David Littlewood | 08/09/2012 11:31:20 |
533 forum posts |
Posted by John McNamara on 08/09/2012 03:53:13:
Teflon filled oil was tried and we never looked back. in use the Teflon forms a coating on the bearing surfaces. we never burnt another hook. Teflon is a solid polymer plastic, and when used as a lubricant as in these sprays is present in minute particles. One of its main qualities is not sticking to anything, so it is hard to imagine how it "forms a coating" to protect surfaces. In reality the solid particles will lubricate with moderate effectiveness just as long as the sticky carrier gums it in place, and not a moment longer. If you want something which bonds to the metal surface and forms a long-lasting lubricating layer you need a formula containing molybdenum disulphide or similar. David |
mgj | 08/09/2012 12:11:37 |
1017 forum posts 14 photos | One of the reasons many of these products don't perfom as well as one might expect, and others seem to get them to work well, is because occasionally people don't think about what the material is doing and how it works. It is important to use them intelligently, If you have a thin type penetrating oil which disperses water out of a crack. (WD, 3 in 1 and many others) thats grand, but the water hasn't gone away (as a matter of principle) Its simply moved elsewhere. Eventually the oil will float (depending on evaporation rates of the wateretc etc.) So the trick, in watery conditions like the bore of a steam engine, or tools in a poly bag full of damp air, is to dry the water off and respray. (With say a loco, its easy - pump the stuff in, spin the wheels a few times, and then respray, and no risk of a cylinder full of heavy oil creating a hydraulic lock next time. ) ------ Again, I think it most unwise to say what will or won't stick to what, not unless one actually knows the subject. The chemists these days really have their act together, and just because a material is ostensibly slippery, it doesn't mean to say that it won't stick to something, using electrical bonds and the like. For instance preservative greases can look the same as any other grease, but have very poor charactristics under load. Some oils can be very good at rejecting water, cling to surfaces but reject small particles, and not be made of "oil" at all, but for example glycol. So generalisations can be - misguided or possibly just out of date.
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Russell Eberhardt | 08/09/2012 15:06:08 |
![]() 2785 forum posts 87 photos |
Posted by Bazyle on 08/09/2012 00:16:23:
One trouble with oil on tools is your hands then get covered in it.. When I started metalwork lessons at school (in 1961) we had to rub a few spots of oil onto our hands on entering the workshop to avoid rusty fingerprints on tools and machines. A practise I still stick to and I have very little problem with rust here. Russell |
John McNamara | 08/09/2012 15:21:47 |
![]() 1377 forum posts 133 photos | Hi David Littlewood If you Google "tribology Teflon oil" you will find many references to Teflon added to oil to enhance its lubricating properties. The rotary hook and bobbin case of a sewing machine have highly refined ground and superfinished bearing surfaces. Having had several quite costly failures under industrial conditions, not counting the machine down time, we were at a loss to solve the failures trying several different lubricants. molybdenum disulfide, or graphite were out of the question, they leave blackish stains, as was any mineral oil that was not water white. Much of the work was white linen backed. The sewing industry has specialised lubricants for this very purpose. Unfortunately in this particular application driving a machine with CNC continually running maybe 50 minutes in the hour allowing for work piece changes was too much for the Sewing head design. The rotary hook bearings overheated and failed. Using the Teflon oil they ran cool and did not seize.
If you Google the following you will see the part.
I beg to differ regarding your comment, It does indeed form a coating, maybe not a solid plate but a film. you can feel it on the steel surface even after you have wiped the oil away the surface is slippery. Alexander J Slocomb in his book Precision Machine design refers to a National Physical laboratory mechanical surface roughness testing machine that uses Teflon pads as bearings, in particular the way Teflon coats the opposing bearing surface with a microscopically thin coating, once this coating is built up it reaches a point of equilibrium, the transfer then slows down. the device worked to micron accuracy. All this information is hindsight; at the time we had a problem, found a solution and for many years after had no trouble with the machine. Ample proof that Teflon suspended in oil is a very effective lubricant. Cheers John McNamara Edited By John McNamara on 08/09/2012 15:26:11 |
Sandy Morton | 08/09/2012 17:16:42 |
104 forum posts | I had a cycle hiring business for 40 years and the best spray on lubricant which I ever used was Super Spray Lube. I have tried every other one available in Britain but that one was, without question, the best for cable inners and any light graphite grease for bearings. Keeping the bikes clean, dry and lightly lubricated was the best and easiest maintenance and it also works well for all of my tiny steam engined. |
John McNamara | 09/09/2012 01:58:32 |
![]() 1377 forum posts 133 photos | Hi All If you Google, Precision machine design NPL nanosurf Teflon You will find an excerpt from the book mentioned above. It starts on page 442. scroll down to see it. On my computer it was at the top of the search results list. If you know the title of a book often Google has excerpts from it, And if you know the chapter you want to review and you use keywords from that chapter Google will take you straight there. Maybe I should clarify here I am not referring to dodgy ebooks. Google does this as a marketing device to lead you to a retailer who will sell the book. So all above board. Cheers John McNamara Edited By John McNamara on 09/09/2012 02:05:08 |
Terryd | 09/09/2012 07:31:00 |
![]() 1946 forum posts 179 photos | Hi Chris, teflon lubricantd can offer both excellent lubrication (without the problems of contaminant collecting properties of oils and greases) as well as rust prevention. You just have to choose the right one. See here for example Regards Terry |
David Littlewood | 09/09/2012 12:04:10 |
533 forum posts | John, You are putting words in my mouth instead of looking carefully at what I said. I agree - and never said otherwise - that PTFE has a very low coefficient of friction, both with itself and with metals; I also said it would lubricate as long as it stayed on the metal. What it will not do is bond to the metal and form a long-lasting coating; it will stay in place only as long as its carrier liquid keeps it there None of the references you cited say anything to counter this. Yes indeed, it is possible to bond the polymer to steel, but only by activating it with same fairly hairy reactive compounds. Nothing which would be put in a spray for public use comes close to this level of reactivity. See for example **LINK** In any case, the question was about rust prevention, not lubrication - not that this discussion is not of interest! David |
Jeff Dayman | 09/09/2012 16:46:48 |
2356 forum posts 47 photos |
"Incidentally Geoff, I didn't think that an IC engines rings depended much on oil. A lot of IC engines have oil scraper rings precisely to remove (almost ) all of the oil from the bore.
