Dealing with rust in the home workshop

[@protospace270]

I've had the exact problem in my shop here in the northeast US. The first thing I did was buy a dehumidifier to maintain a low humidity environment. That didn't make my garage any warmer in the winter so I fully insulated it amd installed a mini-split heat pump. This has an "away" setting to keep my garage at a constant 46 degrees Fahrenheit. Without the machines able to absorb deep cold, when I turn the heat up the machines no longer sweat and it makes it much more comfortable to work in year round. These three things have completely eliminated rust in my shop and I'm now able to comfortably work at all times of year. Another cheaper option is a better rust preventative than standard WD40. There are several out there that once sprayed on, evaporate and leave a waxy film that sticks to the metal better than standard WD. WD40 themselves makes such a product and it works alright, but I've used better. I hope these ramblings help 🙂

[@Workshopfriend]

Thanks for your helpful feedback. From your response, and the others, I can see that I am going to have to attack this on multiple fronts. I think further insulation and better moisture repellent are going to be next. Let's see how far I have to go with this! I suppose the advantage we have here is that our winters are not as severe as yours.

[@carlwilson1772]

I'm very lucky in that my workshop is an integral part of my house, fully lined, insulated and plasterboarded. It did have an up and over door like yours but I replaced it with a fully insulated roller door. Much more secure than the old door and thermally efficient. It is effectively a fourth wall. I would recommend fitting one of these if you can. My floor is concrete but fully damp proofed. I also gave it two coats of two pack epoxy floor paint. The temperature in there does not fluctuate more than 2 -3 degrees, summer or winter. I would definitely go with putting battens up on the brick walls and some form of board with insulation interposed. With sufficient ventilation/air bricks too. Then some form of heating. I think it is worth spending the time to create a benign workshop environment. For the owner as much as the machines.

[@andrewdolinskiatcarpathian]

Hi Clive. I have in the past suffered with flash rusting in the various workshops I have used. In one the problem was particularly bad. I needed to do much remedial work to prevent damp getting into the space as well as finding a substance which actually did prevent rust. WD40 never seemed to work for me. A friend suggested a silicone wax polish, and this worked wonders. However I cannot find any one who still sells it. 😢 In my current workshop I use a liberal coating of “slideway” oil, which being nice and sticky holds firm and does not quickly dry out. Another game changer was replacing my steel up and over garage door with a UPVC roller garage door. This eliminated drafts and is so much more thermally effective both winter and summer. That aside, seeing the rust that has befallen upon you makes me want to rush out into the workshop to see what might have occurred during the mild, yet damp Christmas period. 🥴

[@hullygully-3599]

I enjoyed the video as always.. so thanks for taking the time to make it. Same position here in Beverley, East Yorkshire. Will try first your garage door retrofit. 👍👍

[@johnjohnson764]

Hi There, I insulated my garage workshop many years ago. Stays warm in winter and cool in summer - no rust problems. Did all walls, ceiling, door and floor. In Yorkshire, so can get pretty cold/wet/miserable out there sometimes.....

[@Paul-FrancisB]

The U value quoted by that insulation type usually assunes that it is installed on battens with something like a 20mm cavity on either side behind plasterboard, so you get a significant contribution from the air gaps to the insulation. Even so it will be a massive help compared to bare metal. Painting the outside of the door white will help in the summer if it isn't already

[@Workshopfriend]

Thanks, Paul, point taken about the air gap. I hope the triangular gap left by the struts will help provide something of a useful air gap. I also take your point about repainting the outside of the door. It was the worst possible colour!

[@charliegould7829]

Fortunately my garage is quite dry, but it gets very cold. If I try heating it the biggest source of heat loss is the metal "up and over" so I insulated it with 1" polystyrene sheet bought from Wickes. I cut panels to fit between the various stiffeners and frame members, just like you did on yours. I used cheap silicone mastic to stick the polystyrene panels to the metal door. Not only did it make it easier to heat the garage, it also provided a good degree of sound deadening as well.

