JoelP
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| posted on 15/1/04 at 07:57 PM |
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a good idea shifty! anyone gonna do that or shall i?
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craig1410
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| posted on 15/1/04 at 08:32 PM |
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Guys,
I've already sent an email to Ted Kinsey who wrote the article. If he doesn't reply then I'll email the BHI themselves as they are
opening themselves up to litigation I'd say.
It's amazing how a simple change to a harmless procedure can render it lethal...
I don't know about you guys but I have certainly fished the bits out of the bucket with my bare hands and then washed them under the tap. I
don't know if this stuff can penetrate the skin or not but I'm not a happy man about being exposed to the risk! I did use gloves when the
solution looked like "someone shat in it" for obvious reasons but since I started using the stainless anode it didn't generate
nearly so much gunk so it wasn't necessary.
I'm going to create a new thread to direct people to this warning as this thread is pretty old now and many people probably aren't reading
it now.
Cheers,
Craig.
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Chris_R
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| posted on 13/4/04 at 09:15 PM |
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Has anyone been brave enough to try an engine block, or is that just stupidity?
A bit of slapstick never hurt anyone.
http://www.chris.renney.dsl.pipex.com/
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Mark Allanson
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| posted on 13/4/04 at 10:01 PM |
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Probably OK as long as you remove all the non ferrous parts first, white metal bearings, bronze inserts etc
If you can keep you head, whilst all others around you are losing theirs, you are not fully aware of the situation
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Chris_R
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| posted on 13/4/04 at 10:26 PM |
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Is everyone just using 12v DC?
A bit of slapstick never hurt anyone.
http://www.chris.renney.dsl.pipex.com/
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craig1410
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| posted on 13/4/04 at 11:55 PM |
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Chris,
Most battery chargers put out a bit more than this (between 13 and 14 volts) although you should note that some chargers won't actually put out
any power unless they are connected to a battery. I think someone mentioned that the Halfords automatic charger was like this.
The important thing for this process is the number of Amps of current which flow and this varies quite a lot depending on how close together the anode
and the part being cleaned are. I tend to get about 4 amps myself.
Cheers,
Craig.
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Chris_R
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| posted on 14/4/04 at 07:00 PM |
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Have started the cleaning process and all looks promising. Does anyone know the effect of rubber components left in the solution?
A bit of slapstick never hurt anyone.
http://www.chris.renney.dsl.pipex.com/
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Digger Barnes
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| posted on 14/4/04 at 07:39 PM |
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Should be no problem. As there are no solvents or chemicals that attack rubber in this method.
[Edited on 14/4/04 by Digger Barnes]
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craig1410
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| posted on 14/4/04 at 09:09 PM |
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Chris,
Yes there should be no problems with rubber or plastic bits.
Remember once you remove the finished item from the solution to rinse it thoroughly (I always rinse it under very hot running water as this tends to
evaporate quickly afterwards). Dry the item thoroughly and scrub the black iron dust from it with a wire brush. Then degrease and paint it with
something as quick as you can to avoid any oxidisation (rust) setting in. Ideally paint it with an etch primer or one of the various Zinc paints such
as Davids 182. Rust will form very very quickly on the black iron in particular and this stuff absorbs water which makes it worse so scrub it off.
Cheers,
Craig.
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Chris_R
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| posted on 14/4/04 at 09:12 PM |
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Seems too good to be true, but it's definately working. Was wondering about rubber as I was going to stick my calipers in.
A bit of slapstick never hurt anyone.
http://www.chris.renney.dsl.pipex.com/
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craig1410
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| posted on 14/4/04 at 09:23 PM |
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Chris,
Are you planning to recondition your calipers afterwards or are you just dunking them in as is? If the latter then make sure that no sodium carbonate
solution or water gets inside the caliper or it will corrode the bores. Use extra bleed nipples to seal any holes and make sure your other seals are
in good shape (eg. Handbrake mechanism)
I would also wind the piston right back to avoid any erosion of the piston surface. Of course if the piston is rusty then you should replace it and
not simply try to electrolyse the rust! Is the piston chrome plated or made of stainless steel? If so then you may get harmful chromate by-products
during the process! See my warning about this on another thread.
