The Inlay Experience

Making scratchstocks.

Several people had cut out their scratchstocks in advance. We then screwed them together taking acount of the screw locations in relation to the cutter. When they came to use them though, the cutter holding arm was far too long. The arms fouled the cramps used to hold the groundwork panel to the bench. That can be solved by using a low profile panel clamping system (MH still to write up), but there is a second problem in that the long arm can encourage movement away from 90 degrees to the line being cut. In other words the long leverage can introduce wiggle. So the overlong scratchstocks were cut down to 6inches.

The positioning of the screws is important. They need to be near the cutter but not right on top of the cutter. Mine works well with just two screws, one from the front and the other from the back. In each case they are sunk below the surface and the clearance hole is drilled full so that there really is clearance and the other side of the stock is pulled up tight. I used No12 screws two inches long and cut the ends off in order to get a decent thickness of thread to bite into the stock.

In use don’t have the cutter projecting too much. 2mm is probably deep enough for a first line.

Cross-grain grooving.

There was some difficulty forming the edges of the cross-grain lines. I think there could have been more use of specially sharpened cutting gauges and making the cutter of the scratch stock a more precise fit by each one being individually ground for each person's particular inlay width, but at this stage the day was just an introduction to the use of workshop made tools and cutters and the group had some way to go in terms of cutter tuning.

Filing the cutters to a V would also have helped as per Colin Eden-Eadon in F&C 136. Again this comes under cutter tuning which will have to be tackled on another day.

There is also the Steve Latta method and workshop made versions of his cutters will be made in the future.

For the time being the traditional method of using a knife and straight-edge to form the cross-grain line edges was used.


Line size and Cutting your own lines

I had cut some inlay lines on my small Record bandsaw and I then demonstrated how to use a stringline draw-plate to thickness the lines. At that point we had some discussion about the terms 'line' and 'square'. In a workshop the term stringline is used for both thin lines and thick lines. Thick lines are sometimes sold and indeed cut as square section inlay. Square section 'lines' are also used as arris inlays on edges. There is great potential for confusion, so the best thing is to check the cross-sectional measurements ie 1.5mm by 1.5mm or 1.5mm by 0.7mm; and that brings us to the subject of veneer thickness. In historic furniture, and that was how I was trained, veneer was between 1.2mm and 3mm thick, with lots of variations in-between. Nowadays shop-bought veneer is about 0.6mm thick. That means that most producers of 'lines' expect them to be laid into 0.6mm veneers. The result is that bought lines tend to be flat and very thin and difficult for beginners to use. This is why I prefer to buy square section or to cut my own. I'm sorry that wasn't clear in my preliminary notes.

M42 Blades from APT

I used a new M42 bandsaw blade from Axminster Power Tools to cut a 3mm strip from a board which had been planed all around so I knew that I would have two fair edges once I had made the second 3mm rip cut. If you use a zero clearance sub-table you reduce the risk of the line being unsupported and breaking as it is cut. You also reduce the risk of shards of hardwood going into the works, although they shouldn't cause any problem to the band-wheels or saw. The M42 blades are significantly more expensive than standard blades but I used one from Workshop Heaven for 5 months before I had to change it. Usually I have to change a blade every 3-4 weeks. M42 blades are really made for industrial use and have groups of alternate pitch teeth. They will cut through metal and therefore for restorers who use lots of reclaimed timber they are a godsend. But even if you are not a restorer they are worth trying for their accuracy and durability. One interesting fact is that for small thicknesses up to about 2" I have found that they rip and cross-cut with equal ease.

Pictures courtesy of Rob Stoakley