Router
My dad gave me a router that he picked up an auction. It had some problems and he didn't have a use for it. I already have a nice router, but I could always find a use for a second one (either as a router in a dedicated setup or a motor for something else). The router had a cutting bit stuck in the collet and would occasional turn off for a second. It's a little scary when a router (without soft-start) kicks back on unexpectedly. I soaked the cutter and collet in WD-40 for a little while and they came loose with some taps from a hammer. There was a lot of rust, so I cleaned all that up and oiled the collet and spindle.
I disassembled the router so I could figure out the electrical problem. The wiring looked fine, so I figured the switch was the problem. It was covered in sawdust, so my first thought was that the dust got inside the switch and interrupted the contacts. The switch is labeled as 1HP at 120V and the router is labeled as 1-1/2HP, so that had me a little worried, even though the switch looked factory original. In addition to 1HP, the switch is also labeled as 16A at 120V and the router is labeled as 8A. I think the router's claim of 1-1/2HP is overly optimistic, so I put those worries out of my head. The switch was riveted together, but when I tried to drill the rivets out they just spun. I switched to a rotary tool with a diamond grinding bit to grind the rims of the rivets without them spinning. Once I got the switch open I could see it was filled with sawdust. The dust had mixed with the grease inside the switch and I knew that got between the contacts and caused of the interrupted power. There were no signs of arcing on the contacts, so I cleaned everything up and reassembled the switch with some small screws and nuts.
When I had the router apart, I checked the bearings. They seemed a little sloppy, so I decided to replace them. The front bearing slipped off (not a good sign), but the rear needed a puller. I don't have a gear puller, so I made a simple puller out of some bolts and a piece of flat bar. The bearings were non-standard sizes, so I had trouble finding replacements. Both were 1/2" thick, but the rear one was 30mm OD x 10mm ID and the front was 1.375" OD x 0.625" ID (or so I thought). It seemed odd to use one metric bearing and one inch, but they were both non-standard thicknesses, so I figured it was just a goofy design. The diameters of those bearings are standard sizes, but those standard bearings are both thinner than 1/2". I ordered the standard bearings and figured I would just make some spacer rings. The rings were just a matter of some simple lathe work. When I went to assemble the router, I discovered a problem with my measurements. The rear bearing pressed on fine (in a vise), but no amount of pressure would seat the front bearing. I measured the bearing and it was true to size, but when I measured the shaft, I found my mistake. When I measured before ordering, I used dial calipers calibrated in inches. I thought the measurements were exactly 1.375" and 0.625". When I remeasured with a micrometer, I realized they were 1.378" (35mm) and 0.630" (16mm) which is a standard metric bearing size. Since it took the US post office 2 weeks to deliver my bearings (they were only going from Illinois to Pennsylvania), I didn't want to wait for new bearings. I decided to chuck the armature in the lathe and polish the shaft down to the proper size. It only took a few minutes with sandpaper. Once I got that straightened out, the assembly was easy. The switch seems fine and the router runs without shutting down.
This router doesn't have a spindle lock like my other one. You need to use 2 wrenches: one to hold the spindle and the other on the collet nut. The spindle nut sat partially inside the router body, so there was only room for a wrench about 3/16" thick. My Craftsman wrench is about 5/16" thick. The spacer ring I made for the inner race raised the spindle nut slightly, but my wrenches still wouldn't fit. I decided to make a simple wrench out of 1/4" x 1-1/2" flat bar. I laid out the design with a scriber on top of Sharpie and used my band saw to cut the rough shape. I used the [newly fixed] belt sander to finalize the shape of the wrench, then used the mill to make sure the opening was square and fit the 13/16" nut.
Click the pictures for larger images.
I disassembled the router so I could figure out the electrical problem. The wiring looked fine, so I figured the switch was the problem. It was covered in sawdust, so my first thought was that the dust got inside the switch and interrupted the contacts. The switch is labeled as 1HP at 120V and the router is labeled as 1-1/2HP, so that had me a little worried, even though the switch looked factory original. In addition to 1HP, the switch is also labeled as 16A at 120V and the router is labeled as 8A. I think the router's claim of 1-1/2HP is overly optimistic, so I put those worries out of my head. The switch was riveted together, but when I tried to drill the rivets out they just spun. I switched to a rotary tool with a diamond grinding bit to grind the rims of the rivets without them spinning. Once I got the switch open I could see it was filled with sawdust. The dust had mixed with the grease inside the switch and I knew that got between the contacts and caused of the interrupted power. There were no signs of arcing on the contacts, so I cleaned everything up and reassembled the switch with some small screws and nuts.
When I had the router apart, I checked the bearings. They seemed a little sloppy, so I decided to replace them. The front bearing slipped off (not a good sign), but the rear needed a puller. I don't have a gear puller, so I made a simple puller out of some bolts and a piece of flat bar. The bearings were non-standard sizes, so I had trouble finding replacements. Both were 1/2" thick, but the rear one was 30mm OD x 10mm ID and the front was 1.375" OD x 0.625" ID (or so I thought). It seemed odd to use one metric bearing and one inch, but they were both non-standard thicknesses, so I figured it was just a goofy design. The diameters of those bearings are standard sizes, but those standard bearings are both thinner than 1/2". I ordered the standard bearings and figured I would just make some spacer rings. The rings were just a matter of some simple lathe work. When I went to assemble the router, I discovered a problem with my measurements. The rear bearing pressed on fine (in a vise), but no amount of pressure would seat the front bearing. I measured the bearing and it was true to size, but when I measured the shaft, I found my mistake. When I measured before ordering, I used dial calipers calibrated in inches. I thought the measurements were exactly 1.375" and 0.625". When I remeasured with a micrometer, I realized they were 1.378" (35mm) and 0.630" (16mm) which is a standard metric bearing size. Since it took the US post office 2 weeks to deliver my bearings (they were only going from Illinois to Pennsylvania), I didn't want to wait for new bearings. I decided to chuck the armature in the lathe and polish the shaft down to the proper size. It only took a few minutes with sandpaper. Once I got that straightened out, the assembly was easy. The switch seems fine and the router runs without shutting down.
This router doesn't have a spindle lock like my other one. You need to use 2 wrenches: one to hold the spindle and the other on the collet nut. The spindle nut sat partially inside the router body, so there was only room for a wrench about 3/16" thick. My Craftsman wrench is about 5/16" thick. The spacer ring I made for the inner race raised the spindle nut slightly, but my wrenches still wouldn't fit. I decided to make a simple wrench out of 1/4" x 1-1/2" flat bar. I laid out the design with a scriber on top of Sharpie and used my band saw to cut the rough shape. I used the [newly fixed] belt sander to finalize the shape of the wrench, then used the mill to make sure the opening was square and fit the 13/16" nut.
Click the pictures for larger images.