Dehumidifiers

i need one for aDouble garage. It's been pretty damp generally recently but the lathe is getting some bright orange strain of rust in the odd place. i have read all the suggestions for avoiding rust. I reckon a small duhidifier could do. Can anyone recommend one ?.

I have a Dimplex model 2000 MKOC for quite a few years and it has given great service. Much more efficient than flashier looking models. Mine is dark brown, about 14" square and about 18" high. Don't know if they still produce these but they work well if you can find one.

John

Scewfix, about £135. I have recently got a dimplex. make sure you get one with a humidistat but a 2 speed fan is not necessary. Work on sealing the doors as best you can or you will be trying to dry out the world.

The larger one wil be best. Also you can use chemical tray that you can put on window ledges around the house on each machine.

I'm still using a Curry's own brand Matsui, bought over 20 years ago to help dry out plastering.

Its ugly and noisy but works a treat.

Obviously nowadays Currys has changed name, but any simple machine will do. As David says, restrict incoming damp air as much as is feasible

Can recommend Meaco 20lt, bit noisy when on high but sucks up moisture like its going out of fashion, In my workshop I covered the walls in wood cladding and then varnished it this allows me to put up shelves etc and keeps the walls from condensing moisture also fitted old double glazed windows and a home made electric blind system that keeps anybody from looking in.

Just out of curiosity, what's your garage roof made of? Mine was rust-proofed steel, and I had terrible condensation and rust problems. A couple of years ago I had it replaced with timber topped with a rubber-like compound. The chap who fitted it also cut a couple of holes in the concrete walls for ventilators. The result has been no condensation or rust, despite the fact that the garage is within 100 yards of the Moray Firth in the North of Scotland. It was an expensive operation (over £2,000), but the tools in the garage are worth much more than that.

There are different types of dehumifiers, have a read up on them as some don't work very well in cold conditions.

If you are running any sort of small boiler, don't forget to collect all the condensate for use as feed water. No lime or other unwanted ingredients.

Bill.

Plus one for the Meaco. Mine, DD8L Junior Desiccant £150, also provides a modest increase in room temperature.

Baz and Mike have made the two important points - running a dehumidifier is pointless if there is any ventilation (designed or accidental), and similarly pointless if there is no adequate barrier to moisture penetrating the floor, walls or roof.

My first step would be to put a couple of low wattage tunsten filament lamps under the lathe, as a temporary but extremely effective measure. Next I'd look at insulation and the all-important vapour barrier on walls, floor and ceiling/roof.

Model Engineer's Workshop of November 2003 had an article on stopping rust on a lathe, Keeping Rust at Bay. It used three 50W resistors bolted to the back of the lathe. These were switched on by a temperature sensing circuit when the air temperature fell below the dew point.

I thought it a neat idea and would consider it if I had a rust problem.

JA

I help out in a small local museum and we have several portable dehumidifiers of different makes and age and all seem to work well enough. We take daily readings and aim for a relative humidity of about 45 to 55% which we achieve most of the time.

The latest two we bought were rated at 12 Litre (with 4 Litre tank) from Screwfix, when they were on offer at a about £100.00 each, they are now £130.00 I think.

I see Aldi have some on offer at £118.00 but I have no experience of them.

Hope that helps.

Regards John

I have a cemet sheet and wood workshop, lined and insulation everywhere i could get it. There is a small gap at the bottom of the door which provides a draft. I do not have any rust problems but recently bought a very cheap Aldi dehumidifer around £20. My humidity hit a peak of 95%on a very wet day but normally around 70 %. But as I said no rust on any tools/matrials left out.

Before spending a £100 or so on a dehumidifier, have a look in your local sale room, here they are all PAT tested and they give your a 24 hour guarantee. I've seen a lots for sale and they haven't made much. I've had one for at least 20 years and its worked wonders, as some one said they don't work at low temperature or mine doesn't. Insulation is the answer keep the workshop nice and warm, not forgetting the doors.John

I bought one after suffering a water leak in the house, in a big area it did not seem to work that well. In my workshop I use a fan to move the air around and no rust issues. Worst thing for rust is a bottled gas heater, worse than a hose pipe in there.

I did try a Humidifier a few years back. It was about £80 from B&Q. Lessons learned.

1. It didn't work when cold (say below 10C) but was ruthless at pulling out moisture in the house in the 18C+ range

2. It was expensive to run in the workshop, too much ventilation and the cold meant it was ineffective

Cheaper to throw a blanket over the machines and pop chucks and RT in zip lock bags. The use of resistors / low power lamps would be cheaper and more effective I think, I will get round to trying that one day.

Steve

Edited By Steve Withnell on 21/11/2015 20:14:58

As has been suggested cover the machines and run a low wattage lamp in the tent formed by the cover.

A dehumidifier in an uninsulated and unheated workshop is just throwing money to the supply company.

Emgee

In the UK it is not often below 4c on average so some thermal mass inside an insulated building will work most of the time, Once the humidity is reduced it will turn off so the average consumption is no more than the heaters suggested and protects all the loose stock material etc.

Edited By DMB on 21/11/2015 23:02:59