Metalwork - Projects - Adjustable Spanner

This is a handy little tool but it is difficult to make well. It can be used both as an Adjustable Spanner, as intended, and as a workholding device.

Cutting out the 'slot' in the body is time consuming. Use a Ø7mm drill in the wider sections and a Ø5mm drill in the narrow sections. Then using a junior hacksaw cut between the drilled holes. This will remove the majority of the material. Accuracy is needed when drilling, especially in the narrow sections.

Here, the Adjustable Jaw is manufactured from one piece of steel. You would really need to use a 4 Jaw Chuck to create the M6 screw section. Trying to file this is impractical, (although not impossible). As an alternative it could be manufactured from two pieces of steel by making the block section and the screw section from two pieces of steel. Drill and tap M5, the centre of the block section side. On the lathe, turn down the unthreaded end of the screw section and thread M5. Screw the two pieces together and braze so that they won't come apart. (Note : Consider if you will heat treat this piece before brazing.)

The plans makes use of 2 Holding Plates. These are there to stop the Adjustable Jaw from falling out of the body. Only one is required if you are not going to be turning the Adjustable Spanner over. The screws holding the Holding Plates to the Adjustable Jaw are 6.5mm in length to ensure the Holding Plates are not tight against the body, thus restricting movement.

You may want to consider Heat Treating the tool parts after manufacture to improve it's life expectancy. Unless you make it from a higher carbon content steel than the suggested mild steel, you're only real option is to Case Harden the parts. I will be making a page about Heat Treatment of Steel soon and will provide a link here when it's done.

Parts List

Part No. Part Name Required Material & Description
1 Body 1 Mild Steel
2 Adjustable Jaw 1 Mild Steel
3 Holding Plate 2 Mild Steel
4 Thumb Nut 1 Mild Steel

As Supplied

Part No. Part Name Required Material and Description
5 M3 x 6.5 Pan Head Set Screw 8 Steel

Zip Files

Download All : Solidworks Part, Solidworks Drawing, PDF of Drawing. 3D images.

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