Rust removal with molasses.

[rijidij]

A mate recently told me about using a molasses dip to remove rust from old parts.
Yeah, yeah, I know…….some of you old timers on here will say, “ I’ve been using molasses for the last hundred years to remove rust from some of my old Landy parts.” :D

Anyway, just for interest, I thought I’d give it a try. ;)


First, get some feed grade black molasses from a farm supplies store, about $9 for 5kgs, and mix it with water in a suitable container. I read to mix it anywhere from 10:1 to 20:1. Mine ended up about 15:1.

https://www.aulro.com/afvb/images/imported/2010/10/862.jpg https://www.aulro.com/afvb/images/imported/2010/10/863.jpg

I had some springs for my 2A that needed cleaning up, and a couple of rusty old hand winches.

https://www.aulro.com/afvb/images/imported/2010/10/864.jpg https://www.aulro.com/afvb/images/imported/2010/10/865.jpg

I was told to soak the things for a couple of weeks. I took the springs out after 3 weeks and hosed them off. There was pretty much no sign of rust on the outer surfaces, except for where the rust was thicker or slightly flaky, so I pulled them apart.

https://www.aulro.com/afvb/images/imported/2010/10/866.jpg https://www.aulro.com/afvb/images/imported/2010/10/867.jpg

At this stage I hadn’t done any wire brushing, I just wanted to see how effective the molasses is.
After another week of soaking I hosed the leaves off again. It appears that where the rust is mild, it completely disappears right back to clean bare metal, but where the rust is heavier, it seems to sort of work like a rust converter, but it’s still there.

https://www.aulro.com/afvb/images/imported/2010/10/868.jpg https://www.aulro.com/afvb/images/imported/2010/10/869.jpg

Also, it is not effective where there is grease on the surface, so de-greasing at the start might be helpful.

https://www.aulro.com/afvb/images/imported/2010/10/870.jpg

Reading about the process on the net, it was stated now and then that your items will start to rust again as soon as you take them out of the dip. It does appear this way, but to me it looks more like a sort of dusty residue that brushes off easily.

https://www.aulro.com/afvb/images/imported/2010/10/871.jpg

I took the winches out after 3 weeks and there was a big difference. Just for interest, I gave one of the winches a light wire brush (hardly touched it really) and put it back in the dip.

https://www.aulro.com/afvb/images/imported/2010/10/872.jpg

After another couple of weeks I took the winch out and gave it a hose off. The following pictures are after hosing off, but no wire brushing, just straight out of the dip.

https://www.aulro.com/afvb/images/imported/2010/10/873.jpg https://www.aulro.com/afvb/images/imported/2010/10/874.jpg

The before and after shot tells the story.

https://www.aulro.com/afvb/images/imported/2010/10/875.jpg

Apparently it’s a method popular with old car restoration because it's not too harsh on small or thin items. Here’s a couple of shots from the net.

https://www.aulro.com/afvb/images/imported/2010/10/876.jpg https://www.aulro.com/afvb/images/imported/2010/10/877.jpg



Conclusion………..It’s obviously a slow process, but it works and works well. Best on light rust and grease free surfaces.
For items like the spring leaves, I would probably just attack them with a wire wheel on an angle grinder next time, but for more intricate items like the winches it’s an excellent method which gets into every nook and cranny that might otherwise be quite difficult to get to. It would be great for rusty tools too.

There are commercial products available which I’m guessing work quicker, but probably cost more too.

https://www.aulro.com/afvb/images/imported/2010/10/878.jpg



There’s another rust removal method I’d like to try one day too….. electrolytic rust removal……… explained Here (http://www.smex.net.au/Reference/RustRemoval02.htm) .

https://www.aulro.com/afvb/images/imported/2010/10/879.jpg


So, what other methods of rust removal have you used successfully ??


Cheers, Murray

[p38arover]

Yep. I've been doing it for over 20 years.

See Getting Rid of Rust (http://p38arover.com/rover/rust.html)

[stealth]

