First is a view using a Reichert Univar microscope with a low-power objective (Reichert Plan Fluor LWD Epi IK 10x/0.20 ∞/0), then a repeat with a higher magnification (Reichert Plan Fluor Epi IK 50x/0.85 ∞/0.
Friday, February 15, 2019
Epi DIC of an integrated circuit
Here is a video I made of an uncovered integrated circuit, viewed using epi-illuminated DIC (reflected-light differential interference contrast), and cycling through the various appearances of the IC circuitry as the upper prism is moved through the optics of the microscope. Note the changing look of the circuitry, how the contrast and clarity changes, a key reason why this technique was used to troubleshoot ICs during development.
First is a view using a Reichert Univar microscope with a low-power objective (Reichert Plan Fluor LWD Epi IK 10x/0.20 ∞/0), then a repeat with a higher magnification (Reichert Plan Fluor Epi IK 50x/0.85 ∞/0.
First is a view using a Reichert Univar microscope with a low-power objective (Reichert Plan Fluor LWD Epi IK 10x/0.20 ∞/0), then a repeat with a higher magnification (Reichert Plan Fluor Epi IK 50x/0.85 ∞/0.
Tuesday, January 1, 2019
Relubrication inside a Reichert/Leica Microstar IV microscope
A friend recently complained about a shuddering in the focus travel of their Reichert Microstar IV, and inquired about lubrication. Below is an edited version of my response.
The Microstar can certainly profit from relubing certain areas. Here are a few lube points that can be easily done. I use a synthetic oil with an extension needle-tube on the end, one of these:
https://www.ebay.com/itm/LARGE-2-oz-Liquid-Bearings-with-EXTRA-LONG-3-needle-BEST-100-synthetic-oil/230963683534?epid=1554654191&hash=item35c68220ce:g:6OkAAOSwfztbURIi:rk:3:pf:1&frcectupt=true
I originally got it for clocks, but it seems like good oil, and the extensions are handy.
Places to clean and lube to fix jerky focusing:
1. With the scope right-side up, remove the top plate (5 screws under covers); you can then raise and lower the inner movable casting that holds the nosepiece turret with your fingers.
***
Do not drop the turret after raising it! The inner casting (holding the turret) rides up and down on a cam affixed to the focusing shaft (you can see the cam if you peer down past the neutral-density filter when the scope is upside down). The plastic/resin cam is fragile (the repair of which is my next post) and can be broken if the inner casting is raised and dropped too hard, or if the microscope is dropped; the ball-bearing cam-follower will apparently just punch right through the cam surface:
Which was thin plastic or resin (why they cheaped out on
certain critical parts, while doing a very good job overall,
boggles my mind).
***
You can see two guide ball-bearings, one on the left (fixed) and one on the right (spring-loaded). Check the outer race surfaces of these bearings as you raise and lower the turret. I've seen these bearing races broken or flat on the outer race, necessitating buying new bearings (they are a standard size, so available). Also the surface of the inner casting, where these small ball-bearings bear, might need swabbing with a q-tip w/ solvent (I recommend naphtha), to prevent a gritty feel if dirty. Oil the ball-bearings (they seem to be just shielded, not sealed); check them for excessive play, they shouldn't wobble sideways at all.
2. Go to the rear of the inner casting, and you can oil the shaft and drip some oil into the entry points of the upper linear bearing (it's not just a plastic bushing).
Flip the scope upside down, and lube the lower linear bearing (which is now above the other one) the same way. This is where the extension tube comes in handy. Also oil the cam-follower ball-bearing, accessible with the extension tube, from back near the lamp. Try not to over-oil, excess oil might run all over the cam.
3. Sometimes there is grit on, or a rough surface to, the cam surface that causes a bumpyness when focussing; inspect the cam surface and clean or polish if necessary.
Cam breakage or a messed-up cam surface is for a future post, and is not difficult to fix, but requires removing all of the focus gear, etc., and extracting the cam. Hopefully you don't have any of that. It is common to see, on bottom-dollar Microstar carcasses, messed up cams, missing filter holders, broken bearings, etc.
