Dear Lukasz,

if you would like/must adhere to the manufacturers’ cleaning instructions (which also can be found on

http://www.microstartech.com/index/diamondknives/diamondmanual.htm) you only have the alternative between i) distilled water and ii) perhaps ethanol. There is no restriction within the text of the cleaning instructions for ethanol. I suggest to use 50 or 70% EtOH. If you cannot buy the “Diamond knife cleaner” any more (I guess the apparatus did not pay its costs by purchasers) you easily could make one yourself (beaker glass, some small construction on “4 feet” made from plastic to leave the central space for a magnetic stirrer, as well as with a platform to fix the knife on that in a safe position above the magnetic stirrer. I wouldn’t think over / worry about the switching of direction the magnetic stirrer in the “Diamond knife cleaner”…. over night stirring in one direction IMHO would suffice to get any dirt from the knife edge, I guess. If you don’t have a diamond knife “wetting agent” you should know that before the advent of such agent everybody used only his own spittle (ok, I know this might not be a good word) or therefore, better: saliva in water. Afterwards washing with A. bidest several minute/and several times should be sufficient. As you say you use for your Diatome knife/knives the cleaning technique “wiping” orthogonally the knife ege with a cuspidal polystyrene foam stick (in former times sticks made from elder pith were provided) you should know that in my hands – if properly done and the facet of the foam stick is clean and does not contain – this cleaning did not destroy a knife edge for more than two years of knife use.

Otherway round one could say that the diamond MicroStar uses in their knives may be prone to cleaning overload (this possibility only as a logical conclusion). Saying this, it is clear that

i) no force or heavy pressure must be applied with the foam stick,

ii) the compression unto the knifes’ cutting edge must be set without any lateral deviation,

iii) skimming over the cutting edge only in one direction, using another position on the stick bevel every time as the last skimming mark, and,

iv) that razor blades should be not only fresh but also cleaned thorougly by releasing adhering dust particles and – much underestimated – traces of oil /fat initially applied to the razor blades after production (e.g. Gilette blades) for preventing them from rusting/oxidizing over time.

If one is not careful with that latter procedure more dust or even hard fibres from paper towel used for defatting can be applied to the polystyrene foam fase / bevel which indeed could kill the knife edge. Last point: if dry your knife with the water trough with compressed air/ or clean canned gas keep in mind that in house installed compressed air systems with nozzles (compressed air pistol) can damage your knife edge too if the compressed air stream has not been filtered prior to discharge (Cave: oil microdrops as well as particulate matter eventually from rust within metallic pressure tubes) and the airflush is too intensive (reduce pressure to lower than 1 bar) or is applied not virtually orthogonal to the knife cutting edge.

Best wishes and regards, Wolfgang

Dear Lukasz,

if you would like/must adhere to the manufacturers’ cleaning instructions (which also can be found on

http://www.microstartech.com/index/diamondknives/diamondmanual.htm) you only have the alternative between i) distilled water and ii) perhaps ethanol. There is no restriction within the text of the cleaning instructions for ethanol. I suggest to use 50 or 70% EtOH. If you cannot buy the “Diamond knife cleaner” any more (I guess the apparatus did not pay its costs by purchasers) you easily could make one yourself (beaker glass, some small construction on “4 feet” made from plastic to leave the central space for a magnetic stirrer, as well as with a platform to fix the knife on that in a safe position above the magnetic stirrer. I wouldn’t think over / worry about the switching of direction the magnetic stirrer in the “Diamond knife cleaner”…. over night stirring in one direction IMHO would suffice to get any dirt from the knife edge, I guess. If you don’t have a diamond knife “wetting agent” you should know that before the advent of such agent everybody used only his own spittle (ok, I know this might not be a good word) or therefore, better: saliva in water. Afterwards washing with A. bidest several minute/and several times should be sufficient. As you say you use for your Diatome knife/knives the cleaning technique “wiping” orthogonally the knife ege with a cuspidal polystyrene foam stick (in former times sticks made from elder pith were provided) you should know that in my hands – if properly done and the facet of the foam stick is clean and does not contain – this cleaning did not destroy a knife edge for more than two years of knife use.

Otherway round one could say that the diamond MicroStar uses in their knives may be prone to cleaning overload (this possibility only as a logical conclusion). Saying this, it is clear that

i) no force or heavy pressure must be applied with the foam stick,

ii) the compression unto the knifes’ cutting edge must be set without any lateral deviation,

iii) skimming over the cutting edge only in one direction, using another position on the stick bevel every time as the last skimming mark, and,

iv) that razor blades should be not only fresh but also cleaned thorougly by releasing adhering dust particles and – much underestimated – traces of oil /fat initially applied to the razor blades after production (e.g. Gilette blades) for preventing them from rusting/oxidizing over time.

