Wrap Up Work 7
1/14/2007 8 hours
Seems like forever since we worked on the plane. I guess it's a long time because since it's been airworthy, I've been flying it whenever I can. Today, the weather is crap so I figured it would be a good day to do the gear leg fairings. An incentive for this is MORE SPEED! I wonder how much?
Airspeed has been around 135-140kts on about 60%-65% power so far around about 2500ft. It'll be interesting to see how much difference they actually make.
Clayton came by to help too, and we had a lot of fun today working on these.
I went out and bought an engine hoist to lift the plane up. This has to be done so that the gear leg fairings are aligned with the airflow in the flight attitude. I also bought some "Great Stuff" expanding foam. We're filling these legs up with it from the get go, not waiting until something breaks. Some people may consider this foam as a bit bodgy, but in my opinion it's not. There are many places on your car where something very similar is used to seal up the cavities in the body structure. Usually it's attached to a special plastic bulkhead with the stuff around the outside of the plastic. When the car goes into the paint oven the foam expands filling the gaps.
Clayton assembled the hoist while I cut the templates from a copy of the drawing and made the fairings. These are pretty easy to do, but a little time consuming. It took us most of today to do.
Here, the plane is raised so the wheels are a smidgin' off the ground (about an 1/8th inch, if that.) We did a test fit of the fairings, and trimmed where necessary. We didn't trim the back edge of the fairing to the template, because I wanted it to fit into the Farings Etc, intersection fairings, so we fitted the intersections and established our own rear trim line.
Here's Clayton in the obligatory 'Coneheads' shot.
We match drilled the rear hinges and countersunk the holes for rivets. We roughed up the fibreglass and the hinges with 40 grit sandpaper and bonded and riveted the hinges in place.
Once that was done, it was time to get it on the plane! Fast! It was quite cold today, so it helped with the cure time for the epoxy. We still chose the fast stuff though. The slow stuff takes forever!
We put a flox mix all the way down the gearlegs where the fairing touches the gearleg, and a flox mix along the trailing edges of the fairings. Next we slid the fairing over the gearleg, positioned it roughly and slid the hinge pin in to close up the rear edge. Once it was in about the right position, we used the upper intersection fairing as a guide for the correct angle, and then checked it with plumb bobs and a string to the back of the plane. I put a laser line on the floor parallel to the centreline to help us get it all right. The intersection fairings are pretty close. You have to make sure the fairing isn't twisted as it goes down to the bottom though too.
Once it was all secured, we squirted in the "Great Stuff". It's pretty cool stuff really, as it fills up all the gaps really nicely. I don't think these fairings are going anywhere! The fact that I had previously fibreglassed the brake hoses in also will help in this regard as the peel ply had left a great surface for the new flox mix to adhere too.
Well tomorrow I'll try to get back here and secure the upper intersection fairings. I'll probably have to trim off some of the expanding foam, but it shouldn't be a big deal.
3/31/2007 7 hours
As well as the GX-60 installation, I decided it was time to get the oil door started. I'm so sick of pulling the top cowling for every preflight now to check the oil and unplug the cylinder heater. I've seen lots of people out there use the Van's fibreglass door, and they end up reinforcing the hell out of it coz it's just too flimsy, it just bulges when you take flight. Not pretty. I decided to 'roll my own' (pun intended). It's not even compound curvature, so if you are fortunate enough to have a set of rollers, it's very easy to make a door out of 0.063" sheet that matches the cowling perfectly. Here I've fitted the latch and hinges too. I stole the hinge idea from Dan C, thanks Dan!
4/1/2007 9 hours
On today's agenda are the wheelpants and finishing the oil door installation. First up was to slap on some carbon fibre reinforcement for where the wheelpants get riveted to the brackets. That way, it can be setting up while I crack on with other things.
Back to the oil filler door... I cut the opening and got the hinges drilled to the cowling in the correct position. I also added a piece of 0.030" aluminium strip to the latch contact area for added strength. Something I did with the hinges was make them contact the edge of the door opening slightly. The hinges themselves don't actually swing through a true arc, so as the door opens, they're free, then at about half open, they rub against the edge of the opening. Once the door is about three quarters open, they free up again, so the door will stay open when I put it open. It took a few iterations of fitting and filing to make it work just right. I'm not sure if eventually it'll wear the fibreglass away and just fall closed one day. We'll see.
Since Van's filler hole is square, and my door isn't, I waxed up the door and slapped some filler on there. I think this was the first dollop.
With a little patience, eventually it looks like this. Absolutely lovely jubbly! The best fitting oil door East of Oshkosh AND West of the Netherlands! Aart, Harm, Pim and René's oil door!
I hate fibreglass so much, I make myself look like an idiot trying to stop the scratchies!
Time to move back to the wheel pants. I didn't really take many photos along the way here, but I basically cleco'd the two halves together, and trimmed out the hole in the bottom for the tyre until it just fit. Once the final position of the pant is established, I'll trim out the tyre hole more to provide the required clearance.
I raised the back of the plane, and hoisted the front up so the wheels were just touching the ground, and made sure the plane was level in a flight attitude. Then I laid two laser lines on the floor, one down the aircraft centreline and one just inboard of the wheel (in this case the left one). You can't see the lines on the ground coz of the camera flash. I had to dim the lights some to do this too.
I taped a 1 inch block to the top of the wheel and went forth with positioning the wheelpant. it took a while to get to this point, but I finally got it cleco'd into place. In hindsight, I would've drilled the holes first, then reinforced it with carbon. It's tough to shine a light through and see where to drill when there's carbon in there. Be warned! Despite that, I managed OK and got a pretty nice result. Now all I have to do is the other side. The pant is prepped ready to go, I just have to hoist the plane up again and go through all the set up stuff. I didn't want to leave the plane hoisted overnight for obvious reasons. The hoist might drop slowly since it's hydralic, and who know's what would happen then.
So tomorrow I'll crack on with the other side, and hopefully get them all riveted to the brackets. Next week we have a trip to Chicago planned, so it would be nice to have made some headway into these by then. A little extra speed on a cross country won't hurt either! Demon!
This evening I continued with the wheelpants. I got the right hand one aligned and cleco'd. Next task was trimming the wheel hole and generally cleaning them up ready to assemble.
I did take pics tonight, but left the card in my camera. I wasn't expecting to be updating the site this evening, but I need to come down from my late night soccer indoor soccer game.
I cleaned up the wheel openings on both wheelpants and then countersunk the holes for screws. Next I put #6 the nutplates on the rear half of the left pant, and riveted the outer bracket to it and put some epoxy and flox around the whole lot to give it some extra strength. I do like the flox stuff, it works pretty well.
I put drilled the inner brackets for nutplates too. Man that was a chore. We're using stainless brackets, and they're pretty darned tough. Then I riveted the nutplates on. Right now, the left wheelpant is about ready to be put on properly. Sweet! Now I need to catch up with the right side and get them on and fly the plane to see how much difference they make.