[@andrewbishop7066]

Im also in the uk and have found that wd40 doesn't really cut it the best thing I ever did was swop from water based cutting oil to oil based cutting fluid

[@stevedavey1343]

Yep, the water soluble stuff has tons of downsides. The thick dark heavy stuff is the ticket. Not great with flood or mist coolant systems though obvs. 😉

[@constantinehatzis2807]

Yes I too have exactly the same door, which I insulated with the same material a couple of years ago. But I think the most important thing is to keep humidity down. Get a good old human hair hygrometer to monitor humidity, I find the digital ones quite spurious in readings. Then get a dehumidifier, the old ones are best as they are generally more reliable, also box shaped so you can put things on top. Give it a service, you will notice it's much nicer space to work in being drier. Someone else mentioned a diesel heater. I have one mounted to the side of my Colchester. This keeps the lathe slightly warmer, and acts like a radiator. I also position lots of blocks of steel and aluminium in front of the heater to absorb lots of heat.

[@Workshopfriend]

Thanks, Constantine. It is a shame that you don't rate the electronic humidity meters/sensors. I was wondering about whether I could have automatic control of the dehumidifier/heating to save having it on all the time - or just rely on the humidistat in the dehumidifier. For me the challenge is that I go away sometimes and rust always seems to hit then!

[@constantinehatzis2807]

@Workshopfriend I think the humidistat works fine, and I'm sure a better quality hygrometer will work well. It's the cheap ones I'm not impressed with...I also appreciate older analogue technology. But what I have on the dehumidifier is a plug in timer, from midnight to 9am. I also have a constant drain so I don't have to empty it. Yes, I am also out of the UK a few times a year, so a controlled environment is essential.

[@ronkluwe4875]

Three suggestions. First - buy a small space heater that can heat your shop up. The warmer the air, the more humidity it can absorb. Second - Buy a room dehumidifier and plumb the outlet to outside the shop (likely under the garage door). This removes the humidity in the air. Third - Stop using WD40 as your rust preventative for long term. Use a specific rust prevention spray such as Boeshield T-9 spray or similar. WD40 is great for short term rust prevention but is too thin to form a long-term rust prevention barrier. If push comes to shove, a wipe down with a rag soaked in light machine oil will do a very good job.

[@lukaszkus9937]

1. Walls and ceiling insulation 2. Dehumidifier 3. Electric or diesel heater That should help 🙂

[@Workshopfriend]

Thanks, Lukas! I can see that this is going to be more involved than I first realised. I have a small gas heater but didn't use it much due to it adding to the humidity level/requiring plenty of ventilation. I assumed the diesel heater would require the same.

[@terrycannon570]

I have 2 shops. One is large 24x48 ft and inside it a 12x12ft room. Inside the room is where most of my precision machines are. I've tried everything from the expensive museum wax to Boesheild T-9 and everything in between. WD-40 repels water but at the same time is hydroscopic. Just buy a gallon can of WD-40 and after months of setting with the lid closed pour some in a clear container and you will see the water in it. Most everything inside the insulated 12x12 room stays warm enough with one 4 ft Led light left on 24/7. The other two I turn off when I go in for the night. In the open area (24x48 ) I've had the same problem you are having. During the cold months you can see the water beading up on the cast iron and will rust in just a few hours. Like I have said I have tried all the best fluids available and still have a serious problem with rust. It seems that all the medication I take causes my touch to have acid in it. In other words anything that I touch will rust right through oil. The latest thing I have tried is to remove rusty finger and palm prints with "Kroil" So far so good but the week is not over yet. Humidity has been high and temps swing from 65 degrees F in the day to low 30's at night. To my understanding this is the worst conditions. I'll check back in in a few more days and report back about how the Kroil is working.

[@Workshopfriend]

Thanks, Terry, for your detailed explanation of your experience with rust! I like the idea of your inner room for the precision equipment. Sadly I don't have room for that but, on the other hand, I don't need to try to insulate a large area. Thanks for the tips re WD-40; that it is hydroscopic seems counterintuitive! I can see that I need to look into some of the better products you, and others, have recommended. Yes, it would be good to hear feedback on the Kroil for dealing with finger prints.

[@neffk]

Sadly, WD-40 will not help very much. Something waxy is needed. Fluid Film works well for me. Some people like LPS3 but I don't like how it smells.

[@thatguyted6739]

I have a workshop over in Cumbria, inside an agricultural building. My biggest issue has been rust. We've insulated the tin roof with Kingspan sheets and I've done my best to weather proof the building, but it's starting to feel like it's not enough. I believe a dehumidifier and some kind of temperature control are needed. I also use a thicker oil than WD to protect my machines and it definitely helps. Especially on moving parts like lathe chucks where WD comes off with handling and motion. Looking forward to seeing what else you try :) all the best

[@Workshopfriend]

Thanks for your interest and comments. I would imagine that an agricultural building would be on the large side. How would heating and dehumidification work on that scale? I once stored my car on a friend's farm under a barn (ie not much in the way of walls) and after 3+ years when I returned it was in fine condition. I did the same in my dry garage (not where I am now) but the upholstery suffered. I assume that there is a balance between ventilation and limiting rapid temp change - or it is just that cars are less liable to corrosion than machinery.

