How to Make a Handle part 4 – Drilling The Holes

Marking the hole positions

Note: If you are making a new handle for the Spear and Jackson 9500R read the following:

This is the time to put the saw blade on top of the handle and mark precisely where the holes need to be drilled. The design has these points marked on it, but they might vary slightly in position for your saw blade.

If you are making your own saw, you can do this the other way around and first drill the holes in the handle in a position where they look pleasing to the eye. Then proceed to mark the location of the holes onto the blade when it is positioned in the slot of the handle.

Drilling the Holes for the Nuts and Bolts

How to approach drilling the holes depends on what nuts and bolts you will use for your saw. There are a few places online where you can buy them, you could make some yourself on the lathe, or you can reuse nuts and bolts from an old saw.

These have all slightly different complexities. On the top row are some turned bolts and nuts, and on the bottom row from left to right: a bought Thomas Flinn set, a used steel set, and three similar nuts and bolts, Spear and Jackson 1/2″ , Disston 1/2″, and Disston large 9/16″.
Simple bolts and nuts with a head that sits above the hole. This type is the easiest to fit. It usually has one diameter to drill for the shank, one to countersink/bore for the thicker part of the nut, and one square mortise. Not the easiest to make but very good to reuse from an old saw.
These sunken flush bolts and nuts have one diameter for the shank, usually one more diameter for the thicker part of the nut, and sometimes a square mortise. Very sturdy and nice looking, not as easy to make or fit as others.
This is the most simple split nut and bolt to turn on the lathe, and comparatively simple to fit. There is one diameter for the head and one for the shank and it’s kept in place by friction so the hole for the head needs to be a snug fit.
A Thomas Flinn nut and bolt. Very economical to buy but more complex to drill the holes for. There is one diameter for the head, one diameter for the shank and two more diameters for the thicker part of the nut and bolt.
These Disston nuts and bolts are very good to reuse, but a little more complex to drill. One diameter for the heads, one for the thicker part of the nut, and one for the shank plus a square mortise. The Spear and Jackson nuts and bolts are much the same.

When it comes to drilling holes, there are some general strategies that will help to get fitting holes for the nuts and bolts you will use. 

What to Aim for when Drilling the Holes

A.To be able to fit the nuts and bolts properly and flush with the side of the handle, the center of the hole needs to be in the same place on both sides of the handle. A good way to achieve this is to first make sure the two sides of the handle are indeed parallel. Secondly to use a drill press or any drill guide that makes sure a (pilot) drill goes in at right angles to the surface.

As a pilot a wood drill bit with brad point will help avoid wandering during the drilling. Keeping the length of the drill bit extending from the chuck short will also help if you are using a thin drill.

Alternatively, it is also an option to use split nuts with oversize bolt heads and sand or file them flush after installation. This is the historical way split nuts were installed on saws and this needs much less accuracy.

Antique splits nuts that were sanded flush to the side of the handle

B. The parts of the holes need to be fairly concentric when there are stepped diameters for the head and the shank. Most of this is achievable by planning the order of different drills to use. When the head of the bolt and part of the nut need counterbores, you can ensure concentricity by first using a pilot drill.

Pilot and two counterbores

When using Forstner bits and Brad point drills, a small pilot hole that accommodates multiple size drills can be helpful. The sequence of drills could be; 1,5mm pilot hole, head diameter Forstner drill, thicker part of the nut diameter, shank diameter Brad point drill.

Pilot, Forstner bit, Brad point drill bits.

Alternatively it also works to use the small 2mm drill after the Forstner and big Brad point to get to the other side of the handle.

C. The hole for the shank of the bolt needs to be slightly oversize for the bolt to go in easily. A little filing with a round file or a tapered reamer will make it easier for the shank of the bolt to go through.

5 to 6 mm reamer and 5 mm round file

D. The sunken parts which fit the heads need to be drilled to the right depth. With the drill press it’s possible to use its depth stop to drill to the right depth for the heads of the nuts and bolts to end up flush with the surface. Drill a hole on a test piece or cut off from the handle blank with the same thickness to set the depth on the drill press.

It’s possible to make depth stops from scrap wood and drill collars if you have a drill press (or have a friend who has one) after which you can use the depth stop itself to drill at right angles with a hand drill.

Forstner bit depth stops
Countersink depth stop
Brad point bit depth stops
TCT Countersink depth stop seen from underside. Lots of clearance for chips needed.

It’s also possible to drill to depth by eye and use calipers to measure the depth. a mark on the drill bit at the right depth can help. There is one catch (!) its easy to mar the edge of the hole if you have to reinsert the drill bit to drill deeper. On the other hand, a hole that is too deep can be filled with some sawdust to bring it to the right depth.

E. Many bolts have a square part right under the head to stop them from spinning in the hole. A square part will often need to be cut with a small width chisel to accommodate a good fit.

Square mortise

The Sequence of Drilling

5 nut and bolt styles
Drill the Brad point for the shank so the very tip comes out on the other side only. This gives enough support for the Forstner on the other side to be concentric.
Altenative drilling with TCT and HSS counterbores: 4mm Brad point – 12.7 mm TCT counterbore – m4 counterbore – 12.7 mm TCT counterbore – 5mm tapered reamer.