The Merz has an interesting design, and not one I have seen before. Most microscopes of this age and style have a solid round bar through which a triangular bar passes. The triangular bar has a screw at one end and a spring at the other and it’s a very effective, simple fine focus mechanism.
The Merz has a rather different set up – it also has a triangular block with a screw at one end and a spring at the other, but instead of passing through a round bar, the triangular block passes through another triangular piece. The outer triangle is constructed from pieces of flat brass which have been joined together by brazing – this might explain why Merz painted these parts rather than lacquering them I think. Using brazed pieces of brass would have saved a lot of wastage and money and it would easily have been strong enough.
A “typical” round Baker fine focus block on the left, the Merz brazed, triangular fine focus mechanism on the right.
Travel could only have occurred in a small area. The solid triangular bar has a cut out area and a small bar is inserted through the corner of the brazed piece which acts as a stop. The pictures make it much easier to understand.
I have so many lovely microscopes that need work and I am like a child in a sweet shop, I don’t know which to do first! I’m overwhelmed with wonderful choices and I need to make a decision. I would like to get something underway this week. I have a beautiful double pillar microscope which needs a screw making and a bit of a clean but I don’t really think it needs re-lacquering. Do let me know if you agree/disagree with this opinion. I enjoy re-lacquering more than anything else so I shall probably leave the double pillar for another day when I’m in more of a making screws mood.
I have the Merz which is simple to do and in need of lacquering, I have “the Beast” which is huge and will take many months to do. a selection of small Hartnacks and the like and a rather nice jug handled microscope which has been painted completely black and really needs some love. When I say it has been painted black, I mean completely painted black – even the objectives. Poor little thing.
I think I’ll start with the Merz and then move on to the jug handled microscope. Decision made. If I don’t post pictures of a dismantled microscope tomorrow feel free to come and beat me with a big stick.
Pb or not Pb? that is the question. Pb is the chemical symbol for lead, today I shall be talking about lead. Hilarious aren’t I? ( please don’t answer that).
I have a new baby to work on. You can see below that it has a patch of corrosion on the foot which has to be treated before if spreads. I shall treat it with a gentle rust remover, sand the area and prime before painting. Here’s the tricky bit – I like to use ingredients and techniques that are as authentic as possible. I am pretty sure that the original maker would have used a lead oxide primer. I can’t buy lead oxide primer and although I can buy lead oxide powder, it is very expensive and it’s not a clever thing to be working with. Also, the chances of me ingesting some are quite high, because I tend to lick things if I don’t have a damp cloth to hand. I shall be using a commercially available non-ferrous metals primer instead, it won’t show underneath the paint anyway. Interestingly, I can see brush marks in the original paintwork so they weren’t being all that fussy.
I shall be starting on it as soon as some brown paint pigments arrive from my chums at Ingilby. I need to mix my own paint for this one. For a bog standard black and chrome 1950s – 1970’s microscope I tend to use black enamel paint. either Japlac or a reasonably high temperature coach enamel, sometimes with lacquer on top, sometimes not. This baby is special, it is also much older than 1950 and painted brown not black. Below is my paint mixing kit: pigments, linseed oil, a large ground glass sheet and a muller. Hopefully the brown pigments will arrive tomorrow.