Drilling holes with crisp edges in wood

[laps]

Hi All,

When drilling larger diameters holes in the hull of model ships for portholes, masts etc. it can be a challenge to get a nice clean hole without damaging the wooden edges. Also the drill can wander off-center if the material underneath consists of different materials, for example plywood and balsa below the same hole. 

It is possible to start with a smaller diameter drill and then enlarge the hole with bigger drills or files. Drills for making holes in metal is to me a no-go in wood as they tend to wander off-center, especially in woods like pine. Drills specially designed for drilling holes in wood should be used. They usually have a point to ensure that the hole is drilled where it is supposed to be. Also, the circumference has sharp cutting edges (spurs); the purpose of these is to cut the wood fibers and secure a sharp edge. There are a lot of different manufacturers of brad-point drill bits for wood; they can all cut a hole but the quality of the hole varies a lot. As with a lot of things - the more you pay the better quality hole you get. 

 

So I thought I would share my preferred go-to brand of brad-point twist drills: https://www.fine-tools.com/holzspiralbohrer.html

The spurs are very sharp and leaves a nice clean edge in any wood I have tried. The smallest diameter with spurs is 2 mm all the way up to 20 mm. 

 

As you can see, they are a bit pricey but they will last a life time for any modeler. If you are worried about the longevity, you can also get these drills with tungsten-carbide bits from 3 mm. 

 

/Lars Peter

 

 

  

[Gregory]

At the risk of sounding negative, how often do you really need a "crisp" hole that is not going to be covered by some type of framing, such as mast partners or other framing.

At the least, any round hole would probably need some kind of beveling

[wefalck]

It is also good practice to clamp a piece of waste wood over the hole to be drilled, or a metal plate with a hole pre-drilled to the correct diameter. This prevents the drill from wandering and ripping out pieces on entry.

[BobG]

I usually use a small center punch or a pointed tool to make a small, pointed dent in the wood at the exact center of the hole and then drill a pilot hole with a very small drill bit. The pilot hole centers and guides the drill bit used to make the finished hole. I use this method for tiny holes drilled with a pin vise and larger holes drilled with power. 

 

Bob

[Moab]

I place a piece of wood under the piece to be drilled. Keep it tight to the piece. Works great...Moab

[Roger Pellett]

Brass tubing is the modelmakers friend.  Short pieces can be used to line drilled holes to produce a clean sharp edge where required.  It can also be used to make a miniature hole saw for cutting sharp edged holes in wood.

 

Roger

[Bob Blarney]

Occasionally, I have applied a wash coat of shellac to lock the surface fibers down.  The shellac can be sanded off easily or wiped off with alcohol.   As always, first try this on a piece of scrap of the same species.

[Richard in Missouri]

I have been happy with the Fisch brad point bits. This is another premium bit. As previously mentioned having a scrap board on the waste side helps and if you have a drill press it can help.