Thomas,
I have been using a Minolta Mod III since 1974 when I got one new for my birthday. I currently have it set up in my darkroom for teaching my kids about enlarging.
I bought a second one just to get the power supply, so I have a spare lamp house and dichroic filter mechanism that I don't use. I may have a spare mixing box also.
Issues:
1) The filters once got stuck so they no longer moved in and out. The dichroic assembly is a little tricky to disassemble but I got them freed up. Make sure all 3 filters swing in and out as they should.
2) My original power supply failed in 1977. Minolta service converted it to unregulated half-wave rectified 13V in 1977 with a couple diodes. It still works like that OK but I got a later model (different schematic) power supply a few years ago and the light is brighter at the appropriate 18V. I think the way to tell if you have the later model power supply is by looking at the bulb. If the bulb lights, you have the later (better) power supply. If the light is always off you have the early supply
3) The column tips forward a little after years of use. Two washers under the front of the column flange fixed it.
4) I really think you need the glass carrier to make good 16x20 enlargements from 35mm. That is a rare piece but I easily made one with two spare pieces of 4x5" negative carrier glass and some tape.
5) The foam rubber that presses down on the negative carrier itself when you lower the head turned to the gooey mess and needed to be replaced (McMaster Carr).
There is also foam rubber along the sides of the mixing boxes. This provided a light trap for the ventilation channel. These can be replaced with black electricians tape or any other type of flocking as nothing touches in that area.
6) I worry about the springs so I leave the head near the top (so the springs are coiled up, rather than extended) for storage. I have never had any problem with the springs. The manuals says you can lubricate them with petroleum jelly.
7) The manual does not cover this but the head is adjustable for alignment on the column. The top 4 of the wheels are mounted in eccentric rotating bushings. These bushings are held in place with very small grub screws and one of mine stripped right away back in '75. They provide a fine-tuning adjustment. I still needed to place the two washers under the front of the column for a 'coarse adjustment'
8) The lenspanel is fully adjustable for alignment.
9) Lensboards are very rare (I only have one) so now days it is easier to just buy lenses to fit the lens panel you have rather than trying to make or find a board with something other than Leica thread. Lenses can easily be changed by unscrewing.
10) A nice enlarger for people that like machined and extruded anodized aluminum rather than plastic. Even the case for the power supply is black anodized aluminum. I always thought it was designed and engineered very very well.
