LOMO biolam C1

[smollerthings]

Hi Everyone,

I am a newbie thinking of getting a vintage LOMO Biolam C1 microscope. It is quite complex and I have a couple of questions.

1. The objective lenses. Despite reading this article:
http://www.microscopy-uk.org.uk/mag/ind ... iolam.html

I can't figure out if the objectives are stardard DIN and if I can buy a normal DIN 20x objective on Aliexpress like the one below.
https://www.aliexpress.com/item/4000427 ... LMThw&mp=1
Also the aliexpress lens is specified to be 195 mm, what does this mean?

2. My microscope doesn't come with a mechanical stage, I found some that can be adapted like this one
https://www.aliexpress.com/item/1005002026637916.html
Would that work?

Thanks!
Chris

[MicroBob]

Hi Chris,
the Biolams were designed with 160mm tube length, ca. 33m objective parfocal length and c
intermediate image ca. 13mm down the tube. This is close to old Zeiss Jena dimensions wich is what the Biolam was copied of and the simpliefied. So this is not DIN (160-45-10). Objectives with tube length 195 are not DIN conform. Here in Germany basic Biolams are plenty on the used market and all basic components are readily available so no one would bother with fitting chinese stuff.

The biolams are nice microscopes. The oldestround model is a straight copy of the Zeiss Jena LG, my one was made very well. The first angular model has a geared fine focus which is nicer to use but doesn't resist abuse, the later model with disc fine focus is especially easy to dismantle and re-grease and very robust.

Bob

[Leitzcycler]

I agree. Why not buy Lomo objectives for Lomo microscope? They are not so expensive in Ebay.

I may have some Lomo stuff I don't need, however don't remember if there was 20x objective. Do you have 90x immersion objective?

Is your model C1 monocular or binocular head?

Where are you located?

[Dubious]

You do want an X-Y stage/slider, which will make finding (and chasing) things on the slide a lot easier. If you can't find a compatible LOMO slider, the generic one you linked costs so little that buying and trying it is not much of a risk. The stage of your LOMO may already be drilled for it (I once found that the case with a "toy" microscope and a cheap Chinese X-Y slider--apparently there was some standardization) but even if not, you can probably find some easy way of attaching the X-Y slider--use a clamp; drill holes; whatever--so long as the stage is large enough to accommodate the slider, and it most likely is.

[smollerthings]

Thanks guys for your responses and sharing the knowledge.

@MicroBob Pic of the microscope below. I guess this is the angular version?


It then makes much more sense to get the Lomo objectives. I think I will first get my hands on this (new, never opened!) biolam and take it apart to regrease it. If it survives my lack of skills, I will try it and see if I need the 20x. The original box includes the 8x, 40x and 90x oil. I don't see myself use the 90x oil, being a lazy fellow, so I was thinking of getting the 20x.

@Leitzcycler
I am located in France. It is the monocular version.

Thanks @Dubious. I will probably just do that for the slider. Not too much risk involved

Cheers!

[Lomonaut]

Good idea to get a 20x for it. If you can find a Lomo 20x/0.65 apo, go for it! Not plan at all but a very sharp image, one of the few objectives that benefit from a 20x eyepiece.
Looks like those are Kompensation eyepieces, they should be fine with Lomo apo's.

There is the 20x/0.40 achromat too, just a standard 20x. Actually, Lomo had a huge range of objectives: water and oil immersions, apos, plans etc.

Congratulations, it should be fine after the re-grease!

[MicroBob]

This is what I called the angular version, earlier edition with geared fine focus, similar tonthe Zeiss Jena LG's. In the LOMO Infothek you can find all information and probably a maintenance manual for this model. A nice expandable microscope and fairly compact and light. Don't move the gummed up fine focus before relubricating it. The included immersion oil shouldn't be used but disposed of properly, it might contain PCBs or otherwise gum up quickly.

With these Biolams cheap on the market I don't understand the popularity of cheap chinese microscopes....

Bob, who has one Biolam and one Biolam based DIY field microscope and an old, round Biolam field microscope...

[smollerthings]

I am very excited...

Lomonaut, I think I will just get a 20x 0.4 achromatic. I think it will be useful. I was hesitating between the 20x or a 60x dry. But I think 40x is already good magnification.

Bob, what kind of lighting do you use with your lomo? Does a regular light suffice?

[Leitzcycler]

I was hesitating between the 20x or a 60x dry.

I have a 60x dry objective. The image is really very bad. I don't know if it is somehow damaged or are the all 60x Lomo objectives the same.

Sorry, I don't have an extra 20x. I have one 20x Apo which I will keep in my set. It is of high quality.

[Lomonaut]

I have a 60x dry objective. The image is really very bad. I don't know if it is somehow damaged or are the all 60x Lomo objectives the same.

Sorry, I don't have an extra 20x. I have one 20x Apo which I will keep in my set. It is of high quality.

But I do have an extra Lomo 20x/0.40 - I haven't used it since the 20x/0.65 Apo arrived, back in.. eh.. 1986? It should be fine, it came with student microscope MBU-4. I'll keep that 20x Apo, just like Leizcycler - sorry!

Another one I hardly ever use(d) is the 60x/0.7-1.0 Apo oil. The diaphragm is stuck (hardened lubrication) but hey it's apochromatic.

Here's an idea smollerthings: if you manage to clean up, re-grease this Biolam and get it operational, they are yours!

[Leitzcycler]

Have a look at this thread viewtopic.php?f=5&t=9121&p=80556#p80556
and see the picture showing the Biolam focusing system dismantled. After cleaning and relubrication, make sure the pin lifting the coarse focus block stands exactly upright so that it will go into the hollow when you slide the arm back.

