Starting tail kit questions

[DCASonex]

Quick hints: With any of the common pneumatic rivet pullers, cut the trigger off to a length suitable to just two fingers. That allows other fingers to Grasp the tool for better control, and trigger does not require any appreciable force to operate. Use a flow control on inlet so that it takes about 1 - 2 seconds to pull a rivet, then hold tool loosely enough that you can feel it self align to rivet to help insure that all rivets are set properly to surface. Simple flow controls with a swivel built in make it easier to maneuver, and a length of lightweight hose will help insure that weight of hose does not pull you out of position.

For close quarter work, get a not to expensive manual puller, and grind off all the material forward of the barrel, keep this weakened tool for use only when needed, and only with 1/8' or smaller rivets.

David A.

[fastj22]

Harbor Freight puller. Get the extended warranty. I'm on my second one, the first one gave up about 5000 rivets in.

[nosky2high]

I gave up doing it that way after the tail kit and bought a somewhat-low-price rivet squeezer (http://www.aircraft-tool.com/shop/detail.aspx?PRODUCT_ID=ATSRS-1SD) and some good quality dimple dies (http://www.cleavelandtool.com/120-degree-dies-for-1_8-pop-rivets/productinfo/DIECS4-4/#.VorA-vkrKUk) - be sure to get dimple dies that are designed for pulled rivets! The angle for pulled/pop rivets is different from driven rivets. Those two things will get you started, though you'll still need the nail-style dimplers to deal with big parts and skins. Eventually you can grab a C-Frame to dimple skins and other big parts.

NOTE: You'll need some nail-style dimplers in any case, because the Sonex was not designed with flush rivets in mind. Some holes are impossible to get into with a C-Frame or a rivet squeezer, and the tight spaces will actually require you to grind down some of the nail-style dimple dies so that they can fit up near flanges (like wing & tail ribs).

P.S. If you go ahead with flush rivets, here's the drilling sequence that works best:

• Pilot-Drill with a #40 bit
• Align & clamp parts.
• Drill through second item with #40 bit, cleco'ing as-appropriate
• Up-drill to #32 bit, cleco-ing as-appropriate (note that clecos will be very tight in these holes and may not always clamp hard - wiggling them a bit often helps the parts slide in these tight confines)
• Disassemble
• Debur both sides of all holes
• Dimple. This will slightly enlarge the hole, allowing the rivets to fit.
• Surface-prep as-appropriate.

(If you updrill to #30 and then dimple, the holes will stretch and be a bit big for the rivets. This over-sizing is OK in most cases; but drilling to #32 makes for a really nice fit and strong rivet joints. If you dimple before your debur, you will find it very hard to properly debur both sides of the now-angled holes)[/quote]

Awesome advice, thank you Sir.

Who is your source for #32 bits? I can't seem to find them in the usual places, Wicks, Spruce, etc. Are all of the exterior rivets the same size? do I need any other size dimple dies?

Sounds like if I chose to do the flush rivets that I should invest in a C-frame to better protect the parts in addition to the rivet squeezer you recommended.

Another question for you, i currently have a corded drill as my air compressor is small and unable to support an air drill. What corded drills out there are best for doing this project? Is there an rpm sweet spot?

Thanks again,
Anthony

[gammaxy]

Hi,

I just notice you're from Enterprise. I grew up there and regularly fly my Sonex down on weekends so my kids can visit their grandparents. I was down there this weekend. I believe there's a Sonex/Waiex based at the field.

I built my airplane with two of these Harbor Freight corded drills:
http://www.harborfreight.com/38-in-vari ... 60614.html

For drilling sheet metal, you don't need a lot of torque, but high rpm is nice. I definitely recommend a drill with a keyless chuck. The Harbor Freight corded drills are so cheap, you could get one for every common drill bit size and never need to switch bits.

Since finishing the airplane, I bought a cordless drill and wonder why I didn't just get one sooner, though :-)

Chris Madsen

[NWade]

Awesome advice, thank you Sir.

Who is your source for #32 bits? I can't seem to find them in the usual places, Wicks, Spruce, etc. Are all of the exterior rivets the same size? do I need any other size dimple dies?

Sounds like if I chose to do the flush rivets that I should invest in a C-frame to better protect the parts in addition to the rivet squeezer you recommended.

Another question for you, i currently have a corded drill as my air compressor is small and unable to support an air drill. What corded drills out there are best for doing this project? Is there an rpm sweet spot?

Thanks again,
Anthony

Anthony - You're welcome!

A C-Frame is nice; but if you want to limit your expenses you can certainly get by without it for the tail build (then get it before doing the Wings & Fuselage).

