Doing Diatoms a Different Way

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Charles
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Re: Doing Diatoms a Different Way

#151 Post by Charles » Thu Mar 01, 2018 5:07 pm

You're welcome JWW.

Kurt, it's actually much better and smoother when I don't have to squint down one tube. Because when I swing the photo port in, it blacks out the left eyepiece, which makes it hard to judge depth of view and targeting.

Yes, I have been making some permanent type slides too. Still trying to get it fine tuned where they don't go wandering around the cover glass when I heat it.

Hobbyst46
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Re: Doing Diatoms a Different Way

#152 Post by Hobbyst46 » Thu Mar 01, 2018 7:13 pm

Very impressive accomplishment!

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Re: Doing Diatoms a Different Way

#153 Post by Charles » Fri Mar 02, 2018 11:54 am

Thank you Doron.

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KurtM
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Re: Doing Diatoms a Different Way

#154 Post by KurtM » Fri Mar 02, 2018 2:20 pm

Charles wrote:Still trying to get it fine tuned where they don't go wandering around the cover glass when I heat it.
I know exactly what you mean, and would be extremely interested in hearing how you manage it...
Cheers,
Kurt Maurer
League City, Texas
email: ngc704(at)gmail(dot)com
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Re: Doing Diatoms a Different Way

#155 Post by Charles » Mon Mar 05, 2018 7:54 pm

Working on it Kurt and will post results.

In conjunction, I'm trying to figure the best way to raise the coverslip on large or fragile diatoms, so they won't be crushed. I've heard of rings being used as well as using pieces of broken coverslips on the corners to keep the coverslip raise. I've come upon a solution to use small hollow circular tubing so I can 'stamp' out disks out of thin aluminum sheeting. The aluminum is no problem. I just use an old disposable pie tin. The problem is finding very small hollow tubes. Then as I was looking at my micro-manipulator and hypodermic needle attached, I realized I can use a hypodermic needle to stamp out my disks. I have found that you can't just use the needle as they come with the beveled point as it just pushes the aluminum aside and no usable disks. A long time ago I ordered a bag of assorted sized hypodermic needles with their ends clipped for use in holding the pulled capillary glass needles I use in the micro-manipulator. It has various sizes and I started punching out disks. I put the pie tin on top of a piece of cardboard and then push the needle into the pie tin. and a circle of aluminum is pushed out onto or into the cardboard. I started with the largest gauge needle and ended with the smallest. They all punched out a fairly round disk of aluminum but I'm thinking the very smallest will do.

Pictures to follow.
Last edited by Charles on Mon Mar 05, 2018 9:02 pm, edited 1 time in total.

Hobbyst46
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Re: Doing Diatoms a Different Way

#156 Post by Hobbyst46 » Mon Mar 05, 2018 8:36 pm

Charles
Those tin aluminum "washers" are really a very good idea, if you can make them absolutely flat, and if the the mounting medium is chemically neutral.

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Re: Doing Diatoms a Different Way

#157 Post by Charles » Mon Mar 05, 2018 9:06 pm

They are not washer shaped but more of a small plug of circular aluminum to put at the corners of the coverslip, like posts holding up a roof. If they were washer shaped the mountant fumes and bubbles would be trapped instead of escaping out from under the coverslip when heated. The mounting medium is neutral so shouldn't be a problem. I'll post some pictures later.

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Re: Doing Diatoms a Different Way

#158 Post by Charles » Mon Mar 05, 2018 9:37 pm

Here is the aluminum pie tin, cardboard backing and hypo needles with clipped ends.
Pie Tin and Needles.jpg
Pie Tin and Needles.jpg (86.42 KiB) Viewed 12706 times
And the resulting aluminum spacers.
Spacer discs.jpg
Spacer discs.jpg (81.04 KiB) Viewed 12705 times
And here they are on the edge of a 18mm dia coverslip to show size in relationship to coverslip.
Spacer discs along coverslip.jpg
Spacer discs along coverslip.jpg (58.51 KiB) Viewed 12704 times

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KurtM
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Re: Doing Diatoms a Different Way

