SonexBuilders.net

Just to introduce myself, I'm Gregg from Michigan. I currently fly a Kolb Firefly which I built myself (from kit). For those not familiar, it is a very sturdy 3 axis fabric covered ultralight flying on 40HP in a pusher configuration. I have been flying it for 4 years now and am very pleased with it. I regularly fly to pancake breakfasts weather permitting or just fly around some of the scenic areas we have available in Michigan. However, I've been wanting something to get me down the road further, carry a passenger if I want, and not have to have perfect no or low wind conditions to be able to fly. I have had my eye on a Sonex for a couple of years now and finally have the means to take the leap. Why did I choose a Sonex? COST was a big factor in the decision. There are still a few average joes out there that like to fly and 100K for an Airplane is out of reach if you still want to eat and make a house payment. Second, my Firefly used pulled rivets in it's construction and I already have some experience with them as well as trusting their use in the design. Third, there seems to be a lot of information available for Sonex building, this forum being an example as well as factory support and builder websites. Fourth, the Aerovee engine. A big cost savings there as well plus the fact you get to build that yourself as well and add to your knowledge. Now the down side. I have no sheet metal experience nor engine experience. I've done some tuning on my Rotax for the Firefly and it's doing fine but some of the anomalies of the Aerovee have me a bit nervous, the fuel burp being one and tuning of the Aero injector being another. Dimpling and countersinking will be new as well. I've ordered the Sonex Dimple Die tool which is 120 degrees but am reading some conflicting information on whether you have to have a 120 degree countersink or a 100 degree is still OK to use. This kind of stuff is where I'm sure I'll be bugging the members here for info. I should be receiving my New Sonex B Kit sometime later in December. The adventure begins......

Gregg K

Welcome to the fold Gregg! I think you'll find the Sonex kit and community to be outstanding. This was my first project, so I got the tail kit video from homebuilthelp and found it to be very helpful. Looking forward to seeing your project!

Gregg. You will most definitely want to use the correct countersink for the corresponding rivet. Do not mix these up for build quality and safety issues no matter what you here from others who say it is OK. It's not. Second, where about are you located in Michigan? I met a Sonex builder a few years ago up in Gladwin. He was building his Sonex in Sugar Springs, Gladwin. It would be good for you to have another experienced Sonex builder, or any experienced and knowledgeable home builder nearby to lean on for support and get eye's on your project early on when you begin. I have seen examples in the RV aircraft community of workmanship that I would not consider airworthy. This simply because they thought they were doing it right all along but no one was there to take a look and tell them different. Good luck on your new adventure! Dave

Gregg,
Welcome. The Sonex is a great kit. I would not worry about what you don't know yet. Just accept that you will make mistakes and you will have to do a few things over. That is part of the learning process. Join a chapter or find an experienced sheetmetal builder. Not hard to learn - at the airframer where I used to work we had former Taco Bell employees we trained to be aircraft assemblers. You will need a 120 degree countersink.

Thanks for the responses. I'm 40 minutes north of Grand Rapids. I plan on joining an EAA chapter in Grand Rapids. They have built several RV's there with another one under construction right now. I have a couple of chapters that are closer, but am not seeing much activity on their websites. There are a couple of Sonex's under construction around these parts according to the factory webpage and I hope to hook up with at least one of them in them future sometime. As far as the countersink, I'm reading that a single flute is really the best choice for a clean finish with no chatter but I can't find any 120 degree that fit a microstop cage. I can find 120 degree 3 flute for a microstop but am reading that they don't do as nice a job and leave a rough finish (risers?) Let me know if you have a source for a single flute. I have some leftover metal from the firefly project that I can practice on. I'll have to wait to receive the dimple die tool in the kit for that. In the meantime, I have a bunch more clecos, new drills etc that I have to order while I'm waiting. This winter has gone from hibernation to as much work as I want now. Sweet...!

Gregg

You can find 120 degree countersink bits, threaded for microstop cages, #30 drilled holes (and many others) at Browntool:

http://www.browntool.com/Listview/tabid/344/CategoryID/65/Level/a/Default.aspx

Three flutes will chatter - if you countersink freehand. Don't do that! When the microstop is properly set, and you finish up the countersink with pressure on between the cage and the part, it will come out smooth. I have only used a single flute counterbore for wood screws and I have been at the homebuilding thing since 1990 or so.

Hi Gregg,
I am currently building a Waiex (a Sonex with a V tail) in Ann Arbor, Michigan. Airframe completed, motor installed, beginning electrical installation. I would be glad to show you my project and answer some of your questions.
Feel free to contact me at: debruet@yahoo.com.
Regards
Renaud Guibert
Waiex # 0161, TD, Turbo AeroVee

Don't worry about the three flute countersinks in the micro stop tool. They will work fine. I used them for my Sonex.

I used the single flute countersinks in my RV-14 and they are nice but I never found any 120° versions, only 100°.

Thanks for the invite Renaud. I have sent you an e-mail. There is a picture attached so if you don't see something from me, check your junk mail folder. I am definitely willing to visit anybody in the lower peninsula of Michigan to see their projects and tap your expertise. I don't think there are any Sonex owners at the EAA chapter I'm looking at so your help is most welcome. I am retired and have time to travel. I am most interested in completed Aerovee engine installs and projects that might still be under construction.

Regards to all

Gregg Kaat