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How to use a hammer and dolly for metal shaping

By Chad Atkinson - Story & Photos, 03 Aug 2019 DIY

How to use a hammer and dolly for metal shaping

An overview of metal-finishing with our resident metal maestro, Chad Atkinson

THE most primitive aspect of metal-shaping would have to be the hammer-and-dolly work. Here is a guide on how to use a hammer and dolly to knock a panel into shape and then fine-tune it.

STEP-BY-STEP:

metal finishingStep 1. Just about any solid object can be utilised as a dolly, which is, in basic terms, a hand-held anvil. The key is to use an object whose contour matches the back side of the panel you are working on. Yes, that is a tow-ball in the photo – it’s perfect for bringing out tiny low areas.

 

metal finishingStep 2. After choosing the correct hammer/slapper face for the application, remember it’s all in the wrist with these tools; if you’re swinging from the elbow thing are likely to get messy, with the exception of jobs such as skinning a panel. The faces of both tools must be kept in good order; any indentations or a build-up of crap will end up showing on your panel.

 

metal finishingStep 3. An adjustable metal-file with interchangeable files is a great bit of kit and can be adjusted to suit the panel’s contour. Other files such as speed files may also be of assistance.

 

metal finishingStep 4. With the basic rundown out of the way, it’s time to metal-finish a piece using hand tools. Things might look pretty good and ready to go here, but it’s difficult to tell. For the purpose of being able to show our progress in photographs, I have used some black guide coat. It’s not essential, but it can be helpful in getting the best result.

 

metal finishingStep 5. With a light metal-file we can now differentiate between the highs and lows. Highs don't necessarily mean that area is too high; it can also be showing areas that are the true face of the panel.

 

metal finishingStep 6. The correct dolly is chosen for the back of the piece. While holding the dolly to the back, a couple of small taps on the panel with the slapper will help locate the dolly so the tools are correctly aligned to one another.

 

metal finishingStep 7. I’m using a rough slapper, because the rough face will mark the metal and show you were you have been. A smooth slapper will work, but it’s more difficult to follow visually. As the name ‘slapper' suggests, a sideways slapping motion is most effective here. This will bring up the lows along with knocking down the highs to match the face of the dolly.

 

metal finishingStep 8. To check progress, another light metal-file tells the story. This process is repeated over and over again until things are dead straight. Using the planishing hammer in conjunction with this process helps finalise things. Working with 1mm sheet, it’s important to take your time with the hammer work. While knocking down the panel with the metal-file can look like the easier option, you don’t really want to remove too much material and end up with something that’s paper-thin.

 

metal finishingStep 9. Once happy with the file work, it’s time to move on to sanding out the scratches. This is basically a polishing process, with sanding going from 80-grit progressively up to 500-grit. A mudslinger with 80-grit is used first up. Letting the machine do its thing and being careful to not lean on it is the trick here. That large, flat face can generate a bit of heat, and potentially cause distortion.

 

metal finishingStep 10. Next up we switch to 80-grit on a random orbital sander, and things are starting to look good now. The 80 is swapped out for 180, 320, 500 and then hand-finished with a fine red Scotch-Brite. With the scratches now gone, there are still a few imperfections in the metal from the original shaping work. These can be removed by repeating this process, or by using tools such as a bullseye pick for the deeper ones.

 

metal finishingStep 11. In saying that, most of those little indiscretions will vanish during the primer stage. This is just how I did the job, but it’s important to keep in mind that there is nothing wrong with fillers, as long as they are used correctly.

 

metal finishingStep 12. To protect the bare metal from surface rust on larger, ongoing projects – or while other areas are being attended to – products like Oxytech’s Easy Phos can be applied.

 

metal finishingA solid afternoon’s work went into finishing the small section of the piece shown, so it’s not a quick process by any means. As always, there are various other techniques that will yield the same end result, but this is my preferred method.

Read next: How to use an English wheel for metal shaping

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