I made an acid bath using a 1000 litre white plastic drum. You know the square type that come on a caged pallet. Just cut the top off. I bought 20 litres of Phospheric Acid which you dilute 10.1. It works very well on light and heavy rust and quite quickly. Light rust will strip overnight and heavy scale will take a couple of days. It helps to take it out and chip the scale off after the lighter rust has been eliminated. It can be quite effective on loosening old paint as well. Then just hose off well with water. As soon as it is dry it will start to rust again so I treated everything with fish oil which is great for creeping into seams and crevices and seals the metal. Once the fish oil has dried it can be primed and painted as normal. I restored a LJ Torana coupe for my son a few years ago and rebuilt the body shell which was riddled with rust. Using a reasonably sound donor 4 door body I cut all the rust repair pieces out and treated any rusted bits in the acid first. The end result was a solid body and no rust. The entire body was fish oiled inside and underneath and in all panel joins and seams. I didn't use fish oil on the external panel surfaces where it was not needed. It was then coated in red oxide, primed and painted using acrylic laquer. There was no problems with any paint reaction and the finish in the end was superb. I have other things that I treated in the acid and fishoiled which have not been painted over and they have been sitting around for about 4-5 years and the rust has not re-appeared. Sealing with the fish oil is the key I think. Where possible I prefer sandblasting to remove rust and priming with two pack primer. The surface preparation is so much better and the primer sticks forever. Might be expensive but you get what you pay for. Sand blasting has its limitations on lighter sheetmetal though and doesn't get into tight surfaces. Warning on the acid though. It is totally unsuitable for cast metal and high tensile steel (Springs, brake drums, casings etc). It starts to dissolve the surface very quickly. It will completely dissolve cast aluminium. It will dissolve ordinary mild steel eventually as well but that takes a long time. Very effective

[350RRC]

Posted this info before........ Hydro tomato farms use phosphoric acid to control pH levels because it is much safer for employees to handle compared with hydrochloric, for example.

20 litre drum (about 80% conc) cost me $65 from a mate with a hydro farm.

One trick using this diluted (about 10% conc) is to let the part dry without washing the acid off. Can be painted over when dry and resists further rust for a very long time on parts such as washers on alloy wheel nuts.

cheers, DL

[85 county]

Phosphoric acid you can recycle. Cool it down and a crystal will form. Filter add more water and you are all go again.

Crystal’s ferrous sulfate can go on the garden in very small quantities

[jazzaD1]

I use the electrolysis method, using some scrap steel as an anode, and a Sodium Carbonate solution as the electrolyte, it works great, and fast, it removes paint in sheets, degreases parts and removes all traces of rust

I'll try and get some pics up here soon

[slug_burner]

I use the electrolysis method, using some scrap steel as an anode, and a Sodium Carbonate solution as the electrolyte, it works great, and fast, it removes paint in sheets, degreases parts and removes all traces of rust

I'll try and get some pics up here soon

I too can vouch for the electrolysis method. I used electric soda crystals as used in bath salts. It worked fairly quickly, I did not have the patience to do the molasses method.

[Mick_Marsh]

A mate recently told me about using a molasses dip to remove rust from old parts.
Cheers, Murray
Would this process be able to be done in at old metal (enamelled) bathtub? Would it eventually corrode the bathtub?

[rijidij]

Would this process be able to be done in at old metal (enamelled) bathtub? Would it eventually corrode the bathtub?

I don't think there would be any problem, even if there was some enamel chips as it's a comparatively gentle process. It seems to remove the rust, but not 'eat' the metal away.
Molasses comes from sugar cane and it's fed to animals, so it's certainly not considered a dangerous chemical.
I'm not sure what the rust eating component of molasses is.

Cheers, Murray

[Randylandy]

I'm guessing its the sugar that is corrosive. used to have some coke concentrate that they use in the drink machines. Over xmas period the rats got into it and when we came back to work should have seen the mess that stuff ate into anything and everything. Made you think twice about drinking coke.

[POD]

Used molasses at a place I worked at about 20 years ago to clean up rusty superphosphate gear on potato planters. Anyone who's worked in agriculture knows what super will do to metal.
We were told to mix it 50/50 with water and leave the stuff a couple of months. Of course we forgot about the stuff and found it about 6 months later, tipped the bits out and hosed them off with a pressure washer. They were like brand new, looked like they had just been cast, no wire brushing required.

[p38arover]

Vinegar?

See Cookie's Crap Corvette Tips No.1 (http://www.cookhaus.co.uk/vinegar/index.htm)

Lots of pics. It looks well worth a try.

[rijidij]

He uses malt vinegar. Do you reckon any vinegar would work, or only particular types of vinegar. He doesn't give too many details.

[slug_burner]

vinegar = mild acid

Don't think it would make too much difference.

[Homestar]

vinegar = mild acid

Don't think it would make too much difference.

All proprietry rust converters are based on acids anyway - the most common is phosphoric, but there are others that use tanic acid. The acid soaks into the porus iron oxide (rust) and, in the case of a phosphoric based rust converter, converts the iron oxide into iron phosphate - which is hard, and forms a strong bond to the parent metal. The vinegar is soaking into the iron oxide the same way, but not into the parent metal, so it releases the strong bond that the iron oxide has to the metal. As shown on the pics, it is then easy to brush away. If the metal is washed clean of all traces of the vinegar after treatment, then protected properly afterwards, there would be no ill affects to the metal.

Cheers - Gav.

