Drilling (under construction)

Drilling is an often needed job in model locomotive construction. Next to soldering it is the most common skill to master. Is there much to be said about drilling then? Yes and no. No, in the sense that the principles are simple. Yes, because there is much to think of. Drilling is essentially very simple: hold a drill to an object, turn it and the drill eats away material. That's it, thank you for reading this page.

You're probably not here because it was that simple. You must have broken many drills by now, many of them stuck awkwardly and obtrusively in the newly drilled hole, or found your hole way off the intended spot. So you are here because you found out that drilling is not that simple.

The photo above demonstrates the very truth of Murphy's Laws of model railroading

• if your drill can get stuck it will at the worst possible moment
• if it gets stuck, it will break
• if it breaks it will leave an unremovable piece of the hardest steel in your precious boiler

and most of all

• it was your last drill of that particular size.

Principles

There are a few rules that you must obey:

• Don't bend the drill, it will inevitably break.
• Keep your drill clean. Don't try to drill the hole in one go. Especially with small drill bits the chips tend to clog the hole and get stuck between the drill shaft and the material you are drilling. Either heat starts building up or the drill suddenly gets stuck and breaks. Do it gently. Drive the drill in then pull it back, drilling the holes in several stages.
• Adjust the speed. There are many rules about this but my motto is: take your time. In general small drills need more revs than larger ones because what counts is not so much the number of revs but the speed of the circumference of the drill. In doubt: rev it up. More drill got stuck and broke because of slow speed than drills got overheated and burnt
• Add oil! Adding cutting or drilling oil keeps the friction of the drill down.

Accuracy

Personally I don't believe I could drill accurately from hand. It seems other modellers do. I can't. There is no doubt in my mind that cannot achieve the accuracy shown below, a 0.5mm drill in less than 1.0 mm brass, without aid So I bought a drill stand that holds my drill vertically and goes up and down in a straight line. To help positioning my workpiece the drill stand has been fitted with a cross table and a vise. The  cross table also sports a simple vise which can easily be removed if need be.

Next to my airbrush equipment this was my most expensive piece of tooling (by 2013) but it paid back a hundred times! It has some setbacks which I cannot overlook. The crosstable give an measurable and predictable accuracy in both horizontal planes but the vertical plane is only controlled by the drill stand level without any kind of depth measuring. So drilling vertical is much of a guess. Second, the mechanism of the drill stand allows for a little play if do not exert vertical pressure on the lever. This impedes you accuracy. Knowing that you can achieve excellent results.

Oil

I already mentioned it in the principles: add oil. Advise on this subject is contradictory so try it for yourself and see if I'm right.

In my humble opinion it has too many advantages to ignore.

• It greases the shaft of the drill hole and prevents the shaft of the drill getting stuck
• It cools the drill tip that little bit
• As a bonus the little droplet of oil on the outside of the drill keeps the little drill shards from flying away.

There is specialized drill oil. Undoubtedly it is the best in its class, but I have not been able to source it in a reasonable packaging quantity. I mean, 5 litres will cost me a lot and lasts 500 modeller's lifetimes. So 100ml or so will do but have not found it yet. So for the time being I make do with the very thin oil I use to oil my locomotives. Any oil is better than none at all and the thinner the better. Its container has a needle-like applicator which works just fine to deposit a smallest of droplets on the drill spot.

Rinse the part you have drilled with a small brush and bit of turpentine of white spirit