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Unisaw Restoration (June 2007)

I picked up an old (1959) unisaw as a sealed-bid auction item that was labeled "parts unisaw" with no additional information available.  When I went to take a look at it, I saw that it had an original goose egg motor cover, dust cover, both handwheels, all knobs, and a 1hp repulsion/induction (RI) motor that needed work.  It was missing the original switch plate, but included a replacement magnetic switch with low-voltage controller.  My bid won the item, so I gladly brought it home and set aside other projects to do my first major old 'arn restoration.  It was one of the most enjoyable projects I've ever done -- and I learned an immense amount about both how cabinet saws work and how to approach an old machine restoration project.  I hope you enjoy this photo essay.


First, some pictures of the saw in its original state, the first two at the auction site and the next few in my garage after arriving home.  All in all, it was in pretty good shape -- one of the advantages of being in California is that you often don't have to deal with severe rust.
unisawart1 unisawart2
unisawleft unisawright
unisawtable unisawtrunnions


The next step was to disassemble all of the parts, starting with external items such as handwheels, wiring, knobs, etc. (I didn't get any pics of those).
Then, I took out all of the internal "guts" of brackets, trunnions, worm gears, and arbor.
uniarboroldtop uniarboroldbottom
unifronttrunnion unireartrunnion
unigearsbottom unigutsold
unipulleyold uniyokeold


Here are those same pieces a couple days later after cleaning, then another week later after painting.
unigutsclean unigutspainted
uniyokeclean uniyokepainted


Before tackling any of the restoration work on my end, the most important question was whether the RI motor could be rebuilt.  Had it not been usable, I probably would have ended up parting out the saw rather than doing a complete restoration.  To say I was happy that it came back successfully would be a huge understatement.  It is such a sweet motor.  These are before and after photos.
unisawRImotor UniRImotor
uniRImotortag Here's the goose egg motor cover, after painting, that will go with the motor. unigooseeggpainted


Without question, the cabinet took the most time and effort in the entire restoration project.  Although it had essentially no rust, the cabinet had three coats of paint on top of the original Delta grey:  blue, brown, and finally white.  I used half a gallon of Jasco paint stripper over a weekend stripping it back to steel where possible, and to Delta grey at a minimum.

In addition to the coats of paint, the cabinet was riddled with more than 20 various holes from bolts, accessories, screws, you name it; it looked like a prop out of Bonnie and Clyde.  I patched the holes by patching the internal sides of the cabinet using a combination of metal mesh and bondo to provide a solid backer, then filled from the outside using solder and sanding flush.  I'm not sure how durable it will be, but since I don't weld, it was the best I could come up with after several other attempted methods failed miserably.  

This process of stripping, patching, priming and painting was so substantial, my wife and I documented it extensively.  The entire process has its own photo essay at this

cabinet restoration photos link

Here are a sampling of the photos.
unicabinet1 unicabinet8
unicabinet16 unicabinet18
unicabinet19 unicabinet25


Next up after the cabinet was the redoing the electrical.  The motor came back from the motor shop just as I was finishing the cabinet, so the timing was perfect.  The saw as acquired included a Furnas magnetic switch with low-voltage controller and remote start/stop switch.  In the original configuration, everything was packaged into a large box bolted onto the front of the cabinet.  I wanted to reuse the Furnas components if possible, but with the controller (transformer, contactor, and overload relay) installed on the back of the cabinet and the switch split off to the front.  Everything came out very well, with bench testing of the setup first, then reconnecting to install for use.
furnaswiring furnascontrolon
furnascontroller1 uniswitchinstalled


Getting close to finished, as we start cleaning/restoring the various badges, tags, accessories and other exterior components.  After stripping and repainting the handwheels, I forgot to take a pic of them finished, doh!!  The table took about five rounds of WD40, scotch-brite pads, and random-orbit sander.  I was particularly pleased with my first attempt at restoring the main serial number badge that had been in terrible condition under three coats of paint.
handwheelold handwheelnew
handwheelsboth dustcovertag
unitableold unitablenew
unibadgeold unibadgenew


Finally, assembly, test, and installation.  I still have two items that I'll live with for awhile:  looking for a switch plate to cover the hole where the original switch was located, and dust control.  I left the 2 1/2" dust port that somebody sometime cut in the cabinet and I'll eventually decide how to modify it for my garage DC setup.
unigutsassembled uniassembledbadge
uniassembled1 uniassembled2
uniassembled3 uniassembled4
uniassembled5 uniassembled6
uniassembledtop
First test cut
firsttestcut

And the grand finale:  installed, reassembled with the extension table and outfeed table, and set in place!!
unifinal1 unifinal2


Total time to complete the restoration was about one month, working nights and weekends, less one three-day weekend in the middle when we went camping.  It was an absolutely fascinating project and has certainly hooked me on looking to do more old machinery restorations in the future.  Thanks for looking and feel free to shoot me an email if you wish -- I have more pictures of a number of different aspects.

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