[Bigbjorn]

Used molasses at a place I worked at about 20 years ago to clean up rusty superphosphate gear on potato planters. Anyone who's worked in agriculture knows what super will do to metal.
We were told to mix it 50/50 with water and leave the stuff a couple of months. Of course we forgot about the stuff and found it about 6 months later, tipped the bits out and hosed them off with a pressure washer. They were like brand new, looked like they had just been cast, no wire brushing required.

Fertilizer is an absolutely deadly corrosive. Supplied skid steer loaders to several fertilizer works when I was selling them. Usually they were throw away after three years. One actually got so bad it broke in half on the job. One company started an evening shift and fitted work lights to the machines. All OK until they got a wet night and within minutes of switching on the work lights all the spade terminals disappeared and the harnesses fell off the lights under the corrosive influence of electricity and wet fertilizer dust. The relatively low cost of these machines and the amount of damage they sustained precluded extensive and expensive anti-corrosion coatings and maintenance thereof. Just buy more.

[chazza]

Would this process be able to be done in at old metal (enamelled) bathtub? Would it eventually corrode the bathtub?

In my experience (15 years) the molasses will eventually corrode through the steel but it takes quite some time and I have never lost a part despite being forgetful. I use plastic baths, the biggest I made was builder's plastic draped inside a dry-brick enclosure in which I did my S1 axles. Line the bath with plastic :D

Murray; items such as springs are best disassembled and wire brushing by hand every now and then, speeds the process up considerably and molasses will completely remove every bit of rust, whereas many rust converters tend to work on the surface and don't penetrate to the bottom of the pits.

Using hot water makes the process even faster :D I use Ranex on the clean bits and then paint,

Cheers Charlie

PS Thanks for posting - I wish someone had told me about molasses when I first started fooling around with cars!

[philco]

Great idea, pity the trailer is too big to go in a tub.

[ScottW]

This whole idea is new to me, but I wish I knew about it earlier. I have been fixing up an old chevvy for a while.
What effect would this have on rubber seals, say in a water pump off a small block chev? I have just pulled one off the engine and need to give it a quick clean up to paint it. It's fairly new, but has been sitting around unpainted for a few years after gong through the salt air on the boat from the US.

[Homestar]

It would have no affect on the rubber seal - molasses comes in plastic tubs, and I think old age would break the plastic down before the molasses would...

Cheers - Gav

[Mick_Marsh]

I thought I'd give it a go myself. I have some badly rusting 101 parts that I want to remove the rust, stop the rusting and then measure them up so I can draw them up and get them re-manufactured from gal.
30199
I bought 2.5kg of molasses from the local stock feed suppliers round the corner for less than eight dollars. I put half of it with four litres of water and mixed it up well. I put the two bits of mostly rust in about midday today. I have just checked the progress and noticed some very fine bubbles of gas above where the parts are.
30203
Evidence of a chemical reaction taking place.

Oh and it makes the laundry smell nice if you like the smell of molasses.

[hodgo]

DON'T place Any none ferris metals in molasses as you wont get it back. It converts allay and brass to a horrible sandy mess in the botton of the tub.

hodgo

[Homestar]

I'd be interested to see how these come out - keep us posted on the progress...

Cheers - Gav

[Mick_Marsh]

DON'T place Any none ferris metals in molasses as you wont get it back. It converts allay and brass to a horrible sandy mess in the botton of the tub.

hodgo
I'll be testing that. There are the remnants of some rivets in the parts I've put into the bucket.

[chazza]

That is a pretty strong brew Mick!

1 part molasses to 10 parts water is usually strong enough. Quite often one can see the outline of the part in gas bubbles on the surface :D

Cheers Charlie

[Mick_Marsh]

That is a pretty strong brew Mick!

1 part molasses to 10 parts water is usually strong enough. Quite often one can see the outline of the part in gas bubbles on the surface :D

Cheers Charlie
Molasses is cheap. Less than a medium Big Mac meal deal.
There was a lot of rust.
Do you think I should dilute the solution?

[numpty]

Molasses is cheap. Less than a medium Big Mac meal deal.
There was a lot of rust.
Do you think I should dilute the solution?

Used to be cheap. 200 l for $25 direct from Nambour Sugar Mill.

Damn site more expensive than that now.....if you can get it.

[Tote]

20 Lt tub from my local stockfeed/hardware store was $32 last weekend but I'm a long way from where any sugar cane is grown.

Regards,
Tote

[Mick_Marsh]

Gleamed from another site:

Question
I have a friend who uses molasses to clean rust off old iron items collected from the bush. The rusty iron article is placed in a jar of molasses solution (nine parts water, one part molasses) and left for two weeks. After this time, the article comes out clean and almost shiny. What is happening here?

