Cozy

Chapter 25 - Finishing - Final prime and Gloss

The finishing process spread itself over more than a year, so it's only right that the file should spread too.

Stucco

At the same time as finishing the bottom of the plane I was also busy remodelling the porch on the house. Some days I'd do an hour of microing, an hour of stucco work, then an hour of sanding. Stucco is easier. You don't have to sand it. Hmmm. I wonder... how would fellow builders react to my plane at a fly in if I showed up with a stucco finish? It would look fine from 10,000 feet!

Getting ready to paint

Finally, in May '01 I got to the point where I was ready to paint stuff. I'd plumbed air from bill's workshop down to my patio months before, but now I decided I needed an additional storage tank to make sure I didnt run out of pressure on a big paint job. We'd recently had to get a new water tank because the bladder inside the old one kept leaking. The old tank was still lying where I'd dumped it. Hmmmm. A few PVC fittings (I have plent lying around) and this old tank could hold all the air I needed. It took 20 minutes from spotting the old tank to firing up the compressor and testing it for leaks. It spat out quite a bit of water, then settled down and held 100 psi without a problem. I bought a couple of rolls of 4ml plastic and tacked them up around the patio with a staple gun. A box fan for ventilation, a filter mask for me and I was ready.

Zolotone

I got "Desert Cameo" Zolotone from the local auto paint supply store. I also got the zolotone primer, clear coat and that silly little spray gun the Zolotone people sell. I masked off the nose wheel, wheel well and landing brake and dived in. First the primer. Damn - they gave me the ferrous primer instead of the multi-purpose stuff I need for fiberglass. It took two days to get this swapped. While I was at the paint shop I picked up a small oil & water filter and a pressure regulator. This was my first ever use of my new gravity feed spray gun and my first use of ANY spray gun for over 20 years. I guess you could say I was the perfect test case. The spray gun worked well on the primer for a couple of minutes, then all I got was air. After a bit of investigation I realized that the little filter built into the bottom of the bowl was clogged. I cleaned it up, sprayed for a while, then it clogged again. I removed the filter and had my surfaces primed in no time.

Next the actual Zolotone. Weird looking stuff. I stirred it up as instructed on the can and poured some into their handy little aerosol spray gun. It splattered nicely, but I wasnt getting very good coverage and the nozzel blocked up every couple of minutes. Eventually, after a lot of messing around and blowing down the nozzel (Zolotone tastes pretty bad) I was able to get a reasonable result. Somewhat dissatisfied, I put the "silly little aerosol" away. I had some paint left in the aerosol, so I decided to try the stuff in a proper spray gun. The instructions on the can say to spray in two steps. One coat at 50 - 60 PSI and a second at 2 PSI. Sounds strange, but what the hell - The first coat went on in seconds BAMM I had a light brown base coat. Now to turn the pressure down. I turned the little pressure regulator almost all the way off and sprayed again. Cool. The "splatter" coat came out perfect and the result looks great. Next day I mixed up a bit of Zolotone epoxy clear coat and sprayed it on. It seemed dry after about 6 hours so I started removing the masking tape. Oops. Too early. A bit of the paint came off with the tape. Next day the stuff was hard as a rock. The resultant finish looks very professional, if I say so myself, and I'm sure it will stand up to almost anything. Also, its smooth and easy to clean. I LIKE Zolotone.

When is it time to say "It'll do!"

Sanding in Florida - at least it saves on the washing If you've read my introduction you'll know that I'm a firm believer in the 98% rule. i.e. You can, with a lot of effort, get 98% of the way towards perfection. The last 2% is 98% of the work. Getting to 99% is almost impossible and that last 1% is simply unattainable. Its kinda like trying to reach infinity. Well, I finally decided I'd hit 98% with my preparation of the bottom. I'd been finding little flaws, touching up and sanding for a couple of months. On May 13th., 2001 everything was ready. Sure - I saw a few minor imperfections as I gave the bird a final wash and wipe off, but I'd made up my mind. This was going to go on forever if I didn't finally say "It'll do!". I steeled myself, ignored the few areas that could really do with a little more touch up, and got ready to paint. After a bit of a search I found Char's favorite glass measuring cup. She couldn't have hidden it from me could she???