The Microstar can certainly profit from relubing certain areas. Here are a few lube points that can be easily done. I use a synthetic oil with an extension needle-tube on the end, one of these:
https://www.ebay.com/itm/LARGE-2-oz-Liquid-Bearings-with-EXTRA-LONG-3-needle-BEST-100-synthetic-oil/230963683534?epid=1554654191&hash=item35c68220ce:g:6OkAAOSwfztbURIi:rk:3:pf:1&frcectupt=true
I originally got it for clocks, but it seems like good oil, and the extensions are handy.
Places to clean and lube to fix jerky focusing:
1. With the scope right-side up, remove the top plate (5 screws under covers); you can then raise and lower the inner movable casting that holds the nosepiece turret with your fingers.
***
Do not drop the turret after raising it! The inner casting (holding the turret) rides up and down on a cam affixed to the focusing shaft (you can see the cam if you peer down past the neutral-density filter when the scope is upside down). The plastic/resin cam is fragile (the repair of which is my next post) and can be broken if the inner casting is raised and dropped too hard, or if the microscope is dropped; the ball-bearing cam-follower will apparently just punch right through the cam surface:
***
You can see two guide ball-bearings, one on the left (fixed) and one on the right (spring-loaded). Check the outer race surfaces of these bearings as you raise and lower the turret. I've seen these bearing races broken or flat on the outer race, necessitating buying new bearings (they are a standard size, so available). Also the surface of the inner casting, where these small ball-bearings bear, might need swabbing with a q-tip w/ solvent (I recommend naphtha), to prevent a gritty feel if dirty. Oil the ball-bearings (they seem to be just shielded, not sealed); check them for excessive play, they shouldn't wobble sideways at all.
2. Go to the rear of the inner casting, and you can oil the shaft and drip some oil into the entry points of the upper linear bearing (it's not just a plastic bushing).
Flip the scope upside down, and lube the lower linear bearing (which is now above the other one) the same way. This is where the extension tube comes in handy. Also oil the cam-follower ball-bearing, accessible with the extension tube, from back near the lamp. Try not to over-oil, excess oil might run all over the cam.
3. Sometimes there is grit on, or a rough surface to, the cam surface that causes a bumpyness when focussing; inspect the cam surface and clean or polish if necessary.
Cam breakage or a messed-up cam surface is for a future post, and is not difficult to fix, but requires removing all of the focus gear, etc., and extracting the cam. Hopefully you don't have any of that. It is common to see, on bottom-dollar Microstar carcasses, messed up cams, missing filter holders, broken bearings, etc.
Saturday, December 29, 2018
Reichert Microstar IV blue filter repair
Used Reichert/AO/Leica Microstar IV microscopes have frequently had a failure of the in-base blue filter holder. This filter holder
is made of a plastic, which over time from exposure to heat and UV from the nearby 20w halogen bulb, tends to break into charred brittle pieces. Not good!
Below is a simple fix I've implemented that replaces the broken holder with a more durable one.
(This fix is also detailed on the MicrobeHunter.com forum here, if you are interested in the forum give-and-take)
Here it is, mounted in place:
The simple new holder is made from a piece of scrap 6061 aluminum. The only slightly 'critical' dimensions are 1 through 5:
1. The large hole; it is 0.250" (6.36mm), for a slip-fit over the existing pivot bushing (which has an O.D. of 0.250"). If you have trouble getting a slip-fit, try reaming out the hole a bit with the edges of the drill bit. When mounted in place, the joint between the bushing and the bar can be lubricated with a little oil.
2. The small hole; it is 1/8" (3.16mm), for a slip-fit of the 1/8" stainless rod (5/8" long, super-glued and tapped into the hole to protrude about 1/2" (12.7mm). This rod is where the cable wire loops over the holder, to work the filter in and out of the light path.
3. The distance between the holes: center-to-center is 1.16" (29.5mm). This dimension was gotten from the original plastic holder.
4. The bar thickness; this has to be less than the length of the existing pivot bushing, so that when tightening the bushing screw, the bushing is secured, but the bar is still free to pivot.
