Thread: Equivalent to Qld's Trade Tools in Sydney? . .. and welding/compressor advice please

Update - conversion 15a to 10a

I thought I would mention this in case it is of interest to others - Even though I had bought a good quality and certified converter with built in trip switch from Jaycar I thought I should call BOC before using it.

Good news - they are quite happy I use it and say the worst that could happen is it will trip but certainly can't harm the compressor or welder, both of which have 15a plugs.

regards
Sean

Given that 15A->10A unit has a 10A breaker on it, you may find the breaker trips on higher amps (it depends on both amps and your welding duty cycle).

Somewhat perversely, a standard 10A GPO circuit would trip less, as it typically has a 16A or 20A breaker.

Yes good point I had wondered about that. I am yet to test it but will report on results when I do.

Hi Sean
Good luck with the new toys, both my Compressor and Welder are 40years old and still going strong, I have the cheap magnetic 90dec welding brackets and use compressed air to clean them if the air is handy.
I use a 10amp plug and replace it when it looks a bit ratty, make sure you use a good quality extension lead and as short as possible and make sure your shed has 2.5mm wiring. My welder is 160amp and lately doesn't pull 3.25mm rods well at all,it did when new so now i use between 2.0 and 2.8 rods for all welding, I just did a fillet weld 12mm to 25mm mild with 2.5 rods and I am very happy with the results.
That's my 2 bobs worth.

Try hare and forbes
Sydney tools or
Gas weld



Check me out:
www.facebook.com/steamjunkprops Or Steamjunkprops.deviantart.com

Good advice on keeping the extension leads short. If you get carried away with the compressor on a long lead it will bite you. By this I mean starting issues and reduced motor life, particularly if you run the compressor and the welder from a double power point. The start up current drawn by a single phase motor can be 10X the rated current, remembering that a compressor starts under load too, so extension leads are dodgy territory.
Good choices all round though.

I have now used both the 15a compressor and the 15a arc welder with the 15a to 10a converter mentioned above and both performed really well. The compressor manual (a real mishmash) emphasises again and again not to use extension cords but rather get more hose.

Another run-off question (very basic I am sure) in case someone sees this - my compressor seems to leak air via the connection to the air gun and and I can hear air coming out of the tank when the pressure cut-off has been reached and the motor has cut out - also when I switch it off the air pressure in the tank automatically runs down to zero. Is this a safety feature and normal? Thanks, Sean

Hi Sean, I have read through this thread and can drop in here with some answers and some perhaps unwanted information.

Re compressor. Not sure if your your first leaking issue relates to the blast that occurs when the motor stops, or you are saying that you can hear an ongoing hiss once the motor has stopped, so will cover both.

If you look at the compressor head unit, and follow the outlet pipe from the head to the tank, at the point where the pipe meets the tank there will be a substantial brass fitting screwed into the tank, with head pipe and a small copper pipe. The fitting is a check valve to ensure that pressurised air from the head can get to the tank, but air in the tank cannot flow back to the head once the motor cuts out. The small (typically 6mm) pipe goes to the pressure switch which controls the motor.

The pressure switch will be connected to a different point in the tank to sample tank pressure. When the pressure in the tank reaches the preset maximum threshold, the pressure switch will interupt the motor circuit stopping the motor. At the same time it will open an inbuilt air valve in the switch unit connected to the tube from the check valve.

When this valve opens, any accumulated pressure in the circuit from the compressor cylinder exhaust valves, through the outlet pipe to the check valve will be released in a sharp blast. I believe that this may be the first "leak" that you are hearing each time the motor cuts out. They use this system so that the manifold system is unloaded when the motor has to restart, if the system was fully pressurised the motor would stall and burn out.

The system should not leak down unless it is fitted with a bleeder valve. I have a 12YO 3HP 15cf/m compressor and it can hold pressure for months at a time while disconnected provided that I turn off the outlet cock at the regulator. If I leave the outlet cock open and disconnect the hose at the air fitting, it will leak down in about 24 hours, as the fitting does not provide a perfect seal. Some units may be fitted with bleeder valves to slowly bleed the tank, but I have not come accross one in a unit this size.

Provided that the leak is not worse than this it should not be a problem. This is because it is good practice to depreasurise the tank and open the water drain fitting at the bottom of the tank on a regular basis (daily for regular use, or at the end of a task if you are using the comp occasionally for short periods) to clear any water that has condensed in the tank after coming in as airborne moisture through the compressor. If the unit is bleeding down at a substantially faster rate, check the bleed down rate with the outlet closed, all hoses etc removed. Check that all high pressure unions are properly tight and not leaking, (water and detergent mix dribbled around fitting and look for bubbles). If there is no improvement, and the suppliers are not claiming a bleed down valve is installed, then it is likely to be a machine fault, most likely in the check valve or reed valves in the compressor head. If so refer back to supplier for investigatiion.

Re 10A to 15 A 'converter'. This unit can protect from electrical shock but cannot make an extra 5A capacity from nothing. It would more correctly be called an adaptor rather than a converter.

Within the house/shed wiring, it is permissible and normal to daisychain multiple 10A sockets on a single circuit, with the risk of incurring voltage drops at each cable junction in the chain.

When a device has a nominal load current approaching or exceeding 10A, and will by nature be subject to substantial peak currents for starting a motor or striking an arc, the manufacturers will be required to fit the appliance with a 15 A plug or specify that the unit be hard wired.

