air compressors

I am nearing the completion of a Stuart Victoria engine and will need to buy an air compressor to run it.

I have no experience of compressors / air tools, but am considering a Hyundai

HY5508, 4cfm, 8ltr, 100psi, 550Kw £149.

Will this be adequate ?

I would appreciate any comments and advice

That one is 2 CFM FAD, which is the real air delivery.

This is from a random search Air compressor reviews

The 5724 might end up more useful.

If all you want to do is blow dust off or run your models, or inflate the odd tyre it will be fine, BUT if you want to do much else it will be to small. If it is low noise then it will be fine indoors, some compressors are very noisy. Good luck. Noel.

Thanks Dave did you mean 7524 ?

My little Draper air brush compressor, cost~£50, runs my Victoria just fine if that's all you want to do. a lot quieter and more portable than my bigger compressor.

I've had the Hyundai HY5508 for a few months. It runs my Stuart V10 effortlessly. I get about one minute of operation from the tank at a few psi before the compressor kicks back in. It's not silent but it is possible to hold a normal conversation next to it. I added a regulator to it. It comes with a Euro air fitting which I replaced.

It arrived from Amazon with a badly damaged air filter housing which I bent back in to approximmate shape. And it's Push/Pull On/Off switch is almost impossible to operate without lifting the machine off the ground.

But, otherwise it seems to be good enough. I plan to add an airbrush to it this year.

I think it unlikely it has the oomph for standard airpowered workshop tools - there's a chance it could drive small lightwieght ones, maybe.

Ches.

Edited By Ches Green UK on 31/01/2022 20:21:31

I have a similar model from Vevor, 750W, 30l tank. I suppose it comes from the same factory than the Hyunday ones, but as it is non branded it is much cheaper... (140£. I am extremely happy with it, as I am not using a pneumatic hammer or similar air hungry tools it does its job. Running a Stuart engine: no problem at all. I have a no9, with 1 1/2 x 1 1/2 it is comparable with a victoria from size point of view, no need for a bigger compressor at all.

I can run my compressor in the middle of the night without getting the whole street out of bed. Really silent. See it on the left hand side of  the lathe cabinet.

Edited By Gerhard Novak on 31/01/2022 21:38:41

Most first time compressor buyers go for a machine that is either too small or will soon be too small.

Free air delivery is important, but so is the motor rating (some will not like to run continuously for long!).

The size of the receiver may be a clue to how long the motor might run before getting hot.

Compressed air is not a cheap form of stored energy. You need to look carefully at all aspects before buying. My (second hand, at least) very old compound pump in cast iron has served me well. I most certainly would not want a direct driven ‘buzz-box machine (although I did buy a small compressor years ago) as my main machine). I took it to Scotland, but my step Son in law bought a larger machine, so I brought it home again. Not really used since.

A good 3HP unit will provide about 10CFM FAD. Modern cheap units are likely not up to that standard.

So much will depend on what you want to do with your engines. If just running slowly for display with no load then you will not need the volume or pressure that you would if say wanting the engine to run a dynamo or belted to some other model machinery.

For a number of years I used a noisy Machine Mart compressor with 5cfm displacement so probable 2.5-3 cfm FAD with a 12lts tank. It would cut in quite often but did provide enough air for display and the odd burst of speed but was rather off putting when the 95dB motor kicked in.

I now have the twin motor Hyundai which is so much quieter so you don't jump out your seat when the motors start up and being that it has a bigger tank and can refill it faster does not run as often or for as long. I went with the Hyundai as they were the only suppliers giving actual FAD as well as displacement figures as the reassurance of the name rather than buying from a forwarding agents warehouse who just fulfil orders from a little known name.

The Vevor model is 165l/min or 5.8cfm displacement - and even it is a no name, this data is available. FAD should typically be a third lower than that - so I suppose 3 to 3.5

I have the Hyundai compressor and find it very good for my needs.

It is very quiet which was a major plus for me, my older compressor would awaken the dead.

I only use it for blowing down benches and running my models, I have no need for air tools these days as I no longer want to spray cars or nail lots of timber.

As a small quiet compressor I can recommend it.

Ian

The ‘two thirds’ guesstimate rather depends on factors like compression ratio, piston leak-by, valve arrangement (and quality) and even operating temperature. Cheap ‘no-name’ compressors may exhibit the worst of all those factors.

It’s why I like my slow-revving compound pump with good cooling between the stages and possibly with a pressurised crankcase (to minimise any potential blow-by).