Rust !

How do people protect their tools from corrosion in a non insulated workshop ? I used to have my lathe and mill at my work and never had a problem. Now with this cold weather, my mill bed turned brown overnight ?

I’ve now covered them in BBQ covers, but does anyone have any other suggestions ?

Hydraulic oil

Easy way is to buy a dehumidifier, failing that WD40 or Duck Oil sprayed regularly. You may also want to look at ACF50, it is a very good anti rusting fluid, not cheap but it does work. Usual disclaimer applies, just a satisfied customer.

WD40 - plenty of it.

Also keep it dry.

Plus one on the ACF50, Yes it's expensive,but instructions do advise to apply sparingly, so it lasts fairly well.

Popular with Bikers, Think the advertising claimed it was developed for aerospace industry....a slightly more safety critical area than considered here.

For the more thrifty pretty much anything oily should do the job.

Didn't gardeners used to oil up their fork & shovel with linseed oil for the Winter?

In my younger days, my ridden through the Winter motorcycles used to retain a shiny engine casing by virtue of the fact i could only afford old clapped out ones that leaked oil.

If you do a forum search on rust, heating, and a few other suitable words you will find at least 3 threads covering this topic in the last month,.

To be honest this crops up regularly, my main workshop is an old cow byre so that rules out dehumidifiers and electric oil filled radiators,so when I've finished using the lathes/milling machine or any of my machines I spray them with duck oil or wd40 then cover them with a heavy velvet curtain and a shower curtain on top which apart from being waterproof is thin and covers well, and for heating I have a pot belly stove with a home built heat exchanger which blasts the heat out and I just light when needed, it won't heat the whole workshop but it does keep me warm, that's my take on it and it works for me, everyone has their own ideas of course.

I used to use a 25w light bulb under the bed of the lathe with the cover on. Seemed to work quite well. Its all about having enough heat to keep it above the dew point.

Some use the heating elements like what is used for wrapping around the water pipes to stop them freezing.

Neil

I have insulated my shed with reflective silver bubble-rap,which is a cheap effective option and I have a blow heater which switches on and off at above dew point. Oil all the exposed tools etc and cover the machines over, this has been a cheap option for me and works, no rust.

Bob

Insulation, draught-proofing, dehumidifying and heating is all you need to organise, to avoid rusting.

Draught-proofing is cheapest, insulation is a one-off cost (saving money going forward), dehumidifying reduces the water available to condense and provides some heat energy (more with the desiccant type than the compressor type - but efficiency of these machines varies with temperature). Heat, to avoid dropping below dew-point, at least, is also a necessity - but at a cost as it is continually being lost nearly all the time throughout these colder months. Heat should not be derived from heaters which release water vapour to the workshop atmosphere.

As you say your workshop is uninsulated, your problem will not really go away until that is improved. Insulating and warming individual machines seems to be your initial priority. Protective coating of surfaces,, while effective in the short term, is not really a satisfactory long-term solution, IMO.

Currently, in this latest milder period, my workshop is costing under 8p/day for complete rust avoidance. No other heat input than from the dehumidifier, which runs for just an hour each night, unless I need extra warmth while in situ. As I’ve not spent very long in there at a time, recently, the extra heat input has only amounted to about half an hour. It’ not dropped below 10 Celsius - maybe 9 - recently.

My heating input (apart from the regular 375W used by the dehumidifier) is from a maximum 4.2(?)kW heater but running at approx half power. While my machine working surfaces are, of course, lightly oiled, I take no particular further steps to protect hand tools.

Do not use WD-40!

Its protection is very short-lived and its best alternative use to its intended water-dispersant as its name shows, is for flushing old lubricant out of bearings!

It is just a very thin oil diluted with white spirit.

You are best using ordinary lubricating oil or grease, or a protective spray or brush applied oil, like 'Duck Oil', made for such work. Some types slowly dry to a protective film that needs be wiped off with a cloth moistened with white spirit. These protectives are used on the machines imported by firms like Axminster and Warco.

'

For longer use on static surfaces, petroleum jelly ('Vaseline' and lanolin are tried and tested materials. An old way to protect wire-ropes is to soak them in a solution of lanolin in meths or white spirit; but note this is not a lubricant. It is a water-proofing that also has the advantage of being safer on the skin than mineral-oils (it was once used for protecting the steel-wire ladders used in caving).

