A Driving Instructor's Blog


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Smearing windscreen in rainI’ve mentioned this in the smearing windscreens article, but winter is the time of year where it gets wet and cold (well, certainly wet), and along with the salt spreading a lot of crap gets thrown on to your glass and builds up into a nasty film that doesn’t easily wash off.

I’m always surprised that some people – including driving instructors – only put water in their wash bottles. And they try to justify it! But water on its own simply does not have sufficient wetting properties to attack oil, wax, and grease stuck on the glass. You know when it’s there, because you get that mosaic pattern left behind when you wipe in the wet.

You need a good detergent to clean off oily deposits, and a small amount of alcohol to assist with wetting. Alcohol also functions as an antifreeze when present in higher quantities, so whereas water will freeze at 0°C, a proper screen wash solution containing alcohol will freeze at a lower temperature depending on how you mix it – as low as -9°C.

You can buy two types in the stores – concentrated, or ready-to-use. With the former, you dilute it yourself depending on the weather outside, and with the latter you have to buy the correct type (they do ‘summer’ and ‘winter’ mixes, with the summer one containing very little alcohol). In most cases, the ‘concentrated’ stuff can be used neat and will protect to between -6°C  and -9°C depending on the brand. Some types claim as low as -20°C, but these are specialist ones and they likely contain other chemicals, since alcohol alone to provide that level of freeze protection would be quite dangerous because of its flammability.

The price of typical concentrated screen wash varies from about £5 per 5L in summer, to about £8 in winter (when you need it the most). The ready-to-use stuff is similarly priced, even though it is more dilute – so you are paying for water if you buy that. In a bad winter, with lots of rain and slush, I can easily get through 5L of washer fluid each week. I use less in summer, but over a year it can still mount up.

If you’re going to buy it, my advice is to stock up in summer when the prices are lower, and only get the concentrate so you’re not paying someone to dilute it for you. You often get BOGOF offers in summer.

However, it can be cheaper to make your own, and it is certainly more convenient. I got the idea when I had a freeze up one time (I was late switching to my winter mix in the first of the two cold winters we had about ten years ago), and solved the immediate problem by nipping into a hardware store and buying a bottle of methylated spirits. Adding that to my wash bottle depressed the freezing point and I was running again within 30 minutes. So then I thought why not make my own?

Washer fluid essentially needs to do two things:

  • clean
  • not freeze when it gets cold

It’s basically just a mixture of alcohol and water with a bit of detergent. And some smelly stuff and dye if you are going the whole hog with it.

For a normal screen wash, the recipe below is what I now use. In a 5L bottle, I place the following:

  • 10g Alcohol Ethoxylate
  • 50g Butyl Glycol
  • Ethanol
  • Fragrance
  • Colouring
  • Water to make up to 5L

The amount of Ethanol depends on the temperature you want to protect down to. To protect to around -2°C, 250mls of Ethanol is all you need (this is my Summer mix, since Ethanol also acts as a wetting agent and it helps to get rid of tree sap). To protect to -4°C, you need 500mls of Ethanol, 750mls protects down to around -6°C to -7°C, and 1L protects down to -9°C. Any more Ethanol in the mixture than that and the solution (especially its vapour) becomes potentially highly flammable. I adjust the amount depending on how cold it is, but I switch to at least 500mls around November each year.

Surprisingly, the water you use is quite important. Tap water is likely to leave water marks on the glass when it dries because of the dissolved salts in it. For many years, I used boiled rainwater, but these days I use the condensate from a home dehumidifier.

I buy Alcohol Ethoxylate and Butyl Glycol from Mistral Industrial Chemicals. At the time of this update, 1L of Alcohol Ethoxylate costs £15 and 1L of Butyl Glycol costs £16.99. The total value of these in each 5L batch of my screen wash is therefore just under 16p.

Ethanol is the most expensive ingredient. I currently buy mine from Liquipak. To keep the overall cost down, I buy 20L at a time, so a batch of my screen wash set to protect me to -9°C would contain Ethanol to the value of £4. A Summer mix would contain about £1’s worth.

I latched on to Alcohol Ethoxylate and Butyl Glycol from reading the Safety Data Sheets from various manufacturers of commercial solutions, and worked out a recipe from there.

A brief aside…

Some years ago I was having major problems cleaning my windscreen on new lease vehicles when I received them. There was something on them that gave the mosaic effect in the wet, but absolutely nothing would get it off.

Eventually, I found that Sugar Soap would. Sugar Soap is used by builders and decorators for degreasing walls and paintwork before painting, and I found it did remove the stubborn film from my windscreens.

