Technically these are 10-20-40 and 20-40-80 Blocks and Arc Euro Trade calls them Stevenson’s Blocks, others call them 1 2 3 Blocks. Whatever the name these are really useful to support items on the milling table.
Review
Great for jacking up workpieces, aligning workpieces on a milling table or using as a measuring aid.
Toughened and precision ground steel packing blocks with 8 TAPPED and 8 CLEARANCE holes. Thus allowing two or more blocks to be connected together in various configurations such as angle blocks, tee blocks, or used as a fixture to hold small parts for machining.
The smaller pair are 10x20x40mm with 6mm tapped threads and clearance holes.
The larger pair are 20x40x80mm with 8mm tapped threads and clearance holes.
I checked the dimensions with a digital caliper between the large and small blocks and they are the same within the tolerance of the caliper (0.01mm).
One thing I have noticed is that the surface does attract slight rusting more than the other tools in my workshop. Hence I would recommend wrapping them up in an oiled paper to keep them safer and sparkling for longer.
Price: approx £12 and £18 for these sets.
The photograph to the right shows me using the larger set of blocks to support the edge of a part that I was fly-cutting. This is the open crankcase for the transitional engine.
This is probably not the most obvious use for these blocks. Any large block that had been machined square would have done the same job. Sometimes that is the point, you don’t have a large block of material machined square laying around. If you did have something spare you would have probably machined it into something else when desperate for material.
The image to the left shows the view from above.
The part being machined was bolted to an angle plate and the Stevenson blocks were held on the table using a clamping set. The blocks themselves had been held together with caphead bolts.
Conclusion
Accurate, nicely machined. A useful aid when setting items up on a table. Adding support to parts or just to lift something to the correct height.
Available at arceurotrade.co.uk
There are a number of different ways to hold or clamp a workpiece – see our page on workholding.
Transitional Engine
This model engine was designed to look like an engine from the late 19th century that had been converted from steam to internal combustion.