What happens when you use the choke/ECU on start up, if the rich mix doesn't wash the bore clear, or nearly so?" Item 1- you obviously don't understand piston ring / upper cylinder lubrication - suggest you do some Googling. Item 2 - If you choke an engine to the point of washing the rings and bores with gasoline, it is very unlikely it will start because the plugs will be soaking wet. This is my last post on this, won't feed the troll any longer. My original reccomendation to the OP was fogging oil or gear oil for preventing rust on tools, and that is still my suggestion. Good luck. JD |
bricky | 09/09/2012 19:34:01 |
627 forum posts 72 photos | Hi Having worked outside in the building trade for 50 years ,rust was a problem on any tools. These were left on site in tin huts on my firm so you can imagine the condensation problems. An old joiner told me to use long oil,this is any oil that is held between finger and thumb and forms a long drip.This kept his tools free and mine also over the years.I have continued to use chain saw oil on any machine surface in my workshop,it works for me. Francis |
Stub Mandrel | 09/09/2012 21:45:53 |
![]() 4318 forum posts 291 photos 1 articles | Finish line teflon grease isa wonder cycling product that works on many other trhings too. It has the advantage of being white.
I have a large tub, somewhere. It was spotted about six months ago, but it seems to have evaded capture Neil |
Steamshy | 10/09/2012 07:32:45 |
38 forum posts 2 photos | WD40 works well on your sore joints and knees, Just spray and rub in, works for me. Andy |
Clive Hartland | 10/09/2012 07:51:27 |
![]() 2929 forum posts 41 photos | There are some PTFE sprays that incorporate what smells like Cellulose thinners and it breaks up plastic seals and rings ! I used it on an air rifle and it destroyed the piston seal and it cost £18 for a new one. Regarding the application of PTFE onto surfaces, as I quoted in an earlier post that I sprayed a solid type PTFE onto my woodwork saw table and it was just like clear cellulose varnish, it has been in place now for some 12 years and is still good. It certainly aids the through put of wood through the planer . One product I have always avoided is the Silicone sprays as they cause more problems than they are worth, get it on a windscreen or wipers and you will have to clean it off with a mild abrasive. I remember it was used once as an additive for 2 strokes but it soon disappeared off the market. Clive |
Lambton | 10/09/2012 09:07:14 |
![]() 694 forum posts 2 photos | Genklene was the ICI trade name for trichloroethane (which is different to trichlorethylene). Both are good solvents for cleaning grease and dirt from metals but have no anti-corrosion properties. Genklene has been banned for many years but not for reasons of workshop health and safety. It was banned as an ozone depleting material under the Montreal Protocol of 1987. In fact Genklene was a much safer solvent than trichloroethylene as it is less toxic and does not readily decompose the hydrogen chloride which often condenses on steel items as a very thin layer of hydrochloric acid promoting surface corrosion. In the late 1980's we had to change our 3 vapour degreasers from using Genklene back to trichloroethylene. Despite the degreasers being maintained in tip top condition after humid weekends we would be confronted with extensive surface corrosion on all the steel components anywhere near the degreasing tanks. This never happened with Genklene. The staff quite rightly asked what the fumes were doing to their lungs if they rusted steel. |
Gordon W | 10/09/2012 10:01:58 |
2011 forum posts | Chain saw oil was very good as a rust preventer, it is now bio-degradable so I have no long term experiances. Would guess it will not be good. |
PekkaNF | 10/09/2012 10:52:41 |
96 forum posts 12 photos |
Posted by Gordon W on 10/09/2012 10:01:58:
Chain saw oil was very good as a rust preventer, it is now bio-degradable so I have no long term experiances. Would guess it will not be good. The "Bio" chansaw oil is fine to make firewood for bread baking, but it will gunk chainsaw oil pumps and works if left unused for few months. Don't leave it into chain saw over winter. It's almost impossible to clean it off from oil pump if left there way over winter. My guess is that "wegetable oil" will oxsidise bit like a linseedoil and if that is what you want for gardentools good, but I would not wash engine insides with it. PekkaNF
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KeithL | 06/10/2012 18:16:18 |
1 forum posts | I've always found WD-40 to be an excellent rust preventor, IF you use it properly, ie coat whatever (usually spray) and then LET IT DRY!, it's properties are completely different from the "wet" form.
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