Saving steel: Incredible shrinking disc can save valuable old metal


Story and photos by ‘Rotten’ Rodney Bauman

For hobbyist restorers and rodders alike, key ingredients such as time, funds, place to work, etc., must all come together at the same time — and sometimes that takes years. Barry Waugaman of Anza, Calif., managed to secure his Deuce five-window in the mid ’70s, which was indeed a good time to buy a 1932 Ford. However, with child-raising and life in general in high gear, it just wasn’t ’til 2011 when the patient coupe would finally begin to receive attention. By that time, a tall Mesquite tree had grown through the car’s frame, so standard disassembly procedures commenced with a not-so-standard chain saw.

With invaluable assistance from friends Art Johnson, Mike Limerez and Dave Roach, Waugaman’s coupe was up and runnin’ for the 49th LA Roadster Show. Not too long afterward, while legally parked at a shopping center, the coupe was clobbered by a roll-away pickup truck, which marred its finish as it deeply creased its left door. Waugaman’s repair shop of choice was Hot Rods & Custom Stuff in Escondido, Calif. It could have gone differently, but after some negotiation, the other side’s insurance company finally allowed time to do the job right.

During the course of this insurance work collision repair, an ol’ dog learned a new trick. As an old panel pounder myself, I can wield a torch, a hammer, a dolly, a Vixen file and so on. Although I’ve never owned one, I’m also aware of shrinking discs. If you’ve attended a major show in recent years, you’ve likely seen them demonstrated — and likely been impressed, too. The earliest factory-made shrinking discs that I can recall were catching on in the late 1980s. The general concept itself, however, may date farther back.




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According to one grizzled guru of the auto body trade, a reversed (smooth side out) abrasive body disc will generate heat through friction without removing precious metal — thus creating an effective shrinking disc. Another has succeeded with a homemade disc of stainless steel, which could get one to thinking that the neighbor’s hubcap, or Fido’s bowl, or maybe even a lid from Mom’s Revere Ware, could be modified to function as a shrinking disc. But we don’t recommend y’all try that at home. Improper tool usage, and/or usage of improper tools, puts body parts at risk. Not just hoods and doors and so on, but arms and legs and so on, too.

So, with the safety warning portion of the story out of the way, shall we now refocus our attention to the repair job at hand? Who remembers Barry Waugaman’s smashed Deuce five-window? From here, you’re all invited in to watch as a crafty Hot Rods & Custom Stuff fabricator demonstrates use of the incredible shrinking disc.


1. The damaged door’s skin is badly stretched. While the used ’32 Ford door supply hasn’t run completely dry, surviving doors are rare and rather expensive, so hunting down a replacement seems impractical. A new door skin could be fabricated, however, and at this time, that’s one of two options on the proverbial table.




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2. HR&CS body ‘n’ paint department head Andy accepts challenges. As it worked out, the damaged door responded favorably. With the “rough-out” phase of the body work completed, the door is passed along to HR&CS’ multi-talented fabricator, Jeremy, for metal finishing.


3. After a little more paint removal, the door is secured to the gantry mill table where Jeremy takes readings with a length of welding rod. This gives a clear view of the skin’s true condition. Were it not for the large stretched-out hump, it could be considered close enough for filler — at some other shop, perhaps.




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4. Sneaking a drift through this factory-provided opening, Jeremy works one of several small low areas. This is followed with further hammer ‘n’ dolly work. With some juggling, the necessary shrinking could be accomplished with a torch, slapper and dolly, but certain backside areas would be difficult to reach. This is a job for a shrinking disc.


5. Stainless-steel shrinking discs come in a multitude of shapes and sizes. This older-model disc resembles others that we used to see at auto body trade shows and it features a protective, downturned outer edge.


6. Now here’s the most basic of basic no-frills, stainless-steel shrinking discs. It stands to reason that this design’s outer edge will sharpen with use — putting its operator in a particularly vulnerable position in the off-chance of a disc fracture.


7. With his old Milwaukee body grinder, Jeremy is working the high spots. In theory, low spots can be raised via hammer, and then shrunken down to meet surrounding metal with the disc. But that’s only part of the process.


8. Heating the high spots is followed by quenching with water. Some body men apply water via a wet rag or squirt bottle. In an effort to avoid any flash-rust-related issues, Jeremy chooses cool, clean, compressed air. Heat, quench, heat, quench — repeat as necessary.


9. What we’ve witnessed to this point has taken a while. With the door skin’s repair now close to finished with only minimal filler work remaining, we’re quite satisfied with the shrinking disc’s performance.


10. Having made good use of allowed metal-finishing time, this insurance collision repair job is once again passed back to the HR&CS paint department. While it’s not a dead-on match, the addition of green toner lends a believable weathered look to PPG’s Envirobase, EPW115 waterborne primer.


11. Best of all, this door (which is likely the car’s original) was saved — it fits and functions once again as it should. From here, Barry Waugaman’s lil’ Deuce five-window coupe will reassume its rightful position on the street. Let’s pretend it never happened.




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