What are Shrinking Discs?

When using a Shrinking Disc, you are able to shrink overstretched areas and repair damaged sheet metal panels to a like new condition, making for a better quality, longer lasting finish with little or no body filler! The secret to them is they create the heat that is needed to shrink through friction. They produce better results and are much more controllable than shrinking with a torch or a solid tipped stud gun. Using a torch often results in warping and further damaging the panel. With the shrinking disc and its large surface area, it eliminates some of the guess work, especially when smoothing a lumpy panel by only touching the higher overstretched areas! The heat is also more concentrated on the higher peaks of the damage and tapers off to the lower areas, which results in a much greater accuracy of heat placement.

The more you use it, and the better you get, the less filler you have to spread and sand! It saves lots of time on sanding, keeps the shop cleaner from having less putty dust, and makes for a better quality, longer lasting finish with little or no body filler at all!

How is it used?

In normal conditions, you would roughly straighten the panel, tap the dents and low areas up with a hammer and dolly and then make a couple of passes with the shrinking disc, heating and cooling. Look over the panel to determine were more work is needed, and using a hammer and dolly, rearrange or tap up any remaining low spots followed by a few more passes with the disc. After completing several loops of this process, your panel will be smooth, and back to normal surface tension.

When using the shrinking disc after welding in a patch panel to arrive at an almost invisible seam, you should start by carefully grinding the bulk of the weld. While doing this, you want to minimizing excessive heat buildup and prevent thinning of the panel itself. Then the HAZ (Heat Affected Zone, the area that was discolored while welding) needs to be stretched by using a hammer and dolly (with slightly more contour than your panel), striking the hammer "On Dolly". This is required, because the welding process heat causes shrinking just like the shrinking disc does, although it happens in an unwanted and uncontrolled manner. After stretching the HAZ, it will be closer to the original profile, but still lumpy, uneven and possibly over stretched from the various hammer blows. Now is when the shrinking disc works its magic. By using the shrinking disc over this area, and blending around the edges if needed, it will only touch the higher overstretched areas as mentioned before, and shrink them down so the entire weld area is smooth, and has the same surface level. More details on using the discs included in the Instruction Manual.