#159 Post by KurtM » Tue Mar 06, 2018 4:20 am

I guess this means radiolaria are sufficiently structurally robust to hold the cover slip at bay without assistance, interesting. What diatom forms are you working with that necessitate this?
Cheers,
Kurt Maurer
League City, Texas
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Charles
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Re: Doing Diatoms a Different Way

#160 Post by Charles » Tue Mar 06, 2018 11:33 pm

I have quite a few diatoms which are large (like the Isthmia in the last video), have projections (like Kittonia and Stephanopyxis) or are delicate and I don't want to crush them. I remember Rod had those long strands of Ellerbeckia which were crushed by the mountant and cover glass.

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Re: Doing Diatoms a Different Way

#161 Post by Charles » Mon Jun 11, 2018 3:49 pm

Just updated my setup:
B&L StereoZoom 7 with 15X eyepieces, 1.5X auxiliary lens which now gives me 157X max magnification.

I finally found the 1.5X B&L auxiliary lens for a reasonable price. The addition of the 1.5X auxiliary lens and extra 52X magnification really makes a difference checking out smaller diatoms for damage and I still have plenty of working distance for my micromanipulators. I also have the 2X auxiliary lens, but found it did not give me enough working distance. Now if I could only get use to using the 20X eyepieces, I could get the magnification up to 210X but I think 157X is the sweet spot for this purpose.
B&L+SZ7+with+Canon+Camera+and+Prior+Micromanipulator.jpg
B&L+SZ7+with+Canon+Camera+and+Prior+Micromanipulator.jpg (133.35 KiB) Viewed 12514 times

Hobbyst46
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Re: Doing Diatoms a Different Way

#162 Post by Hobbyst46 » Mon Jun 11, 2018 5:47 pm

@Charles
Since I have neither the skill nor the ambition to pick out and arrange diatoms, I only look forward to the day when you start selling some of your creations!

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Re: Doing Diatoms a Different Way

#163 Post by Charles » Mon Jun 11, 2018 8:49 pm

I haven't sold any as of yet but I have sent some prepared slides of diatoms to people in exchange for sample material they have sent me from overseas. I make them type slides from the sample they send me.

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Re: Doing Diatoms a Different Way

#164 Post by JackyMac » Mon Jun 11, 2018 10:15 pm

Drawing glass needles.

I use soda glass melting point capillaries - they have a low melting point.
And I use an ordinary paraffin wax tealight. The capillary gets a bit sooty, but you can wipe that off.

As long as you keep twiddling the tube and gently tugging until it gives in the right way, you don't risk burning you fingers. With practice you can pull thick, thin, wispy capillaries, whatever you're after. And it's a very simple setup - no spirit to spill.

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Re: Doing Diatoms a Different Way

#165 Post by Charles » Tue Jun 12, 2018 12:36 am

Welcome Jacky! Good you made it over here!

I use capillary tubes over an alcohol burner with no soot. I would probably break my tips trying to clean the off.

I have a system where I twist and work the capillary tube over the flame until I have a solid middle and then do the pull as I'm coming off the flame. It gives a nice faint snap when it pulls apart with a solid needle on both ends. I find if I don't twist and work it some in the heat to get it solid, I may end up with a nice needle but it is hollow and if the tip breaks off, it just sucks up moisture and debris makes for a messy needle after a while. With the solid needle, the tip may break off but I still have a workable needle for a while. I like my needles solid, stout with a nice point. You can see from this video the perfect needle...at least for me. It is heavy enough to pick up very large diatoms where the point is small enough to pick up the smallest diatom:
https://www.youtube.com/watch?v=g-F0Id_ ... e=youtu.be

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75RR
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Re: Doing Diatoms a Different Way

#166 Post by 75RR » Tue Jun 12, 2018 5:04 am

Hi Charles
Was wondering how thin your needles are?
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Re: Doing Diatoms a Different Way

#167 Post by Charles » Tue Jun 12, 2018 9:21 pm

The needles are drawn from 5mm long x 1mm diameter capillary tubes so they end up about 3mm long and the last 1mm tappers down to a point. So if I do it right I get two needles from one capillary tube.