[@thatguyted6739]

@Workshopfriend it's a pretty limited size, probably a little larger than your shop. The big ones all have cars and tractors stored in them currently! It's incredibly disheartening to return to find so much surface rust, even with the small amount of damage it causes.

[@peterhadfield873]

Reflextix type insulation needs an air gap (1/2 inch min) to perform anywhere near its claimed specification. Cheers

[@Workshopfriend]

Yes Peter, I am beginning to wonder if I should have thought more about how to support the insulation with an air gap? On the other hand time was of the essence. Perhaps I will have to review this when I have sorted out some of the other insulation issues.

[@philhermetic]

I had this problem before I insulated my workshop, I used 2" jablite on the walls after fitting 1"x2" tile lath to the walls @600mm centres (to match the sheet dimensions) and covered the whole with 3mm plywood with a wipe clean finish (caravan sheets) I used 3" jablite between the joists and sheeted the ceiling using the same materials. It now requires very litle heat to keep the workshop toasty warm, and Ifind my East facing (uninsulated) roller shutter doors pick up enough heat to keep the workshop fairly dry. WD40 will help to remove the rust, but also washes off the oil film which prevents it. When I went back to the workshop after my enforced holiday (2 months) there was little rust anywhere, but I do oil all the surfaces and wipe them down, and then cover the machines with a variety of old duvet covers! With your place being free standing you could put insulation on the outside, but this would entail a more durable finish sheet to cover the laths. What about a tubular heater to prevent condensation, 200 watt should suffice once the building is insulated and draughtproofed. does your up and over door have the draught strips on it? inside on the upper half and outside on the lower half to fill the gap betwixt door and frame? I have seen thin foam draughtproofing strips fitted to these to seal them. This is always a problem, and you have to ventilate as well, although trickle ventilation is sufficient. Parrafin and gas heaters release water into the atmosphere unless some form of heat exchanger is used. Warm air is the way to go, although my place is not sealed to the outside as there are gaps around the tops of the roller shutterswhich I class as "ventilation" In the meantime coat everything with light oil, and give it a wipe when you want to use it! If the walls are not cavity walls using internal insulation and a dpm is almost essential! if you look at my workshop refurb video you will see what I did in the slideshow of pics (shameless plug) Hope you get some ideas from this rambling diatribe! Phil, My week this week.

[@Workshopfriend]

Thanks, Phil. Good to have you back in the workshop! Lots of helpful hints here. I noticed your wood stove in the corner in your latest video. looked very inviting. This morning, even my hardy youngest son was finding the workshop a bit too cold! I would love to do a thorough job of insulating what is really a garage, but space is limited and internal insulation would reduce that space further. I will do whatever I can, within reason, to improved the insulation, reduce humidity, and add some heating but it may not go as far as yours! Sealing of the door is on the agenda. I already replaced the lower rotten frame with concrete. I will look into the draughtproofing. Like your workshop I would have to go a long way run the risk of not having enough ventilation! Yes, I will look up your workshop refurb video. This seems to be the link for part 1: kzbin.info/www/bejne/oGeQdqWej86Metksi=Hvhf3sWqKUcgz335 in case anyone else is interested.

[@JeremyYoungDesign]

I have a very similar situation in my workshop down here in New Zealand, with dampness, no insulation, climate etc. I've found that covering my machines with drop-cloths has really helped. I guess it stops the moist air getting to the bare surfaces and condensing.

[@Workshopfriend]

Thanks, Jeremy. You concur that covering machinery is the way to go. I wonder if the drop-cloths stopped moist air from getting to the machinery or just provided another localised layer of insulation? I have had a similar discussion with my wife about her approach to placing a cloth under the lid of the saucepan when cooking rice; she understands that it collects moisture whereas I saw it as sealing the lid.

[@RichPober]

You could put solar panels on the workshop roof and feed their output, via an inverter, into an old-style thick brick storage heater. That way you machinary would always have some level of residual warmth to minimise to amount of dew collecting on their exposed surfaces. However, such an off-grid installation would not be cheap, but it is simple to install and at least you would have a warm workshop.

