Q-talk 58 - LETTERS
- Category: Q-Talk Articles
- Published: Sunday, 30 June 1996 07:11
- Written by Tom Moore
- Hits: 1932
I was given a copy of the last Central States Canard Newsletter (VariEZ, LongEZ, Cozy) in which a guy severely badmouthed System 3 paint. He claimed it doesn't hold up, is cracking and flaking off, etc. So I called System 3 to ask them about it. They had seen the letter and sent a response to the individual who sent them the copy of the newsletter.
In case you haven't seen this newsletter or the response, I thought I should send it to you. Since you and I and Dennis Colomb and probably a few others are using System 3, it might be a good exchange to include in the QBA letter. One of our chapter members who is a long time body and fender shop owner commented to me that there are many things that could be wrong in the preparation and that he would like to know a lot more before rejecting the System 3 paint. I thought it was interesting that this guy didn't contact System 3. Anyway, here is his letter and the preliminary response from System 3.
As for me, I now have all the flight controls, the top and bottom cowlings and the tail cone sanded with 320 grit ready for color. After the original roll on coat of System 3 primer, I guide coated the entire airplane to find the high and low spots and sanded it down with a sanding spline to eliminate them. This caused me to sand through the primer in some spots. So I am using an HVLP gun to spray another coat of primer and hand sanding with 180, 240 and then 320 grit papers. It is now smooooooth. I have contacted our local airplane antiquer and restorer who has a body shop and he has agreed to try out the System 3 top coat on some small parts to get an idea of how it handles. System 3 now tells me that they have tested Imron and Centauri over their primer with good results, so that is another option. They also told me that if you wait 20 or more days after color spraying, the paint will buff to a higher luster, avoiding the clear coat.
Bob Farnam, Livermore, CA
SYSTEMS 3 PAINT REPORT FROM THE CSA NEWSLETTER
I used Systems 3 paint for my Long-EZ. It was easy to use since it was water based, but it was difficult to get a great finish for a lot of reasons. I eventually was happy but it took hundreds of hours and lots of elbow grease. That is enough for me to recommend to fellow builders to try another paint. Now, after flying for 2 years, (and always being hangared), the real reason for builders to avoid this paint is that it doesn't hold up. It is starting to craze - thin cracks in the surface that looked like hundreds of parallel razor cuts.
At first they could only be seen with the light glancing off the surface at just the right angle, but now have grown to be visible any time and I will eventually have to re-paint (OH NO!!). In some places, the crazing makes small pieces that then crack and flake off. I had applied the paint religiously in accordance with the manufacturer's directions and with several consultations by phone, so I think it was applied correctly. The bottom line is -- Don't use Systems 3 paint!
(RESPONSE FROM SYSTEM THREE)
Thank you for your July 11 letter enclosing a coy of the letter in the CSA newsletter. I wish I could say "And now for the rest of the story ..." but I am afraid that this is the first time I have heard of a problem with this airplane. For that matter I have not heard of this problem on any airplane, boat and other item painted with System Three's water reducible coatings and it has not shown up in any of our tests. One of these tests involved clear coating prepared aluminum and exposing it outdoors with a 45' south face in the Miami, FL area. There was no loss of flexibility after eighteen months. Another on a fabric elevator panel shows no cracking after two years of outdoor exposure in Riverside, CA.
We have not been contacted about this problem so we have not seen examples of the "small pieces that then crack and flake off". I would want to know a great deal about substrate preparation with special emphasis on the faring method and materials used. If the substrate is not stable any primer and topcoat could easily crack. He describes the cracks as looking "like hundreds of parallel razor cuts". This almost certainly indicates a problem with the substrate. If the paint were at fault by itself then the cracks would be more random since the paint is amorphous. Parallel cracks indicate excessive flexing of the skin laminate/fairing compound. This is far less capable of taking the flexing stress than the System Three water reducible LPU paints. The cracking paint may be a symptom of a serious problem with the structural laminate as flexing here cracks the fairing compound, which, in turn, cracks the paint. Once the paint cracks dirt, oil, water and other materials collect in the cracks and eventually force flaking and peeling through freeze/thaw and other mechanisms. Nothing unusual here. It would happen with any paint.
