When the bench was put together and used a little, I saw that a Moxon-style screwdriver on the left would be a useful addition.
Moxon or Twin Screws are described in Mechanick Exercises by Joseph Moxon. He does not claim to have invented it and mentions it as one of the usual hold / squeeze methods. In the 19th century, the use of threaded rods / nuts increased due to a more precise knife machining process, but screw threads had existed since before the 300s BC. it seems unlikely that this style of bench clamp has existed for a long time.
The screw is as simple as it gets, a length of threaded rod and nuts are used to compress two chops with work piece in between.
Cost ~ £ 24 for purchases
But I didn't use all the nuts and washers so it can be said to cost £ 1
- Wood for the chops – I used 47mm x 255mm beam that remained from the bench building.
- Something for the handles
- 20mm Forsner piece
- 20 mm (or adjustable) key
First I mark and drill 20 mm holes in the chop and the workbench's front apron, the depth is set to 100 mm worktop plus space for a nut and a key. I cut a cutout for a nut on the front of the apron to lock the threaded bar on the bench, for me it is> 15 mm deep, I go a few mm deeper than my M20 nuts. I secure the threaded rod and leave a useful amount sticking out.
The plate on Moxon's screw shows the handles and the threaded rod, so that you turn the handles twist the rod and move the chop. This is relatively easy to do if you make your own screw thread and leave a lump of wood at one end. However, it is a little more difficult to fix a handle on zinc-coated steel (it is damp in the shed), so on many modern cheap loads (like this one) the threaded rod is fixed as the nuts move up and down to compress the chopping. This is the back of my shed so I probably won't go over and catch at the end of the bar, although they won't be in maximum extension for the most part.
Measure the same hole on the front notch and check it against the threaded rod before drilling. Then put a few nuts and washers on the front and it's done except for the handles.
I've seen many people make wooden or metal handles, I haven't seen any 3D printed yet … maybe for good reason? I can see how force against the nut would blow out a plastic handle so I will rediscover mine with metal from an aerosol can – this is designed to withstand an internal force so it can help.