aviation: lightweight high speed air drill

[vavet]

I know we have a few people involved in aviation related activities here. I'm hoping to solicit input from cvairwerks and another gentlemen from the Savannah, GA area who, IIRC, is also building an experimental aircraft.

I've had my Sonex plans for 21 years, but I've recently started working on it in earnest again. I have a cheap Kobalt air drill. It seems to work fine, but I've heard some people say that until you use a really nice, high-end air drill, like a Pan American or Sioux, you don't know what you're missing.

I'm wondering what you guys have to say about this. I think I paid about $40 for my Kobalt drill. One of those really nice drills is about $200. That's quite a premium, but I'm also going to be spending quite a bit of time with this tool.

So tell me...what am I missing?

 

[sberry]

There will be opinions on the best drill. If it makes you feel more handsome go for it,,, but, there is a huge difference between diy and production or steady maintenance. Seems like there would be enough to find to spend on with this type of project?

 

[Citation]

Check out Pan American Tool's Nova line.
https://www.panamericantool.com/nov...p-drills/novar-compact-pistol-grip-drill.html
Think about what speed you need. The person who introduced me to these drills has both the 2600 and 4000 RPM drills.

 

[Air21]

Pan american rates favorably against Sioux, but almost anything will build one Sonex. A guy in my EAA Chapter did the whole thing with Harbor Freight tools and didn't complain any more than usual.

 

[cvairwerks]

I'll have to see what we have at work these days. I've been away from the factory side of things for about 18 years now, so not up on what's in there.
I haven't played with Nova's before but should be good. Look at the the 60-310, about $120 from PanAm directly. It's a compact drill, keyed chuck and 4K rpm. Even with that rpm, you won't get close to optimal cutting speeds, but you will do well enough.

For bits, go to someone like MSC Direct or similar and look for US made, jobber length, oxide coated, 118 degree bits. Buy them in full packages. You'll go through more of them than you think, but with some care, they will last hundreds of holes. Chicago-Latrobe or Cleveland's are the ones we purchased the most at work and is what I buy for my shop. At some point you may need a few 6" and maybe a 12" or two, but not always necessary.
For critical holes in hard to replace parts, I often use to use a #50 bit for my pilot hole. Reason was, if I needed to move it some, it's way easier to pull a #50 than a #40 or #30.....

 

[klitzke]

Hi, Vavet!

I think you will find the most value in a pan american tool drill. These drills are absolutely comparable to the high end names. There are some good recommendations here in the comments and I’ll just add my two cents on the version I own.

I have the pistol grip non reversible and used it professionally for several years in aviation. I bought the 3200 RPM which seemed to bridge the gap between your 3/32 and 5/32 rivet sizes. I was extremely happy with the value and performance! You haven’t been lied to - a decent air drill is worth the cost.

Two things for you to consider: buy used and get a quick change chuck. First off, EBay has a ton of great deals on the Sioux palm drills. If you choose this route be patient and make sure you find one that has been taken care of. Second, take a gander at setting up with quick change and threaded drill bits. I went this route for flexibility during large repairs - it took seconds to change out my bit! I also bought an angle drill that took threaded bits so I could work with a common set and be more efficient.

A large project like this can absolutely be done with cheap tools that “get the job done” I never disagree with the naysayers on that. But the ease of use with the quiet and smooth operation is worth something. Is it worth and extra $80-$100 dollars? In my opinion - yes!

 

[kmacht]

An expensive air drill is a waste of money on a Sonex. I scratch built mine. I started out using an air drill but constantly having to deal with an attached air hose and the noisy compressor far outweighed the few extra seconds I saved drilling a whole sheet of holes. I switched to using a cordless drill and never looked back. With some of the light weight cordless drill options and long battery life available today you would be foolish to sink $200 into an air drill. Now the pneumatic river gun is a different story. The $40 one from harbor freight is with every penny unless you want forearms like Popeye by the time you pull the ten thousandth rivet.

Keith
Sonex #554

 

[cvairwerks]

A couple of problems with using a cordless... They are a couple of times bigger than a palm drill. Lots of places you can’t get access with them. Weight....a cordless is 2-3 times heavier than an air drill. Doesn’t seem like a big thing, but after a few dozen holes, that light weight air drill looks better and better. Speeds...about the best you will get from a cordless is 1500 rpms. For a #40 bit, you need to be running every bit of rpm you can get. SFM of the outboard cutting tip needs to be high for aluminum....Low rpms don’t cut well in aluminum snd especially with 2024 and 6061. Both can be gummy and cause bit grabbing. Only our big Thor drills and our Quackenbush auto drills had a max rpm under 3000. The Q’s required 1/2” id air lines for the motors and a 3/8” line for the coolant feeds.

 

[kmacht]

In a production environment you are right about an air drill but on a Sonex the speed makes very little difference and other than the spar pins there wasn't a single place where my cordless drill had trouble getting into. There were many times where an air line got in the way when using the pneumatic puller though. The money is better spent on buying a whole bunch of 3/32 and 1/8" drill bits and replacing them every time they get even slightly dull.

Someone building a Sonex isn't typically building more than one or two of a single part. They also aren't normally working 8 hours day every day on the project. Most builders spend maybe an hour or two a night and maybe a few hours on the weekend working on it. The benefits of trying to apply the same tools and processes used in a mass production environment just don't apply. Sure, there are few downsides to using a $200 air drill and if you want to use one go for it. Just don't think it is going to make the build go any quicker or easier. Think cost benefit ratio.

 

[ttpete]

A couple of problems with using a cordless... They are a couple of times bigger than a palm drill. Lots of places you can’t get access with them. Weight....a cordless is 2-3 times heavier than an air drill. Doesn’t seem like a big thing, but after a few dozen holes, that light weight air drill looks better and better. Speeds...about the best you will get from a cordless is 1500 rpms. For a #40 bit, you need to be running every bit of rpm you can get. SFM of the outboard cutting tip needs to be high for aluminum....Low rpms don’t cut well in aluminum snd especially with 2024 and 6061. Both can be gummy and cause bit grabbing. Only our big Thor drills and our Quackenbush auto drills had a max rpm under 3000. The Q’s required 1/2” id air lines for the motors and a 3/8” line for the coolant feeds.

At a flea market, I picked up a very small air drill with a 1/4" Jacobs chuck. It's an early CP with a guard around the chuck. It runs at 3000 rpm. I think it was a take-home from a WWII aircraft plant because it was in almost new condition. The closest plant around here was the Ford Willow Run plant. It's my go-to for fab work on aluminum.

 

[Fly YX]

I know you looking at air powered drills but I have been using this one for a few months now and have not had any problems. Its 4000 RPM The only time I use air anymore is In the fuel tank.

 

[Paul_The_Builder]

I have a Metabo 3 speed cordless drill, with the highest speed being 3800 RPM, and love it. Definitely not cheaper than buying a pneumatic drill, but I always prefer cordless when possible.

Once you get used to drilling 1/8" holes with a 3800 RPM drill, using a 2000 RPM drill feels so slow. There is a real difference.

 

[Git]

When I built my Cobra Replica I bought two air powered drills - both where Chicago Pneumatic and I was very pleased with them. (One was a 90 degree drill for hard to get places)