday night I was not happy with the shape of the leading edge. It as not square to the inboard edge and the radii were too large. So I wrapped blue tape around the edge to form a dam and poured on a layer of dry micro filler. Here is how it looked.

Tonight I removed the tape and sanded the leading edge. First I sanded it flush and square to the inboard edge. Then I put a slight convex curve on the surface with about an 8.5 inch radius. Here is how that looked. The edges are just slightly rounded here. I’ll round those a bit more later after I am fully satisfied with the general shape. If you look close you can see what appears to be irregularities in the surface. That is actually just color variations in the dry micro layers, the shade of which varies depending on how thick it is mixed. The surface is actually very smooth. You can’t feel those lines at all. There are a few pin holes but I’ll probably deal with those with a coat of UV Smooth Prime or two.

Here is the overall view of the left elevator tip filled and sanded.

I mounted it to the horizontal stabilizer to check the fit with its mating tip. This tip was sanded flat on the trailing edge surface so I removed it and sanded in a matching radius like I did on the right side. Here is the gap between the two parts installed. I will next trim the upper skin just slightly where it overhangs the white fiberglass tip near the dogleg corner.

Categories: Fiberglass Tips

Fill and Sand, Fill and Sand – 1.5 hrs

June 15, 2010 Leave a comment

Tuesday June 15, 2010

Step 1 today was to sand out the right horizontal stabilizer tip trailing edge again. The surface is slightly concave with about an 8.5 inch radius so the surface matches the profile of the elevator leading edge nicely. This one is just about done. There is one tiny surface dimple that I will fill next chance I get and then I will put on a coat of UV smooth prime for the final surface finish in this phase. Painting is a long way off. Look closely at this picture and you might see the dimple.

Then I did some major rough sanding on the left elevator for the first stage of dry micro filler. The peel ply layer helped reduce the waviness of the filler surface and so reduced the amount of sanding considerably. I am satisfied with this for a first cut on this side. The other side only got about half as much filler as it needed because I didn’t mix enough yesterday so it will need another rough layer.

There are some obvious voids in the first layer of dry micro but the area is relatively small. These will be filled in the second layer.

Here is the other side which was only partially coated in the first try.

So I mixed up another batch of dry micro after sanding and cleaning the parts with a clean damp rag. I applied a generous layer on side two and again applied peel ply over that to smooth out the surface and I filled the voids on the other side. More sanding tomorrow.

Categories: Fiberglass Tips