Noob question about air hoses

[mangocrazy]

I've recently availed myself of a special offer on a Metabo compressor (see other thread), now I want to start using it. First thing I want to do is to use it to pump up my bike and van tyres. I'm intending to get something like this:

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=380314019834&ssPageName=STRK:MEWAX:IT

However it needs an important bit to make it work; a length of hose between compressor and the inflator. Can you buy these off the shelf, or is it better to buy a length of the correct hose, some fittings, and make up your own? And if i make up my own, what is the correct hose, best type of fittings and will I need any special crimping tools or are jubilee clips up to the job?

Pardon my ignorance, I'm starting from a basis of no knowledge here and don't want to do anything which is stupid or dangerous.

 

[tigler]

First thing, the tyre inflator gauge in that link is rubbish ! The gauge will be inaccurate.
You're better off with a bog standard inflator, known as a tyre or air chuck, PCL are the best, and an separate accurate tyre gauge.
Air hose. They can be bought ready made with crimped in fittings, which it the best method for holding in fittings. Go for rubber, PVC is generally cr4p, although some of it is ok it's impossible to know from a picture. Another alternative is polyurethane if you can find it. With rubber, go for black, coloured hose generally deteriorates faster. Look for a working pressure of at least 10 bar. Bore size, 3/8 or 10mm minimum. Max length 15 mtrs, shorter is better.
Fittings can be almost anything, male or female threaded or quick release of many different types.
If the connection to the compressor is a cheap and nasty type, change it for a PCL or similar type coupling. You want a female quick release like PCL on the working end of the air hose. Then all air tools and attachments will have a compatible male part.

If your air hose has male threaded fittings you will need female thread on the chosen quick release fittings, or vice verse for females in the hose.

 

[rtbcomp]

It's dead simple to make your own - I use these people, their hose seems pretty good. I've had Machine Mart hose perish and crack in less than a year.

http://www.beal.org.uk/hoses-tubing-fittings/cat_30.html

They do a good line in "Jubilee" clips too, but you need to buy in bulk but they're cheap enough and always come in handy.

PS these guys also stock PCL connectors and inflator.

 

[madkayaker]

jubilee clips are frowned apron in industrial use as they can loosen and blow off the crimp clips are preferred and are fitted with either a special tool or a pair of end cutter pliers

 

[tigler]

They also have a tendency to catch on things.

 

[mangocrazy]

All I really need are a couple of airlines of differing lengths - say 3m & 12m (assuming end fitments are the same). Would there be any firms that could make up a set of crimped hoses to my specification? The compressor has two quick-coupler female outlets.

Also I notice in the handbook that it says this: 'Hazard generated by compressed air containing oil. Use compressed air containing oil only for air tools that require such supply. Do not fill tyres with compressed air containing oil'.

Does this mean I can't pump my b***dy tyres up with the thing?

 

[madkayaker]

there will be very little oil in the air unless there is an oil feeder on it the oil in the pump will stay in the crank

 

[mangocrazy]

So Metabo are just covering their @rses, then...?

 

[madkayaker]

probity a good thing to fit would be a filter/ dryer to the output especially if you plan to spray and your tools will last longer with no water in the air

 

[tigler]

Due to it being a piston type pump there will inevitably be some oil in the air as it is compressed into the receiver. With a compressor in good condition it won't really be a problem as the oil falls to the bottom of the receiver and becomes emulsified with the condensate water. To prevent any chance of oil in the air a filter would need to be attached before the outlet connections. Not particularly expensive or difficult to do.

Once you go beyond the basics there is quite a bit involved with compressed air !

 

[SC_BK]

Max length 15 mtrs, shorter is better.

Can I ask why? I have a 10mm rubbery air hose, think it's 10m long, and was thinking of buying another 10m or 15m to attach on the end, for blowing up tyres

 

[brightspark]

its not good practice using long lengths of hose. shorter the better .if using long lengths its better to use large bore pipe and keep in strait lengths otherwise u loose cfm and pressure

 

[mangocrazy]

To prevent any chance of oil in the air a filter would need to be attached before the outlet connections. Not particularly expensive or difficult to do.

The Metabo I've just bought has a Y-shaped outlet connector. Does that mean that some kind of filter arrangement should be fitted between the pressure regulator and the outlet, or would it be better to filter after the outlet?

 

[madkayaker]

between the tank and the outlet would be best

 

[tigler]

Can I ask why? I have a 10mm rubbery air hose, think it's 10m long, and was thinking of buying another 10m or 15m to attach on the end, for blowing up tyres

As mentioned above, the longer the hose the more pressure drop when consuming air. However, this is only really a problem with air tools where the pressure drop will reduce performance, there won't be a problem with tyre inflation.

The Metabo I've just bought has a Y-shaped outlet connector. Does that mean that some kind of filter arrangement should be fitted between the pressure regulator and the outlet, or would it be better to filter after the outlet?

For best practice it should be before the outlets but it may be ok after them.

 

[mangocrazy]

OK, cheers chaps. Next question is which one to get, I suppose. Max compressor flow rate is listed as 140 litres/minute in the specs, which (I believe) equates to 2.3 dm3/second. I Googled Norgren and whittled my choice down to these:

http://store.norgren.com/UK/en-GB/B...aximum_flow_decimetres_cubed_per_second%3d4.5

So I presume I can get by with a filter capable of passing 5 dm3/sec (i.e. the lowest spec they stock)? And do I just fit the filter between the pressure regulator and the outlet coupler? And will my fittings be 1/4" or 3/8"?

Sorry for all these questions; it's an entirely new subject for me, I'm afraid.

 

[tigler]

Norgren is top stuff. Port size will also be thread size in BSP. So 3/8 port is 3/8 BSP.
Look on ebay though, NOS or used stuff comes up regularly at big savings.