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Post by Deleted on Jan 4, 2011 10:53:37 GMT
Hi guys A question on cleaning using pickling salts. I remember reading somewhere that a weak solution will work just as well as a strong one but take longer. How accurate is this, I'm cleaning my tender body which just happens to fit into my parts washer tank which I have calculated holds 17 gallons. The tender only just fits into the tank which is 27"x14"dia , I only had about 200 grams of salts left which I have now added to the water in the tank and mixed well. So the question is am I on a trip of wishful thinking that a mixture this weak will work and if so any idea how long? Oh and another factor to consider is the tank is outdoors and so very cold, it is however covered. Pete Edit: whilst looking to order some more salt I noticed that the amount of salt I've put in would normally be enough for 1 gallon, so say I loose another gallon for displacement that means I have a weaker mixture by around 16:1.......  |
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Post by Jim on Jan 4, 2011 17:54:56 GMT
Hi Pete, I take it by 'salts' you mean Citric Acid? Citric is the pickle used here and I've bought it in the local super market. I've also use vinegar with a couple of teaspoons of salt added for small jobs, a mix that was used for cleaning copper prior to enameling. It's true that the weaker the solution the longer it takes but at 16:1 I really have no idea.  Jim |
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Post by Deleted on Jan 4, 2011 18:18:34 GMT
Cheers Jim, I'm using dry acid pickle salts as supplied by varius ME suppliers. Vinegar and salt?, do you think I could add that to the mix, the tender has been in the solution for about 8 hours so far with no change. Even when scrubbed with a toothbrush nothing changes?
Pete
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russell
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Post by russell on Jan 4, 2011 19:33:55 GMT
Any chemical reaction will slow down by a factor of two for every ten degree drop in temperature. Thus at close to zero degrees it will take about six times as long as at 25 C. So at low temperatures you will need a stronger solution.
Personally I use the traditional sulphuric acid, it's quicker and available in supermarkets here!
Russell.
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Post by Deleted on Jan 4, 2011 19:50:02 GMT
Thanks Russell, yes I did suspect that temperature would have an effect but didn't know by how much.
Thank you
Pete
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Post by Jim on Jan 4, 2011 23:16:17 GMT
Pete I'm no expert but I definitley wouldn't mix the pickling agents. I'd also stick to the most user friendly agent, for me that's citric acid. I assume you're wanting to clean your tender prior to painting.
All the best,
Jim
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Post by Boadicea on Jan 5, 2011 7:38:48 GMT
Cheers Jim, I'm using dry acid pickle salts as supplied by varius ME suppliers. Vinegar and salt? Pete Pete, I think this may be your problem - this stuff is sold by some suppliers as a safe alternative to other options. Nobody seems to want to admit what they really are. Burrell2439 is right I think, stick to what we know. Citric acid is comparatively safe and most of us have had success with it. Although it is only available in small sachets in Tesco because apparently the low-life use it as a mixing agent for substances suspicious (as if that would stop it!), it is available from brewing shops and eBay in larger quantities. If you move on to Sulphuric, in the UK there is drain cleaner which purports to be 92% sulphuric. It is, but there is no way of knowing what the concentration was in the first place and there is no way it is conc 92% sulphuric. Trial and error on concentration is the only way to go with this - if you treat it as 92% and dilute it to 5% you will have something quite weak. The only way to know exactly where you are with sulphuric is to buy it as such and dilute it to, say, 5-10%. Conc sulphuric is available from Blackgates if you feel bold enough to use it and have it around. If not, why not use citric - it is known to do the job and it is used in food, so relatively harmless. Pickle has been discussed at length hereMost things in life, from sex to ploughing, are better in the warm! |
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Post by Deleted on Jan 5, 2011 8:52:41 GMT
Thanks for the advice guys, I guess I'll need to experiment a little to get the hang of it, the citric acid from Tesco's, can someone tell me how it's labelled and where abouts they keep it please? I want to try to avoid sulphuric acid what with grandchildren visiting and a pond full of my son's Koi carp...  Many thanks for all the help Pete |
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russell
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Post by russell on Jan 5, 2011 19:26:10 GMT
I want to try to avoid sulphuric acid what with grandchildren visiting and a pond full of my son's Koi carp... I know what you mean regarding grandchildren. They get in everything. I have my pickle in a large plastic toolbox (about 1m x 1/2m x 1/2m) in the garden. When the grandchildren visit the lid is secured with a padlock. I use a 5% solution which works in a reasonable time and isn't that dangerous, although I do have an outside tap next to the tank to rinse the metalwork and my hands if I get splashed. Russell. |
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Post by Deleted on Jan 6, 2011 9:18:55 GMT
Well I think I can confirm that a 16:1 weakened ratio and close to freezing conditions doesn't give the best conditions for cleaning. Having said that it did help and after some wire wool treatment last night the end result was very good. To be fair though the tender was reasonably clean anyway so there wasn't much for the weak acid to do other than to help remove any flux not easily accessible prior to painting. After removing from the acid I gave the whole thing a good clean with detergent and hot water. Last night before bed I sprayed the underside in etching primer, I'll prime the rest of the body today and then look at sealing the tank. I'll post pictures in my build thread later. Thanks again for all the help and advice guys.. Pete |
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