Cheers,
Craig.
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Chris_R
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| posted on 14/4/04 at 09:38 PM |
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haven't put the whole caliper in yet, only the part that bolts it to the hub. Have just taken it out, wire brushed it a little and rinsed it.
Truely suprised at the result, it's a lot better than I'd expected.
Having spent most of last night reading related post I have read your warning, but thanks for flaging it.
Not sure about the cylinders, can't be stainless as they too are rusted. hopefully gonna recon so they'll be gone before too long.
A bit of slapstick never hurt anyone.
http://www.chris.renney.dsl.pipex.com/
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NS Dev
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| posted on 18/4/04 at 10:18 PM |
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Just started using this system for the first time, (using stainless for a start but having read on may change to mild steel!) I used sodium hydroxide
too (caustic soda) as I had no sodium carbonate. All I can say is whoa!! I saw mention of 4 amp current draw. With my sierra upright 10" away
from the anode (a long piece of stainless steel "endless" jubilee clip) I kept tripping out the charger and drawing 12 amps!! Got it
stable by diluting the solution a a bit and it now runs steady at 10-11 amps!! The cleaning is incredible, as is the amount of gas given off, I did
it outside!!!
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craig1410
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| posted on 18/4/04 at 10:38 PM |
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Yes Sodium Hydroxide (Caustic Soda) is a strong base (alkali) whereas Sodium Carbonate (Washing Soda) is a weak base. The former will produce a much
more conductive solution as you have discovered. The only thing I would caution you on is that this may(?) erode the good metal whereas the Sodium
Carbonate is said to be self-limiting in that it once all the rust is gone the reaction will stop. Gas is still produced but no more metallic
reactions will happen. Also Cautic Soda is a bit more dangerous to handle so don't get it in your eyes or on your skin in concentrated form.
I've just done my sierra rear hubs and carriers tonight and they are all nicely painted using etch primer and Dulux Weathershield Black Gloss.
Very nice!!
By the way, even with 4 Amps going through my solution it gets pretty warm. I bet your solution is almost boiling after a while!!
Cheers,
Craig.
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NS Dev
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| posted on 18/4/04 at 11:18 PM |
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Yes, it did get rather hot!! So did the battery charger!! I was very careful with the Soda. I use boiling Caustic Soda to degrease blocks and stuff
and always wear goggles/gloves etc. I believe that it can blind you pretty quickly and is much worse for the eyes than acid!
It didn't seem to eat the bare steel (I hope) there was no gas coming from the bare areas and they appeared untouched (but if the bearings fall
out now then oops!!)
Cheers,
Nat
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spunky
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 posted on 18/4/04 at 11:46 PM |
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warning
I realise that none of you are idiots but i had the misfortune to witness a colleague at work getting caustic soda in his eye.
The pain he was in and the sight of his face was frightening.
He lost his eye and the degradation of flesh in the socket meant he could not have a false one. Please be careful with this stuff, better still, use
the washing soda and keep the gogs on...
John
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blueshift
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| posted on 19/4/04 at 12:02 AM |
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Thanks for the warning. I don't know about anyone else but I appreciate and mentally file away everyone's little horror stories. I have a
healthy respect for the amount of injury I could do myself while building a locost.
(says he who was welding next to a bucket of paraffin the other day.. oops)
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JoelP
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| posted on 19/4/04 at 11:03 AM |
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i was welding over my plastic fuel tank the other day, felt a bit silly when i remembered!
even worse though, i caught myself trying to cut my thumb nail with the band saw the other day. Gave myself a good slap for that one...
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NS Dev
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| posted on 19/4/04 at 05:16 PM |
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Spunky, I'm sorry to hear that and OUCH, that must have been pretty bad! (big understatement)
I am now going to be more careful again!! I got a load of caustic solution on my hand the other day (went inside the glove) and it didn't hurt
or burn too much but I will now be fully suited, booted and goggled etc etc etc!! I know that caustic soda is bad, I heard about an accident where
somebody using prilled caustic spilt some, still in dry form, into their welly boot. They didn't notice until too late and the sweat made it eat
a substantial part of the foot away! Not at all pleasant I guess.
