Thread: Fittings and Hose reccomendations for Air Compressor

I'd be going for the larger hose and fittings. Less frictional loses in the hose. You can always used adapters at your tools as you say, or even have a short length of smaller hose for use on tools that dont require a large volume of air. This would mean that you don't have the weight of the larger hose hanging off the tool when you are using it.
You are probably aware of this but just in case you are not, you should also have a good adjustable regulator and a good filter/moisture trap.
regards
bollie7

Originally Posted by 19brendan81

I bought a Pilot K30 air compressor for a song last year and its time to hook it up. Its a big machine with a 150L receiver and nearly 700L per minute of free air delivery. As it stands now, it has a ball shuf off valve coming out of the receiver with a 1 inch BSP fitting in it. It also has a 1 inch BSP to 1/2 inch BSP reducer.

All the work that this compressor is likely to do in the short term is spray painting and running die grinders and polishers however eventually I will buy a rattle gun for it.

My question is, what size hose and coupler should I put on there? I plan on using the nitto fittings, and I think the size 20 one is what my current small selection of air tools uses...however this woould require reducing the 1 inch BSP fitting to 1/4 inch BSP in order to use the size 20 nitto range.

Alternatively, I could go up to a size 40 nitto range which would screw into my current setup as these use 1/2 inch BSP fittings....however I dont think many of the tools I own or are likely to own use this size without adapters.

Re hose, should I use 10mm or 12.5mm hose?

I think from my limited understanding of compressors that 12.5mm hose and size 40 nitto fittings are a better match for my big machine, but I dont want it to cause me grief with the spray guns that I am going to use (which is the main reason I bought a compressor).

What are your thoughts?

All the tools that you currently have will happily run on a 10mm air line and the size 20 nitto coupler. As far as rattle guns go, 1/2" will run fine but 3/4" and up will not work to their full potential.
I gather that you are using this as a stand alone unit and are not plumbing air lines through your shed etc. If so I would simply reduce down as required to suit your coupler, (best of all put in a T piece with a number 20 and number 40 nitto to give you the best of both worlds).
If you are plumbing your shed then I would use a minimum of 1" class 12 poly pipe as your supply line. Using poly has the advantages of no rusting, fewer leak points due to less joins, easy addition of subsequent outlets and easy installation. To add an outlet simply cut the poly, insert a t piece fitting and dropper and away you go.
When installing air lines it is always advisable to slope them back to the compressor as moisture will drain back to the receiver and collect allowing subsequent draining. Best practice is also to tap the droppers in so they come out the top of the supply main and then loop up and down finally as this offers the ultimate in moisture control albeit at the expense of more involved installation. Also of benefit is to place your outlet above the bottom of your dropper lines with a plug or valve that can be opened to allow moisture to be drained from dropper lines.
If you were to use say 2" poly pipe around a shed the volume of this line will add to your air receiver volume substantially, this is of benefit when running large rattle guns and the like, for the tools that you mention it would be of no real benefit.
Given that you are spray painting, pay serious attention to your moisture control and don't forget a filter regulator for all tools and spraypainting.

Thanks guys,

I had forgotten about a filter and reg. I am looking at some now. I notice that most of them, actually all the ones I have seen so far, are 1/4inch BSP. Is this going to be a choke point in my system if I go with 1/2inch hose and number 40 nittos?

Re plumbing the shed - I wasnt -planning on doing this as its only a small shed and not doing so will keep cost and complexity down.

Brendan

10mm hose would be plenty big enough... The restriction will be from the nitto air fittings, which do not have the throughput of the Ryco type.... But then the ryco type are a lot more expensive due to their unpopularity..

Is Nitto the best sort of fitting to get? Do they seal well? Nothing sh!ts me more when I am using air tools than leaking joins. I dont know why but the hissing drives me up the wall.

This compressor game is pretty confusing.