5. The semi-circular slot (groove) for the filter glass is about 3/32" (2mm) deep, cut with a round saw or abrasive blade using a hand-held rotary tool (Dremel or equivalent, in the US), and having a width of a little more than the thickness of the filter.
The overall length of the bar is arbitrary, mine was about 1.8" (46mm). The bar width was about 0.485" (12.3mm).
I added the washer over the inner end of the bushing to keep the bar from wobbling as much. This was due to using a too-large drill bit (0.253"); if a tighter slip-fit is achieved by using a 0.250" bit, the washer is not necessary.
The best way to find the position of where the groove needs to be cut is to mount the bar in place in the microscope, swing it down into position, and mark the bar with a dotted line (see above close-up of the bar) where the OD of the field condenser diffuser glass is, behind the bar. This will give you the best place for the filter, whether 26mm or 32mm. Then remove the bar and cut your groove, glue in the filter, etc.
The groove for the filter is filled with Hi-temp RTV, the edge of the filter is cleaned and smeared with the same, and the filter is bedded into the groove, and the whole thing propped up to keep the filter planar with the bar, until the RTV hardens:
Then an additional fillet of RTV is applied to the bar-filter joint for extra strength. One could even skip the making of the groove (the most problematic part of the fabrication) and glue the filter edge directly to the side of the bar, but I didn't try this.
To test the RTV, I ran the lamp for several hours with the scope baseplate screwed on, to see if the temperature would be a problem, or if the RTV would fail, etc. No problems; the RTV got harder, the temp of the bar got up to no more than 130F (oddly 300F on the diffuser glass). The RTV supposedly can take 700F. Tugging on the filter, the RTV seems strong enough, but I didn't pull it out of the groove, so am hoping for the best. In service it is under almost zero stress, so I think it should work OK over the long term.
It may seem that the bar blocks some of the light, since some of the filter is recessed into the groove, but the lamp is so close to the blue filter, that if one traces the light from the filament of the lamp to the edge of the diffuser, one can see that only the center 75% or so of the filter is used.
Actually, the larger 32mm filters might be a bit better (if one can find a filter that is not too dark blue.)
To help the positioning of the filter when swiveled into place, some sort of 'stop' can help. The microscope has a pin for this purpose, underneath in the base, right under the blue-filter control knob:
The 1" lever worked by the knob runs up against the pin, to control the in-positioning of the filter. I've seen some of these pins bent to adjust the stopping of the lever, but personally prefer leaving the pin straight, and instead sliding a rubber cylinder, or the like, over the pin. This way, the pin doesn't break off from being bent, and changing the position of the stop is just a matter of changing the rubber cylinder size (one could even just wrap tape around the pin until it works).
Below is a simple fix I've implemented that replaces the broken holder with a more durable one.
(This fix is also detailed on the MicrobeHunter.com forum here, if you are interested in the forum give-and-take)
Here it is, mounted in place:
The simple new holder is made from a piece of scrap 6061 aluminum. The only slightly 'critical' dimensions are 1 through 5:
1. The large hole; it is 0.250" (6.36mm), for a slip-fit over the existing pivot bushing (which has an O.D. of 0.250"). If you have trouble getting a slip-fit, try reaming out the hole a bit with the edges of the drill bit. When mounted in place, the joint between the bushing and the bar can be lubricated with a little oil.
2. The small hole; it is 1/8" (3.16mm), for a slip-fit of the 1/8" stainless rod (5/8" long, super-glued and tapped into the hole to protrude about 1/2" (12.7mm). This rod is where the cable wire loops over the holder, to work the filter in and out of the light path.
3. The distance between the holes: center-to-center is 1.16" (29.5mm). This dimension was gotten from the original plastic holder.
4. The bar thickness; this has to be less than the length of the existing pivot bushing, so that when tightening the bushing screw, the bushing is secured, but the bar is still free to pivot.