Then, a few years ago, I was snooping around the forecourt while my car was being valeted at a hand car wash. I was intrigued by all the things they sprayed on the car which got it sparkling clean, so I wanted to find out what they were using. This was when I discovered Traffic Film Remover (TFR).

I tried using Sugar Soap in my screen wash, but it left a heavy residue when it dried. For several years I used TFR, which was much better (and very effective), but it still left streaks when it dried which I wasn’t happy with. This is why I came up with this latest recipe.

However, if your windscreen picks up a lot of wax from car washes, and other residues from the road, screen wash alone won’t completely remove it. In fact, you can completely degrease your windscreen in the visible areas, but it you leave even a trace of wax on the wiper blades or – worse – in the space where they sit when they aren’t wiping (it gets pushed down there and acts as an ink well), it gets spread pretty quickly back on to the main area of the glass.

An occasional deep clean using Sugar Soap or TFR is still a good idea, therefore. You can get Sugar Soap on Amazon, or at the local Screwfix depots and such like. You can get TFR (among other places, including Amazon) from JennyChem. And if you do decide to order directly from JennyChem, use the discount code BAYJC8628 to get 5% off.

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Alcohol Ethoxylate and Butyl Glycol are the same agents used in commercial screen washes. They are relatively non-foaming, and are designed to attack the kind of stuff you get thrown up on to your glass while you are driving. Don’t try using Fairy Liquid or other household detergents – you’ll have bubble blowing down the street, and it doesn’t work for this purpose anyway at the concentrations it is intended to be used at.

Personally, I make my screen wash fluid ready-to-use as I need it (I make three or four batches at a time and just keep them on hand, making more as required). In summer, I use the minimum amount of Ethanol, and in Winter I just up it depending on how cold it is outside based on those freezing points I mentioned earlier.

As for the fragrance, I found a concentrated Apple scent specifically for car detailing applications like this. It is manufactured by Koch Chemie in Germany, and is called Duftstoff Apfel. If anyone wants to know where to buy it, drop me a line using the Contact Form. And the colouring I use is just three drops of food dye.

How can I prepare for cold temperatures?

Use common sense. If it’s warm, you don’t need a low-temperature screen wash mix, since the higher alcohol content is just a waste of money. But you do still need decent cleaning power for the bugs and tree sap you’re going to get. However, if it gets very cold, you don’t want a freeze-up, so be ready to alter your mix accordingly.

For the recipe I have given here, assuming you have made it to protect down to -6°C to -7°C (750mls Ethanol), you can dilute it 1:1 or 1:2 with water and it will still clean your windscreen. As I say, I make mine as I need it, so I always have the full detergent effect.

Can I make it with more alcohol in it?

Yes, but be careful. Ethanol is flammable, even in water mixtures. On its own, Ethanol has a flash point of 14°C (that means that at that temperature and above, a combustible vapour exists above it that can easily be ignited). A 10% solution in water has a flash point of 49°C, which is much safer. A 20% solution has a flash point of 36°C, which is still safe unless you store it in a very hot place. A 30% solution has a flash point of 29°C, and this is quite likely to be encountered in hot weather. My advice is not to exceed about 20-25% of ethanol.

Do not carry a strong Winter mix in your car in Summer. And definitely do not carry significant quantities of neat Ethanol at any time.

Can I use isopropanol instead?

Also known a Propan-2-ol, 2-Propanol, and Isopropyl Alcohol (IPA).

Short answer, yes – but only if the it’s a few degrees below zero. IPA has a lower flash point than ethanol, and any solution above 20% is potentially risky. IPA also has a very distinctive smell.

Can I use Methanol?

I’m just going to say no. It’s poisonous even in small quantities (it can make you go blind), and could be dangerous if inhaled regularly, so for that reason you should not use it.

Can I use methylated spirits?

Usually, this contains methanol as the denaturant – though sometimes other chemicals are used. It also has a strong smell. Apart from the time I used it in an emergency, I would advise against it. However, if you can find ‘denatured ethanol’ or ‘denatured ethyl alcohol’, and can be sure it doesn’t have methanol in it, that would be fine. It’s usually (not always) the blue stuff that contains methanol.

Can I just use water?

Water on its own is no good. If the temperature falls, it will freeze. Even if it doesn’t freeze in your main washer bottle, it will in the pipes and at the nozzles, and freezing water is quite capable of splitting pipes or closed containers. Attempting to use your screen washer pump if there is no liquid water inside could burn out the motor.

