Tyre inflators- buy a compressor or use garage air line?

ripplyuk

My old compressor has now quit. It wasn't cheap, about £55. It's a mains powered one from Ring automotive and it's lasted 5 years so it works out quite expensive per year. Also, it was a real faff to use and very noisy.

I can blow up the tyres at a garage for 20p. I don't do many miles (under 4000) so the tyres only need topped up every 5 or 6 weeks.

I'm wondering whether to buy another compressor or just to use the garage. Problem is, I know tyres should be cold, and I would have to drive to the garage. Would this be a bad idea? Is there a limit on the amount of miles?

I've also been reading various things about which are most accurate. Some say the garage ones are awful, but reviews for the portable compressors also say they're inaccurate.

Herzlos

You can buy a pretty basic compressor from about £6-10 at most bargain stores and car factors. Plugs into the cigarette lighter and runs.

Gives you a way to get air back in at the side of the road too.

Chrishazle

Don't ever believe the pressure gauge on a compressor, garage forecourt etc. Get a proper pencil-style gauge and keep it in the car!

JP08

Chrishazle wrote: »

Get a proper pencil-style gauge and keep it in the car!

And even then, keep it in it's little protective sleeve and in a place where it can't get damaged. Crud, or even getting slightly out of shape, will ruin the accuracy.

ripplyuk

I've already got one of these:
https://www.amazon.co.uk/d/Tyre-Wheel-Tools/Draper-69924-Pressure-Gauge-Flexible/B0002GV286/ref=sr_1_1?s=automotive&ie=UTF8&qid=1481799923&sr=1-1

Are the pencil type ones better?

What I'm wondering is whether by driving to the garage, and the tyres warming up, the gauge results will be inaccurate.

facade

ripplyuk wrote: »

I've already got one of these:
https://www.amazon.co.uk/d/Tyre-Wheel-Tools/Draper-69924-Pressure-Gauge-Flexible/B0002GV286/ref=sr_1_1?s=automotive&ie=UTF8&qid=1481799923&sr=1-1

Are the pencil type ones better?

What I'm wondering is whether by driving to the garage, and the tyres warming up, the gauge results will be inaccurate.

Yes they will, as air expands when it is warm, and the pressure goes up, so blow them up 2 or 3 psi extra, then when they are cool at home check the pressure, and let out any surplus air. Alternatively, blow them up to pressure, then check when cold to see how much they go down, so next time you know how much over to go.

However, it is -3 at night and dawn, but 10 degrees in the afternoon, so there will be quite a pressure variance throughout the day even if you don't drive the car.......

Stoke

I bought a digital one years ago. It's great. Been an absolute life saver. If it packs up anytime soon, I'll buy another.

droopsnoot

ripplyuk wrote: »

I can blow up the tyres at a garage for 20p.

I check mine at Sainsburys whenever I put fuel in, as long as there isn't a queue. Air is free there.


But worth checking with a decent gauge as well - I read somewhere that the garage machines are regularly calibrated, but no idea whether that's actually true and I guess it will vary from garage to garage. I also read a comparison test that suggested it's not safe to assume that a digital pressure gauge will necessarily be any more accurate than an analog one.

JP08

droopsnoot wrote: »

I also read a comparison test that suggested it's not safe to assume that a digital pressure gauge will necessarily be any more accurate than an analog one.

Gut feel on this is that, once calibrated, the digital one should remain calibrated better and be more accurate. Simply because the mechanical ones are going to be dependent on temperature, the friction of the mechanism (crud etc as well as wear) and the gradual degradation of any spring. Whereas the digital ones will be based on a piezo crystal, and therefore (I suspect) only temperature.

AdrianC

The quickest and damn near easiest way to inflate your own car tyres occasionally is something like...
https://www.amazon.co.uk/dp/B00PG1PKIA

A bike track pump.

Much quicker than a 12v ciggy-socket buzzer, cheaper, and a heck of a lot quieter.
Much quicker than a foot pump, and a lot less effort.

I've had van tyres up to 3.5bar in short order with one, without breaking into a sweat.

chrisw

Does it have to be a compressor? I use an old foot pump I've had for years. I know that it under reads by about 2 psi but other than that the readings are very consistent.