Most air leaks will be associated with the BSP fittings rather than the hose connectors.
Some of the cheaper Brass, Gal or Black fittings leave a bit to be desired,and screw into each other or the fitting or tool to far,loseing the sealing effect.
Also use a good quality tape or sealing compound on your joins,some of the cheap stuff is like using coloured gladwrap or plastic.

My compressors for painting corrugated iron roofs with the head of the gun some 200feet from the compressor was always set up to use 1/4inch hose and fitting. No lack of pressure feeding directly from the bellow shaped tanks on this. The compressors output was 25cubic ft. per minute and maintained a necessary pressure at the gun at 120lbs psi for oil paints.
The material hose was 3/8" and pressure in the 10gallon pressure pot was regulated to 100lbs psi. Air hose from the pressure pot to the compressor was 1/4"
This was in the days before airless painting equipment became affordable, well to me anyway.

Thanks for that Ruben..maybe I am best to stick with the 1/4 inch stuff. It seems to be the most common and my spraying requirements wouldnt be anywhere near as demanding as what you were doing with similar equipment.

If I am ever using a big air tool that I suspect is being limited by the smaller hose I will put in a T piece as Karl suggested so that I can run some bigger hose.

Brendan

You are correct, a 1/4" regulator will be a restriction, (1/2" are available), however for the tasks you have mentioned it will be no bother, I even run my 3/4 rattle gun through one, actually I think mine has 3/8 ports with ryco fittings, (if you didn't know there are large and small bore fittings available). If it were me, I would source a larger regulator more in keeping with the compressor you have. As to air fittings, the true nitto, (not chinese knock off), is a far superior fitting to the ryco design, although the ryco is more common. Steel ryco fitting are far more durable than the brass ones which I have found soon develop leaks if used in an industrial application.

I don't think Canberra would get very humid but I run two water traps in my workshop here in hot and soggy Bellingen!
The first trap is a Very simple shop built one and it's really effective. It is placed right next to the compressor and the factory trap is about 7m down the line and so far (5 months) it has not seen a drop of water. The simple shop built one really works a treat!

The water trap is a simply a T junction. The riser is a 2 meter 1/2inch copper pipe fixed to the wall plumb with a bit of wood as a backer to insulate it from the wall. It needs to stay cool so don't have it in direct sun light. The top of your pipe goes to your tools and the very bottom is where you put a ball cock valve. About 1/3rd up from the tap, come out in a T to your compressor.
The compressed air cools as it expands and passes through the copper riser and the water falls down the riser and collects just above the tap. Open the tap and it dumps the water straight on to the shop floor.

Very simple and it traps heaps of water.
Standard copper pipe is NOT certified for this application and it's up to you if you go down this path.
Maybe some other guys here might have an opinion on the safety of using copper plumbing pipe for compressor lines as i am a rank amature in that department. I have been told that copper pipes can burst throwing copper around your workshop!. It's worked for me for years with no problem. It's all standard plumbing with some silver soldered joints and some kinko compression nuts.
Don't use soft lead for your joints.

Also, standard carpenters site compressor hoses slip over 1/2 inch copper nicely and can be secured with steel hose clamps. If your fussy you can flare the ends and silver solder barb joins in. I have not had any slip off or any leaks.

Originally Posted by 19brendan81

Is Nitto the best sort of fitting to get? Do they seal well? Nothing sh!ts me more when I am using air tools than leaking joins. I dont know why but the hissing drives me up the wall.

This compressor game is pretty confusing.

Nitto is fine, unless like me you have all your tools rolling around on the concrete whilst cutting up cars and such, a few of my nitto fittings had got some impressive dents and beveling/scraping on the edges and didnt seal well anymore.
I had the old style fittings originally, but thought i would upgrade when i grabbed a new hole with nittos.

Dont worry, we all get p*ssed off with the hissing... but the worst is when you go to a workshop, and they use the same fitting with multiple tools!! cheap bastards, finger tight, hissing, WHYYYYYY