Issue with Durst 138

[ATC]

Hi everybody!

It's my first post here ( i apologize in advance for how longwinded this is going to be) even though I've lurked around for a bit. I just came into ownership of one of these enlargers and I've got a couple questions for the Durst 138 users/owners (and anyone else who feels like chiming in) that either I haven't seen before or I missed in all my searches.

1) There is a problem with the focus knob for the bellows. It was only able to focus moving down the rod. If I tried to turn the knob to raise the bellows, the knob would just spin freely without moving the bellows unless I pushed up at the same time with my free hand. Figuring it was just some dried gunk causing it to slip i removed the back cover and it seems that over the years the steel of the rod chewed up the aluminum in front of where it sat. Is this anything anyone else has run into? Any ideas on workarounds?

This leads to number

2) I may have a line on some later version 138 parts namely the bellows/focusing portion of the head and the upper half of the main stand. Is it possible to mix and match parts from the earlier version with the later?

And lastly

3) To those of you who have brought one of these back to life what do you recommend cleaning the old gunk and oil off with, and what would you use to lubricate? Everything moves fairly freely on this one but there is a lot dirt and dried oil/grease everywhere, so I wasn't sure where to apply lubricant and what kind and I didn't screw anything up.

Thanks to anyone who wants to help, and this awesome community. You guys an gals have taught me a lot.

[ac12]

I clean the old grease with 99% rubbing alcohol. If you use another solvent, then wash it with rubbing alcohol to remove the solvent.
I used white lithium grease on the focusing rods of my enlargers.
BUT be sure to NOT put grease where the focusing rod connects with the vertical rod. It requires friction to do the job, so grease is NOT wanted there. The grease will just make the rod slip on the focusing rod. Only on enlargers that use a geared mechanism do you put grease in the gear.

That is what I did with my Durst L1000 and Omega D5.

[rcmartins]

Well, I did just that recently, recover a Durst 138 that is. I also that problem. The first and most important advice - do NOT put grease or lubricant in the focus knob or in the rod. It works solely based on friction. If you put lubricant or grease you will have a hard time recovering the friction back. If you look at that focusing gear with the plate off, just as you have on the photo you shared, you will see on top two lateral screws. Those work essentially to keep the mechanism vertical but also allow to increase and decrease friction. They have an optimum position. Try changing them until you fill it is right. I also helped the friction in mine by pressing the back plate harder against the steel rod of the knob. Even though I did not put grease I used a solvent to remove any oil that it had. After the cleaning, aligning and tightning of the screws I was able to bring the focusing mechanism to its splendor. It works a treat know. The good thing is that once it revives, it will keep on working without trouble.
Mine was also very dirty. I spent three weeks cleaning it part by part and assembling it together. I used an industrial cleaner taking care to avoid lubricating where friction is required. It is a wonderful enlarger, now.

[Drew Wiley]

There should be a little screw at the rear of the casting which slides over the focus rail, which you can adjust for friction.

[ATC]

Thanks for the help guys. I'm in the process of breaking everything down and giving it a good cleaning and lube where needed. I'll let you know how I get on. Overall I'm very impressed with the build of this machine. The machining is just about perfect everywhere.

[Drew Wiley]

A little TLC and these things last forever. I bought a nice 138 unit needing modest repairs, then an older 138 just for the parts, which are in fact largely interchangable. The main machine became a hotrod with my prototype custom color head (before I built my big 8x10 version), then I refurbished and converted the spare unit into an 8x10 coldlight enlarger. Just like working with antique cars. Sometimes takes a little patience and ingenuity, but after awhile, you've got an incredible machine on your hands.