5. The semi-circular slot (groove) for the filter glass is about 3/32" (2mm) deep, cut with a round saw or abrasive blade using a hand-held rotary tool (Dremel or equivalent, in the US), and having a width of a little more than the thickness of the filter.
The overall length of the bar is arbitrary, mine was about 1.8" (46mm). The bar width was about 0.485" (12.3mm).
I added the washer over the inner end of the bushing to keep the bar from wobbling as much. This was due to using a too-large drill bit (0.253"); if a tighter slip-fit is achieved by using a 0.250" bit, the washer is not necessary.
The best way to find the position of where the groove needs to be cut is to mount the bar in place in the microscope, swing it down into position, and mark the bar with a dotted line (see above close-up of the bar) where the OD of the field condenser diffuser glass is, behind the bar. This will give you the best place for the filter, whether 26mm or 32mm. Then remove the bar and cut your groove, glue in the filter, etc.
The groove for the filter is filled with Hi-temp RTV, the edge of the filter is cleaned and smeared with the same, and the filter is bedded into the groove, and the whole thing propped up to keep the filter planar with the bar, until the RTV hardens:
To test the RTV, I ran the lamp for several hours with the scope baseplate screwed on, to see if the temperature would be a problem, or if the RTV would fail, etc. No problems; the RTV got harder, the temp of the bar got up to no more than 130F (oddly 300F on the diffuser glass). The RTV supposedly can take 700F. Tugging on the filter, the RTV seems strong enough, but I didn't pull it out of the groove, so am hoping for the best. In service it is under almost zero stress, so I think it should work OK over the long term.
It may seem that the bar blocks some of the light, since some of the filter is recessed into the groove, but the lamp is so close to the blue filter, that if one traces the light from the filament of the lamp to the edge of the diffuser, one can see that only the center 75% or so of the filter is used.
To help the positioning of the filter when swiveled into place, some sort of 'stop' can help. The microscope has a pin for this purpose, underneath in the base, right under the blue-filter control knob:
Friday, September 28, 2018
Manuals for old microscopes
One of the problems frequently vexing old-microscope enthusiasts like me is the lack of documentation, such as operating instructions, service manuals, exploded or circuit diagrams, etc.
Here are some links to pdfs of some hard-to-find old manuals. As new manuals are added, they will be edited into this post.
These manuals are free for use and printing hard-copies by anyone; also, please feel free to copy the files for free distribution from your own website. I strongly believe that these out-of-date manuals should be widely disseminated for free, for all to use.
******************************************************************
Here are some links to some of the larger on-line free collections of microscope manuals and catalogs for older microscopes (1930-2000):
Bausch and Lomb:
https://vademecummicroscope.com/bl-manuals-and-catalogues/
Leitz:
http://microscope.database.free.fr/Welcome.html
American Optical, Spencer, Reichert:
http://user.xmission.com/~psneeley/Personal/Microscope.htm
Polarizing microscopes:
http://earth2geologists.net/Microscopes/index.htm
Olympus:
http://www.alanwood.net/photography/olympus/downloads.html#bh
and Carl Hunsinger's excellent Olympus repair trove:
https://drive.google.com/file/d/0B7ckZ6amci3tcVdXdnFYVDJSRW8/view
Zeiss:
http://roslistonastronomy.uk/category/microscopy/equipment-for-microscopy/microscope-manuals
All sorts:
http://www.science-info.net/docs/
******************************************************************
Here is an English-language operating manual for the Reichert Univar, a 1970's-80's large, heavy, and sophisticated research microscope of its day. Reportedly, there were only about 300 of these made. I have one of these which I have been restoring to some semblance of its former glory. The manual was available on the internet only in German, so I translated it into English, reproduced it with all of its drawings, and also attached a Univar sales brochure to the end of the manual:
Reichert Univar Microscope Operating Instructions (English), V1.4:
https://drive.google.com/file/d/10DxbR9yXI4QQXK38fCUTFSXXXXo7vw6v/view?usp=sharing
-----------------------------------------------------------------------------------------------------------
Bausch and Lomb Dynazoom Bench Metallograph Instructions:
https://www.dropbox.com/s/2112ra92dk949kv/B%26L%20Bench%20Metallograph%20manual?dl=0
----------------------------------------------------------------------------------------------------------
Here are some links to pdfs of some hard-to-find old manuals. As new manuals are added, they will be edited into this post.
