Tuesday, December 3, 2019

Rust you say? Evaporust to the rescue

I have been collecting and restoring umpteen tools thru the years.  Most, if not all, had some rust issues.  If left alone, your object will continue to deteriorate (rust) and become a useless rusty paper weight.  Rust must be dealt with.  Been using various ways to deal with it thru the years, including electro chemical process.
To me the best and safest way bar none remains Evaporust.  Safe, will not remove metal only the rust, which means, objects can be left soaking longer if you forget without hurting them.   Safe for the environment, septic tanks, your bare hands etc.  Re-usable, just filtered it and re-use.  That helps mitigate the cost of the product.  I buy it by the 4 gallons.

But more importantly, it works and does it safely.  The only other method which works as well, in my book, is electrolysis.  Works great but require a power source, I used a 12 V battery charger, must be used with plenty of ventilation since the by product is the release of hydrogen gas, which can get a tad dangerous....   The anode is consumed in the process, you can get by using Stainless steel for long lasting anode, but doing so release more toxic gas, so I would not advise that.  But my biggest concerns with it is what it does to the object. Possible Hydrogen embrittlement, which can be restored by tempering the object afterward.  And you are left with a toxic mess to dispose (not in your sewer or septic).

So Evaporust it is for me.  I go thru a few gallons a year :-)
As with any rust removal process, scrubbing the loose rust away and degreasing/degunking the object before, helps getting it to work faster and better.  It also keep your precious solution cleaner.
I usually use Krud Kutter for that and a stiff brush.

The beauty of using chemical chelation to de-rust an object is that you do not abrade metal away (like sanding etc). Hence you do not run the risk of erasing some markings. To me its like the results of a good electrolysis job but without all the hassles and dangers.  Museums have been reportly used electrolysis to derust their objects.

With Jean's stuff came a few tools, one was a roll of brace bits.  Unfortunately, inside one large pocket was a few bits which were soaking wet for a while, really did a number to those poor bits.

The bit roll

Some were plated and remained mostly intact, others not so much.

That center bit still has the perfect geometry

A fresh batch of Evaporust, clear yellow


During the process, I take them out of the bath and give them a scrubbing with a stiff stainless steel brush and a green scrubby, I help me gauge the progress and ensure better action by removing more cruds.  I need to do this in order to see the progress and soak longer as needed.

After 22 bits, 2 planes iron and a metal plane body and parts, its starting to get brown.
Perhaps the biggest negative about this method is finding suitable containers 
to handle the size of the object without wasting too much precious liquid.
This was left overnite, and was rotated once in a while 
since the flutes are slightly sticking out of the bath

In the end your object will take a dark blackish color cause by the top layer of loose gunk.
After I'm satisfied, it has worked enough, I'll scrubbed them with the green scrubby, rinse and left with a dull darker grey.

Off its bath in Evaporust, pretty blackish.
The dirtier your liquid, the blacker it will come out.
Yes, sharp eyes readers, I need a new scrubby :-)

Then off to the wire wheel we go.  I use a soft bristle steel wheel, being soft, I wear them out fast and go thru a few.   Mind you, if you only saw my pile of tools, you'll understand why :-)
If you ever wire wheel a rusty object without treating the rust first,  you probably ended up with a shiny dark brown surface.  In this case, after Evaporust,  we go from dull grey to a bare metal shine.  Sometimes the bits take an almost aluminum looks, which I don't care for, but leave it alone and it will darken back. I guess the various colours (shades of grey) depends on the metal composition.  The tell tale demarcation between the steel tip forged welded to a softer iron body becomes visible, due to the colour differences.

Earlier I did a quick test to see the various stages.

Only the nose section was dipped in Evaporust 
(for lack of suitable container :-)
 then wire brushed

The stem was simply wire brushed, no Evaporust first.
It removed surface rust but gave the object a shiny brown appearance

Between these two pics, you can see the transition from
 Evaporust untouched (dull grey) to the right and shinier after wire wheel.
You can also see how it has exposed all the pitting that took place under the rust. 

Here is a Canadian Champion chisel that got dunk in between (seens in first pic of soaking, in my last blog)

The Before

The after
Note the severity of the pitting.
No pitting were it matters the most.  The back will get flattened first 
and I expect it will take out lots of the small pitting. 

The trademark became clearly visible
CANADIAN CHAMPION

Back to our boring bits...

All the bits have been processed, only need some touch up sharpening 
before being put to good use.  Bottom one has been de-rusted as well now.
The two on the far right have been rejected as being too much pitted.


