Thread: advanced strop paste making

I recently brought ha 1 Mic diamond spray and a crox semi paste and both seem to be alcohol based and dry quickly and cleanly. I also got some .3 Mic alumina 'A' powder which I've tried to make a paste with. I used neats foot oil for this but the powder doesn't dissolve into the oil and stays seperated for the most part. I would like to make an paste more like the crox I have and am wondering if anyone has advise on this or how to get the alumina to dissolve in the oil. Cheers for you help. Ed

Maybe try dish washing detergent

I read a post by Keith of Hand American that said that finer particles do not have the mass to mix with the carrier too well, and he advised putting some BB shot in the bottle to help stir things up when you shake it.

Glycerine is another carrier you might want to try - haven't tried it myself, I must add.

Regards,
Neil

Cheers for your replys. have tried mixing with alcohol/oil mixes but still remaining separate. Will try suggestions a see how it goes.

Glycerin and crox don't mix... or they do but it can spontaneous combust or even explode!

Originally Posted by Lemur

Glycerin and crox don't mix... or they do but it can spontaneous combust or even explode!

I'm not at all sure about that!

Most modern explosives use a nitric base - that's why nitric acid (plus sulphuric acid) is used in the formulation nitro-glycerin; in other words the glycerin must be nitrated.

Chromium oxide is used in the making of thermite (a non explosive mixture that glows brightly at an intense heat - the 'Goldschmidt' reaction) but this has aluminium in it - the aluminium is oxidised by the oxide in chromium oxide.

Green chromium oxide and glycerin are used to make green soap - don't hear of many people being blown-up in the baths!

Regards,
Neil

Just to clarify. Should i mix alumina oxide and glycerine i won't blow up the shed will i. Alcohol(pure99.9%) also being used in some tries to get this alumina to make a paste.

Haha, no, I didn't make it up, check the MSDS for Chromium Oxide and see for your self,
Glycerin and Glycerol is the same, just different names for it.
I can by some strange reason not open any PDF right now, so can't find a good link, sorry!

Thermite is normally made with Iron Oxide and Aluminum powder, no Chromium in a normal mixture of that.
CrO does give off Oxygen like AlO but the reaction would be to fast for any practical use of the Thermite.
(My field of work in the Army was explosives, been teaching about them. A little C4, knocking at your door!)

Edit; fixed the PDF mess, here's a link; http://www.sciencelab.com/msds.php?msdsId=9923471
Check under "Section 5: Fire and Explosion Data" it says; "Special Remarks on Explosion Hazards: Contact between glycerol and Chromium oxide may produce explosion."

Originally Posted by eddy79

Just to clarify. Should i mix alumina oxide and glycerine i won't blow up the shed will i. Alcohol(pure99.9%) also being used in some tries to get this alumina to make a paste.

It's safe, with Chromium Oxide there is a risk mixing with Glycerol, it may not be high but it sure is one!

Surely the reaction can only take place with chromium(VI)oxide (CrO3) - the brown compound, otherwise known as chromic acid and chromium tri-oxide. This type is cancer-inducing, very toxic and corrosive. It is a powerful oxidiser, igniting stuff like glycerol and ethanol.

Chromium(III)oxide (Cr2O3) is the green pigment we are familiar with. It is fairly stable - even if used with aluminium to make a thermite reaction it does not explode, produces little or no sparks, an no smoke - it just glows brightly.