Imagine my delight when I discovered this new tips video from Chris at Clickspring, the first in a series of engineering tips videos he now plans. Chris’ work and his videos are always inspiring and informative, and this one is no different. In it, he outlines 8 of his top tips for metal hand filing.
#1 Use Only the Best-Quality Files
The difference in durability and cut-quality is dramatic. Chris recommends Swiss-made Grobet files.
#2 Create Safe Surfaces/Edge(s)
So that your file only cuts one surface at a time, Chris recommends blunting at least one side on your files. Isolating the cutting to a single surface makes your cutting profile that much easier to control. Grinding a safe surface also has the added benefit of creating a nice sharp line along the edges of your file so that you can get cleanly into corners.
#3 The Corners are Key
First, when cutting away bulk material prior to filing, you want to leave some metal to work with. You then want to identify the critical corners (the locations that must be perfect) of your workpiece and start your file cuts working directly toward those. Leave some material short of your target profile and switch to finer files to establish the final profile as you close in on the line of the profile.
#4 Correct Mistakes Early
Keep checking your work often, and if you see a mistake developing, correct it as soon as possible before things get away from you.
#5 Create a Cross-Grain to Check for Errors
Prior to your cut, establish a cross-grain pattern on the workpiece so that you can see what’s happening to it as the metal is being removed. You can direct a light onto the piece to see this pattern more clearly.
#6 Use Reference Edges to Align Your Work
As you file, pay attention to the orientation of your file in relation to reference edges around you like the edges of your work holder, your bench, etc. Constantly using this reference for visual feedback will help you keep your file properly oriented.
#7 Use Draw Filing for the Best Square Edges
One way to limit human error in filing is to limit movement to that which has less inclination to drift. Draw filing is a great option here. The length of the workpiece itself becomes a useful reference edge. It’s also a great technique for establishing the same profile across two workpieces at the same time.
#8 Use Filing Buttons and Guides for Complex Shapes
It can be hard to freehand-file complex and curving shapes. Filing buttons and filing guides give you good reference and visual feedback as you work.