Here is a photo of the capillary tubes, the pulled needles in a plastic divided petri dish and on a 21 gauge needle with the point clipped off. The needle fits nicely into the end of the capillary tubes and I put a drop of sugar water to secure the needle in the tube.
Pulled Needles.jpg
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75RR
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Re: Doing Diatoms a Different Way

#168 Post by 75RR » Wed Jun 13, 2018 5:07 am

Thanks Charles
When you have pulled the 1mm diameter glass capillary ... how many µm wide is the tip on average.
Zeiss Standard WL (somewhat fashion challenged) & Wild M8
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Re: Doing Diatoms a Different Way

#169 Post by Charles » Wed Jun 13, 2018 10:59 am

The tip would vary in size depending on how it is pulled. Most of mine are less the half a micron, but if you get them too thin, they are too wispy for use. I do make some which are about 1 micron, to move large diatoms which have stuck to the slide during drying.

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Re: Doing Diatoms a Different Way

#170 Post by 75RR » Wed Jun 13, 2018 11:02 am

That is amazingly small. Had been wondering if it were possible to get down to 10µm diameter. Now I know. Many thanks!
Zeiss Standard WL (somewhat fashion challenged) & Wild M8
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Re: Doing Diatoms a Different Way

#171 Post by JackyMac » Thu Jun 21, 2018 8:32 pm

Kemp adhesive
Right. I have spent the afternoon making my own poor pot of ' Kemp adhesive'. for my diatoms.
The recipes given were a bit open ended.
I have determined that:
  • make a thick syrup of Gum Tragacanth at high temperature- see below.
    using equal volumes of hot Gum Tragacanth syrup, IPA and Glycerine - combine.
    Add a few drops of Glacial acetic acid combine until a uniform mixture is obtained
will hopefully give me a decent adhesive.

Aside: when I was a Girl Guide in 195* I had an issue passing my 'Cooks Badge' because I made lumpy custard.
Dissolving/mobilising Gum Tragacanth actually gave me similar problems.

The recipe(Formula) given somewhere earier in this thread failed to mention the ratio of Gum Tragacanth powder to the water- It is NOT w/v. I used far too much powder and had to keep adding water until it looked like lumpy wallpaper paste even though I boiled and stiirred the mixture for ages. Hence I decided that it meant 1/3 Gum Tragacanth syrup.
Filter and wallpaper paste really don't belong in the same sentence a tea-strainer may have some place in eliminating lumps, but a filter paper is a waste of time and resources.

Back to my aside about custard - if you add hot liquid to custard powder you WILL end up with lumpy custard - I know about this,
The deal is mobilise the powder with a lttle cold water before you pour on the boiling liquid, When you do that stir like crazy and you will end up with silky smooth custard. I have a feeling this is the path I should have taken with the Gum Trag.
The ratio is based on liquid elements 1/3;1/3;1/3 so make up a saturated syrup first using however much (not much_ GT powder) you need to give you an appropriate quantity of thick syrup.

Then follow through the recipe.

To me it is comforting that all of the ingredients can be found in an adventurous cook's kitchen, especially if they have made fondant icing. Hence cleaning up up and disposal of residues is Just the ' wipe off with kitchen paper, then wash in copious hot water and detergent', Not like making algal balls where if you put the CacCl2 and alginate down the same sump you will be taking the 'U-bend' apart

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Re: Doing Diatoms a Different Way

#172 Post by Hobbyst46 » Thu Jun 21, 2018 8:55 pm

@JackyMac

The same rule holds for gelatin (for Bavarian Cream). Always mix it first with cold water, later on switch to hot water.

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Re: Doing Diatoms a Different Way

#173 Post by Charles » Thu Jun 21, 2018 9:35 pm

The Gum Tragacanth should be a finely ground powder. You stir in small amounts of the Gum Tragacanth to the 30ml of water until it is syrupy. You can take it off the heat and then stirring in the glycerin and alcohol will make the adhesive very liquid and can be filtered after stirring in the glacial acidic acid.