Answer
Molasses contains chelating agents. These are made of molecules that are shaped a bit like the claws of a crab--the word chelating comes directly from the Latin word chele, meaning claw. They can envelop metal atoms on the surface of an object, trapping them and removing them. Molasses owes its properties to cyclic hydroxamic acids which are powerful chelators of iron.

More of these compounds are found if the molasses is derived from sugar beet rather than cane sugar. The plants from which molasses is made presumably use these chelating agents to help them extract minerals from the soil. Interestingly, there are aerobic microorganisms that use similar cyclic hydroxamic acids to scavenge iron. So plants and microbes appear to use the same chelation strategy to obtain their daily ration of iron.

The same process is at work when you clean old coins with Vegemite or cola. The power of chelating agents also explains why the insides of tomato tins need to be lacquered. The citric acid in the tomatoes would dissolve the metal of the container if the lacquer were not present. Household cleaning agents, especially detergents and shampoos, also rely on chelation. These soften water to make it more effective during the cleaning process.

Chelation has its uses in medicine, too. EDTA or ethylenediamine tetraacetic acid is used as a chelating agent to control levels of calcium in the body and can reduce the effects of mercury or lead poisoning.

[bobslandies]

Hi Mick,

The molasses needs to ferment before it really starts to work effectively - depending on the temperature this takes a few days and a froth forms on the top. It's a good idea to move the items occasionally to stop masking by bits sitting against each other.

In the fermentation process acetic acid is formed and that is what does the de-rusting. If you have small items - ie nuts and bolts, etc just go to the supermarket and get a bottle of cheap cleaning vinegar - it works the same way and quite quickly!

Hodgo's warning is important - no aluminium, diecast, non-ferrous - they will dissolve. Some cast iron is also affected.

Bob

[Mick_Marsh]

Bob,
They are doing very well. I look at them every day.
There are pop rivets in the two pieces and, as of last night, seem uneffected.
The froth started the almost as soon as I put them in.
By what you are saying, over time the acid in the solution must get stronger. Also, in the process, the acid must get used up. Therefore, the mixture must go off with time and use. Any idea how long it will last?
As a consequence of this experiment, my laundry smells nice.

[Tote]

Smells nice as in like the Bundy distillery?:twisted:

Regards,
Tote

[numpty]

20 Lt tub from my local stockfeed/hardware store was $32 last weekend but I'm a long way from where any sugar cane is grown.

Regards,
Tote

As I said, expensive......$320 for what used to cost $25 not so long ago.

[Mick_Marsh]

Time for a one week update.
The solution appears to have become thicker. Mould is also growing on the surface.
Quite a lot of rust has dissolved away already (although you wouldn't think it).
30462
The rivets appear to be unchanged.

[101RRS]

I tried a mix of 1:10 molasses a couple of years ago and was most unimpressed with the result. I put in a rusty bike tank that had all the paint removed - after a month the shiny metal bits were a little more shiny but the rust was there and had not moved. I moved the tank every couple of days and left it completely submerged for about 4 weeks.

Was a waste of time.

Garry

[Mick_Marsh]

I tried a mix of 1:10 molasses a couple of years ago and was most unimpressed with the result. I put in a rusty bike tank that had all the paint removed - after a month the shiny metal bits were a little more shiny but the rust was there and had not moved. I moved the tank every couple of days and left it completely submerged for about 4 weeks.

Was a waste of time.

Garry
Luckily I don't have to sit there 24/7 looking at it.
I have a few items that need to be de-rusted. I've been looking for a product I used about twenty years ago but they must have stopped making it. Most of the products on the shelf are rust converters and not rust dissolvers and they're all nasty.
I'm a very patient fellow and am willing to wait.
I should be able to dispose of the leftovers in the compost bin.

[groucho]

Try chipping the big flaky rust bubbles off. it gives the molasses less work to do.......

[Tote]

After 6 days in a mix of 13lt of molassis in a 55lt black plastic garbage bin the battery carrier I brought from Tony S is pretty much clean and ready to paint. I hit it with the gurney this afternoon and put it back in the molassis but its just about perfect.
Before pic, you can see it at the back, I'll post the after pic tomorrow if I get a chance.
https://www.aulro.com/afvb/images/imported/2010/11/1685.jpg

Regards,
Tote

[Mick_Marsh]

It's really bubbling now.
30629
The mould growing on the surface is also clearly visible. I'll remove that.