[@Deebo1812]

Another vote for Duck Oil here! Dehumidifier helps but won’t deal with the swings we’ve had in Scotland this year from below freezing to 11 Deg C in a night.. nightmare!

[@markpannell4058]

I use a small dehumidifier which is amazing , another thing to consider is the floor as I imagine most garages in the uk including mine don't have a vapour barrier fitted under the concrete slab. I would think most moisture in your workshop comes up through the floor. I think even painting the floor with a two pack epoxy floor paint would help.

[@Workshopfriend]

Mark, I think you are right about the floor. I like the idea of the epoxy floor paint but it would be a lot of work to empty out the workshop - something, that if really necessary, would have to be a summer job.

[@milloons2847]

What about covering the machines with old blankets? Allows breathing but may avoid excessive condensation. The cloth will wick out excessive humidity. Easy and worth a try while going for insulation and heating in the longer term.

[@Decomid]

I use Supertrol. It’s a little messy but if you’re not using the machines for a while it stops corrosion dead.

[@JeffSearust]

I'm in Texas, 100 miles from the coast. that light rust makes me nuts. Only a couple times a year does it happen. I've got blankets to put over my machines, and we will see how this works.

[@HM-Projects]

First step is to insulate the shed, next get air circulation. I've had luck with a whirly bird on the roof. Next, Lanolin spray. Best rust protection I've used. You can wipe it down in summer / spring once the weather warms up. I've tried WD40, LPS2, LPS3, plain old way oil rubbed on everything. Lanolin does dry to form a tacky / sticky film, chips will stick to it but it's better than dealing with rust.

[@Workshopfriend]

Insulation, seems to be one of the key solutions, so will work on improving that. I have never used lanolin and didn't realise until just now that it comes from sheep and or other wool bearing animals. I assume that it has to be cleaned off the lathe ways before use. Anyway, thanks for your advice!

[@HM-Projects]

@Workshopfriend I don't use it on lathe ways, just the not sliding parts. Ways are given a coating of way oil once a week and I have a bellows style cover on them. I haven't had to spray lanolin in a while though since I installed the whirly bird for air circulation. Try LPS2, it's a bit dearer than wd40 but you can probably use it on slideways as is since it's a lubricant as well

[@HM-Projects]

@Workshopfriend and yes we have plenty of sheep down here, lanolin is cheap

[@AndyMacaskill]

Yep, Im up in Inverness, and been having the same issue with the pressure changes happening so fast.

[@christophercullen1236]

I don't know about this cold business. I live in subtropical Queensland but rust is still a problem , i spray my equipment with CRC longlife anti-rust lubricant and cover my equipment with old cotton sheets they absorbers moisture . Kit from down under

[@Workshopfriend]

Thanks, Kit. Yes, I do remember having localised rust issues in Pakistan in the humid season - usually where I had left finger prints. Thanks for suggesting another brand of anti-rust lubricant. Covering of equipment seems to be a common theme.

[@paulbyerlee2529]

I will keep it brief. Use oil not WD-40 and cover tools with an old sheet when not in use.

[@Sigmatechnica]

yeah same problem here. these are the things i have found over the years: 1) ventalation is your ENEMY. block up all vents, holes,, gaps around doors, anwhere air can get in from outside. you want NO airflow, becasue warm damp air moving about will just give it more opertunity to dump more wet on the machines. 2) WD40 everything liberaly after every use. i have never found anything that works better, even grease doesn't seem to be as effective. it's a shame they don't make a slightly thicker formulation. 3) pay attension to the wood you have in the shop as well as if you have damp it will start to go mouldy and some of those fungi can attack metal as well. MDF and manufactured woods can be bad for this, as can pine. inspect everything wooden you have in there, shelves, cupboards, boxes etc and paint them with oil based paint or varnish if they are showing any signs of mould. tropical hardwoods stand up best to damp. 4) if there are any cracks or spesific areas on the walls where damp is getting in a good quick fix is to paint over them on the inside with that gorilla liquid rubber stuff.