I previously thought the jammed grease is a specific problem ofwit Lomos... until I bought an old Olympus FH. It was much much worse. I ordered the new greases from Osim Optik Germany. They will assist you which type of grease would be best.

[smollerthings]

Thanks guys, I'll post some updates when I get that gem.

@Lomonaut, thanks for your offer! It is very kind.

@Leitzcycler How important is it to get the right grease? I was just gonna get a high quality PTFE grease like this one
https://www.amazon.fr/gp/product/B000XBH9HI

[Leitzcycler]

How important is it to get the right grease?

Unfortunately I am not an expert in this. Your grease might be just fine. There were some discussions about this subject in this forum. You may find them if you search.

It was maybe 30 years ago when I got my first real microscope. It was a university surplus Biolam. It was stuck in every way and when cleaning and relubricating I used an ordinary machine grease. No problem. Of course I knew almost nothing about microscopes at that time...

[smollerthings]

Unboxing of my new vintage biolam C1.
42 years after its manufacturing date!!!
What an exciting adventure...



Now I need to make it work

[smollerthings]

I am a bit lost. There is not enough instructions on this guide for me to get started...
http://www.microscopy-uk.org.uk/mag/ind ... wlomo.html

Everything is seized, where should i go from there?

[MichaelG.]

Everything is seized, where should i go from there?

https://imgur.com/a/Ly4XJL1

Buy some kerosene-based ‘dismantling fluid’ and apply it sparingly to the joint-line of any components that are seized
… leave it for a day or two, then gently test for movement
… repeat as neccessary

Don’t force any of the mechanisms !

MichaelG.

.
My own favourite is PlusGas ‘Formula A’ but you should easily find something similar.

[smollerthings]

Thanks! I don't have PlusGas in France. Will try WD40.

[BramHuntingNematodes]

watch out with pressurized spray solvents and fluids they can get into dumb and bad places

[Leitzcycler]

I have also used WD40 or similar product. It is possible to get only a drop or two by pressing very gently. It needs some practice though. However, you may need to dissolve the old grease by dipping the mechanical parts into petroleum anyway. That means you need to take everything apart. Do not use force with jammed mechanism or you may damage them. For instance, the condenser gear is made of plastic and is very easily damaged if you try to move the jammed condenser holder.
For some parts you may use gentle warming with a hairdryer.

[smollerthings]

I am quite new at this and I have some difficulty to take it apart...
I don't understand how I can take the dovetail apart without sliding it out? (and I can't slide it out because it is seized...)
I must be missing something.

[Leitzcycler]

The idea is to first soften the hardened grease using WD40 and perhaps by gentle warming. WD40 will penetrate into the dovetail surfaces when applied from top and/or side. Taking the arm apart (sliding) is more easy if you have it fixed into the base. From the pictures I see you have taken it apart. What I did, is that I lifted the arm with a big, flat screwdriver very carefully while turning the coarse focus knob simultaneously (some cardboard around the screwdriver head for keeping the surfaces not to get scratched). Maybe is better to remove the coarse focus knobs and axle first. The fine focus block is freely removable after you have removed the plate with a serial number (two screws and a spring under). Screwdriver between the block and base and gentle lift. There are good pictures in the link you posted.

I don't take any responsibility advising using the screwdriver. The method needs some patience and skill.

[Leitzcycler]

These might help
http://www.microscopy-uk.org.uk/mag/art ... mbly-E.pdf
http://www.microscopy-uk.org.uk/mag/ind ... lamps.html
https://blog.lidskialf.net/2020/08/18/r ... icroscope/

[Leitzcycler]

Maybe is better to remove the coarse focus knobs and axle first

This may be difficult as the axle slides away to one direction only as far as I can remember (when knobs removed). I cant say which way in your microscope. The Biolams I have refurbished have been older models with different type of coarse focus knobs. So I can't advise you with this part.

[smollerthings]

Thanks for all the info. The first link is a gold mine! Just what I was looking for. Hopefully I will make some more progress tomorrow.

[MicroBob]

Did you find these repair infos: http://www.mikroskopfreunde-nordhessen.de/lomo.php

[Chas]

-Cigarette lighter fluid (not the gas) is really good at softening the hardened grease and it doesn't have oil in it.
Leave it 5 ot ten minutes or even 20, if 'whatever' doesn't want to move ...apply some more fluid wait another ten minutes and try again.
Have plenty of paper around as the grease is really disgusting.
And if you were sensible and have a pair of those thin gloves I would use them .. the dissolved grease really gets into your skin and stinks.
-Once you have removed the the black-coloured plate with the numbers on it, everything becomes more obvious.
Have fun

[smollerthings]

I was successful in unfreezing everything!!! I am so happy. Thanks everyone for your help.

Unfortunately, in the process, I broke the condenser's plastic slide. Oh well, it could be worse.

Now quick question, what would happen if I used light oil vs grease on the sliding surfaces? Is the only inconvenience the damping action?

[Leitzcycler]

I warned you... So you lost some gear tooth? How badly?

There are places where there should be high-viscous grease e.g. the coarse focus dovetail surfaces. The coarse focus should be tight rather than loose. Light oil is used e.g. in diaphragms. However, when refurbishing my Olympus FH microscope I noticed there was no oil of any kind in the diaphragms and they were the only parts not stuck. So I think it might be a good idea not to oil them at all.

[Hobbyst46]

However, when refurbishing my Olympus FH microscope I noticed there was no oil of any kind in the diaphragms and they were the only parts not stuck. So I think it might be a good idea not to oil them at all.

I second that. Diaphragm blades should be dry.

[smollerthings]

A couple of teeth indeed top position. I think I will have to push to get the condenser down now.
But I understand that I will mostly leave the condenser on top position anyway.