If one is not careful with that latter procedure more dust or even hard fibres from paper towel used for defatting can be applied to the polystyrene foam fase / bevel which indeed could kill the knife edge. Last point: if dry your knife with the water trough with compressed air/ or clean canned gas keep in mind that in house installed compressed air systems with nozzles (compressed air pistol) can damage your knife edge too if the compressed air stream has not been filtered prior to discharge (Cave: oil microdrops as well as particulate matter eventually from rust within metallic pressure tubes) and the airflush is too intensive (reduce pressure to lower than 1 bar) or is applied not virtually orthogonal to the knife cutting edge.

Best wishes and regards, Wolfgang

Dear Lukasz, dear Sarah,

I have to add the following to my former post:

i) if you use polystyrene sticks for your Diatome knives/knife, it is essential that the tip with the chiseled edge at 45°degrees must not be used dry, i.e. always moisten with fluid (distilled water, Ethanol) or

ii) detergent solution of 0.1 % Triton solution.

Soaking in the solutions will be often sufficient.

Best regards,

Wolfgang

the best way to clean diamond is a strongly oxidizing solution of H2SO4 HClO4 and HNO3... but only for diamond, if there are some metallic part, it is not indicated!

Hello- Wolfgang's answer is entirely correct. I do essentially what he has described; using carefully trimmed and cleaned polystyrene sticks, typically provided by Diatome with new/resharpened knives. I can make a stick last for a long time (years) by cutting off a tiny wedge and holding it with self-closing forceps. For my very sensitive knives I conduct the cleaning under a dissecting microscope, usually after soaking the knife in distilled water for an hour or so. I use only water to clean the blade itself (as Wolfgang described) then I use ethanol and a fresh polystyrene wedge to clean the front face of the diamond, without contacting the blade edge. This ensures a clean surface for sections to "slide" down, which is particularly critical for cryosectioning but helpful for ambient sectioning as well. Good luck! ---Mark

Dear Lukasz,

for my diamond knife I use two methods: in the first method I use trimmed and cleaned polystyrene sticks as Mark said to you. In the second method (that I use always without any problem) I use sticks of Balsa; I trim the stick with an angle of 45° than i put in MilliQ water so the wood became soft and I can clean the knife

best regards

Simone

Thank You very much for Your's answers - they're very useful!

Best regards,

Lukasz

Dear Lukasz,

you're welcome,

should you have any further question, please post.

Best regards,

Wolfgang

We never touched anything to the diamond. Never let it dry out while sectioning (no long lunch breaks). New sectioning should clean off any debris. If plastic is poorly cured, stop-- don't muck up the blade. When finished, lift out carefully with the trough full, then over a beaker or tray take a squeeze water bottle filled with dilute detergent and spray a steady stream into the trough guiding upward over the edge (downward up), Repeat from the back (from bottom of blade to top. Then rinse both sides in the same manner with a narrow stream from a squeeze bottle of distilled water, then briefly with 75% ethanol and finally 100%. Blast out any residual with a pressurized air can to displace any fluid left. If there is any possibilty that dust or grit may have gotten into the box or on the knife between each use, clean before using.

General cleanliness during use is expected-- not letting errant sections get lost, maintaining a clean, dust-free environment. In emergencies we did not use soft wood but rather sturdy orangewood sticks cut at a narrow angle with a sharp blade-- not leaving microscopic wood spinters anywhere around the diamond is important.

Regarding the cleaner no longer available-- they probably had an MSDS (Material Safety Data Sheet) listing of the composition-- why not look for it? Or ask them what it was made of, and make your own.

Avoid buying diamond knives from manufacturers that do not know how and cannot help. It used to be that that would reshape the knives if they are serious sellers.

Dear all,

with respect to the "Cleaner" (which - to be exact ! - is a special magnetic stirrer device) mentioned in two or three posts I would like to point you to:

http://www.2mstrumenti.com/upload/taab/Microtomy%20&%20Histology%20Part%202.pdf

From TAAB_ http://www.taab.co.uk/

Phone: +44 (0) 118 981 7775 Fax: +44 (0) 118 981 7881

e-mail: [email protected] www.taab.co.uk

where eventually one can ask if there is one such specific stirer device in stock for sale. The pdf shows:

MICROTOMY & HISTOLOGY: cf. page 12.14:

@Jacques: MicroStar Tech's Website: http://www.microstartech.com, in their fact sheet / application note at http://www.microstartech.com/index/diamondknives/diamondmanual.htm they state that IF a knife can't be cleaned by the user, they will do it for the client for free (except paying postage&handling).

Regards,

Wolfgang

DISCLAIMER: no affiliation with MicroStarTech or any other firm/company mentioned, no financial interest, just long time user of diamond knives of another famous brand.