[@andrewbishop7066]

also cover machines with old curtains or dust sheets help

[@ACDodd]

Easy fix that requires no heating, leave machines covered in wd40 every time you finish using the machines and theirs is the big one, all your machines when not in use with an old bed sheet, this will stop rust on all surfaces. When you are in the workshop also run a 1.5 kw fan heater while you are in there, the fan heater pushes damp air over the element and burns off moisture. I also put 2inches of cellotex insulation on the back of the large garage doors, makes a huge difference differences to the temps and requires less energy to heat the workshop. I see you have put your own insulation up, it will make a huge difference

[@mikebarton3218]

Try a thicker oil than WD40. Something that clings. I use cheap engine oil. Install a dehumidifier. Install some kind of heating with a thermostat to come on during the worst cold spells. I have just such an oil filled radiator in my porch to keep my plants above 4 degrees Centigrade. But be careful: 1kw of energy for an average of half a day for three months of the year could cost you £400 or more in a year. Keep it to a minimum. Put covers on your machines. I use fire blankets because I weld in the same area and I find them quite effective but I have no experience of alternatives. Of the above, the two that are most attractive on cost vs. performance grounds are a better rust inhibitor and thick covers. Good luck with it and please do give us an update.

[@Workshopfriend]

Thanks, Mike for the feedback. Yes, it seems that WD-40 is going to be replaced with something more appropriate and I could see the heating bill getting out of control if I were to go down that route! I think some kind of covering for the larger items would be a good approach. As you say it has to be based on sound economics. I will give an update. Still plenty of cooler weather on its ways to put things to the test.

[@Florian5120Pro]

A curtain in front of the garage door could help to keep out draughts and the cold. I have that in my garage but I have a wood stove too so I can't say if it works without heating but I think so.

[@Workshopfriend]

I think the garage door is a problem. I don't have a lot of room hence trying to make the most of the space. The wood stove sounds good!

[@Florian5120Pro]

@@Workshopfriend yes the not proper sealing garage door could be the main reason. I guess you don't open the garage door often did you? Maybe you could install a more fixed type of curtain there without a rail wich takes room. That only works wenn you don't open it so often. Yes wood stoves are good but you need all things around. Supply of wood, space to store it, a chimney and so on. If you don't have all of this I would choose a diesel heater. They are now quite cheap, you can buy diesel every were, it needs not much space, produces an air steam which makes a equal heat, and you can program it, so it starts and stops automatically.

[@julianchambers8372]

Hi, thats a nice size milling machine what model spec is it.?

[@stevecallaghan3245]

Clive consider using Inox rather than WD40. Inox does not dry like WD40 which is silicone based and dries out. My workshop in Brisbane Australia is insulated and we have had three weeks of rain coupled with 35degree days and 80% humidity. I checked my Colchester last week and no rust on the machine and topped up the ways and other parts with inox

[@Workshopfriend]

Thanks, Steve. Another useful product recommendation for me to look out for. It seems that the dreaded condensation problem can strike at any time!

[@mranthonye]

Get some Aero 360 condensation collectors installed. I use 4 in my garage and I'm surprised at how much water they take out of the air.

[@philthorkildsen6714]

Heart breaking isn't it. Insulation, Duck oil and a dehumidifier 24/7 seems to be working well in my small workshop. Make sure the dehumidifier has an external drain on it though as a good one will pull an alarming amount of water in 24 hrs

[@hilltopmachineworks2131]

A dehumidifier would be a big help. I have 2 in my shop that stay on 24/7. Also there are way better products out there to use to prevent rust than WD40. Not sure if you can get them in the UK. There is SP350 made by CRC and Boeshield T-9 developed by Boeing.

[@DClarke1954]

Hmmmm..... My tiny workshop is in my 18' x 6' 6" garage. No insulation on any walls, no ceiling just open to the rafters and roof felt/tiles. No rust. Freezing cold, but no rust on my lathes or mill or saws. Where is all that damp air coming from in your case to condense on your machines?

[@jonnburton]

I have had similar problems with woodworking machinery in an uninsulated workshop this year. A few weeks back we had snow and a cold snap - the relative humidity rose to 99% in the workshop and condensation was present on all the large machines, leading to rust. I removed this from the visible surfaces and purchased some Corrosion X, a product which gets very good reports. Time will tell whether a thin film of this wiped over the surfaces (it's supposed to be quite durable) will prevent further rust. Maybe consider External Wall insulation if your garage is standalone and there is sufficient eaves overhang - this would also serve as a rainscreen ensuring moisture from rain does not penetrate the walls as well as maintaining the original interior dimensions of the workshop

[@liamkelly8684]

That will not work u need a dehumidifier I had this problem and the dehumidifier solved it

[@liamkelly8684]

That will not work u need a dehumidifier I had this problem and the dehumidifier solved it