Citric acid rust removal

[DanielW]

http://corollaperformance.com/TechInfo/sparkplugs.html

 

[Wallace]

I've never tried to remove the central electrode but used the outers many times for various tools by machining off the peened over section above the nut in the lathe. Now I'll be looking for all my old old plugs to dismantle!

 

[DanielW]

This ceramic tip thing,what size internal hole? are we talking for wet sand blasting and will smaller bullets stand up to the job?

Scouring ebay and I come across ceramic necklace beads 19mmx10mm I'm guessing internal hole would be 8mm? at £1.65 for 10 and then I happened to thing ceramic fuse bodys come in different sizes,take the end caps off and you have a ceramic tube.

Should I go back to the drawing board?

 

[mike 109444]

Think 8mm would be to big as you will loose the pressure. I to searched ebay and used the term "ceramic cylinder" and there were some at about 3mmi inside dia which is closer to the Wicks lance.

 

[DanielW]

Think 8mm would be to big as you will loose the pressure. I to searched ebay and used the term "ceramic cylinder" and there were some at about 3mmi inside dia which is closer to the Wicks lance.

Hmmm! dunno about your wickes lance but I have just measured the tip bore internal diameter and it measures 6mm,sadly they used mild steel as it now needs replacing as its rustedmthought it was stainless.

Got a feeling thats why they dropped it from sales due to the nature that the lance tube was mild steel as well.
Still it was worth the money at the time and its done the buisness for me,will just try and open the plastic casement and do some alterations to suit the ceramic tips and change the lance to brass.
Tried once before to open the casement but didn't have much successmwas going to use it as a template for a sand casting mould in Aluminium and make a few to sell on ebay below the stupid asking prices they are flaunting.

 

[Allan G]

I signed up to say thanks! I have used this site for a while to help modify my welder, but i just bought 5kgs of citric acid on ebay for £15 delivered, it worked so well in a couple of hours on some old bolt cutters and bits and bobs that i am shocked! Away to give them a powerwash and quick brush before they go back in for round 2. Cheap and cheerful and easy to do, no more scrubbing away in future for me, delighted!

 

[mike 109444]

Welcome aboard Allan
Don't forget to give them a light oil as they will be bare steel and prone to rust straight away.

 

[conor1n]

Just an FYI guys..

There is a phenomenon called Hydrogen Embrittlement that causes high carbon steel to become brittle when exposed to Citric Acid. I came across the term on Trevs Blog.

He says not to use it on things such as brake discs, wheel hubs etc.. I've used it on my wheel hubs and rear discs. I'm not sure worried about rear brakes as they aren't really used due to the bias. I am wondering should I bin the hubs.. :/ I need to research but it sounds like that might not be necessary.

Hydrogen embrittlement - Wikipedia

en.wikipedia.org

 

[Turbo]

Just an FYI guys..

There is a phenomenon called Hydrogen Embrittlement that causes high carbon steel to become brittle when exposed to Citric Acid. I came across the term on Trevs Blog.

He says not to use it on things such as brake discs, wheel hubs etc.. I've used it on my wheel hubs and rear discs. I'm not sure worried about rear brakes as they aren't really used due to the bias. I am wondering should I bin the hubs.. :/ I need to research but it sounds like that might not be necessary.

Hydrogen embrittlement - Wikipedia

en.wikipedia.org

It has happened to me using electrolysis, it's a known problem as hydrogen is produced as part of the the process. But I cannot see how it could occur with citric acid, I think Trev is getting mixed up!

 

[ronan]

Just an FYI guys..

There is a phenomenon called Hydrogen Embrittlement that causes high carbon steel to become brittle when exposed to Citric Acid. I came across the term on Trevs Blog.

He says not to use it on things such as brake discs, wheel hubs etc.. I've used it on my wheel hubs and rear discs. I'm not sure worried about rear brakes as they aren't really used due to the bias. I am wondering should I bin the hubs.. :/ I need to research but it sounds like that might not be necessary.

Hydrogen embrittlement - Wikipedia

en.wikipedia.org

Bloody hope not, i did a job lot of rusty morse taper drills a few weeks back with citric.

 

[conor1n]

Bloody hope not, i did a job lot of rusty morse taper drills a few weeks back with citric.

Lol, same boat as me then. I have a cousin who is into atoms and molecules... i'll ask her about it.

In the mean time, my hunch is that if it's possible it's bordering on the theoretical side of things and shouldn't harm things.. (*I didn't say that*)

 

[Wallace]

Holy thread resurrection Batman!!
I read up a fair bit on Hydrogen Embrittlement when I was Zinc plating, most of it went over my head but seemed to revolved around electrolytic cleaning, reverse cleaning and the plating process itself. I don't recall anything related to acid dipping causing Hydrogen Embrittlement.

 

[Ross365]

There's no lack of info about hydrogen embrittlement on the net. Citric acid doesn't seem to be of great concern, but hydrogen can be "baked out" by holding the metal at (say) 200'C for some hours; it all depends on the particular situation.

 

[Wallace]

There's no lack of info about hydrogen embrittlement on the net. Citric acid doesn't seem to be of great concern, but hydrogen can be "baked out" by holding the metal at (say) 200'C for some hours; it all depends on the particular situation.

Baking, that was niggling me as something I remember reading about.

 

[TechnicAl]

Just an FYI guys..

There is a phenomenon called Hydrogen Embrittlement that causes high carbon steel to become brittle when exposed to Citric Acid. I came across the term on Trevs Blog.

He says not to use it on things such as brake discs, wheel hubs etc.. I've used it on my wheel hubs and rear discs. I'm not sure worried about rear brakes as they aren't really used due to the bias. I am wondering should I bin the hubs.. :/ I need to research but it sounds like that might not be necessary.

Hydrogen embrittlement - Wikipedia

en.wikipedia.org

It can happen with any acid......the definition of an acid is "An acid is any hydrogen-containing substance that is capable of donating a proton (hydrogen ion) to another substance. A base is a molecule or ion able to accept a hydrogen ion from an acid"

I know of hydrogen embrittlement in welding but in acid dipping Ive only heard of it when the item had been exposed for years.... I dont know enough about acid dipping so Im no expert

 

[Ross365]

Likewise, I cannot claim expertise in this area, but take a look at this.