Water alone doesn’t clean many things off the glass – it won’t touch oil, grease, or squashed insects, and it will struggle with tree sap.

Remember that if you are driving without the ability to keep your windscreen clear, you are committing an offence. The Road Vehicles (Construction and Use) Regulations 1986 says:

Every wiper and washer fitted in accordance with this regulation shall at all times while a vehicle is being used on a road be maintained in efficient working order and be properly adjusted.

Arguably, you are not complying with this if you just use water. If it freezes (or the bottle is empty) and you drive, you’re definitely not complying with it. It is shocking that some ADIs are apparently doing this.

Can you dilute ready to use screenwash?

Of course you can – certainly in Summer. It’s not a magic potion – just a mixture of water, alcohol, and detergent. I wouldn’t dilute the ready-to-use stuff more than about 50:50 with water, though, because the detergent probably wouldn’t do its job properly.


COVID imageThere is going to be a fifth SEISS grant. A couple of weeks ago, HMRC sent out an email explaining how it would work this time.

Bear in mind that the SEISS is not – absolutely not – just for driving instructors. That important distinction makes how you interpret the email rather important.

The email makes it clear that the fifth SEISS will be granted depending on how much your 2020/21 turnover has reduced compared to previously. It also makes it crystal clear that you do not have to have submitted a return for 2020/21 (not due until the end of January 2022 at the latest) in order to make a claim.

It states clearly that your 2020/21 turnover needs to have been reduced compared to previous years in order to be eligible for the grant. If you haven’t yet submitted your 2020/21 return, an honest estimate is acceptable, and HMRC will determine how much you get based on the difference between 20201/21 and the previous year(s). Just be aware that your ‘honest estimate’ for 2020/21 is inevitably going to be what you eventually do submit, so be careful if lying comes naturally to you.

HMRC website makes it clear that if you are down by 30% or more, you will get 80% of three months’ trading profits (maximum £7,500), and if you’re down by less than 30% then it will be 30% of three months’ trading profits (maximum £2,850). This is because – as I mentioned – the SEISS is not just for driving instructors. It’s for plumbers, electricians, cleaners, nail bar owners, and all kinds of other self-employed people, etc., as well as instructors. Some of those will have legitimately traded while, ADIs ought not to have been.

I am confident that having only worked for about six weeks at a very reduced rate last summer, I will be eligible for the higher award. My turnover was down by more than 90%. However, if I’d pretended everyone was a ‘key worker’ and crammed in a lot of work I really shouldn’t have been doing last year (whilst claiming ‘hoax’, and boasting about not wearing a mask), then I’d have been at the lower rate – if I was eligible at all. If anyone out there did that, then I wish them well in their dilemma over what to do next – and I’d love to be a fly on the wall watching them complete their 2020/21 self assessment.

But for me, I have no such dilemma. My reduced workload is absolutely transparent. I typically do around 1,100 hours of lesson in a year, but in 2020/21 it was down to about 70 hours – a 95% reduction. And all as a result of following advice, taking this seriously, and not trying to be a smart ass.

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A downward trendAll was going well. Then, last Monday, a pupil texted me to say he’d had to go into isolation because someone had tested positive at work. He actually had COVID last year. Then, the following day, I gave a lesson to a pupil who had been to watch one of the Euro 2021 matches at a pub with work colleagues (in spite of my warnings about the risk). He tested negative for the next three days, then last Friday informed me he was now positive.

I shit myself, and have been frantically doing lateral flow tests everyday since. He is unwell with it, and he’s now informed me his missus is also COVID positive.

Then, last Saturday I turned up to a lesson and the pupil didn’t come out as he usually does. I texted, and he immediately replied he’d just found out a family member was positive, and the whole family had to isolate. The same day, another pupil who I was planning on visiting to help with her theory test texted me to say she’s had to cancel the test because her year has been sent into isolation at school because someone tested positive.

Then, yesterday, a pupil who had a lesson booked for tomorrow texted me to tell me he’s tested positive. He questioned why I said next week’s lesson would be off, too (he didn’t have a clue about quarantine periods, and the timeline prognosis if symptoms develop). Also, the first pupil contacted me to inform me that his last day of quarantine is the same day of his driving test this coming week (which was a moved test anyway, since he had COVID last year when it was originally scheduled for), so we’ve had to cancel it again, and unless we find another cancellation somewhere, he’ll have to do his theory test again, because the nearest dates are the end of December.