These manuals are free for use and printing hard-copies by anyone; also, please feel free to copy the files for free distribution from your own website. I strongly believe that these out-of-date manuals should be widely disseminated for free, for all to use.
******************************************************************
Here are some links to some of the larger on-line free collections of microscope manuals and catalogs for older microscopes (1930-2000):
Bausch and Lomb:
https://vademecummicroscope.com/bl-manuals-and-catalogues/
Leitz:
http://microscope.database.free.fr/Welcome.html
American Optical, Spencer, Reichert:
http://user.xmission.com/~psneeley/Personal/Microscope.htm
Polarizing microscopes:
http://earth2geologists.net/Microscopes/index.htm
Olympus:
http://www.alanwood.net/photography/olympus/downloads.html#bh
and Carl Hunsinger's excellent Olympus repair trove:
https://drive.google.com/file/d/0B7ckZ6amci3tcVdXdnFYVDJSRW8/view
Zeiss:
http://roslistonastronomy.uk/category/microscopy/equipment-for-microscopy/microscope-manuals
All sorts:
http://www.science-info.net/docs/
******************************************************************
INDIVIDUAL MICROSCOPE MANUALS
Here is an English-language operating manual for the Reichert Univar, a 1970's-80's large, heavy, and sophisticated research microscope of its day. Reportedly, there were only about 300 of these made. I have one of these which I have been restoring to some semblance of its former glory. The manual was available on the internet only in German, so I translated it into English, reproduced it with all of its drawings, and also attached a Univar sales brochure to the end of the manual:
Reichert Univar Microscope Operating Instructions (English), V1.4:
https://drive.google.com/file/d/10DxbR9yXI4QQXK38fCUTFSXXXXo7vw6v/view?usp=sharing
-----------------------------------------------------------------------------------------------------------
Bausch and Lomb Dynazoom Bench Metallograph Instructions:
https://www.dropbox.com/s/2112ra92dk949kv/B%26L%20Bench%20Metallograph%20manual?dl=0
----------------------------------------------------------------------------------------------------------
Tuesday, September 18, 2018
Bringing old microscopes back to life
One of my hobbies is rejuvenating old microscopes. Most of them are purchases via eBay, and are typically in rough shape and missing vital parts. I like fixing them up and restoring them to functionality. The vintages I concentrate on are from the 1950's to about 2000, at which point the used 'scopes become prohibitively expensive and remain contemporary laboratory resources.
Occasionally, I will sell a fixed-up microscope to a new owner. Some people may want or need a microscope, usually at home, for one reason or another: self-guided nature studies of the microscopic world around us (e.g., pond water), electronics repair, photo/video-micro/macrography, craft activities where magnification is desirable, and the all-important: helping to remove splinters from one's fingers.
I will post now and then on topics concerning microscope repair, collecting, and photomicrography, and will post some hopefully decent images of microscopic life, or other wonders that surround us but are not normally apparent.
For inspiration, information, and comraderie, I recommend the following highly interesting forums and websites: MicrobeHunter.com, microscopy-uk.org.uk, photomacrography.net, and quekett.org, to name some of the most prominent.
Occasionally, I will sell a fixed-up microscope to a new owner. Some people may want or need a microscope, usually at home, for one reason or another: self-guided nature studies of the microscopic world around us (e.g., pond water), electronics repair, photo/video-micro/macrography, craft activities where magnification is desirable, and the all-important: helping to remove splinters from one's fingers.
I will post now and then on topics concerning microscope repair, collecting, and photomicrography, and will post some hopefully decent images of microscopic life, or other wonders that surround us but are not normally apparent.
For inspiration, information, and comraderie, I recommend the following highly interesting forums and websites: MicrobeHunter.com, microscopy-uk.org.uk, photomacrography.net, and quekett.org, to name some of the most prominent.
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