Author Topic: Polished electrodes...  (Read 5411 times)

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Re: Polished electrodes...
« Reply #16 on: March 08, 2016, 22:05:38 pm »
today i worked into the polishing by sand paper trying to find the best methode to do it.. .

i found that is better to start rounding the ends of the tubes inwards and outwards.. take out any sharp points...

later is good to do one time on the outside of the tube a first polishing to understand how is to polish inside..

outside of the tubes however the surface has some defect from the manufacture process Trefilating the tubes to bring them to right diameter is accomplished by having a initially larger diameter tube than  roling it with some hard and heavy rollers so its possible to get a small diameter seamless tube...

so outside of the tube the surface is plenty of defects to take it out i did the following
)
first sand the tube in the vertical lenght direction perpendicular to the defects ( risks.). / than tangencial follwoing the circunference of the tube..

i fixed my tube to a piece of wood rod half cut in half where i can fix it over some sandpaper and attach it to my driller so i can mak the tube turns and i can polish in the outer circunference with easy when the tube is stuck,,and polish the internal if is allowed to slip

i used 80 than 150 for iron sandpapers than 360 and 600 water sandpapers aways doing in bothe directions..stop in one direction and turning in the other of course;;; this makes it easier..

after it i used a piece of cloth and polishing mass number 2 for cars.. and also did in both directions..

you will see that this last step is decisive in geting mirror like surface...

once outside is mirror the inside will be easier.. .

i used 600 sandpaper inside, than polishing mass and cloth on turning...than inserting the turning thing into the tube to polish inside..








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Re: Polished electrodes...
« Reply #17 on: March 08, 2016, 22:13:01 pm »
Theoreticaly i believe the more the surface is flat the higher will be the voltage we are able to apply across the water capacitor since it will be harder for a single point to oxidize... or liberate an ion..

when one point in stailess steel oxidize it become an anode and will develop a current in reference to the rest of the piece that acts as a cathode so it never stop increasing the corrosion the oxided point...

is the same as having two dissimilar metals you get a battery effect...so it corrode untill there is chemicals to react.;;;

My electrodes are now very flat it apear to me that is the way to go for it...

the conditioniong may be than to use some kind of nitric acid and or citric acid solution intercallating with a chloride solution to take the oxides layer and allow electropolish to make an even surface..

if we apply some kind of polishing wax some kind of films can be formed too but this would not be stable i guess and so actually would be better to have only a passivated surface



« Last Edit: March 08, 2016, 23:43:30 pm by sebosfato »

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Re: Polished electrodes...
« Reply #18 on: March 08, 2016, 23:29:51 pm »

you can put some dish wash liquid in water , it helps clean the sand paper

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Re: Polished electrodes...
« Reply #19 on: March 09, 2016, 00:51:54 am »
yes massive i forgot to mention the cleaning at each step and that the electrodes should not get hot i keep a bootle of water diping to maintain it cold..

if it heats up other metals arrise in the surface ....

is a very slow process

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Re: Polished electrodes...
« Reply #20 on: March 12, 2016, 23:55:12 pm »
the electrodes gap now seems much bigger although the actuall size didnt change more than 0.1mm

as the borders of the tubes and rods are round its possible to see it beter inside the gap...

today i further polished the tubes now i tried again with car polishing and wax for polishing..

i´m certain that is not the best aproach but it the only thing i could find about it yet..

i´m feeling to do the right thing but feel like its the wrong process or materials.. .otherwise i believe it should be done already... monday i will get some time probably will take to somewhere give a professional polishing,,,better than my eyes can do...
 
from what i see it does not mather how much i go after all i never get the mirror like evenly inside the tube...

PS stanley meyer tubes seem to have absolutely no corrosion spots.. seems perfectly passivated...

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thermic treatment
« Reply #21 on: March 21, 2016, 14:41:42 pm »
how about thermic treatment?

temper? anybody tried ?

from wiki Quenching[edit]
Main article: Quenching
Quenching is a process of cooling a metal at a rapid rate. This is most often done to produce a martensite transformation. In ferrous alloys, this will often produce a harder metal, while non-ferrous alloys will usually become softer than normal.

To harden by quenching, a metal (usually steel or cast iron) must be heated above the upper critical temperature and then quickly cooled. Depending on the alloy and other considerations (such as concern for maximum hardness vs. cracking and distortion), cooling may be done with forced air or other gases, (such as nitrogen). Liquids may be used, due to their better thermal conductivity, such as oil, water, a polymer dissolved in water, or a brine. Upon being rapidly cooled, a portion of austenite (dependent on alloy composition) will transform to martensite, a hard, brittle crystalline structure. The quenched hardness of a metal depends on its chemical composition and quenching method. Cooling speeds, from fastest to slowest, go from fresh water, brine, polymer (i.e. mixtures of water + glycol polymers), oil, and forced air. However, quenching a certain steel too fast can result in cracking, which is why high-tensile steels such as AISI 4140 should be quenched in oil, tool steels such as ISO 1.2767 or H13 hot work tool steel should be quenched in forced air, and low alloy or medium-tensile steels such as XK1320 or AISI 1040 should be quenched in brine.

However, most non-ferrous metals, like alloys of copper, aluminum, or nickel, and some high alloy steels such as austenitic stainless steel (304, 316), produce an opposite effect when these are quenched: they soften. Austenitic stainless steels must be quenched to become fully corrosion resistant, as they work-harden significantly.[18]

Tempering[edit]
Main article: Tempering (metallurgy)
Untempered martensitic steel, while very hard, is too brittle to be useful for most applications. A method for alleviating this problem is called tempering. Most applications require that quenched parts be tempered. Tempering consists of heating steel below the lower critical temperature, (often from 400 to 1105 ˚F or 205 to 595 ˚C, depending on the desired results), to impart some toughness. Higher tempering temperatures (may be up to 1,300 ˚F or 700 ˚C, depending on the alloy and application) are sometimes used to impart further ductility, although some yield strength is lost.

Tempering may also be performed on normalized steels. Other methods of tempering consist of quenching to a specific temperature, which is above the martensite start temperature, and then holding it there until pure bainite can form or internal stresses can be relieved. These include austempering and martempering.[18]

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Re: Polished electrodes...
« Reply #22 on: March 22, 2016, 02:29:06 am »
I think maybe passivation is the only way with stailess steel

dany danfor said that 304 would not work and it had to be 410 or 430 if i remember well

this ferritic steel can receive heat treatment and quenching to harden

the 304 needs to be cold worked apparently trefilating may be an option..

it seem to me that 304 is very soft on the rod but very hard on the tubes because probably the tubes are cold trefilated or something to get this sizes...

i mean that is easy to get it damaged like if it was very soft metal...

my electrodes were pited from my 11 cell cavity today i took the out to look

this week i willbe cleaning it again and polishing but this time i will get it passivated very well before try

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Re: Polished electrodes...
« Reply #23 on: March 22, 2016, 13:56:41 pm »
Not sure if Dan Danford said this, to be honest...

I worked with magnetic ss 430 in my magnetic cell...