'

Covers? I am not sure if this is always wise as an impermeable barrier can trap water-vapour under it. I leave my machines uncovered but lightly oily, and they seem fine; in my unheated but moderately well insulated workshop. Unprotected steel seems to rust only a bit less in the house!

.

Samuel Haywood mentions linseed-oil on garden-tools. Any vegetable oil would be entirely appropriate there, and you could use linseed-oil for other tools, but is likely to dry to a sticky residue.

Year back I encountered castor-oil filling old-fashioned sonar transducers, where it conveyed the signals very efficiently between the active element, through a rubber diaphragm, and the surrounding water. The fluid in our cochleas, and the spermacetti and similar fatty oils in marine mammals' hearing, are the biological equivalents. Castor-oil though, has an affinity for any and every nearby surface, where it sets to a tenacious glue horrible to handle and to clean off!

I can rely on the ruler of my Starrett combination square being the first thing to rust so I use it as an early warning. However, when I missed the warnings, the impact can be so depressing that I ended up investing more in sorting out insulation etc than I spent on any tool.

I tend to wax things. Renaissance wax for for small valuable things like Starrett bits n bobs.

Initially, I used to use WD40 both as an initial protector, but also as a cleaning agent to remove the inevitable stains which seemed to occur. I also have a cloth of some description (sorry, I've no idea what it's made of) which I put over the lathe and then a folded sheet of black plastic (folded to get it down to a suitable size). Initially, the plastic was to protect against water leaks in what was then a leaky garage.

Needless to say, it was quite a messy job cleaning up and then respraying.

Ultimately, I used some small self-regulating cabinet heaters from RS Components I bolted two of the 10W versions on the inside of the lathe bed. Magic! No more rusting, and the lathe always felt just that little bit warmer than anything else. The downside? It turned out these things despite being rated at 10W, were actually running at 19W - correctly so it seemed according to the spec sheet. So two heaters, 38W in total & no rust.

Since then I've added one to a large lump of 13mm thick aluminium wedged in the base of my milling machine. Again, I use an old chair cover, material indeterminate but came from my mother so probably manmade, along with a thin plastic cover. Again, no rust.

Ok, it works, but, these days especially, at a cost, but compared with the otherwise mess of WD40, for me currently worth it.

Cheers,

Peter G. Shaw

It's caused by condensation, which occurs when the temperature of damp air changes relative to the temperature of exposed metalwork. In a damp un-insulated shed, temperature cycles continually with day and night and with the weather.

Condensation consists of millions of microscopic droplets of water highly charged with oxygen. The droplets penetrate into the tiny pores and cracks in metal surfaces, and Iron rusts easily.

Best answer is to remove the damp and minimise temperature cycles with an air conditioning system.
More practically, insulate and waterproof the shed, ventilating to discourage damp coming through the floor, walls and roof - all likely in a basic shed. Also avoid processes like brazing that generate water vapour. Breathing sweaty people are harder to keep out!

Various options and sub-options:

• Protect the tools. Coat everything in oil / grease / or a preservative. WD40 is good for displacing water and it provides a thin temporary protective layer. Works for mild cases, and it's not necessary to clean tools before using them. Lubricating oil provides more protection, thick oils and grease being better than thin oil, but messier! Heavy grease and protectives are best for long term protection, but have to be removed before tools can be used. Covers sometimes help, but not if they trap damp air next to the tool.
• Remove water with a dehumidifier and/or ventilation. Requires active management.
• Control temperature, either by warming the entire shed so the temperature never varies, or - cheaper - heat the tools so they are always slightly warmer than the air. Likely to be pricey, and has to be reasonably safe - you don't want faulty heater to burn the shed down in the night.

Much depends on the exact circumstances, so counter-measures that work well for some are hopeless for others.

My workshop is in an unheated interior garage, with domestic grade walls and damp-proofing. I get away with regular wipe-overs of Hydraulic Oil. Un-insulated sheds are more difficult...