Anyhow, I will be even more careful from now on!
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Spyderman
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| posted on 19/4/04 at 05:49 PM |
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Please....please do not use Caustic Soda!
The comments that it is worse than Acid are an understement! 
The fumes from it will choke you as well!
Adding water to caustic Soda causes a chemical reaction that creates heat (lots of it). Then putting aluminium into it will make it boil very rapidly
as it eats the ally.
This process is what is used to remove oxidation from aluminium before painting or anodising.
Caustic Soda will burn your skin and the hotter it is the faster it burns. You have mere seconds to wash it off before it scars.
Please don't use it, the dangers far outweigh the benefits!
Sorry to be so negative, but it really is nasty stuff!
Terry
Spyderman
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NS Dev
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| posted on 19/4/04 at 07:29 PM |
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I realise the dangers, but it is very effective.
We work with boiling Sulphuric acid pickling boshes at the steel plant where I work and I do some etching of steel samples with hot concentrated
hydrochloric acid so I realise the dangers of burns etc. It's just that caustic is very good at degreasing (hence why it burns flesh away so
well!) and as you say, is great in weak solution at scouring aluminium as long as it is washed off quickly.
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craig1410
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| posted on 19/4/04 at 07:39 PM |
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I remember a friend of mine at school who got burned badly when he put some pellets of solid caustic soda in his pocket during a lab experiment. I
think we were in 1st year at secondary school and so we didn't really know much about chemistry. He had some spare pellets after his experiment
and for some reason (not theft by the way) he put them in his trouser pocket. He left them there for several hours and I remember him complaining
about intense irritation on the way home on the bus. He had to go to the hospital A&E department when he reached home as he had 2nd degree
chemical burns on his leg... He ended up with a large (approx 3" ) circular scar on his thigh.
Not nice stuff and best left to the professional's (NS Dev you may well be one so best of luck). Even if you think you can handle it (as I
would) then think about kids and animals who may come into contact with it so unless you have a secure storage facility and chemical disposal facility
and all the PPE to go with it then steer clear!
Cheers,
Craig.
[Edited on 19/4/2004 by craig1410]
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NS Dev
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| posted on 19/4/04 at 07:56 PM |
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A fair point Craig, I'm not trying to make out that it's perfectly safe, and you are quite right about what else may come into contact
with it. I dilute the caustic right down and put it down the drain (it is bought as drain unblocker anyway)
I will shut up now so I don't cause seombody to get burnt, but will point out that the caustic is available from common shops as a household
chemical (won't say what/where due to the cautions above!!) so anybody could use it and not realise the seriousness of the dangers.
As an aside I think this is partly down to the "super-safety" culture these days. because we are constantly warned about things being
"dangerous" which never seem to hurt us, we may be blase when something really is very dangerous and we are really at risk of serious
injury if we are not careful!! (or maybe that's just my view, I'll get off the soapbox now!!)
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spunky
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| posted on 19/4/04 at 08:05 PM |
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Hi all,
I'm pleased we have established the dangers of caustic soda. It is evil stuff and I wouldn't recomend using it if there is an alternative.
But as Nsdev points out it is very effective, 'so you pays your money, you takes you chances' Thats what a forum is for- to share
information.
And I am the biggest hypocrite. I have been known to tack without a welding mask, I remove the guards from my angle grinder, cut my nails with a bench
grinder. I find it impossible to work with any sort of gloves on and frequently find myself using petrol to clean components with a fag hanging out my
mouth. (thats a cigarette by the way, before you start... )
all the best
John
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NS Dev
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| posted on 19/4/04 at 08:11 PM |
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Oh no, I'm back again!!!
I used an angle grinder without a guard once to get into a tight corner. I just put the guard back on and started it back up when the wheel exploded,
1 piece of which ended up in my leg! If the guard wasn't back on I fear I may be have been missing a finger or two!!
I didn't do it again!!! but as you say, you know the risk and take it and that's how life is and that's how we learn I suppose (and
the guard still didn't stop the bit in my leg, bl00dy thing!)
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