I've finally started work on my Stormraven (squeee!), and that bad boy has a whopping 30 barrels to drill out if you magnetize for all the options. Figured this was as good a time as any to show how I do this. This is going to sound like a lot of steps, but it happens organically and quickly. The whole thing took me 5 minutes including taking pictures.
What you'll need:
- Sandpaper- I recommend nail files so you can hold a solid flat surface in your hand. Get one of those that has two grits on the finer end of things from your local drug store, or steal it from some lady in your house.
- Hobby knife- with fresh blades! I'm going to call it an Xacto, because 'Merica.
- Pin Vise- You can get them at many hobby stores, swap meet tool guys, some better equipped hardware stores, online. If you can get your hands on it before hand, test out the threads. There are a lot of crappy Chinese tools out there that feel like metal grinding on ass when you try to twist the chuck collar. It'll still work, but not as well as you'd like. My favorite new pin vise is a kit I bought in a hobby store on my trip to Hong Kong. It's well greased, and comes with 4 collets of different sizes (that's the 4-jawed part inside the chuck sleeve that holds the bit), and several hobby-appropriate sized bits. Some vices out there even come with a full 3 jaw chuck like the front of your power drill, but I don't recommend that for hobby purposes. They get really wide and make it difficult to get in to the small areas that are so common on our models.
- Drill Bits- new sharp ones will save you a lot of headaches. A crappy old dull bit will be more likely to catch on the sides of your perfectly drilled hole and muck it all up. Save yourself the headache.
Next, take your (sharp!) Xacto knife and give yourself an approximate starter hole. Just poke it in there gently. Take it out. Look at it. Is it centered? No? THEN DON'T FREAKING DRILL! Fix it. If you don't press too hard to start, you can re-center it.
Once you're happy with your center hole, put your blade back in, press just a touch harder and spin it around a couple of times. If you're not 100% satisfied with your starting hole, you can also push sideways a little bit here to get yourself centered. You're not digging a hole here, just making the triangular hole from the blade into a roughly round shape. Keep it small. You don't want to press too hard because A) you can break off the blade tip which makes it really hard to poke an accurate hole, plus leaves a sharp metal chunk inside your model, and B) an Xacto blade isn't designed to cut sideways- we're intentionally misusing the tool to grind the side of the hole off a little bit to reshape it. Pressing too hard can give you a jagged outside to the hole that just gives the drill bit little edges to grab on to.
You've now got a round pilot hole. Take a small bit in your pin vice (maybe 0.04"/0.1mm) and round it out further. Again, if you're not happy with your centering, you can push to one side a little as you do this. That's your last chance to do it easily though.
Now gently but firmly drill out a hole to your target depth. This bit may be half the size of your final hole- you just want to establish depth here. The important thing here is to let the bit do the work. Pressing like hell can only push you sideways and undo all the centering you just did. If you have to press hard, your bit is dull. Proceed at your own risk. You really don't have to go all that deep either. 1/8" is plenty for most small arms.
Once this hole is done, you can move up in bit size slowly until you reach your target width. If my final hole is 1/8" (3.175mm), I might use 3-4 bits to get there depending on the outside diameter of the barrel. You want to shave off the sides slowly. If you go too big too quickly, or start with your final size, it's really easy to pull sideways and botch the whole thing. Bigger bits also mean you're moving big chunks of drilled-out plastic around inside a thin barrel and the pressure can warp the outside of the barrel. Go slow.
Another important pointer: When in doubt, go backwards. Often as we move up in sizes, the top of the hole can get a little jagged- we're talking microscopic here, but to a drill bit it matters. It's always a safe bet to lightly spin the new bit backwards a couple of turns to soften up the edge of the hole before you start drilling in. If at any point you feel the bit catching, stop and back it out and clean the hole up before proceeding.
Once you've hit your final size, you can consider yourself done if you like. You'll probably have a very thin edge of weird plastic right at the tip of the hole. If you don't trust your knife skills, just stop and pat yourself on the back for having drilled barrels. If you fancy a challenge, you can try to soften that up with your hobby knife or with gentle sanding.
That's it. For some, this won't be earth shattering, but hopefully others will find it useful. I want to see drilled barrels out there, kids! Now go out there and be somebody. By putting holes in things.