QuickTalk 5 - QUESTIONS & ANSWERS

Q: The Q2 prop that has been supplied to us is a 45" pitch prop. According to our calculations, the maximum airspeed possible with zero drag would be 138 mph. The calculations are as follows:


<45"(pitch) x 3250(rpm) x 60(min./hr.)
= 138 mph
12(in./ft.) x 5280(ft./mile)

We contacted our local distributor about the above; the response is below. We have indirectly heard comments about the above from two gentlemen who should be "in the know" about this subject. One is an aircraft designer and the other has a company which manufactures props. Both gentlemen, as I understand, would disagree with the attached. We would appreciate comments from other members. (Jeff Gullickson, #2453)


SUPPLIED FROM QUICKIE AIRCRAFT OF MINNESOTA

Some of you are concerned that the prop supplied with the kit is not capable of normal cruise speed. We asked Mojave about it and the following is part of the reply:

"It is not practical to compare props and calculate achievable speeds using the pitch values that the prop manufacturers call out. This is because different manufacturers use different geometric reference to calculate pitch; some use the flat bottom of the airfoil, others the line of zero lift, etc...

The prop supplied with the Q2 kit is oriented more toward climb than cruise. This is to assist the builder on his early test flights where takeoff and climb performance are more important than high speed cruise. The furnished prop should still provide 160-170 mph TAS without overreving the engine."

We'll know soon enough if there's any problem.


Q: Does anyone know of any tires without knobs that fit the big wheels on the Quickie? (Jim Stoveken, #204)


A: With respect to Craig Strangland's comments(Letters, Issue #4) concerning "wet" wings - I learned a trick many years ago that I passed on to local sail boaters and found recently it is a wide spread practice in small racing sailboats. The trick is to make a slick surface shed water quicker by sanding the surface with 600 grit wet or dry paper until dull. We all like to see shiny-waxed surfaces, but water beads on this type of surface. I strongly suggest the liberal application of 600 grit paper to the canard be tried to eliminate the problem of water beading. If it does not help, simply buff and rewax. If it does help, keep the canard clean by wiping it off with 600 grit paper every few months. (Roger Luebke)


Q: I am interested in installing a Continental engine in my Q2 and would like some advice. Is the firewall moved back because of the heavier engine and if so, how is it done with the canard so close to the firewall? (Don't forget the oil tank hanging down so far) Can the original cowl be modified to fit the Continental engine? Can the battery be safely stored back in the tail for the correct CG? (Ron Gowan, #2421)


Q. Aircraft Spruce sells "RAEF" epoxy that sets up in less than half the time of regular Safe-T-Poxy. It's exotherm heat would be much greater than the other, and probably shouldn't be used on bare foam, but is there anything wrong with using it for flox joints? (Saylor Milton, #2484)


A: You are correct that the exotherm problem is much greater and care must be exercised to avoid heat damage to adjoining foam. There are some drawbacks to using these older epoxy systems. One of these is their increased toxic content. Skin sensitivity was recurring problem in the early days of homebuilt composites. A second disadvantage is that RAEF requires a different resin-to-hardener ratio than Safe-T-Poxy. As a result, the builder must have two sets of measuring equipment and be alert as to which one applies. To answer the question, there is nothing wrong with using this epoxy system, but beware of possible complications.


Q: What about finishing the surface of the vertical fin before mounting it to the fuselage? Wouldn't it be much easier to do while you can lie it down on a workbench? (Saylor Milton, #2484)


A: Yes, indeed. In fact some builders have extended the same idea to the wings and canard. They have found it easier to finish the surfaces before joining to the fuselage. Builders are cautioned to avoid finishing those areas which will have structural tapes applied later on in order to obtain good glass-to-glass contact.


Q: I was disappointed in the "fix" offered for the Quickie electrical system problem in Issue #3 of QUICKTALK. I am sincerely grateful to Richard and Neal for bringing the situation to our attention in the #2 issue, but the solution offered just does not satisfy my personal safety standards. What I really wanted to see was a modification to the Quickie electrical system that solves

I'm not an electrical engineer, but it seems logical to me to replace that part of the system that is giving us the problem - the voltage regulator. Since we use a motorcycle battery, I decided to investigate the possibility of using a motorcycle regulator. My local Harley-Davidson dealer sells a heavy-duty regulator that will handle up to 22 amps and automatically provides a trickle charge to the battery. It is wired into the cycle electrical system just like the Quickie. The price tag is $77.90, which is a little steep, but my peace-of-mind is worth that.

Before I spend my money on the Harley regulator, I would like to ask the QBA members if there are reasons why this would not work and solve the problem? (Terry Hall, #196)


Q: The part number of the Quickie rectifier/regulator in Issue #2 is incorrect. We ordered the part number in the article and it was different in appearance and function. Can you tell us the correct part number? (George Vames, #373)


A: (From Neal Current, #399)-The numbers and manufacturers were interchanged and the no. 10640-00-A should have gone with Phelon. Second, the ONAN 191-1206 should not have been included. Our personal regulator was in a box marked 10640-00-A and was stamped "ONAN, 1079, 14V 20A". A letter to Phelon was at least answered to this extent - they said the 10640-00-A is a 12V 15A regulator". But their letter also included a sketch of the unit and the connections so I can tell it's the same as ours and has the 10640-00-A number.


Q: I am one of the victims of warped trailing edges on my main wing. The edge makes an upward bow from the aileron edge to the wing tip of about 1/2". Any idea what to do now - after final cure? (Bob Shellon, #10005-Can.)



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