pressure gauge

[S5 modeller]

Hi chaps.

I am setting up my compressor in my shed. I want to get a pressure gauge I can fit inline, so I can get the pressure I want. I have an analogue gauge, but it isn't very accurate below 40 psi. This is not very helpful as my compressor only outputs 40 psi max.

Can I get a digital gauge? Thought this might give me the accuracy I want.

Could I repurpose a car oil pressure gauge? It has a pipe connection on the back, so I thought I could connect it via a tee piece inline between my compressor and airbrush. Would this work?

Alternatively could I use a digital tyre pressure gauge?

Thanks for sticking with me through this rambling post.

Matt.

Edited April 9, 2014 by S5 modeller

[Breaker]

When you say a pressure gauge, do you mean a regulator? Something that you can adjust to choose the pressure that the airbrush works at?

[bzn20]

What is your current Gauge range 0 - 100 or more?

When you have a system that's got a 40 PSI max. You want a gauge that's nearer to the operating pressure (but not too close). So you want somewhere IRO 80 PSI. To close to the system pressure and the gauge is close to being on the limit all the time which will weaken it. It also gives you a better view of the individual PSI divisions.

An analogue gauge is good enough, IMO.

[S5 modeller]

The gauge I have at the moment is a 0-120 psi.

As you can see, the lowest division on the psi scale is 10, and it is non too accurate. I got the gauge from work and if cost nowt, but they didn't have a lower range one.

Would the idea of a digital one work though?

Thinking of something like this.

http://m.ebay.co.uk/itm/161169209834?nav=WATCHING_ACTIVE

Edited April 9, 2014 by S5 modeller

[bzn20]

You would be better off with a "lower range" gauge for the reason you gave. Digital isn't more accurate than an analogue. Its easier to read but its like watches you have to read a digital but a glance at an analogue you know the time in a blink. If you're happier with digital it will have confidence and something else not to worry about!

I've just seen that gauge on ebay. How will you power that? Haven't you got a pressure regulator? Personally, I would get a 0- 80 PSI analogue gauge and making sure the divisions were easy to read off.

Edited April 10, 2014 by bzn20

[S5 modeller]

Not got a regulator yet, but on the look out for one, plus a water trap.

[Hotel Papa]

Not got a regulator yet, but on the look out for one, plus a water trap.

These usually come with a gauge in the sensible pressure range.

And there really is no reason to assume that digital is better. In this case it's just more complex, needing power.

Edited April 10, 2014 by Hotel Papa

[bzn20]

Yes get a regulator / water trap you'll need one!

So how do you control your air pressure without a regulator at the moment?

Edited April 10, 2014 by bzn20

[S5 modeller]

Not been using my airbrush really, and have used the dreaded canned air for the bits I have.

[rotorheadtx]

I'm using a re-purposed tyre pressure gauge. Needs an adaptor fitting, but cheap as chips, and 0-50PSI range.

[Abacus]

Replaced my gauge, reading up to 30 psi- far easier to read and regulate.Selection here (no connection)

http://www.ebay.co.uk/itm/50mm-Air-Pressure-Gauges-Multi-Listing-/121196050228?pt=LH_DefaultDomain_3&var=&hash=item1c37d8f734

[AngloSaxon]

If you do go the analogue route, I would recommend considering paying the slight extra for a glycerin filled gauge. The glycerin dampens any potential vibrations and helps give a much clearer reading as well as helping to reduce the wear on the internal mechanicals of the gauge, making it last longer.

Mike D.

[S5 modeller]

Ok, so general concesus leans towards analogue. I just think that they are a bit hit and miss, the markings are quite widely spaced, and there are no sub divisions on them.

I just thought with the digital you know what the pressure is, not somewhere between, say, 15-17 psi.

The one I was looking at could be powered off a 12 volt mains adaptor without too much trouble.

Will it work just connecting it inlibe with the air supply?

[bhouse]

Digital is not inherently more accurate. The best most digital gauges/meters will achieve is +/-1 least significant digit. So in the case of a gauge with a 2 digit readout showing 15, the pressure is probably between 14 and 16psi - assuming it's properly calibrated!

For judging finer divisions, an analogue gauge with a suitable scale is hard to beat.

[S5 modeller]

Fair do's, but it will be no less accurate than an analogue gauge that is subdivided in units of 2, as most are I have seen, and a big gap between each subdivision.

Maybe you can get one with a fine scale on it, but you will be delving into the realms of precision gauges calibrated for inspection use, and out of the price range of the hobbyist doing all this for a bit of fun at minimal outlay.

I just thought the backlit blue pressure gauge looked cool.

Theoretically, would it work?

[bzn20]

If you go to Halfords/B&Q/ you name it, there are racks of cool looking tools I wouldn't buy with your money. Don't get the wrong idea to that comment. There are cool tools around that don't look flash or gimmicky but they last, do the job they were designed for and aren't always the cheap option. I've got 5 tool boxes full of 30 year old tools that haven't worn out. Gauges included. Saved me a bomb in replacements.

As for the theory, yes it would work but why do you want an bunch of wires to connect up. I bet 99.9% of compressor owners have analogue gauges. That's the best advice I can give you.

[mollythedog]

I would agree 100% with the advice being given here,FWIW, but if you don't take offence,I think you might be getting fixated with the gauge. In reality,it is nice to glance at the psi once or twice,but it is the regulator that controls the output of the compressor.Like an engine with a rev counter,it is nice to have one,but it is the throttle,and the feel of what is happening that tells you more.

Your compressor gives you a stock of compressed air,it is the regulator that controls the amount of air going to your airbrush,and it is the consistency of the paint/air pressure that decides what comes out of the nozzle.

I don't actually know the exact air pressure that each paint type works best at in my set up (I use both enamel,acrylic, and cellulose in several airbrushes hooked up to the same compressor) but a simple mark on the red regulator knob,with a marker tells me its position at a glance,without having to see any gauge-the pressure switch inside trips when air pressure drops and the compressor gets on with recharging it without my help.

A bit of experience with your set up will tell you what is the best pressure for the paint you use,depending on what you are trying to do (eg priming instead of an intricate camo job) and it will come with use.

By all means fit the digital gauge if you want one,but a regulator and water trap would be my first buy. And yes,I have an analogue one on mine,though it has been a long time since I looked at it.

Good luck with it,whatever you choose.

mtd

[Duncan B]

I also think you are fixating too much on the pressure side of things, ask most people what pressure they spray at and the answer will most likely be along the lines of "approximately X to X+5 PSI". They are not being secretive or forgetful, it's just that the exact pressure down to the last PSI isn't that important. As MTD says, above, its more about the feel and how the paint looks. I rarely alter the pressure setting on my compressor at all, it's set to somewhere about 15 PSI and that is where it normally stays for everything.

Duncan B