In this case, you can see the flutes sticking out.  If left alone you will be left with a tell tale demarcation line almost impossible to erase.  My solution?  Simply rotate the object once in a while.
Either that or find a more suitable container, or add more liquid.

Evaporust will not harm paint finish, or japanning, but if there was rust under, it will lift the paint in those areas.  Similarly how it will react with plating, if its solid, no harm, rust under, flake off.
I try to avoid wood contact, because wood and liquid don't play nice.
In this case, I kept rotating the chisel as well.

A small block plane.  Note the unharmed paint finish
I always thought these blue and red planes were German, 
but this one has a blade clearly stamped Japan.  The sole and sides are also plated.


Bit on left is OK, the remainder two, need more soaking.
Last on right was later rejected as too much pitting took place.

After its first wire wheel, put back into soaking, there was still rust visible.
BTW That bit has a patented strange nose.  
It looks like a Jennings for the first  few twist then change into a Irwin center bit???
The patent date 23 Oct 1900 (?) must fall on a Tues if US (since 1848 I believe?)
 if not its either a typo (it happened in the past more often than you may think) 
or I read it wrong or Its not a US Patent??  Work in progress


Any drilling bits can benefit greatly from being rust free and shiny, to help the shavings flow out.
In addition those that have a threaded nose to advance the bit, are often impaired by too much rust and cruds in the threads.  Using a file to recut threads is risky at best, you can create more problems than you solved.  Soaking in Evaporust then wire wheel the bit with a soft wire brush, get those pesky threads clean up effortlessly.  The bits could benefit further from a quick buffing on the flutes to help those shavings flow easier, but in my case I never got around to do that and they works just fine.

Lastly, after this chelation process we have exposed fresh metal which can quickly start to rust if left alone.
Drying the object after its water rinse, then wire wheel, and finally wiped with a coat of WD 40 and/or a wipe with Autosol will help keep it rust free.  Your results may very well vary with your geographic location, but flash rust can happen quickly if left alone.  Especially vulnerable are all those small craters left behind by the pitting that took place before hand.  You can sand them out, depending on location, but on drilling bits you have to be careful not to end up tapering toward the nose, making it sure to jam quickly while drilling.  The outside section (often the most pitted) only keep the bit centered, and has no effect on the cutting action.  It is the inside of the flutes, where the shavings glide thru that matters.  The smoother the better chips ejection, the deeper you can go before jamming by choking.    Easily buffed using a shoe shine buffing action by hands, using a long narrow piece of clothe (or whatever).  The idea is to polish, not sand

This mean, avoid the urge to sand the outside pits, and instead, wax your bits.  That will fill in the pores (pits) of the metal affording better protection against rust and it will turn easier, Bonus! :-)

Bits are only to be sharpened from the inside faces.  Please learn and understand the bit cutting geometry before attempting to file them sharp.   If you do not know what you are doing you can quickly ruin a bit, some times mortally :-(

Bob, with a never ending pile awaiting its dip in Evaporust

Full disclosure, not paid or rewarded or whatever by Evaporust to hawk their products, I am just a satisfied customer, that's all folks.



14 comments:

  1. Bob .can you reuse the product multiple times or is it degrading as soon as you dip a rusty bit in?

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  2. I reused it until it is too gunky to work. You can extend its life by filtering it (never had much luck with coffee filter media) so I just keep it in whatever container I have at hand. A tad pricey, but it works safely and thoroughly, it cannot hurt the good metal by forgetting objects in, like I just remember now... :-)

    Yes, reusable many times

    Bob

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  3. The main thing that slow its action down (efficiency) is the gunk. Either on the rusty object (which will end up as gook at the bottom of your solution) or in the liquid already. On you tube, some guy sponsored by Evaporust, use a 45 gallon drum of the stuff in which he dip a plastic wire basket will the parts in. All his gook is at the bottom of the barrel, his objects in the basket never sees it. seem to be lasting forever in that set up.

