Dan, thanks for the information. I looked at the Mazzer information and it is similar to the Macap but, in my opinion, the Macap is much simpler. (I managed to figure out how do to this on my own and with the limited information that 1st-Line sent down to me.) There are no tension springs to deal with in the Macap. When you rotate the worm gear thumbscrews you are moving the upper burr toward and away from the spinning lower burr by means of a very fine thread on the upper burr. The very fine thread allows for very fine adjustments. So here's the drill if anyone else ever needs to do this:
1. Remove the bean hopper.
2. Remove the three tiny phillips head screws that hold the black plastic hopper gear (the one with the useless numbers on it) to the upper burr assembly and lift that plastic gear off. As you face the front of the grinder, you lift the front edge of the gear up and pull it back out of the worm gear teeth. Very easy to do and you can leave the worm drive in place on the grinder.
3. Once that gear is removed, you simply unscrew the upper burr assembly that the gear was attached to. This is very similar to the Mazzer and you turn it clockwise to remove it. It's a very fine thread and silky smooth.
4. Once the threaded upper burr assembly is out you can easily clean it with a toothpick, paper clip or some other sharp pointy object, but take care not to get grounds in the fine threads on the outside of this piece (more on this later).
5. The inner burr is fixed to the motor drive shaft down in the throat of the grinder. I used the same implements to clean that one, again taking care not to get coffee on the inside threads in the throat (a little trickier) and then I vacuumed the throat out.
6. The information I received from 1st-Line said to clean the threads of any coffee grounds on both the upper burr and the threads in the throat with a cue tip dipped in olive oil. You don't need a lot of oil, and I sort of rotated the cue tips while moving them back and forth parallel to the threads. Work a small section at a time and work all the way around. I went through about a dozen cue tips to clean both threaded surfaces. The 1st-Line information was also emphatic about not getting any oil on the burrs just as you mentioned in your response to me.
7. Once all cleaned up, you simply set the upper burr assembly, thread side down, on top of the throat of the grinder and gently, without applying any downward pressure, rotate it in the clockwise direction (the direction to loosen) until you feel the first thread drop into the upper thread in the throat. Make sure it's straight up and down and you can jiggle it a little as you gently rotate it until you feel it engage. Once engaged, and without applying any downward force, slowly start to turn the upper burr counterclockwise (tightening direction) until it freely threads into the unit. Once it starts in you'll get the same silky feel that you had coming out. If it feels like it's binding up, even the slightest bit, back it out and start over. If it doesn't feel silky smooth, back it out and check for grinds on the threaded surfaces again.
8. I threaded the upper burr in until it touched the lower burr, you can tell by feel but if you want to get a more accurate location you can rotate the the shaft that sticks up from the lower burr while gently turning the upper burr until you just feel the burrs touching one another. This is the zero position (burrs touching).
9. Once you have the zero position, you can put the black plastic gear back on. Angle it in from the front of the grinder so that the teeth on the gear engage the worm gear teeth taking care that the three holes in the gear line up with the threaded holes in the upper burr. I had to wiggle the gear around a little to get it to seat on the upper burr surface, but it wasn't hard to do. You shouldn't have to force this on.
10. Since there are three screws holding this gear on you can position the gear in three different positions. I selected one that allowed one of the numbers on the gear to align directly on center of one of the larger screws that are on the top of the grinder housing outside the upper burr gear (I assume these screws hold the motor in the housing). In my case the number 9 aligned with the screw on the lower right corner of the housing. I now know exactly where my zero is and no housing marks were required!
11. From zero I opened up the grind the 2-1/2 numbers that everyone says is the sweet spot for espresso (or roughly 1/8 of a full turn of the black plastic hopper gear, this is a clockwise rotation of the gear) using the thumb screws.
12. Replace the bean hopper and you're ready to go.
That's all it took. It probably took me 30 minutes to do the above, and I had a lot of scraping to do on both burrs. In my case, the 2-1/2 setting from zero was too coarse for my Elektra Micro Casa-a-Leva machine, but a few more fine tunes (this time while the grinder was running) and I was back in business. I may post some photos of this later on, but I think the process was so easy that these written instructions will probably suffice.