Happy New Year! What will 2022 hold for us I wonder? For me there will certainly be more microscopes and plenty of lacquer. By the end of the year I should have completed my MA in preventive conservation too. I have been doing my MA part time and the first year went very well, my grades were good and I enjoyed it. I know more about relative humidity and antique conservation than I ever wanted to know and I am currently obsessing over the relative humidity in my workshop.
When the workshop was first built it had a few small leaks, the relative humidity was too high and mould developed around the edges of the room. I started monitoring the temperature and relative humidty and I bought a small dehumidifier which helped a great deal. Recently my dehumidifer broke down so I have a new one (a Meaco DD8L) which is much more energy efficient and generally more snazzy. Rather than running constantly like my old one did, it takes a sample of the air every 30 minutes and turns on if necessary saving a great deal of electricity. It certainly does what it says. You can see the humidity gradually increase and then drop again as the machine switches on. My humidity sensor is reading about 5% too low, but you get the idea.
Brass and Glass has a new snazzy website with a new snazzy logo. I’m very pleased with it, I think it looks a bit smarter and it feels more personalized and special now.
My husband is the bearer of a coat of arms (technically his father is the current bearer, but let’s not split hairs). The Thoyts coat of arms consists of gold stars (mullets) on an azure background. In heraldry, the stars originally represented a knight’s spurs although it isn’t always the case. The symbol for the planet Venus is also present and it is unclear what meaning this has, if indeed it has any meaning at all. The meanings of heraldic symbols can be bad puns, their meanings can be lost in time or sometimes they are only there because they look good. The crest is a heath-cock (grouse) rising with the Venus symbol on its chest.
Through marriage the Thoyts family combined their coat of arms with that of the Burfoot family, and I have loosely based my logo on this. My family does not have a coat of arms because I come from a long line of non-conformist peasants, so for my contribution to the new coat of arms I substituted the Burfoot stars for microscopes while keeping the black background. I’m sure the Burfoots would be horrified.
Click on the thumbnails below to see the progression of the Coat of Arms
This is Ernie, he’s a Reichert and he used to work in milk testing. Unfortunately, I forgot to take a picture of him before lacquering. He had some deep scratches. I wasn’t able to get all of them out on the tube because of the enormous amount of engraving on the tube but I managed to get the really bad ones out of the foot.
I did take one picture of Ernie before he was lacquered, just the foot. I took the picture because I was impressed by the difference in colour between the faded and unfaded areas. Where the upright was attached to the foot, no light could penetrate resulting in a dramatic colour difference.
Never, in the history of microscopes has a microscope given me so much trouble. I don’t know why but this piece of a Reichert just did not want to be lacquered. I did it again and again and again. It ran, it dripped, it missed bits. I tried using cloths, pads, brushes, foam, I tried hot, warm and cold metal. The thing was out to get me.
It happens sometimes, you just have a bad day, but the good thing about lacquering microscopes is that if you mess it up you can just take the lacquer off and redo it. Not that that is much comfort on the third day of trying having used up 100 mls of lacquer.
I got there in the end. The Reichert (whose name is Ernie) is now my friend again. Now for the trickier bits.
This Oberhauser drum microscope needed a new mirror and a new condenser. The condenser arm and holder have been made using a coping saw and hand files and special screws were made which allow the condenser arm to be repositioned whilst remaining firm. The condenser mount was made on the lathe. It just needs painting olive green now to match the rest of the microscope. It can be removed and fits neatly into the box with the rest of the microscope as the original would have done.
This microscope does not need any relacquering as the original lacquer is still 99% intact. I have taken some pictures using the microscope – one is of a xylophyte stem and the other is of radiolarians.
Oh the poor little Verick! In a photograph there didn’t seem much wrong with this Verick apart from the total lack of lacquer but it had serious issues. The Tube holder was stuck fast, the tube was stuck fast in the tube holder and it took several hours to get it all unstuck. The cause? Brasso. Don’t use brasso on your microscopes, it removes the lacquer and clogs up the moving parts it’s like glue. Below is a picture of the aperture ring which was also stuck fast and what it looked like inside when I finally got it apart.
There is hope though, if you can get the microscope apart the brasso can be removed quite easily. Here is the little Verick before and after lacquering, all parts are now moving smoothly and it is ready to return home.
