Restoration of a 1963 Snap-on KRA-300B
Published: 2015-07-03
In late 2014, I found a 1963 Snap-on KRA-300B rollcab listed on Craigslist for a good price. It had a few minor dents and a budget repaint, but all of the drawers were intact and mostly undamaged. Because this was an early KRA-300, the front lip of each drawer was fitted with chromed steel accents, riveted in place. Most importantly, the aluminum tambour door fitted to this box was still in good condition.
I decided to do a full restoration of the box, and the biggest issue was the fact that the chrome accent strips were only in fair condition (at best), and one of them was missing. After taking careful measurements of one of the trim pieces, I made a drawing using LibreCAD and had Big Blue Saw cut the pattern with waterjet from 5052 aluminum at 0.025" thickness. I ordered 50 units and they cost about $2.10/ea. I then spent some time dressing the edges on a wheel to clean up the burrs. I polished the raw aluminum using Simichrome and a felt polishing tool in a Foredom SR flex shaft motor. To shape the pieces, I made a die by cutting a length of 0.625" ID / 1.000" OD steel tube lengthwise to create a half-round channel, and matching it to a length of 19/32" rod stock. I then sandwiched each aluminum piece between the two and hammered it to take the shape. During reassembly later on, I attached each one to a drawer with 3/32" blind rivets.
Here's the .dxf CAD file that I created (in case anyone wants to make their own), and here's a photo of the trim pieces in different stages of production (dressed, polished, and formed):
I completely disassembled the box and had it and all of its drawers powder coated with TIGER Coatings "Bengal Red". Note that this isn't an exact match for the original color: it's slightly darker and has less yellow in it.
The original Snap-on badge was missing when I got the box, so I got a replacement on eBay. Although I did get the original lock assembly, it came with no keys (shocking!) so I decided to simply replace the lock. The Snap-on 823037 fits fine; I just had to supply my own hardware. The panel nut that threads onto the back is 3/4"–24 and the tapped hole is screw size 12–24, about 5/16" deep. The mounting pattern for the casters is 2 7/8" x 1 3/4", and I replaced these as well (with units from McMaster-Carr) because the originals were shedding ball bearings and were pretty much used up.
The tambour door, as I mentioned above, was in pretty good shape. A couple minor dings, but much better than many that I've seen on other boxes. I suspect this one was rolled up into the box most of the time, and escaped the sort of damage that it would otherwise get with heavy shop use. I disassembled and thoroughly cleaned the door -- each aluminum slat can be freed from its neighbors by sliding it out laterally.
In keeping with this KRA-300 having seen a lot of use, about half of its drawer slides were damaged. Fortunately, Snap-on still produces equivalent parts. The original small and large slides had the part numbers 8-2147 and 8-753, respectively. These have been replaced in modern Snap-on stock by 8-1957 and 8-767, and they're relatively inexpensive -- less than $10/ea, even for the big ones. Unfortunately, the superseding slides seem to be slightly different, dimensionally; they're thicker than the originals, and this makes the drawer action stiffer. A couple of my drawers are now so tight that they're almost unusable. I haven't yet found a solution to this problem.