I broke open the 1/2 gallon of smooth prime I'd been saving and spend a good half hour stirring it up. I know the instructions say to have it shaken, but I'm sure I got it fully mixed by stirring. OK. I'd waited till the evening to avoid the heat of the day - smooth prime dries too fast in 80 degree weather. [later note: bad plan. bugs come out at night and its hard to see in shop light. Better to get up in the early morning.] It's now or never. Everything's ready. My wheels and any gaps where I don't want paint are masked off [later note - correction. Most of the gaps. I missed a few], the paint gun is tested and clean, the air pressure in my storage tank is up..... time to crosslink the paint and have at it! I dug out the crosslink bottle and found that the contents was one yellow lump. Damn. I have another bottle somewhere - this was the same. I finally found a third bottle on the top shelf, and found a third yellow lump of crosslinker. Damn. I guess it wasn't time to paint the plane after all. I ripped down the spray booth and went inside totally disgusted. Later that evening I went outside again, carefully mixed up a single squirt of dry micro and quietly started hunting around for those spots I'd ignored. Tomorrow I'll order more crosslinker and another can of smooth prime. Next day I called Wicks and told them my problem. The lady on the order desk said there was no part number for crosslinker, but she took a note and said she'd see what she could do. An hour later I got a call from the guy in the warehouse - He needed to know which size kit I needed crosslinker for so he could be sure to send the right bottle. When my order came there was no crosslinker. Damn. Then I found a note saying it would be dropshipped from Polyfiber. It arrived next day. Wow. Wicks service continues to be superb. I'm tempted to try the same call to "that other aviation supply company" and see what kind of answer I get.

Final prime

I was so excited about finally spray painting that I wrote a builder report for the Cozy maillist. Here it is

Technique

Having done both I highly recommend spraying over the paint roller technique. A lot less primer is wasted because the finish is even when sprayed. When you roll it the finish is uneven and you have to "rub off the bumps" to get a smooth finish. I used a conventional (not HVLP) gravity feed gun at 50lbs. Next time I spray I'll water the stuff down a little less than the book says (5parts paint to 1 part water). The goods news is that runs sand off fairly easily. :)

I used a fairly wide spray and put it on just heavy enough so I could see a continuous shine. (the shine dulls off when it dries). Even then I got a few runs. Next time I'll paint in the daytime with better lighting and I'll thin the paint a little less. I'm certainly no expert with a paint gun, but this stuff is very forgiving.

Sanding with 320 grit is almost fun after all the filling and sanding with micro. It took me about 4 hours to sand out the runs, insects and minor lumps and bumps. Next time I won't paint at night when the lights attract the bugs. With a few very minor exceptions the bottom of this bird is ready for final gloss. [Later note: No it's not!]

Quantity

I just sprayed 3 coats on the bottom of the plane (not including wings & canard). This took 1/2 gallon. The polyfiber book says to use 6 coats, then sand. I rolled 3 coats much earlier, sanded, filled, sanded, filled [ad nauseum], then sprayed 2 coats, sanded, sprayed 1 coat, sanded. I wish I had enough paint to spray another couple of coats, but 90% of the plane doesn't need it. I figure that about 3 gallons would be needed to paint the entire plane. I may use four because I wasted quite a lot by priming early to see what it would cover.

Coverage

My last sanding before primer was at 180 grit. This was definitely enough. No need to go smoother than this. I had a few areas, like on the edge of the gear doors, where I'd sanded into the glass a bit and created a row of pinholes. There were a few 60 grit scratches that I spotted as the primer went on. I had to give these areas an extra blast of primer, basically flooding it on with two or three passes, then the holes and unevenness disappeared. It took a while 2 finger sanding with 320 to get these areas faired in, but they came out perfect. I wouldn't recommend this technique on large areas of weave etc etc, but it works for a few minor spots. The point being that you can cover pretty much anything with Smoothprime if you put it on thick enough, but it's better (and cheaper) to get to the 98% point with micro first.