[Tote]

After 6 days in a mix of 13lt of molassis in a 55lt black plastic garbage bin the battery carrier I brought from Tony S is pretty much clean and ready to paint. I hit it with the gurney this afternoon and put it back in the molassis but its just about perfect.
Before pic, you can see it at the back, I'll post the after pic tomorrow if I get a chance.
https://www.aulro.com/afvb/images/imported/2010/11/1685.jpg


And the after shots, this has been soaking for nine days, I cleaned it up with the Gerni and dried it with a heat gun.
http://i4.photobucket.com/albums/y127/toteau/Series%201/IMG_3076.jpg

http://i4.photobucket.com/albums/y127/toteau/Series%201/IMG_3077.jpg

http://i4.photobucket.com/albums/y127/toteau/Series%201/IMG_3078.jpg


Regards,
Tote

[Mick_Marsh]

Just an update.
Two weeks now.
The solution is bubbling heaps. I wonder what gas it is.
30839
Lots of the rust has gone.
There is pitting on the pop rivets.
The observable results are supporting hodgo's comments regarding non ferrous metals. That could be an advantage.
30840
The laundry (where this process is taking place) is starting to smell more acidic (vinegarish) which supports bobslandies comments. I think I'll be moving it to the garden shed soon.

[Lakey]

Murray, I've been using molasses for a while now also. I used to use Phosphoric Acid which works well but if you forget you have something soaking it can be a bit disastrous. The molasses on the other hand doesn’t seem to attack the metal, only the rust. I’ve not done anything major with the molasses as yet, only an old block and tackle which is so far coming up okay.

I was thinking of doing my springs before I saw your post but was wondering if you need to apply any grease or lubricant of some kind between the leaves when re-assembling. I had them reset about 15 years or more back but since then the project stalled so they had been back on the chassis but then just sitting in the weather so are now a bit rusty. Also if I paint them after treatment should it be before or after reassembly? Anybody have an opinion?

Cheers and thanks again for the interesting post Murray
Lakey

[rijidij]

Murray, I've been using molasses for a while now also. I used to use Phosphoric Acid which works well but if you forget you have something soaking it can be a bit disastrous. The molasses on the other hand doesn’t seem to attack the metal, only the rust. I’ve not done anything major with the molasses as yet, only an old block and tackle which is so far coming up okay.

I was thinking of doing my springs before I saw your post but was wondering if you need to apply any grease or lubricant of some kind between the leaves when re-assembling. I had them reset about 15 years or more back but since then the project stalled so they had been back on the chassis but then just sitting in the weather so are now a bit rusty. Also if I paint them after treatment should it be before or after reassembly? Anybody have an opinion?

Cheers and thanks again for the interesting post Murray
Lakey

Before I re-assembled my springs I used 'POR5 Metal Ready' on the bare metal, then a bit of copper grease between the leaves and painted them after they were together with some black 'Stone Guard' (anti chip under body coating) I had all this stuff in the shed already so I thought I'd see how it goes.

https://www.aulro.com/afvb/images/imported/2010/11/1167.jpg

Another thing I've been wondering is, how long does the molasses last. Does it lose it's effectiveness. I'm soaking some other things in the same mix at the moment and I notice that it's not bubbling or foaming like it did before, but it still seems to be working fine.

Cheers, Murray

[Mick_Marsh]

Third week.
Lots of shiny metal.
31108

[russellrovers]

I tried a mix of 1:10 molasses a couple of years ago and was most unimpressed with the result. I put in a rusty bike tank that had all the paint removed - after a month the shiny metal bits were a little more shiny but the rust was there and had not moved. I moved the tank every couple of days and left it completely submerged for about 4 weeks.

Was a waste of time.

Garry
cheaps skate 25 litres to a 44 drum comes out perfect after 4 days the product lasts only so long have been using it for years jim

[wizzid]

Yesterday mixed up a 10:1 molasses brew and started soaking some suspension bits and radiator support brackets off the "New County" and left the tub in the sun. Had a look this arvo and is bubbling away already. Will be interesting to see how long it takes for everything to clean up . BTW a 20lt tub set me back $25 from the local feed and grain.

[Mick_Marsh]

Oh ****!
I forgot!

[FenianEel]

Used to be cheap. 200 l for $25 direct from Nambour Sugar Mill.

Damn site more expensive than that now.....if you can get it.
Now there's no mill, no cheap molasses, and bugger all cane on the Coast:(

I used molasses to clean some tools from an original LR tool roll, from one of the Series 3's. It worked a treat.

[roverrescue]

Just picked up 5L of molassess for 65c a litre.
Plan on derusting a few bits and pieces that have not enjoyed the humidity.
So not serious rust but just a bit worse than flash rust.

I read elswhere to soak in phosphorc acid after the molasses to stop flash rust.
Rijidij recommened POR5 Metal Ready.
Would any good metal primer do or is the POR stuff the goto?

Steve

[87County]

While this thread is headed molasses, I'll add this for general info....

IMHO the first thing to do is to decide whether rust conversion (to phosphate) or rust removal is required.

