which compressor

I am looking to purchase a low noise small compressor to run my 6 live steam model engines [ up to a twin stuart turner Victoria ] but I know nothing about compressors. SO hoping one of you can help me to decide what I need. a second hand one would be fine.thank you Alan

I have no idea about the volumes of air you might need but just wanted to say that owning an air compressor and you suddenly find all sorts of handy uses apart from topping up the car tyres - everything from blowing the cr@p off the lawnmower to cleaning out those blind screw threads and running a mister on the mill.

Mine was a cheapo from lidl that does the job but I wish it was bigger. Noisy- yes - but it's possible to fill the tank then lug it elswhere to use... or run a long line. A silent bambi is expensive.

As an out of the box thought... back when i was a kid and my dad used to take us camping he made up an adapter and filled the spare tyre to high pressure at the first garage we passed am and used that to inflate the air-beds come evening and the inner tubes we used when swimming.

pgk

How about roll your own from a defunct fridge or freezer?

The compressor units therein are fairly quiet, coupled up to a suitable tank to give some volume..

I was given a compressor because my brother couldn't stand the NOISE. Neither could I.

I now have 2 Bambi's, permanently on and no louder than the fridge, (probably because they use fridge compressors)

We had a storeroom in our workshop that used to be the sound proof room for noise testing Prestcold fridge units. It had a very strange dead atmosphere when the doors were closed, you couldn’t hear apprentices who were locked in either.

Mike

Edited By Mike Poole on 17/10/2018 13:29:56

Mike, was it silent enough to listen to your heart beating and the blood rushing around your body - Now that was Eerie!!
Ex Vickers Weybridge.

Fridge compressors ar good quiet option but fairly low flow. A few things to watch out for though. They are normally lubricated by oil in the closed system so you need libricator on the inlet. Not a problem with running engines or misters but you also need a cleaner on the tank outlet for other uses.
They are capable of very high pressures if left to run on their own. A pressure relief device on the output is a must.
It is illegal to relese the gas from a fridge so either buy a new compressor or get a qualified company to de-gas the fridge for you.

Robert G8RPI.

Don't understand your post Niel, but then again its hard to understand much on this forum

Anechoic? Silence? Neil does have a wide ranging sense of humour, so it does make some think a bit harder at times.

Edited By not done it yet on 17/10/2018 17:29:55

It's a sound-proof room 'anechoic chamber' as described above, but a well-known individual in rather famous shot...

I use a compressor regularly, quite late in the evening. I bought a "silent" 24 litre Orazi compressor from Amazon for £130.00: they do a smaller one for under £100.00. They are also on E-bay.

It is not silent, quite, but you can hold a normal conversation with ease when it runs. I only have a 14' x 8' garage, but if I am not next to it, I do not always realise that it has fired up if I am making any other noise.

**LINK**

Regards,

James.

Thank you James, A helpful answer at last, I will look into the Orazi in the morning alan

Direct drive reciprocating compressors are noisy, even small, 1 - 2 cu ft ones.

Belt driven compressors are quieter, because they run more slowly, but tend to be larger displacement, so are almost as noisy.

Diaphragm compressors are the quietest (Having to open up a Bambi, for a repair, found to my surprise that it is a reciprocating unit, although the packaage looks like a fridge compressor with a clamp around it instead of a welded join.

Machine Mart do a range of diaphragm compressors ranging from a single unit upto a triple unit.

Howard

My fridge freezer recently packed in and I looked longingly at the compressor, but a quick check on google soon made me desist. As was pointed out above it is too naughty to release the ozone munching gas. I had to part with 25 quid to get it disposed of properly, but I can sleep with a clear conscience. My new fridge freezer seems to use an ozone friendly gas, so if I am still alive when it packs in I might get my hands on the compressor.

Doug

How do automotive air-con compressors compare with fridge units? Anyone know? Obviously need a drive, for starters.

Price wise a lot more expensive.

A fridge compressor with starter electrics can be simply plugged into the mains to run.

An auto compressor needs a drive motor, motor pulley, drive belt, 12 volt dc supply to operate the drive clutch and special connectors for the pipeline. Overall, more effort, more noise, more space and more money.

My take on it:

There are plenty of scrap cars out there.

They will require rather more motor power than a fridge unit, so may possibly be able to run at lower speed and lower power - but have a far better output than any domestic freezer unit (about 160W?)

I would expect the clutch, required for a vehicle air-con system, could be short circuited or removed, so a 12 volt supply may not be required.

Pipes and connectors should not be an insuperable issue for an engineer. - the connectors are already there, in the car, anyway, so it just depends on where the lines are cut?

I was hoping someone would particularly have knowledge of the power and speed options. Possibly just too powerful?

Air con units must use a fair bit of power as I believe they disengage with kick down on automatics. I think 5hp has been mentioned.

Mike

That would be at fairly high engine speed, but they still work at engine idle speeds, too? I have a spare air-con unit available and that made me wonder whether one might be appropriate as a practical quietish unit. Mine is currently a good working spare and I don’t really need another compressor, so I’m not going to try it at this point in time.