Zolotone

After some experimentation I got this stuff working great. Don't bother with the Zolotone mini aerosol. It's garbage. Spray a quick coat at 50 - 60 lbs. with a conventional spray gun. This gives you the base color in a flash. Now reduce spray pressure to 2 (two) pounds. Using the same standard, came with the gun, nozzle. The Zolotone kinda spatters on giving the nice two tone effect. Once this dries, spray a coat of Zolotone clear coat. The result is like a rock and looks great.

The next day

I'd run out of primer, so I had to wait a week for more to come. After my excitement cooled down and I looked carefully at the plane, I decided that the curve from the bottom to the side wasn't quite right. There were flat spots all along both sides from the seat back backward. I used a total of three squirts of micro to round off the curves. More sanding with 180 grit and we're ready for final prime... again. Well, actually, not. Char did a final inspection and found areas on both strakes which need a bit more rubbing down. She's getting really picky these days. I rubbed the areas down... When the paint comes - its going to be a case of "ready or not - here it comes."

How to do the trim work

GC (grey Cat) keeps an eye on quality control. Here she is measuring the NACA duct I've been researching the best way to handle the trim work, stripes etc. One suggestion is aptly named "butt masking" where you mask off the main area, paint the stripe/s, mask off the stripes, then paint the main area. The idea is that the result is a level finish. No bumps between colors. I called John at Polyfiber on a rumour that they were working on a "pearl" finish product. He says they've abandoned the pearl because they dont like the results. He tells me that the butt masking approach is very hard to get right and takes FOREVER. John also said to avoid clear coats (another way of getting rid of bumps) because they "don't weather worth a damn." His recommendation is to paint the whole plane in white top gloss, rub down the trim area, paint the trim in any polyurathane paint, then colorsand. Makes sense to me, and this way I can get on with the white gloss paint and worry about the trim later.

Top Gloss

The big day finally arrived in early June '01. I did a final prep the night before and got up early so I could paint before the breeze and bugs got up. After Smoothprime the Top Gloss looked a bit thin. I did a final wipe with a lint free rag, spotted a few spots that needed rubbing down, sanded these areas, and wiped again. I crosslinked the paint and was about to get started when the breeze woke up and blew my plastic spray booth onto the fuslage. I nailed it up again and put a brick on it to keep it from blowing. One more wipe and off we go. Hmmm. Seems to be going on ok. Not too hard to get a full shine as I go around. I need more light. I worked my way around the whole plane doing the high surfaces like the gear legs and fuse bottome first, then the sides and strakes. I guess I need some practice, the finish wasnt as full as I'd have liked. The main problem wasn't that I got runs, I got diarrhea. Almost every surface that wasnt completely horizontal had excess paint rolling down it. I stopped after 1 coat which used up the quart of paint I'd crosslinked. I looked at the Polyfiber booklet again and checked that I'd followed the instructions properly. I had. I got the paint from a builder who didnt like it. Maybe he'd thinned it. I'll use this stuff up first and find out when I order the next can. Maybe I just need more practice. That's why I'm doing the bottom first. By the time I get to the top of the wings, I should have this down pat. In the meantime, the good news is that Polyfiber say it's no problem to sand out runs. We'll see. I'll be doing quite a bit of sanding when this sucker dries.

Well, I have three words of advice for anyone who spray's Top Gloss and gets runs. Wash it off! Yes, thats right, I mean abondon the job and take a pressure hose to the wet paint before it gets a chance to dry. I wish I had. Top Gloss is something of a cross between rubber and steel. I guess if I'd waited a few months for it to fully cure throughout I "might" have been able to sand the runs out, but I doubt it. What happened was that the "lump" from the run was much harder than the surrounding surface and my sanding took off the top gloss and primer surrounding the bump. I tried various approaches. On a flat surface a hard block sander works ok, but on curves it was impossible to remove the run without damaging the underlying surface. Some runs would come off in one lump bringing the primer with them. Others would kind of "pop" and leave a hole down to the glass. What a mess. It took a week of sanding, filling and repriming to get the entire plane back to a 320 grit finish overall. I started with 320 grit, then gave up on that and used 180 grit in places. In a few spots I even had to use some filler to bring the level back up to the surrounding paint. Remember how I said that sanding primer was a pleasure after micro. Well sanding micro was a pleasure after sanding Top Gloss. I did take the opportunity to correct a few minor items. The port side cowling lip on the back of the strake wasnt quite in line with the strake. I heated it with a hair dryer, bent it and clamped it till it cooled. I had to fill a small dip at the bend, but had been bugging me, and it'll fair onto the cowl much better now. Finally I mixed a tiny bit of Cabosil and went around the plane filling a few remaining small holes and dips. My first shot at cabosil had been too early. The trick is to put on only what's going to stay. Don't expect to sand this stuff. Just fill the nick and get the rest off the surrounding priomer. Cabosil is for filling little nicks and scratches you can't get with filler. It's very smooth and easy to apply, but don't get carried away like I did first time around. Once set it stays, so there had better not be any ridges. You scuff up the cabosil and paint it.

