Basically assembly is the reverse of disassembly. I first reinserted and sealed all the set screws I found on the main body. I then lubed the front chuck bearing and inserted it into the body. I rotated the assembly so it was resting on the chuck face.
Next, reattach the brake plates the chuck - noting the correct dish position. Here I had to guess because I didn’t realize they were dished when I took it apart. Based on the marks the screw heads left, I choose have the center higher section toward the rear. It’s hard to see, but the center is higher than the outside edge. I placed it with the highest part to the rear.
Now install the 3 brake piston o-rings in the body (HDW-0176) and the 2 o-rings in the center of the piston (HDW-0167). I used some silicone grease for lube, I suppose oil would be fine too. You probably want something to ease the assembly. Now insert the brake piston.
Next is the back plate (ROT-0033). Install the two outer o-rings (HDW-0172) with some grease or lube. I also greased the nose section that locates inside the brake piston. You want to be careful about screw alignment as it’s a bitch to rotate when its home. Also there are two plugs that go at the top. I then installed the lip seal (HDW-0223). Unfortunately, I screwed up and drove it in way too far. It should be flush with the top of the bore. Remember to use a bit of sealant on the screw threads. At this point I installed the o-ring on the end of the chuck shaft (HDW-0164).
I forgot to take a picture of the preload ring being installed. Since I had no information on what it should be preloaded to - I guessed at 90 ft lbs. I figured the bearings where very large and there might be significant lateral cantilevered loads on the chuck face, so it better be tight. Hopefully it’s close. If you know let me know! When it was torqued up it rotated pretty freely and had no tight spots or “notchiness”. I got to use my tool from Part 1 to torque it up!
Next was inserting the worm (ROT-0037 + ROT-0043), from the motor end. Then sliding the adjuster plate (ROT-0043) on the opposite end. Unscrew the two screws on the top and bottom of the adjuster plate so they are clear of the hole. Push the adjuster plates down so they are resting on the top of the pin.
Thread on the Higgins nut on on the non-motor side. Note that there is a 0.015 or so boss on that goes to the inside.
Now insert the motor drive gear on motor end of the worm, locating with the key. Note: the boss on the gear goes toward the inside. Thread on the Higgins nut, noting it’s boss goes to toward the gear face.
Hand tighten the Higgins nuts. Make sure the adjuster plates are fully down on the tops of pins, to create maximum clearance with the worm gear. You should be able to freely rotate the worm and the chuck should spin nicely with no bindings etc. There will be some backlash, however.
At this point you need to read the maintenance section of the Options Manual. See Options Maintenance Manual. It gives detailed instructions on how to set up the worm, the backlash and tune the amplifier, etc. I’ll cover some this stuff later.
First is setting up the worm. The adjuster plates basically pivot up and down around a locator pin. The other pin is the one between the two screws and is in a hole that’s oversize enough to allow for a range of motion. By screwing in the top screw, and therefore pivoting the adjuster plate upwards, you’re also bringing the worm closer together and reducing backlash. You need to raise both ends of the worm evenly so we reference it off a surface plate.
The procedure is to screw the top screw on the non-motor side in one turn (after just contacting the pin). And screw the motor side one in two turns. Now zero an indicator on the non-motor side (pick a spot that will be same on both ends as it makes a difference. I used an area just outboard of the screw center line.
Now carefully transfer this reading to the motor side and adjust it either up or down to read the same. At this point the worm should be level and backlash should be pretty much out. In my case I felt I had a bit too much backlash, so I raised the non-motor side about a quarter turn and re-leveled the other end. Hmmm, too tight. So I backed it off a bit, re-leveled. Note: you’ll need to push the plate down if you unscrew the top screw - i.e. don’t assume it moved down just because you took pressure off the top. After 3 or 4 attempts I managed to get it so there was a bit of backlash, but it didn’t bind. You should check all 360 degrees. Don’t install the end plate or motor plate just yet.
Now install the large lip seal in the front (HDW-0224). I had a hell of time getting that in, so I won’t relate it. It was just wrong. Probably need to create a ring to be able to uniformly press it in. I can tell you now a small ball peen ain’t the way to do it.
Once that was in and the retaining screws were installed (with sealant), install the zero indicator plate, loosely. I would rotate the chuck so the line is in approximately the correct position and the T-slot is horizontal.
OK the hard part is over! Next is mounting the motor. Replace the 1/4″ o-rings (HDW-0149) on the motor side of the motor end plate.
Lube the lip seal (HDW-0225 - I didn’t replace this on mine as it looked fairly new) and slide it into the motor. Tighten down the 4 mounting screws. Now place the gear and clamp on the motor shaft. Note: the beveled end of the clamp goes against the gear.
Reseal air fitting and run one of the HDW-0162 o-rings around the outer groove. Put 3 more around the periphery. I used Gasgacinch to glue them in and some blue painters tape to hold it until the glue set. It seemed to work well enough. As the British might say, “offer the motor to the body” and secure with the 10 bolts. Don’t forget sealant on the threads (esp the through holes).
Carefully slide the motor cover on and secure.
At this point, you’re ready to mount it in the mill and set up the final adjustments. The end plate opposite the motor should still be off!
After you hook up the electrical cable and air line, there are 6 things left to do:
My amp board was sort of hacked in - that’s why that electrical block is sort of hanging in space right in front of it, etc. Your mileage may vary. Here’s where you adjust SIG2 on this amp board.
I ended up adding a 0.0007 backlash at the control (as in BL,4,7) and it seemed like I ended up with backlash around 0.0003.
Once you have everything adjusted to your liking, mount the end plate and fill with oil. Before you reinstall the top fill plug, run it back and forth and wait at least 10 mins. You’ll probably need to top it off. After it’s settled down and the level is stable, tighten the plug. I would watch the oil level over the next week or so to make sure there are no leaks