I'm sending a copy of this letter to the last address we have for him so that he might contact us about the problem. I don't have the CSA editor's address and so would appreciate it if you'd send a copy of my letter to him.
W. Kern Hendricks
Dear Tom and Jim,
Enjoyed the last Q-TALK and wanted to send along to you some information as a follow-up to the notice on the new carbon sparless canard for us Q-1 aviators.
I spoke with my friend up in Oregon earlier this week, and he will be sending me the templates for the canard, as well as the lay-up schedule. He is designing this canard as a substitute for the one requiring the round carbon fiber spar, which is no longer obtainable. As most QBA members recall, only about 16 sets of these in all were made for the original Quickie.
The new replacement design involves the use of Graphite rods, readily available through Aircraft Spruce. The engineer doing the design is currently with Acro-Tech and is working on the G-200 and has much experience in the airfoil design working with a trustworthy computer program. Design limits will be as per the FAR's and will certainly match the strength and flexibility of the regular LS-1. My canard will be the prototype for this new spar-less design and we will do a static load test once completed, assisted by the designer to see how it measures up and for confidence.
We are very excited about the design, as it will enable those building a single place Quickie to fly with the superior NASA LS-1. If anyone would like further information, or would like to purchase plans and instructions for the new replacement, you may direct your inquires to Mr. Chris Bailey at Acro Tech Aviation: (503) 543-7960.
Alan Thayer, Castro Valley, CA
The following is an update on our Q2, N32DK (S.N. 2453). It has the Revmaster engine (Posa carburetor) with .060" shims under the cylinders to lower the compression ratio to 8.5:1 instead of 9.3:1. (The original heads cracked after 74 hours.) We now have 165 hrs on it. It cruises at 135 mph indicated at 900 lbs and 125 mph @ 1100 gross wt. My partner (Harold Dirks) and I put on only 31 hours in 1995. This fall we pulled the engine twice to try to get all 8 plugs firing "all the time". Spark plug wires were known to be a problem, but the mags "looked good". We later pulled the engine again to have new points put in the mag. After more testing I confirmed all the plugs are firing but the left mag still has 200 rpm drop compared to 25 rpm on the right mag. We will probably end up pulling the engine again to verify the left mag points were installed correctly.
The other major improvement we made was to build and install a "C" dipole antenna in the tail cone. This was per Steve Whiteside's instructions in the Nov/Dec 1993 issue (#43). It did improve our transmission range! I was able to talk 30 miles at 2,000 agl and previously half that distance would have been a stretch! We did have to install it behind the FS 120 bulkhead, slanting backwards because of interference with our ELT/Transponder ground plane that is located in front of the bulkhead.
Our major cross-country this year was the 1.5 hr trip to the "North Central EAA Fly-In" at Sterling/Rock Falls, IL airport. It was a good trip, and a good day! Admission and parking is free! There were a good variety of airplanes there. Terry Crouch parked his award-winning Quickie right by us. Paul Fisher and his son arrived in their Q200 just as we were leaving!
Now for a follow-up on the leaky header tank. Since we put in the "flox dam" as I mentioned last year and have switched back to Avgas we have had no more leakage problems!!
Charles Kuhlman, Marshalltown, IA
I purchased N72GS after it sat in a hanger for 11 years. I've fixed a damaged leading edge (a ladder fell against it) and repaired a broken tailspring (kids jumped on it). I've changed the carb from a Posa to an Ellison-2. Carb heat and cowling will be the next puzzle to figure out.
Hopefully I'll fire it up and fit the cowl to the Ellison carb. Everything else has been taken care of so it's wait for VFR weather. All your newsletters have been a good way to pass the time 'til then.