Painting the bottom with Top Gloss - again

This time I experimented with all the possible settings on the paint gun while practicing on a piece of wood. I used a very fine mist with a wide angle at about 40lb pressure. I was determined not to get any runs. I put on three very light coats on with a couple of hours in between each. There were no runs, but there wasn't a shine either. I'd gone to the other extreme. The finish was flat, but very rough to the touch. Basically what I did was "overspray" the whole plane. I didnt dare turn up the gun to get a "full" coat. Instead I just kept misting it on. Call me chicken if you must, but I didnt want to sand any more runs. I'll work my way back up to a "full" coat as I get the hang of it. At least this way the paint isnt wasted and I'm moving forward. When I was done the plane was definately white. In fact it was so white that my eyes were loosing the ability to see where I'd painted and where I hadn't. The polyfiber booklet describes how to color sand. It says I can work my way up to a good shine. After about 6 hours drying I decided to try some 1500 grit (I didnt have anything between 400 and 1500 on hand) to see whether the finish was going to be ok. In some areas I had to use 400 to get the roughness off. The 1500 gave me a good smooth flat finish that will, I think, polish just fine. Tomorrow I'll get a full range of grits and the 3M polishing compound recommended by Polyfiber and see what kind of finish I can get. I know they say wait a few weeks, but I'll still experiment a bit and see what I get.

Polishing

Well the polyfiber book said "go out and buy this stuff", so I did. I started on the strake and worked my way through 600, 1000, 1500 and 2000 grit using an electric jitterbug. Next came the rubbing compound, medium, then fine. Then the "finesse II" and finally the swirl compound, all applied with a buffing machine. Phew! After about 2 hours work I had the strake shiny. Not a "deep full shine" to be sure, but it did have some shine. There were clearly a few areas that hadnt seen enough sanding. I went back through the whole sequence from 600 grit to swirl compound again and got it a bit better. At this stage I've given up on "beautiful" and I'm desperately trying to reach "acceptable". After 4 hours on the strake with disappointing results I decided to have a go at the nose. I'd run out of dry cloths, so I went in the kitchen in search of an old teeshirt. Char had just got out a clean teatowel to wipe the counter top. Excited monkey noises got me the teatowel, plus a resigned shrug. I went back to polishing. This time I did it all by hand. I think the nose came up a little better, but it got dark and hard to see the results. Hmmm. I'm wondering if the "it'll do" phase is appropriate here. I could stop now and it would be much nicer than those planes that fly in primer. [but then again - those guys have an excuse for the dull finish] I could rub it all down to 600 and give it some more elbow grease, I could take another shot at spraying the top gloss. I could try a different paint, or I could go to a professional. Hmmm. I think I'll sleep on it.