    Only minor annoyance are the containers required. Some to store the used liquid, do not put back into new stuff. Only add new stuff to old stuff. And a variety of shape containers to dip your objects in it without wasting too much liquid. Its expensive, reusable, and Im not cheap, I'm retired :-) so I get the most out of it. Buy a 4 Gal best buy, sometimes on sale at Busy Bee. Will last you a long time. Me on the other hand maybe 1 year or so :-)

    Bob, who should go see the bits I left soaking yesterday

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  4. Hi Bob
    Evaporust does work very well but I find it a little expensive.You might give citric acid powder a try. You can buy it wherever canning supplies are sold. It's used in making jellies and also used in soda pop so its quite safe. $6 US dollars buys enough for 10 gallons. Walmart sells it or get it onliine to. 1 tablespoon/gal. roughly.
    It works exactly as Evaporust does, I toss the used stuff on the lawn. Grass loves the iron in it.
    Stephen

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  5. Very true Stephen, grass loves iron, and weeds not so much :-)
    I am aware of citric acid methods, never tried but it does sound similar action. I'm just sticking to what works for me right now, on a retired salary :-)

    Bob, who just recovered three other bits from the bath. Wiped beautifully after just a quick hand brush work on them, no wire wheel. They have the right unrusted colour to my eye

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  6. If you are regularly treating long narrow pieces you could use a length of PVC tube (waste water tube) with a plug glued at one end. Here in Belgium, those tubes exist in 32, 40, 50, 80, 90 and 100 mm in diameter.
    Sylvain

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  7. Here they sell plugs which can be unscrewed (in French "tampons de visite") to allow unclogging.(for this use, one would place a "T" or an "Y" on the duct and glue the male thread of the plug to it)
    Sylvain

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  8. Watch the guy I was talking about, use the stuff by the big bucket.
    Hand tool rescue
    https://www.youtube.com/watch?v=Ug2IbkusiUk

    I need some sort of dunking basket system like he is using
    Bob

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  9. Hi Bob,
    You are right to be concerned about hydrogen embrittlement to some extent but I'm not sure there is a remedy as simple as you quoted.

    Hydrogen ions are smaller than hydrogen molecules and can migrate through the structure of steel. When the ions meet each other they combine into molecules and no longer can migrate through the steel. Continuing exposure (most likely not just hours but through use in service) to ionic hydrogen can accumulate hydrogen at sufficient pressure within the steel to blister and even burst.

    Plating is another risk point for hydrogen embrittlement so electrolysis may be undesirable for blades but not castings. I say this because plating uses electrolysis to transport the plated metals to the finished piece.

    I would refrain from acid baths for hardened steel. Low strength steel screws and iron planes should be fine if you like that dull etched look.

    It's been a while since studying this stuff but "tempering" out the hydrogen doesn't sound right and the use of "tempering" means different things to different people.

    Tempering is usually a post quench heat treatment to reduce hardness and build toughness. Adding a second tempering cycle to a tempered piece of steel will most likely reduce hardness further.

    Check out mud trays for taping. They can be useful and also long storage bins.

    https://www.thepaintstore.com/Plastic-Mud-Pan-Removable-Steel-Blades-p/221.htm

    https://akro-mils.com/Products/Types/Plastic-Storage-Containers

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  10. I’ve found that some of the gunkiness is simply due to evaporation from sitting in an open tub. I’ve added water when it got too thick and it seemed to still work ok

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  11. Thanks Paul
    I do notice a smell when doing it in my small Man cave bathroom, so there is some gassing off and evaporation, since it does go down slightly. Every time I put it back in closed containers I never put back in the last bit containing the sludge. Between all these I waste some every time. I always add some fresh stuff when it seems to be slower but I never tried just plain water, will give that a try soon. It's not for the lack of dunking material to experiment with :-)

    Bob

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  12. Bob,

    Thanks for the rust removal info. It is good you and Ralph are fighting the good fight and rescuing the good tools, hopefully to be passed down and in usable condition. My Marples chisel collection has almost taken care of my rust lust. Maybe once I really do retire and have more time I can catch up with you.

    Keep up the good work,

    ken

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  13. Hi Ken
    Yes, its a never ending battle, cause rust never sleeps...especially inside my Canadian snow igloo :-)
    Changes in moisture is a big problems year long.
    The only way I could catch up and win this battle would be to move my tools south, someplace dry :-)
    You will think winter and dry inside air would help, but moving tools in and out of a cold garage to inside a warm house, equal condensation and rust if you are not careful. Hence I buy Evaporust in 4 Ltrs and WD40 by the gallon also.
    You do what you gotta do, i am only the current caretaker of these tools, someone else would be able to keep enjoying them down the road.

    Per Ardua Ad Astra
    Bo, who apparently smells of WD 40 often :-)

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  14. HI STeve
    I do not truly understand what hydrogen embrittlement does to metal, but I do not want to risk some tools like saw plates and etc to it. Besides electrolysis only add to the myriads of precautions you have to be aware of. Evaporust, just dunk and brush off. Well worth the price to me.

    Thanks for your insightful comments, as always

    Bob

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