John Kalbrener, Yakima, WA
I would like to thank Steve Whiteside for the article on the bent "C" antenna in the December 93 Q-TALK, page 4. I have built several of these for EAA chapter 223 members and find that very flat SWR readings can be achieved by making the tuning stub one inch longer and trimming it back while keying the transmitter in between each trim while observing the SWR meter. The closer you stay to Steve's design the better antenna you will have. All materials were available at electronic and hobby stores at a cost of about 25 dollars per unit.
E. L. Puckitt, Kountze, TX
Another year has gone flying. Sam Hoskins write-up in issue #54 on stuck valves was excellent. My experience matches his. I've had three occasions of need to use the procedure in my 600+ hours of operating N2AM. It's been a different cylinder each time, in spite of the fact that all four were reamed each time one stuck. I found you could tie a thin nylon fishing line to the valve stem groove before you drive it into the cylinder. It was then available to fish out and pull the stem back out the spark plug hole and back into its own guide hole. The local engine shop rebuilder loaned me his guide reamer, which is a standard automotive size for Chevy engines. It was surprising how much carbon had built up.
After my return from Ottawa, I decided to modify my fuel vent system to get rid of overfill blockage. I copied Les Hildebrand's system of separate vents for each tank terminating flush with the fuselage bottom. His worked fine. I wanted to reduce fuel weeping and felt that flush rather than ram air vents might help that.
After three "emergency" type situations just after lift off at 30-50 feet altitude, the engine became very rough. Each time I found something I thought might be the cause, stuck valve, cracked intake hose, etc., only to have the same problem. I finally decided it was fuel vent lines. I made new end pieces and turned them into the air stream for pressure and that cleared my problem.
It seems that at least on my airplane there is a real low pressure area around the bottom side of the fuselage. Moral of they story ... be careful when messing with the fuel system.
Art Jewett, Louisville, KY
I am currently building a Tri-Q. It is not quite 50%. I acquired the project with all the big pieces made except for the canard. It is the LS 0417 Mod and I have assembled it. But I received a pretty big shock while preparing the top side for cover. Now mind you I've assembled the carbon spar and attached the cores and covered the bottom. While preparing the top for cover, I was checking for straightness and discovered that both cores, (BL15/BL48.8) have a .100" sag in the middle! This is the only place that I can find this problem and it's on both sides of the canard! Everything else is perfect.
It is a source of anguish, because it is a bit much to make up. So I think I'll bite the bullet and take it all apart and start over. Among the parts that I received with the Tri-Q was a pretty complete inventory of newsletters dating back to at least '84.
There is a fellow, Brian Martinez, who seems to contribute quite a bit to the newsletters and I gave him a call. He seemed very knowledgeable and about convinced me to start over and build the conventional Q-2. He said that if I install the Matco brakes with independent braking and set the wheel camber/toe-in for zero and make a good tailwheel installation, that it will be fairly tame on the ground and cruise about 20 kts faster.
I have considerable experience with VW engines in an original design of my own, my Sonerai 2L, and a variety of other friend's planes that I've had a hand in. We've had no bad experiences with the VW, (except for two of my friends who were ignorant enough to attempt using the Monnett Super Vee extension!). The engine seems to be bullet proof, if, of course, you know what you're doing with it.
I'm currently building up from scratch a VW engine with the AS-41 alum. case, 87 mm forged cylinders, forged 82mm stroker crank, hydraulic cam and lifters, and the Airesearch AR-3 turbocharger. My plan is to use a 60" prop turning 3100 RPM max. I hope to get a 2 times HP boost with the self regulating turbo, but will derate that by running the engine at the slower speed. There are a number of similar projects out there that seem to be enjoying real success. The benefits when compared with almost any other VW configuration are better take-off, climb, cruise, less noise, and, hopefully, an honest 4 gph performance, not to mention the weight savings when compared to a O-200.
I thought that this was an original idea, but about once every other week or so one of my buddies comes up to tell me about another turboed VW that they heard of or read about (sigh).
I'm seeking advice and conversation with others who might be able to offer some insights and help me to avoid some of the pitfalls of building this particular bird.
Mike Hunton, Goshen, IN
The Fly-In is next week, August 30th thru September 1st. It's going to be a good time!
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