If rust conversion is required there is a product called ranex rustbuster (from bunnings type shops) which is available in a spray bottle, obviously a phosphoric acid type preparation which converts a lightly rusted finish to a dark grey phosphate - it depends on the film of rust to have something to convert to the phosphate

If rust removal is desired, citric acid can be used instead of molasses. Mixed 2%-5% powder to water, it is great for removing the rust that is usually on garage or clearing sale items including screws, chisels, screwdrivers etc etc. Items need to be totally immersed in the mixture and it doesn't seem to "keep attacking" the base steel or iron. After 8hrs, the first layer of corrosion can be carded off with coarse cloth or hessian, and the item returned to the solution.

NB: Use only on ferrous alloys or iron (they're the only rusters anyway)

Citric acid is obtainable from grocery suppliers and is used in the food industry in things like lemonade (also has other industrial uses).

The stuff I use is produced by Windsor Farm Foods - Home (http://www.windsorfarm.com.au/). I imagine that they would be happy to tell you who sells it near you. A 1 kg container of the powder is under $15 - lasts a long time

[Sam Ball]

For those that are interested, I was telling a mate of mine who is a dentist about the molasses, and he said that as the molasses begins to ferment and bacteria is created, the bacteria creates acid as happens with cavities in teeth, and this is what eats the rust.

Not sure about how long it last for, but have used it a lot and works brilliantly every time.

[Stormy]

While this thread is headed molasses, I'll add this for general info....

IMHO the first thing to do is to decide whether rust conversion (to phosphate) or rust removal is required.

If rust conversion is required there is a product called ranex rustbuster (from bunnings type shops) which is available in a spray bottle, obviously a phosphoric acid type preparation which converts a lightly rusted finish to a dark grey phosphate - it depends on the film of rust to have something to convert to the phosphate

If rust removal is desired, citric acid can be used instead of molasses. Mixed 2%-5% powder to water, it is great for removing the rust that is usually on garage or clearing sale items including screws, chisels, screwdrivers etc etc. Items need to be totally immersed in the mixture and it doesn't seem to "keep attacking" the base steel or iron. After 8hrs, the first layer of corrosion can be carded off with coarse cloth or hessian, and the item returned to the solution.

NB: Use only on ferrous alloys or iron (they're the only rusters anyway)

Citric acid is obtainable from grocery suppliers and is used in the food industry in things like lemonade (also has other industrial uses).

The stuff I use is produced by Windsor Farm Foods - Home (http://www.windsorfarm.com.au/). I imagine that they would be happy to tell you who sells it near you. A 1 kg container of the powder is under $15 - lasts a long time
With the use of molasses, pour a small amount of beer into the mix, this speeds up the start of the process. It works best when used in warmer temperatures. The ratio of molasses to water is not critical, its more likey to become contamenated with mould etc rather than become exhausted. Mixture as weak as 30:1 seem to work. Another alternative is vinegar, this makes alot less mess than molasses. I have tried it on a conrod from a model T and it didn't seem to harm the bearing babit. It also seems to work on alloy, just try an experiment first.

[Titch101]

Molasses is also a fantastic addition to your lawns/garden as the microbes in the soil go ballistic on it giving you healthier plants/grass.
I just use 2 cups in a 9L watering can and keep topping up with water till all the molasses has dissolved.
Try it on a patch of grass and see the difference over a few weeks.

[Lotz-A-Landies]

With the use of molasses, pour a small amount of beer into the mix, this speeds up the start of the process. It works best when used in warmer temperatures. The ratio of molasses to water is not critical, its more likey to become contamenated with mould etc rather than become exhausted. Mixture as weak as 30:1 seem to work. Another alternative is vinegar, this makes alot less mess than molasses. I have tried it on a conrod from a model T and it didn't seem to harm the bearing babit. It also seems to work on alloy, just try an experiment first.A 1:4 (molases:water) will eat white metals like aluminium, lead and zinc. Put a siezed block into a bath and in a couple of weeks you'll have a clean block with the rings sitting in the hollow bores.

I currently have a bath in the shed with a couple of unpainted RRc sill tanks that have been outside unprotected for 18 months, after 4 days I had to end for end then to do the other end. This morning in went a D^D pick head. I should do a couple more and take them to Corowa! :)

[VladTepes]

When happy with the result how do you clean the molasses off ? Just water ?

And these ratios people talk about - is it diluting the molasses slgightly with water, or mostly ater with some molasses added ?

[gromit]

When happy with the result how do you clean the molasses off ? Just water ?

And these ratios people talk about - is it diluting the molasses slgightly with water, or mostly ater with some molasses added ?


Clean with water, dry and you can watch the rust form......needs to be protected fairly quickly.

Mostly water. Have seen 12:1, 7:1 and various ratio's quoted, mine is about 7:1.

Colin

[Lotz-A-Landies]

When happy with the result how do you clean the molasses off ? Just water ?

