mvigod

I have some heavy duty landing gear made by TNT on my GiantScaleAirplanes Extra. I need to drill a few holes in each side to secure some new wheel pants. Now bear with me cuz I don't drill too much metal. Here are the questions...

Do I have to take the gear off and put on a drill press or is it ok to drill it out right on the plane?

Should I begin with the bit size I actually need or start with smaller bits (need to drill for a 6-32 screw to go through)?

The gear itself is thick...I think 1/4"...should I put any kind of oil or something on the bit while drilling? Seem to recall this is advisable.

Any other tips or caveats for drilling out these holes...let's hear 'em cause RCadmin doesn't want to ruin this custom landing gear with any of his drilling equipment...

Any particular speed to drill this stuff at? I have a regular var speed electric and cordless var speed drill. Also have drill press (never used yet!)

thanks.

Ed Smith

Even drilling aluminum requires a fair bit of pressure. Drilling by hand with a an electric drill means you will have to hold the airplane steady while you drill. You will probably end up with an out of square and oversize hole. Do it by hand as a last resort.

If you can do it on your drill press then do so. Markout out where to want the hole to be. Centre punch the hole position, this gives a 'dent' for the drill bit to pick up and not slide across the metal. If you do not have a centre punch grind a point on a short piece of 1/8 music wire. Drill the hole the finished size you want. If opening up holes on some of the softer metals the drill bit sometimes bites and breaks or chews up the hole. It is not likely you will have the correct cutting fluid for aluminum in your workshop. Some alternatives, lighter fluid, light machine oil or if nothing is available spit on it (Apologies to all the Machinists out there). For the size of hole you are drilling, on a hobby type drill press, the middle of the speed range would be my suggestion.

Ed S

Jazzy

If you're fairly adept with your hand tools don't be afraid to use them. Center punching the exact spot does indeed ensure proper placement of the hole. If you don't want to remove the gear from the fuse use a 1/16" bit for a pilot hole. It is not necessary to drill all of the way through with the smaller bit - up to an eighth inch would be fine. The size bit necessary to 'slip' a 6-32 through would be a 9/64".
Because aluminum is a soft metal, (even tempered AL is not all that hard), a relatively slow-mid range speed with a fair amount of constant pressure will yield the best results. (Just don't use a lot of pressure on that 1/16" bit. Chances are you'll exert a side force while drilling and snap the bit.)
If you use too high an RPM the bit won't bite the softer metal well and will build up a lot of heat.
Cutting fluid should not be necessary for that small of a hole in that thin of AL.

Hope all works well!

Jeff

Steve Collins

My Feedback: (8)

In my experience it is always best to use some kind of lubricant on the bit. I have used 3-in-one oil, marvel air tool oil, after-run oil, just about any kind of lubricant that is handy. Sure, the proper cutting oil would be best but most of us non-machinist modelers don't even know what that is. Follow the previous advice about the slow drilling speeds.

BigBird1

My Feedback: (4)

I had a little laugh over this one....
Really I don't mean to cut anyone down, bear with me please..
I am a machinest and welder
Lighter fluid is naphtna..used in lighters (Ala Zippo) and should stay in lighters not used for lubricant unless ya want to light a smoke while drilling the hole..
Some oils will stain the aluminum if gotten too hot while drilling...
Leaving the landing gear in the plane can be done if their is a backup block behind the gear that is being drilled or you just hang the drill bit and have a spinning plane or worse..doing major damage to landing gear blocks etc....center punching is a must or drill will usually "walk" and not be where you want the hole...."step drilling" is very good idea, but as you drill the hole bigger with each drill you also run the risk of the drill hanging in the previous drilled out hold...a drill is like a screw and will actually screw itself into something soft like aluminum (ala Verrrrry big ugly hole now)
The best thing to do is to take off the landing gear, put it in a vise and then drill it with a drill press if you have one or very carefuly with a hand drill and light pressure with a spot of kerosene..or light machiene oil and have a block of hard wood behind it...start with a 1/16 and work up using 2 to 3 sizes bigger bit each time not the next size up..or the flutes (machinest talk) will hang and either give you a good sprained wrist or jerk the piece out of your hand...off the table etc....

Just 2 cents worth

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I never met a Chaos I didn't like....

Ed Smith

Bigbird wrote

>>I had a little laugh over this one....
Really I don't mean to cut anyone down, bear with me please..
I am a machinest and welder
Lighter fluid is naphtna..used in lighters (Ala Zippo) and should stay in lighters not used for lubricant unless ya want to light a smoke while drilling the hole..

BigBird1

My Feedback: (4)

I'll except that...but what an expensive lighter....