Lawn mower rollers – restoration by  Jim Coombs

As web master I received an email asking if we could provide replacement rollers for an old ‘push’ lawnmower. As this seemed quite a simple task, I decided to respond to the request and received the following drawing.

The roller surface needed to be parallel to the central hole which had to run true. This was achieved as follows. 

I had some blocks of oak (traditionally the rollers would have been elm) as off-cuts from preparing my theme piece for the June competition. I selected three pieces; these were slightly larger in cross section than required, but being bigger they were easier to cut to exactly 90 mm deep on a band saw – so that was one dimension fixed. These were then drilled to produce the required central hole – second dimension fixed.

It would be possible, but laborious to mount these blocks between centres - for instance using a steb centre and a conventional live point, then turn with repeated checking using a suitable gauge. However, being in possession of a cup-shaped live centre,

I turned a spigot to fit this with a protruding end to exactly fit the central hole in the oak blocks.

The next step was to take another pre-drilled piece of oak and turn this to exactly 50 mm diameter and cut it off as a disc. This came out at 50.01mm as shown in the picture  – though I can’t be sure as the digital callipers I used indicated that they were ‘for non-professional use only’ so it is possible this was instrument error rather than mine!

This disc was then mounted on the live centre.

A piece of scrap wood was then turned to fit the 4-jaw chuck. This had a double spigot. The larger (inner) one was turned to 50 mm, and the smaller one turned as a jamb chuck to fit the hole in the workpiece.

The workpiece (drilled oak block) was then mounted on the jamb chuck spigot and held in place by the live centre spigot, with the 50 mm disc placed in line.This was then turned down to about 55 mm using a spindle roughing gouge ……

It was then finished off with a skew followed by 240, 320 and 400 grit so that the diameter matched that of the reference pieces at both ends.

It was then given a liberal coating of linseed oil.

Repeating the process resulted in the required end products as shown below.

Using this method, once set up, each was produced in a matter of minutes with no further measurement required during the turning process.