When it came time for the late evening inspection Char tried to be nice, but agreed that the results were unacceptable. Not only were there imperfections in the paint, but there were also a few flat spots around the curves of the nose. I polished the small nose cover and noticed a small quarter sized imperfection similar to a few I'd seen on the strake and nose. It was the edge between two layers of paint. I think what's happened here is that the paint layers are way too thin. In a couple of spots I'd polished through to the primer. It doesn't take much polishing to get through the first layer. This makes sense, since I didnt get a "full" coat on each time. I decided to rub the plane down to 600 and give it a couple more coats. Next morning, in the sunlight, the finish actually looked pretty good at first glance, but the 600 grit came out anyway. Disappointing, but this was definately not one of those "it'll do" times - at least not for me. Besides not feeling happy about the current finish, I want to get my technique right by the time I get to painting the top. I rubbed the whole plane down with 600 grit, then decided I needed to go another level and redid it with 320. When the parts I polished were shiny, I'd noticed a few irregularities or dips about the thickness of a coat of paint. I decided to try the "guide coat" method again. I sprayed one side with a mist of black laquer, then started sanding again. On the strake the black came right off with nothing left. Either I'm doing it wrong, or there are no dips there. On the side there were a couple of spots that stayed black. I mixed up a squirt of micro and applied it to the flat spots with my putty knife. In some areas I couldnt see or even feel a dip, but when I scrapped micro over the area I left a small irregular area. If I scrapped again from a different direction I got the same shape of micro left. I was definately filling a dip. I used about half the micro on the fuselage. What was left I used to fill some visible weave on the winglets. Next day I sanded the micro with 320. Using micro for such small fill goes against Jeff Russell's advice [and Jeff Knows his stuff], but it seems to work for me.

Eventually, over a week after my failed second attempt at spraying top gloss, I was ready for the third. I'd even gone down to 180 grit in a few areas. Oh, by the way, I made another mistake during the prep stage I forgot to mention - After painting the inside of the landing brake and wheel well with Zolotone I didnt want any spay to go down the edges, so for some crazy reason I decided to use silicone to mask the joins. Actually I think this will work well AFTER the gloss paint is done because it seals all the joints. Unfortunately gloss paint doesn't stick to silicone. Once I realized this I decided to take the silicone off for the third round. I'd picked and cut for a while and needed to blow away the debris. The high pressure air hose blew the debris away just great. Unfortunately it also blew away a few dime sized areas of paint right down to the glass leaving a ragged edge. Ugh! I rubbed the edges down and added micro to bring the level back up.

Finally [I keep using this word out of context] I was ready to reprime. I got everything ready for an early morning paint session. When I got up and looked at one of the strakes in the morning light I caught a dip. Me. I'd missed a large area near the inboard front where the shape wasnt quite right. I spent 10 minutes walking back and forth comparing the shapes of each strake. Yep. Definately needs some fill there. Another two days went by while I filled, sanded and filled and sanded again in this area.

Canopy

Since I had to wait for the micro to cure on the strake, I got the canopy from it's hiding place and began prepping it for [final] primer. I'd spent a lot of time finishing the canopy earlier, and now the effort paid off. Even with the enhanced acceptance criteria I'd developed, and adding an extra level of perfection because of it's visibility, it didn't take much work to get the canopy ready for final gloss. On June 23, '01 I had the underside, the canopy and all the covers ready.

Another Cozy visit

Augusto and his friend from Miami brought their girlfriends to see the airplane they plan to build. We had a good visit and Augusto took lots of pictures. When they were leaving they asked if they could come and watch my Cozy fly. I made them a deal. If they turn up and are still dreaming, then they can watch me fly. If they're building, then I'll take them for a ride.

Snow in South Florida

It was time to try Top Gloss again. This time I'd got the hang of the gun. As I began spraying the canopy it started snowing. Snow in Florida, you ask! Well, not exactly. True to my policy of doing everything wrong as a service to those who follow, I had masked the canopy with plastic. Paint doesnt stick well to plastic. The force of the air gun was enough to blow the dried primer off the plastic in sheets. It broke up in the air and settled gently on my new paint like snowflakes. AGHHHHHHHH! I wiped the snowflakes off with a damp cloth and masked the plastic with newspaper. I turned down the volume on the gun and two coats went on with only one small run. When it dried it was a little blotchy here and there where I hadn't applied enough paint, but the overall finish wasn't at all bad. I let this dry overnight and then sanded it smooth with 600 grit. Next day I was ready for the final coat. I only had just over a pint of Top Gloss left which was, in fact, enough for two coats on everything. It could have done with another coat, but I wasn't about to wait a week for it to come. I was examining the first coat while waiting for it to dry when I noticed that a small bit of the Palm Beach Post weather forcast had folded over in the wind from the gun and was stuck on my paint. I peeled off what would come off. After about an hour of drying I was able to get the rest off with very gentle use of 600 grit. Phew! Once the second coat had had an hour to dry I cut carefully along the edge with a razor and peeled off the masking tape. I walked around the plane and examined the result. Not bad. I've definately seen worse. Once it's color sanded and polished I think this will be quite acceptable. As we sat in the hot tub that night I swear the plane got more and more shiny as we watched. They say it "runs out" during the first few hours and that seemed to be the case. In my (limited) book it went from "not bad" to "pretty good" all by itself.