The significant difference here in either case is that the unit is provided with a dedicated (not shared) power circuit from the mains distribution panel to the 15A outlet or hard wired device. This minimises the voltage drop incurred by the unit, and reduces the likelyhood of other equipment being forced to operate below their minimum operating voltage. In all likelyhood, your 3 HP comp motor will be briefly drawing 50-80A each time it starts, and if connected at the far end of a daisychain of 10A outlets, the voltage drop incurred in the accumulated cable junctions can be enough to prevent the motor starting, or slow the starting process enough to damage the fixed wiring or motor over time. The plug adaptor with RCD (10A to 15A converter) cannot mitigate against this. Under no circumstances should you consider connecting two 15A plug devices into a circuit, be it dedicated or daisychained.

Hope this helps outline the power situation and explain what is happening with the compressor.

Thanks malb and for the detailed info - I will print this and check over the compressor with this in hand.

Points taken re 15A to 10A 'converter'.

regards, Sean

malb just to respond/comment on 2 points:

• I do hear the sharp blast when the motor cuts out - about the only thing in the manual which made sense - it was 'other' escaping air I was referring to;
• one hiss which seems unrelated to the compressor itself is that I can hear and feel air coming out of the area near the connection to the air gun.

thanks, Sean

Originally Posted by seanlark

one hiss which seems unrelated to the compressor itself is that I can hear and feel air coming out of the area near the connection to the air gun

Air compressor fittings always seem to leak, even though they really shouldn't. Domestic water hoses operate at similar pressures, yet they manage, mostly, not to leak.

That said, if you spend the time, you should be able to chase down the leaks and have it hold pressure. The common method is to use a spray bottle of water with a bit of detergent in it. You may also want to look at what air fittings are being used - they tend to vary in regard to air flow and propensity to leak.

Originally Posted by seanlark

one hiss which seems unrelated to the compressor itself is that I can hear and feel air coming out of the area near the connection to the air gun.
thanks, Sean

A few things to look for there.

Hose itself - Coily hoses have a smaller bore than heavy duty hoses and the fittings on them sometimes have a short 3 barb fitting pressed into the hose at each end, and a coil spring acting as a strain releif and retainer/crimp for the fitting. These hoses are prone kinking and if they get a couple of kinks in the same place, they will pinhole at the point and leak. This is also quite common at the ends as the end of the barb can pinch the hose and pinhole it. It can be resolved by sliding the spring relief/crimp back from the end, cutting the hose back square, slitting the loose end of the fitting, softening the hose end with hot water, pusing the fitting barb back into the hose and replacing the relief/crimp spring.

Hose end - has it been terminated with a male threaded end and then had a Nitto or other quick release socket screwed on, or does it have a a barbed QR socket crimped onto the hose. If it goes through threaded fittings, is there teflon tape or other sealant to prevent leaks at the junction. If it is a crimped on barbed socket the hose to fitting joint should be airtight. The female QR fitting (threaded or barbed) will have an O ring inside that should seal on the taper of male fitting it mates with, but poor machining of the male or female fittings can allow a leak inside the fitting. While there are plenty of fittings around, I have found that the quality control can leave a lot to be desired, so I only buy genuine branded fittings and avoid the knock off varieties.

Male fitting at tool - Tools normally come with a 1/4NPT threaded inlet and you install a male QR fitting to match the fitting system you are using. Is the threaded portion of the fitting sealed with teflon or some other sealant? Some tools will have a 1/4 male to 1/4 male threaded fitting installed with a fibre washer as a gasket between the tool and fitting. The washers can be a source of leaks, so I always remove these fittings and replace with QR fittings. Liquid sealant here is very unusual because of the possibility of uncured sealant getting into the tool and stuffing it.

Tool itself - Poorly made tools, tools that have sat unused for a long time, or tools that have a lot of use can leak at the gland seals for the trigger plunger. Depending on design and abilities, you might be able to dismantle the trigger assembly and replace the O rings in the seal, or if a new product, return it to supplier as defective unit.

I have had one cheapy tyre inflater with a porous casting. Unfortunately the air channel cast into the unit met up with one of the casting voids open to the surface. The manufacturer had put a plug of bog into the void to seal it, cleaned up the casting, and finished the unit with a single coat of hammertone. The unit was dropped once when out of warranty, allowing the bog plug to work loose the next time the unit was used, instant leak, kept for spares now.

Simplest way to check is to do the water and detergent test and look for bubbles to locate the source of the leak, then decide on the best approach to resolve it. Feel free to come back with details of hoses, fittings, tools etc if you cannot track the problem and I will try to be more specific.

Thanks malb that is mighty helpful and in fact you have hit on a couple of points I suspected might be issues but am surprised are.

As you say remarkable that hosepipes can go a fair way towards not leaking but air accessories (which rely on air pressure) leak.

to clarify:

• I did not use Teflon tape or similar
• the tool connector seems to be the male threaded variety you describe
• I did buy a set of Nitto-type connectors and used them
• a farming mate called around yesterday and checked it over for me - he said he has the same hassle with leaking connections and lives with it. He blames the poor quality connectors. My problem is I don't like to live with such limitations - I am new to this and have gone to a lot of trouble to buy a very good unit and don't want pressure lost due to leaks.

on the strength of your counsel I will go back over it and endeavour to identify exactly where they are leaking. In one case tightening a nut helped.

thanks
Sean

[QUOTE=malb;1675584.
Under no circumstances should you consider connecting two 15A plug devices into a circuit, be it dedicated or daisychained.

Hope this helps outline the power situation and explain what is happening with the compressor.[/QUOTE]

malb thanks for this advice on not using (in any shape or form) more than one 15A accessory on the 15/10A 'convertor'. My instincts had told me not to but very good to get it confirmed.

regards
Sean

thanks also RustyArc for comments which align with what malb suggested. I will use the soapy water test today and track down the leaking connectors as step one! Sean