And these ratios people talk about - is it diluting the molasses slgightly with water, or mostly ater with some molasses added ? me gig lot ater lit lases! :twisted: :D :D


I have seen documents with ratios (water:molases) of between 3 or 4:1 to as dilute as 12:1.

The more concentrated the quicker it works and potentially the more corrosive it is to white metals.

It doesn't remove paint.

With heavily rusted items it is worthwhile soaking for a few days and then removing and hitting it with a wire brush then return it to the bath. The surface is quite reactive when removed from the bath and after hosing off you will see surface oxidation occurring before your eyes.

Even something like WD40 can be used to protect the surface temporarily.

[Stormy]

A 1:4 (molases:water) will eat white metals like aluminium, lead and zinc. Put a siezed block into a bath and in a couple of weeks you'll have a clean block with the rings sitting in the hollow bores.

I currently have a bath in the shed with a couple of unpainted RRc sill tanks that have been outside unprotected for 18 months, after 4 days I had to end for end then to do the other end. This morning in went a D^D pick head. I should do a couple more and take them to Corowa! :)
The reason for the eating away of white metals may be due to an electrolytic action like happens in a battery or cell. This happens when differeent metals are immersed in an electrolyte. One of the metals is "sacrificed" during the action. It is very important to test with an experiment first when ever any chemical is used for cleaning etc. The bath used must also be non metalic to prevent this happening. I use corregated plastic feed troughs maid by Minto, they are available in various lenths and long items like axle shafts etc can be immersed if rquired.The 200 litre barrels with the top cutoff are good for engine blocks. Try the vinegar alternative. I like it, it make a lot less mess and is very good for small parts. To protect against rust recurring, use ensis fluid. This comes out of the tin with the viscocity of dlesel, but dries like grease and will protect for years if need be. It can be removed with turps when the part is needed.

[Lotz-A-Landies]

However if you have a seized block where you have tried all the regular methods to get the pistons out, the fact that it eats white metals, is a benefit!

New pistons are easier to find than a 1948 side plate Landy block.

[incisor]

i was feeling a little adventerous this morning and had been reading all the stories about molasses and then about washing soda and 12v chargers...

hmmmm

why not combine the molasses and the 12v i thought.

so off i went...

used an old laptop power supply that punches out a whopping 2a @ 12v dc and wired up the solex carby arm i had in my little molasses tank

the arm had been in the tank 2 days already and the molasses only mixture had barely eaten thru the rusty surface, it was still dark brown and had a heavy coat of surface rust.

well turned the switch on and in 2 or three minutes i had what looked like a lovely head on a pint of stout!

https://www.aulro.com/afvb/

obviously it's working i thought.

off i went to do some work...

about half an hour later i wander out to have a look... still a big head

hmmmm

lets have a bopeep.

turned the power off pulled it out of the bath and it is almost gleaming :p

https://www.aulro.com/afvb/

whoa! that sped the process up a bit :p

anyone else been stupid enough to try it?

[BathurstTom]

I'm guessing its the sugar that is corrosive. used to have some coke concentrate that they use in the drink machines. Over xmas period the rats got into it and when we came back to work should have seen the mess that stuff ate into anything and everything. Made you think twice about drinking coke.

Coke used to have phosophoric acid in it, not sure if it still does?

Tom.

P.S. just checked - it still does (http://en.wikipedia.org/wiki/Coca-Cola#Ingredients)

[Mick_Marsh]

anyone else been stupid enough to try it?
No, but seeing the results ...........

Thanks Inc.

[slug_burner]

i was feeling a little adventerous this morning and had been reading all the stories about molasses and then about washing soda and 12v chargers...

hmmmm

why not combine the molasses and the 12v i thought.

so off i went...

used an old laptop power supply that punches out a whopping 2a @ 12v dc and wired up the solex carby arm i had in my little molasses tank

the arm had been in the tank 2 days already and the molasses only mixture had barely eaten thru the rusty surface, it was still dark brown and had a heavy coat of surface rust.

well turned the switch on and in 2 or three minutes i had what looked like a lovely head on a pint of stout!

http://www.aulro.com/afvb/attachment.php?attachmentid=57630&stc=1&d=1362786752

obviously it's working i thought.

off i went to do some work...

about half an hour later i wander out to have a look... still a big head

hmmmm

lets have a bopeep.

turned the power off pulled it out of the bath and it is almost gleaming :p

http://www.aulro.com/afvb/attachment.php?attachmentid=57631&stc=1&d=1362786784

whoa! that sped the process up a bit :p

anyone else been stupid enough to try it?

My high school chemistry that I remember tells me pH is a measure of the concentration hydroxide ions OH, these ions can carry current therefore allows the electrolosis process to work just like the lectric soda crystals in water do.