This beautiful little Plossl had been mistreated, either stored in an attic or garage, or otherwise abused. Very little lacquer remained and that which did was decaying casuing corrosion and pitting to the metal. I have stripped off the old lacquer, removed the corrosion and polished without removing all the scratches and pitting that show the age and history of the microscope. They are simply safely locked away under new lacquer which should protect it from any further degradation. I have not lacquered the mirror or the objective as the risk of damage to them by polishing and hot lacquering was quite great. I’m rather pleased with it.
Today I’m preparing to silver a mirror. I use the Rochelle salt method as follows:
Solution 1: Silver nitrate 2.48 grams, silver nitrate 2.07 grams, distilled water 473mls, 25% ammonia as required.
Dissolve 2.48 grams of silver nitrate in 120mls water stirring with a glass rod. Add around 30 drops of ammonia, the solution will go dark and will then gradually clear again. Once the solution is clear add the rest of the silver and swirl until dissolved. Add the remaining water. Leave to settle for an hour or two then filter and store in a dark bottle labelled Solution 1.
Add 1.56g rochelle salts to water in a glass vessel and bring to the boil. After boiling for 1 minute add the silver nitrate and boil for a further 5 minutes. Leave to cool then filter and store in a dark glass bottle labelled Solution 2.
Thoroughly clean and de-grease the glass to be silvered and tape up any areas on which silvering is not required. Warm the glass to about 38C with warm distilled water, when warm, drain off the water and cover with a 1:1 mixture of solutions 1 and 2. It is best to warm the solutions before mixing them together. Swirl the mixture over the glass for around half an hour then pour off the solution, rinse in distilled water and leave to dry. Gently paint the back of the mirror with a suitable paint to protect it from abrasion.
I bought this Spencer jug-handled microscope some time ago, at first glance it doesn’t look too terrible, a broken mirror holder and a missing mirror; but if you look again you will see that the poor thing has been spray painted black from top to bottom. The objectives, the coarse and fine focus knobs – everything is painted. This is a serious rescue, I have never had to use paint stripper on a microscope before but this calls for desperate measures. As you can see in the last picture, so far not too terrible, there is hope. I have stripped the black paint off the focus knobs, and underneath the paint the coarse focus has polished up pretty well. I have to de-corrode the other parts and see if I can get a polish on them good enough for hot lacquering. It’s not so much a restoration as a salvage operation, but I have a soft spot for jug handled microscopes. Wish me luck!
I have been restoring this lovely little Merz microscope, it’s a very special, rare microscope so I want to be careful not to over-restore it.
Below is a picture of it as it started out, as you can see it is fairly grubby. The stage has lost a great deal of its chemical blacking and there is verdigris on the foot where there is paint missing. There is no lacquer on the tube and the metal has become extremely dark. Of course, many people like the look of patinated brass, but to me, a completely blackened piece of brass is beyond a patina and certainly isn’t what the original maker would have wanted.
The first step in the restoration process is to clean the microscope inside and out. Corroded screws and small parts were placed in an extremely mild metal de-corroder. Larger parts were cleaned carefully by hand using decorroder or pre-lim as appropriate. Below you can see the tube in various stages of cleaning. Note that once the tube is cleaned you can actually see the guide lines the engraver used to keep his lettering a consistent size!
I have got to this point without using any harsh abrasives – no sandpaper, no polishing, nothing that removes any metal. Just de-corroder and pre-lim. Whilst there is still a very small amount of staining and a few small pits I did not remove them and went straight to a very, very, light straight-graining followed by lacquering.
The finished tube. You can still see the engraver’s guide lines and note that the un-lacquered parts of the microscope tube have been cleaned but have not been polished or otherwise altered.
Now for the paint, the paint is a mixture of dark umber and ochre pigments ground on a ground glass sheet with a muller. Linseed oil is added until a paste is formed, it takes a long time to get rid of all the lumps. The linseed and pigment paste is then thinned with tung oil and turpentine. Tung oil dries better than linseed alone and gives a higher gloss.
I have not re-blackened the stage as I do not want to take away all signs of age and character. There are a couple of deep scratches on the stage though which look to be fairly recent and I shall probably blend them in a bit by blackening just the troughs of these scratches which are currently showing bright brass. I can do this by thickening the blackening chemical with PEG and painting it into the scratch marks with a very fine artist’s brush in much the same way engraver’s fill their work. That way it won’t affect the rest of the stage.
In the next post I shall show the reassembled microscope, right now the paint is drying.