And finally, I turned up for a lesson today. I’d just stopped outside the house when the phone rang, and he told me he’d been pinged by the NHS app and had to isolate (and he had another lesson tomorrow). Yet more confusion, because he said it’s ‘two days’, and apart from the fact I wasn’t aware of anything under ten days being a quarantine period, there’s no way he’s getting in my car unless I’m sure he’s negative.

And to add insult to injury, two more cancelled lessons for today claiming feeling unwell. Funny how the nice weather does that to people (it always has done, so I’m wise to it) – but now I can’t take the chance and pick them up over it, any more than I can moan at them not telling me sooner (though the two who did that say they’d only just found out).

So the old diary has taken a beating for the next week.

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Monty Python GumbyRecently, I mentioned that when the face mask rules were due to be scrapped on 19 July, I hadn’t yet decided how I was likely to proceed.

Since writing that, I did decide how I was going to proceed based on one of my pupils coming down with COVID, and three others having to isolate, all in the space of a few days. I have been making it clear to all of mine that I will still expect them to wear face masks.

On my last lesson today, after relating all this to a pupil, I explained that me wearing a mask gives him at least a very small amount of extra protection if I am carrying the virus, and him wearing one gives me the same small amount of extra protection if he is. And any extra protection is better than none at all. He wholeheartedly agreed, as have all the others – even the one whose mother is a complete nutjob anti-vaxxer.

But when I got home and checked the latest news, I saw that face masks will still be advised in indoor settings and enclosed spaces in a U-turn by the government.

There are quite a few driving instructors out there who are as intelligent as a Gumby, and who have spent the whole of the last 15 months or so assuming the pose in the picture above and boasting that they’re working during lockdown, not wearing masks, not asking pupils to wear masks, and doing bad sums along the lines of half an orange plus three quarters of a lemon is equal to six onions (because they saw it on a nutjob channel on YouTube or Facebook and liked the sound of it). The previous news that face mask rules would be lifted provided them with an opportunity to go all Gumby, and tell everyone pointlessly yet again that they’d never worn them.

So I guess they will still continue to break the rules and show how unprofessional (and stupid) they are.

The same Gumbys are also on a rant right now about how car parks at many DVSA test centres have alternate bays coned off as part of social distancing measures. Does that mean cars can catch COVID, they ask, as they push the warped agenda they’ve tried to disseminate for the last year.

The spacing is so that those getting into and out of the cars remain distanced from each other. You have to be really stupid not to realise that. But as I say, these are driving instructors with issues we’re dealing with.


Flat EarthIt was announced today that from 16 August, those who have had both COVID vaccinations will not have to isolate if they come into contact with an infected person.

I notice that social media is still fairly overflowing with flat-earthers in the allegedly ‘professional’ ADI community proudly trumpeting that they’ve never worn a mask, and nor have any of their pupils, so the change in rules in a couple of weeks about masks won’t affect them. In case you forgot, let me just remind you what I’ve said before. That they are complete twats.

I wonder how these same specimens will do – due to their similarly stupid conspiracist views about the vaccines and whether COVID even exists – if they subsequently are supposed to isolate after 16 August? If they don’t, they’ll be breaking the Law, and if they insist on bigging themselves up on social media every five minutes (as is their wont), the Registrar might take a very dim view of their status on the Register. Frankly, if they did fall foul of that, my feelings would be along the lines of ‘serves you right, and good riddance’. After all, they are almost certainly a part of the reason all of this has gone on quite as long as it has (they’ve helped spread it, for a start).

Strong evidence is mounting that the vaccines are preventing deaths. Last year, with three noticeable spikes in infections, the death rate increased approximately 3-4 weeks later. That was when we had no vaccines. However, during this latest spike in infections, the level at which an increase in deaths subsequently occurred last year was surpassed right at the start of June. And death rates have not risen significantly at all after five weeks (fingers crossed they don’t, even though today’s figure is a little worrying). The only difference is the vaccine.

As for masks, I find it incredible that there are still people out there who believe the mask protects the wearer. It doesn’t, and never has. The mask is for the benefit of others.

I haven’t decided yet how I am going to deal with masks when the requirement for them ends in a couple of weeks. I am doubly-vaccinated and careful, of course. However, my pupils collectively (on average) go to school and go out and get pissed whenever they feel like it. Some of them have flat earth mothers who ‘don’t believe in’ the virus, or who are anti-vax/zero knowledge. So the risk to me is still there. I might decide that I still need protecting from them – it depends on how the numbers go over the next fortnight.

One asked me today what I would do. I explained what I just said, and she agreed. And another one later also fully understood. Any who don’t can find another instructor.

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