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Re: Doing Diatoms a Different Way

#174 Post by KurtM » Fri Jun 22, 2018 12:50 am

Hey Charles, did you ever figure out how to cure arranged slides without the valves wandering around?
Cheers,
Kurt Maurer
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Re: Doing Diatoms a Different Way

#175 Post by Charles » Fri Jun 29, 2018 12:45 am

Hi Kurt,

Not exactly. The amount of adhesive seems to be the key. But I find when I use small 'flat' diatoms, they will stay in place but when I use large 'thick' diatoms they tend to float around more. :(

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Re: Doing Diatoms a Different Way

#176 Post by keithstout » Sat May 09, 2020 9:48 pm

Charles wrote:
Fri Dec 09, 2016 11:51 pm
Charles wrote:
KurtM wrote:I want to know about the adhesive. I've fooled around with arranging some, but hit a wall when it comes to putting them down as desired, and getting them to stick. But even if I were to get an arrangement successfully placed, I still have no idea how I'd cure Pleurax without the bubbling undoing the arrangement.

So yeah, you have a bunch of us stirred up pretty well with your post, I'd say. 8-) :lol:
I use an adhesive which Klaus Kemp uses. It is made of 1/3 finely ground gum tragacanth dissolved in 1/3 distilled water and 1/3 IPA with few drops of glacial acetic acid added after.

They say the key to keep the forms from moving is proper adhesive and gentle heating.
Looking at my notes from 2012, it looks like I left a key ingredient out of the above adhesive...Glycerin.
The recipe for the adhesive is as follows.

This is best done with a heater with a magnetic stirrer and your mixing beaker should be in a larger beaker or container of water to prevent scorching.

-Boil 20ml of water (the amount can be 30ml or whatever you want as long as you use equal amounts of Glycerin and IPA. Believe me, 50-60ml of this will last you a lifetime) in a beaker with magnetic stirrer rod in place.
-Activate the stirrer and slowly add the Gum tragacanth until the mixture is the consistency of heavy syrup.
-Turn off the heat.
-Add 20ml of Glycerin (the stirrer should still be going)
-Add 20ml of IPA (90% and the stirrer should be still mixing)
-Add 3-4 drops of Glacial Acetic acid.
-Let all ingredients mix well.
-Filter the mixture into a clean storage container.
Hello, Charles. I'm a beginner diatom herder. I'm ready to develop my mounting skills. Going through this recipe, I see the compound called IPA, 90%. Is that isopropyl alcohol? Also, can you provide a link of the supplier from which you get these chemicals? I'd be so grateful. Keith.

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Re: Doing Diatoms a Different Way

#177 Post by Charles » Sun May 10, 2020 2:32 am

Hi Keith,
IPA is isopropyl alcohol and along with glycerin can be bought in Drug stores. The Gum tragacanth and Glacial Acetic acid I got online on Amazon or eBay.

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Re: Doing Diatoms a Different Way

#178 Post by keithstout » Sun May 10, 2020 3:10 am

Smashing! I got some. I didn't think eBay sold that kind of stuff and assumed you had a line on some kind of laboratory chemical supply. I go hunting at the drug store tomorrow for IPA and glycerin. I really appreciate the info. Is the hand stirring of the adhesive making process especially laborious that one ought to consider a magnetic stirrer?

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Re: Doing Diatoms a Different Way

#179 Post by Charles » Sun May 10, 2020 1:42 pm

A magnetic stirrer isn't necessary, just helpful. You can stir with a spoon, fork or anything handy. Just make sure to double boiler it and don't let it get too hot and scorch. Filtering will get the lumps out.

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Re: Doing Diatoms a Different Way

#180 Post by keithstout » Sun May 10, 2020 7:05 pm

OK, got it.

But whoa, whoa, wait just a minute. There's a problem here...maybe. Consider the mountant: it must be formulated with a proper index of refraction to support image quality of the microscope. Anything in the light path must. Does this adhesive have the proper index of refraction? I can't find any mention of that.

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