[pasi]

hello incisor,

when you say, "used an old laptop power supply that punches out a whopping 2a @ 12v dc and wired up the solex carby arm i had in my little molasses tank", did you attached both wires or only one to the piece you were cleaning?

cheers,

pasi

[slug_burner]

hello incisor,

when you say, "used an old laptop power supply that punches out a whopping 2a @ 12v dc and wired up the solex carby arm i had in my little molasses tank", did you attached both wires or only one to the piece you were cleaning?

cheers,

pasi

You only put one wire onto the piece you are cleaning, you need to put the other wire onto another piece of metal in the bath, the rust then travels off the piece you're cleaning to the other.

[Lakey]

I've so far managed to blow one power source. Question I have is which wire to part and which to the sacrificial bit + or - ? Assume + to part being cleaned but wasn't sure.

Cheers
Lakey

[slug_burner]

I've so far managed to blow one power source. Question I have is which wire to part and which to the sacrificial bit + or - ? Assume + to part being cleaned but wasn't sure.

Cheers
Lakey

Negative on the article to be cleaned. This is not related to cleaning with molasses but electrolysis rust removal, usually using lectric soda crystals in the water to provide the conductive medium. Molasses produces a mild acid that performs the cleaning. However electrolysis works with an acid as well.

[VladTepes]

The follow up Q of course is... one one removes all the rust from old tools (as I'm planning) how then do you prevent the tools from rusting again?

[Mick_Marsh]

They will rust again, quickly.
I'd spray them with RP7, CRC or something similar.

[wrinklearthur]

They will rust again, quickly.
I'd spray them with RP7, CRC or something similar.

I wonder if cutting oil mixed with the water used to wash the parts down would work?
.

[Lakey]

The follow up Q of course is... one one removes all the rust from old tools (as I'm planning) how then do you prevent the tools from rusting again?

I immerse in a bucket of hot water (from the hot tap in the laundry so not thermostat controlled). Leave to soak for a few minutes then out and cleaned up then back in the hot. Depending on the size it may need repeating the process untill all the molasses is cleaned off. If you have good gloves it's even better to do the cleaning in the hot water. By heating the metal in the hot water it dries quite quickly when it comes out so does not have a chance to start rusting so quickly.

I usually then give a light wire brush and a coat of cold galv so the zinc in galv will look after any light surface rust that forms but by heating it does seem to slow the process considerably. Heating in hot water is unlikely to affect any tempering I'd think.

Cheers
Lakey

[slug_burner]

The follow up Q of course is... one one removes all the rust from old tools (as I'm planning) how then do you prevent the tools from rusting again?

Use usually works.

But if like most where we don't use our tools daily you then need to prevent oxygen and moisture from getting to the surface of the metal. Garden tools get a coat of linseed oil on the wooden handles and the metal surfaces, other substances such as lanolin have been used on a broad range of hand tools from cabinet makers tools to rotary machine cutting tool metal surfaces. Short of barriers such as the easily removed oils then you get the hard setting barriers like paints and then the sacrificial coatings or platings some of which are barriers. Take your pick.

[Hoges]

Wipe the newly de-rusted tools with a cloth moistened with Lanotec and then let the tool dry. Once it's dry the Lanotec coating will survive (almost) being sprayed with a 70 Bar power washer....

[350RRC]

Bit of grave digging, but this may save you all a lot of time and money.

Have tried molasses, yes it works, takes time.

In the process of de rusting a 4000 gal tankstand in pieces. Have two capped 100mm sewer tubes 4m long sitting diagonally to the ground, one full of fermented molasses, one full of 20% phosphoric acid.

After 4 days in the molasses tube there is a bit of action........ some rust has gone (maybe 10%).

After one day in the phosphoric tube all rust is gone, including pits and paint.

I know from experience to just let the phosphoric treated steel dry and keep it dry till primed.

Don't rinse the finish off!

Maybe just wipe with a dry rag before priming (I have my own special for that).

20 L of 83% phosphoric cost me $65 a couple of years ago through an ag trade account. Pretty cheap when diluted to 20%. Most commercial similars are 17% at most.

To de-rust this whole thing is going to cost me $30 max for acid.

cheers, DL

[Hoges]

It's probably better practice to carefully wash off any excess phosphoric acid with water. When the phosphoric acid has done its work, there should be a deep grey/black finish on the iron. This is iron phosphate, it is chemically bonded to the substrate and is quite insoluble in water. Gently washing off remaining acid with water and allowing the surface to air dry will then get rid of any excess phosphoric acid and provide a better etching surface for the primer to adhere to... and not interfere with subsequent coatings.

[350RRC]

I'm not using a conventional primer. I make it myself........ total oxygen denier.

The dust left over after drying just gets wiped off with a rag or brush and away we go.

I appreciate your comments Hoges.

DL