Dave

Edited By SillyOldDuffer on 11/01/2023 11:05:29

The use of any heat from a flame source will cause moisture in the air and lead to rust. I have my lathe and milling machine in my garage and used to use a diesel space heater then a gas space heater both produce loads of moisture , very noticeable on the vice . It was so bad I often brought the de-humidifier into the garage to dry it out . I now use a Chinese diesel heater that blows hot air and all the exhaust with moisture is run through a wall to the outside . Result is warm garage with very little if any condensation . I still wipe down the mill and lathe after use with WD 40 then spray a light coat of oil on the beds . Seems to work ok .

The diesel heaters are excellent . Have a look on YouTube . Some suggestion of running them on old engine oil ? but that's illegal in UK so Red diesel if available or Heating oil/Kerosene is a cheaper option. Mine is a 5KW model and uses approx 1/2 lire an hour at full heat .

To get the waste heat from the exhaust some have run the exhaust through an old wall mounted radiator before exiting it through a wall. Radiator also acts as a silencer for exhaust and provides a lot of heat .

---------------------

I have a draughty unheated bare boarded lean to shed with transparent roof and flagstone floor @14ft & 8ft and I have 5 vintage lathes in there and they almost never have rust. I say 'almost' as for the first time in 20 years on the 19th of December someone posted here that their machines were soaked with condensation and going rusty overnight and lots of ME members rushed out to check and reported the same.

Apparently a freak combination of weather caused it here in the UK. I found on the side joined to the house that the machines and overhead countershafts were soaking and rust had appeared already so spent ages wiping everything down and cleaning off rust and spraying WD40. The opposite side of the shed was still bone dry!

It all largely depends on your workshop construction.

Single brick or wooden shed, the recent rain will get through the walls and condense on your colder machines covered or not.

Concrete floor without damp proofing the same thing happens and in this case the plastic covers can make it worse.

Chainsaw oil has a sticky nature and is not easily displaced by water

Here we go again with a thread that's been done to death and exhumed umpteen times.

However, let's do a few basics. Garages with or without sweating asbestos roofs, wooden sheds with walls that soak up rain like a sponge, they are all useful to counteract weather but all steel stock and tools will rust without further protection. A very thin plastic sheet thrown over machines and benches at night is first protection against falling damp or roof springing a leak, as in say, roofing felt failure. Next, either smother everything with almost any old oil incl WD40, OR, employ very low heat under at least one machine cover, to keep even damp air above the dew point. Most important. Heat will slowly escape and gently warm the general workshop and help protect everything else, depending upon the total volume. My second small mill and big bench drill and bandsaw are all only covered with large  plastic bags and unheated. I have a wooden shed, 10ft x 8ft raised on 3 layer brick wall with strips of felt as a damp course. Window boarded up, entirely encased in roofing felt to keep rain off the wooden carcase. Walls and roof heavily insulated internally. Floor solid concrete for machinery and the rest coated in black tarry substance, anti-damp. Brick walls also coated internally. Old redundant small mats and carpet tiles lobbed in layers on top. Tubular heater on rear of Myford driptray, controlled by timer, on sunset to dawn + couple of hours and a thermostat set to absolute minimum. Home made heater in protective box on small mill drip tray. Four low wattage filament bulbs wired in series on 24/7, gives very low heat and consumes very low current. Benefits of heat v oils are machines pleasant temperature to handle and no oily mucky mits! Keep all steel away from cardboard - cardboard catfood boxes used to store emery cloth strips in one and sandpaper in the other. Cardboard boxes retain damp and if made by using acid water, they WILL rust anything steel in contact, as a previous employer found to their cost! Expensive new heaters stored in suppliers cardboard boxes stored in an unheated building next to a canal. Card boxes were made with river water. Dont use gas torches, not even for a little soft Soldering. No open solid fuel burners like wood stoves. Keep all bottles of acids and alkalies outside/elsewhere, glass or plastic sealed or not. Includes things like brick or patio cleaner and toilets!

HTH

John

Edited By DMB on 11/01/2023 16:40:27

I use clip lock food containers for small tools. In one of my past garage workshops I used to cover or grease larger items like the mill table.

I use an old shower curtain to cover my lathe, seems to work ok - that's the woven, synthetic fabric sort, rather than the ones like a thick plastic bag.

Rob