You should be able to find good #32 (or even #31) drill bits at a good local hardware store. Not a Home Depot-style improvement warehouse; but an old-school honest-to-goodness Hardware store. Several Aircraft supply stores sell them online, too. Here are a few:
Cleaveland Aircraft Tool
Aircraft Tool & Supply
The Yard
...Also, some places like McMaster-Carr sell them (though not at competitive prices for small quantities).

As for rivet sizes: The only place you'll find a different size rivet is in the wing spar, and if you do any "aftermarket" mods (like a Duckworks wing/landing light). There are some rivets you might want to use on the Fiberglass parts that have a broader head to them; but I haven't worked with those yet and can't claim any expertise with countersinking or dimpling for them (I'm going to do all of the fiberglass bits at the end of the build).

Regarding drills: Air drills are noisy and take a lot of air; but they are LIGHTWEIGHT and HIGH RPM. Those are the two qualities you want most. I started out with some harbor-freight-like air drills, but eventually I sucked it up and bought a $100 "ATS Pro Palm Drill" online. I'm really happy I did, as the lighter weight saves on hand/arm fatigue and makes it easier to line things up for perfect vertical/perpendicular drilling. You can use corded drills and they'll work just fine; but they do tend to be heavy. Whatever you use, higher RPMs is better - and this is the one major knock against cordless drills. I use a Makita for some parts of my project; so its not like you CAN'T use a cordless drill. But their slow RPM range (usually less than 1500 RPMs) makes for a slower process, and the holes tend to turn out more ragged/uneven as the bit "tears" through under heavy pressure - rather than carving small chips. This is fine for pilot holes; but when up-drilling to the final rivet-sized hole I would much rather have a corded or air drill, to make the work faster and the holes more precise. (Pulling rivets through loose/oversized holes is a pain... At the least you have to knock the stem back down into the rivet with a pin-punch and hammer. At worst you have to drill it out and replace the whole thing with a larger rivet)

Now I will state one more time that you CAN build a Sonex with just about any kind of drill. People here have done so. The question is - as always - how quickly do you want your build to go, what is your budget like, and what factors are important to you (for example: if you have tendonitis or other problems that would make holding a heavy drill a bigger deal than it is for the average joe).

Hope this helps!

--Noel

[mike20sm]

http://www.harborfreight.com/air-angle-die-grinder-32046.html

When I was at a workshop I saw one of the Sonex Employees building the new drone wings using an air grinder. It's light, High RPM, and ergonomic due to the 90 degrees. The one thing I forgot to note was how they chucked up a small drill bit in the larger collet.

[WaiexN143NM]

Hi All,
For someone starting a tail kit , u may want also to buy the Sonex(sorry no waiex yet) tail kit build video from www.homebuilthelp.com
It is a step by step construction video to build the tail.
They also have a complete airframe build video series for the Onex.

WaiexN143NM
Michael Radtke

[Bryan Cotton]

I have a Milwaulkee corded drill and it is awesome. Turns a very high speed which is good for aluminum. The downside of corded drills is that most of them spin a while after you release the trigger. Air drills are much better in that regard. Air drills have two strikes against them though - the hose and I can't hear the radio. I use my cordless drills. Still, there is no shame in using what you have got. It will work!

[samiam]

Ahh the drill debate. I went through this for a long time. You will figure out what works best for you. I have the HF cheap corded drill pictured above. It works, but there is a lot of slop in the chuck so I was not as pleased with the results. I bought a nice Bosch 12V Cordless that is compact and lightweight, with 2 Lithium batteries. Works amazingly well, the batteries last forever. I never use the air drill because I don't like the compressor noise. When drilling the wings or something I'll probably use it though because of the sheer volume.

I know that it's taken as gospel that faster speeds are best for aluminum, but I have found that using good quality sharp bits is the primary factor in my hole quality. If you have to push at all, throw it out and pop in a new one.

[NWade]

I have found that using good quality sharp bits is the primary factor in my hole quality. If you have to push at all, throw it out and pop in a new one.

I agree 100% with that. Drill bits are cheap and disposable. Throw them out, or put them in a special container for around-the-house projects; but a bit that's even slightly dull is no good for aircraft.

On a separate topic... Anyone starting the Tail Kit is probably a first-time homebuilder. If you aren't going to make it to a Sonex workshop, then I have two strong recommendations:

1. Go on the EAA website and look for a SportAir Workshop in your area. The Sheet Metal Basics course is WELL worth the time and money! It will give you a great running start at making good parts and good rivets. You'll waste fewer parts and have a lot less frustration.
2. Buy Ron Wanttaja's book "Kit Airplane Construction" (preferably the 3rd Edition). Its available on Amazon or from many aircraft supply companies. This book goes over a ton of the basics of wood, metal, and fiberglass aircraft construction methods. It helps you understand things like edge-distances, how to avoid/minimize cracking & corrosion, how to understand the odd number and letter systems that describe nuts & bolts, etc. Its very good stuff!

Take care,

--Noel