Hatz Biplane Association

3003 is way to soft. If you do not want to use 2024 use 5052 or 6061. I used 2024 - T3 and had no problems.

Michael
N838MM

Thanks for that input Mike. Is this a great group or what?

Bill

Before beginning the actual ailerons I made a short section of aileron (approx. 18") to practice the skills and make a few mistakes that won't show up in the final product. This act proved to be quite helpful as actual fabrication progressed.

I built my own press according to the old EAA article and used .016" 2024T3 for the skins. The end caps and ribs are 3003-H14 ( a joy to work with) and instead of the wooden wedge trailing edge I am using Cessna trailing edge bulb. The trailing edge will have a nice finished look and less chance of people losing skin on the diamonds. The aileron spar is 032" 2024-T3 which is a bear to work with unless you have full scale tooling. I have a 30" combination press - break - roll and made the spar in two sections with a doubler. Once I determined the bend radius my press produced, the calculations were pretty straight forward. I know a couple of people with machine shops and large breaks but why let them have all the fun.

Back to the aileron press, I had to C-clamp a heavy piece of angle iron to the top of the press and install extra thru bolts at the corner joints. I used an 8 ton hydraulic jack for pressure and ran each skin through the press twice, reversing first end in, to neutralize any variation from the first pressing. If I were to do it again I'm pretty sure I'd save my pennies and find a source for the skins rather than press my own. I like the fact I made my own but I have a feeling mass produced skins would be more uniform.

Overall building the metal ailerons has been a real skill builder from layout to, calculation of bend allowance and having the aileron fit without interference. I'm also using the extruded hinge and the internal pieces get alodine treatment. Still working on the first of two ailerons after 3 weeks part time.

NOTE Has any one built the Hatz Classic with the slave aileron design shown in the drawings? I think the steel brackets are too far from the leading edge. I have looked at ever picture I have of the classics and it looks to me they have used a surface mounted bracket that is closer to the trailing edge. Any experience with this method?

Thanks

Michael
N838MM

I used the more rearward location for the slave strut fittings with a wooden block to act as backing. An irritant for me has been slave struts out of plane with the interplane struts so spent a lot of time getting everything orthogonal. The other challenge for which a solution did not present it self was minimizing differential between upper and lower ailerons. In the end simplicity took precedence.

JohnKerr, anxious for warmer weather.

Thanks for the reply. I have come to the conclusion that the design shown in the classic plan will not work. I am going to use a surface applied bracket that I can move around and test fit before the actuall installation.

Michael
N838MM

these pictures may help you. These fittings were made from 1/8" angle. Not shown are backing plates and of course the would filler block in the aileron.

John Kerr

Perfect! That is what I plan to do.

Thanks

Miochael
N838MM

Well thanks a ton, gents. That answers a lotta questions. I'm curious about the slave strut brackets though. I haven't gotten there yet. What is the problem there?

Nick

I had the same differential issue when setting up the aileron slave rods for my 25% scratch built Waco YMF-5. The Waco has a diffent type of flush mount bracket that traps the slave rod inbetween the bracket. The bracket on the top of the bottom aileron faces one direction and the brackt on the bottom of the top aileron faces the other. They are the same distance from the T/E of the aileron but the bracket direction corrects the differential. I set them up on my model the same as the full scale and the aileron differential issue was resolved. The bracket resembles a wing from a toggle bolt nut which is what I used on my model.
See the atatched pics of my model slave rod setup. As you can see I like classic bipes.
Anthony