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done rust electrolysis??? ...gota few ?'s for ya.

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timbn2

timbn2

Jedi Hopeful
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I'm using a 12v/25 amp rectifier similar to the one sold by Caswell. I have 6 pieces of rebar around a 5 gal bucket all wired together with copper wire. i have the red lead on that and the black lead on the part... or more precisely to copper wire wrapped around the part. I used 1/2-1/3 cup arm and hammer WASHING soda in water as the electrolyte fluid.
i tried 2 different small parts (brake master cylinder) and a 1/2" rod ranging form 15 min to 2 hours on 8-12 volts. the most amps i ever got at the highest volt setting was 5. Does that sound right, or should i be getting more amperage at 12 volts?
also regardless of the time, there didn't seem to be a whole lot of rust removed on either part. the water definatly had rust in it and so did the re-bar and the part was "bubbling" like its supposed to.
The master cyl. only had a very small amount of rust on it and it still had some on it after about 1 hr.

Did i do anything wrong? Do i just need to leave my parts for more time? I am also told that as soon as the part is de-rusted the reaction will stop despite current flow. is this true?

thanks a lot!
 
Re: done rust electrolysis??? ...gota few ?'s for

Tim,

There is a thread on this over in the Tools section so you might be able to gleen some info from that or ask the wider audience for help. Someone mentioned just using vinegar as a rust remover .. sounds easier than the electrolysis method.

Personally, I use glass bead blasting and diluted muriatic acid (if necessary) to de-rust parts. For the master cylinder, if it needs to be re-sleeved, just let the vendor blast it for you. /bcforum/images/%%GRAEMLIN_URL%%/grin.gif (I used https://www.brakecylinder.com/ )

Cheers,
John
 
Re: done rust electrolysis??? ...gota few ?'s for

John,
Excellent link...thank you! i may just use them!! one other question... where do you get your beads for your bread blaster? i have a cabinet with sand right now, but might like to try the bead route.
thanks
tim
 
Re: done rust electrolysis??? ...gota few ?'s for

I bought the glass beads at Harbor Freight (same place I got my 'table top' blaster). I have also used sand which does work better for heavier rust/paint and use the glass beads for finer cleanup. Just be careful if/when you spill any glass beads .. they are very slippery on concrete!

Cheers,
John
 
Re: done rust electrolysis??? ...gota few ?'s for

I have found that electrolytic rust removal works very well with ordinary washing soda and relatively small currents - 4 amps or so is the max my battery charger will provide - but I leave it in overnight. Obviously the larger the surface area of the rusty part that higher the current needs to be, but if you run at a lower current it just takes longer.

Don't get your polarity reversed or you may not have a part left in the morning <G>

AWEM
 
Re: done rust electrolysis??? ...gota few ?'s for

That's because it contains phosphoric acid in a weak solution iirc. I don't know if it's still around, but there was a rust remover years back called 'Naval Jelly' and another called 'Kurerust' both of which were just phosphoric acid in a gel form. Quite effective but also quite expensive.

The beauty of the electrolytic method is that it is cheap and effective and gets into all the nooks and crannies, and can be left bubbling away while you get on with other things. But bits hanging around on hooks coated in nasty fluids like Naval Jelly tend to get in the way!

When you pull items out of the electrolytic tank it is important to dry them and either prime or oil them, as the surface, being chemically clean, will rust again in no time flat.

AWEM
 
Re: done rust electrolysis??? ...gota few ?'s for

im beginning to think its working just fine...i pulled out a part that still had "surface rust" on it, but it wiped off with a rag and i didnt see any sign of rust there anymore. maybe i just need to let it sit longer...i.e.-overnight. will report back.
tim
 
Re: done rust electrolysis??? ...gota few ?'s for

it went well. what rust is left seems to be more of a paste that wipes off easily with a brush and/or soap and water. i think it is a nice way to do certain parts that are not sand blast friendly, but if it can be blasted, it sure is a heck of a lot faster than electrolysis.
 
Re: done rust electrolysis??? ...gota few ?'s for

The difference is that sandblasting will remove material whether it is rust or the base, whereas the electrolytic method only removes the rust. Also thin parts can be significantly distorted by sandblasting. The micro peening alters the stresses in the surface layer. Found this out quite dramatically when blasting an old hand saw that had rusted. Did one side, took it out to inspect, and although super clean it was like a banana! Doing the other side helped but I never did manage to get it straight!
 
Re: done rust electrolysis??? ...gota few ?'s for

/bcforum/images/%%GRAEMLIN_URL%%/thumbsup.gif Changing a saw into a banana, now there's a miracle. /bcforum/images/%%GRAEMLIN_URL%%/cheers.gif
 
Re: done rust electrolysis??? ...gota few ?'s for

Johnny said:
/bcforum/images/%%GRAEMLIN_URL%%/thumbsup.gif Changing a saw into a banana, now there's a miracle. /bcforum/images/%%GRAEMLIN_URL%%/cheers.gif
Click to expand...

Saws to bananas is no problem, but I'm struggling a bit with the walking on water <G>
 
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