Enough of this finishing for a while. I'm going to make a cowling.

Color Sanding

After a couple of weeks making the lower cowling I decided the Top Gloss had had long enough to cure. Their instruction book used to say "at least a week". In the revision they changed this to "a few months". It's summer in S. Florida. Two weeks will have to do. The first thing I noticed was that the duct tape I'd used to mask off the cowling had taken off the gloss paint in a few spots when I removed it. Damn. Actually, this is no big deal. Top Gloss is supposed to be easy to touch up, and I'll be painting the cowling anyway. I guess two week old duct tape is a pretty tough test for any new paint, so I won't judge Top Gloss too harshly for this. There was also one spot where I'd failed to remove the silicone from around one of the landing lights. Instant paint peel for 1/4 inch or so.

I started in with 1000 grit per the Polyfiber book, and the shine disappeared. A blind person could (and probably should) do this. The change in texture when the 1000 grit sanding is done is very obvious. You feel it and hear it more than you see it. I used a flat rubber sanding block, followed up by hand sanding. The bottom of the plane took me about 3 hours. I found a few minor blemishes. These were mostly embedded insects which had settled on the paint while it was drying. Most of them sanded out with no problem. On one spot on the landing brake a mosquito had landed early in the drying process. I could clearly see the legs, wings and body. After color sanding 1000 grit most of it was gone, but if you look VERY closely you can still see a mosquito shape. I could paint over it, but I think I'll leave it there as a warning to other bugs, and as a memorial to all the Florida bugs that gave their lives during the building of this airplane. Perhaps their spirits will help it fly higher and faster.

After 3 hours of 1000 grit it was 12pm and my arms were tired, but I'd done the whole plane. Next day I graduated to 1500 grit in the morning and 2000 grit in the afternoon. The shine was starting to come back. Now it was on to the compound. First medium, then fine. I've discovered what to do with all the old tee-shirts I've ruined doing epoxy. Use them for polishing cloths. You get through a lot of polishing cloths doing the polishing. I tried using the polishing machine I'd bought. It's the orbital kind that'll stop turning if you hold it. I didnt like the results, probably because I dont have the proper pads for it. In the end I resorted to hand polishing which seemed to work fine. After the fine compound came the Finessit II which really brings up the shine. Finally the swirl remover and the wax. Counting the wet & dry that means I've covered the whole plane eight times over a period of four days from a distance of 1 foot. In my travels I've seen areas where the paint has got too thin and you can see the primer, I've seen dings, dips, embedded bugs and various other imperfections. But... when I stand back the overall finish looks pretty good. I guess it could be better, and I hope the top WILL be better, but it'll do. One particular ding that I may actually fix was caused when my overhead light fell down and impacted the belly just forward of the landing brake. Painted, color sanded, polished and waxed.

If you see my plane one day, and examine the finish on the bottom really closely, then you'll see these imperfections as well, because they're still going to be there. I'll make you a deal. If you spot a flaw in the finish, then show me you're plane and I agree that it's better, then I'll buy you a beer. You've earned it.

Time to flip the plane again

This time I needed to be careful. I didnt want to scratch the plane or make any dings in the new paint. I made a couple of half wheels and fixed these to the wing attach points with 2 * 4s and long hardware bolds. These will support the plane as it rolls and avoid damage the rudder linkage on the firewall or the cowl lips. Once I was ready I called Bulent, Todd and Dan. There will be a plane flipping pizza party at our house on July 12. Bring a (strong) friend. We'll flip the plane at just about the time my daughter, Vicky, takes off to fly to Townsville in the land of oz on a student exchange. By the time she gets back I hope to have this plane flying.
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